Professional brewers reminisce about their homebrewing experiences. Understanding pH: Alkalinity and Acidity

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FEDERAL AGENCY FOR TECHNICAL REGULATION AND METROLOGY

NATIONAL

STANDARD

RUSSIAN

FEDERATION

BEER

pH determination method

Official edition

Standartinform

Foreword

Goals and principles of standardization in Russian Federation established by the Federal Law of December 27, 2002 No. 184-FZ "On Technical Regulation", and the rules for the application of national standards of the Russian Federation - GOST R 1.0-2004 "Standardization in the Russian Federation. Basic Provisions»

About the standard

1 DESIGNED government agency"All-Russian Research Institute of the Brewing, Non-Alcoholic and Wine Industry"

2 INTRODUCED by the Technical Committee for Standardization TC 91 "Beer, Non-Alcoholic and Wine Products"

3 APPROVED AND PUT INTO EFFECT by the Order of the Federal Agency for Technical Regulation and Metrology dated December 18, 2008 No. 451-st

4 INTRODUCED FOR THE FIRST TIME

5 REVISION. February 2011

Information about changes to this standard is published in the annually published information index "National Standards", and the text of changes and amendments - in the monthly published information indexes "National Standards". In case of revision (replacement) or cancellation of this standard, a corresponding notice will be published in the monthly published information index "National Standards". Relevant information, notification and texts are also posted in the public information system - on the official website of the Federal Agency for Technical Regulation and Metrology on the Internet

© Standartinform, 2009 © STANDARTINFORM, 2011

This standard cannot be fully or partially reproduced, replicated and distributed as an official publication without the permission of the Federal Agency for Technical Regulation and Metrology

3 Safety requirements

3.1 Electrical safety requirements when working with devices - according to GOST 12.2.007.0.

3.2 The laboratory premises must comply with the requirements fire safety in accordance with GOST 12.1.004 and have fire extinguishing equipment in accordance with GOST 12.4.009.

3.3 When performing analyzes, it is necessary to comply with safety requirements when working with chemical reagents in accordance with GOST 12.4.103.

4 Measuring instruments, auxiliary equipment, reagents and materials

pH meter with glass and silver chloride electrodes (or combined glass electrode) with a measuring range of 0 to 14 units. pH and the limit of permissible basic absolute measurement error is not more than 0.05 units. pH.

The stirrer is magnetic.

Apparatus for shaking (shaker - "rocking platform") for various types of laboratory glassware.

Mercury glass thermometer according to GOST 28498. measuring range from 0 to 100 °С. value of division

Standard titers for the preparation of buffer solutions of the 2nd category pH 4.01; pH 6.86 (7.01) according to GOST 8.135.

Flask conical with a capacity of 500 cm 3 according to GOST 25336.

Washer n / e with a capacity of 250 cm 3.

It is allowed to use measuring instruments and auxiliary equipment with similar metrological and technical characteristics, as well as reagents in quality no worse than those indicated.

5 Sampling

6 Preparing to take measurements

6.1 Measurement conditions

When performing measurements, the following conditions must be observed:

Ambient temperature ......... from 15 ° C to 25 ° C;

Relative humidity, no more. . 90%;

Atmospheric pressure .......... from 0.08 to 0.1 MPa.

6.2 Checking the pH meter

The pH meter is checked using the buffer solutions specified in section 4 in accordance with the instructions for the device.

6.3 Preparation of buffer solutions

Buffer solutions are prepared according to the instructions for using standard titers for pH-metry.

6.4 Sample preparation

6.4.1 To free the beer from carbon dioxide, 200 cm 3 of beer is poured into a 500 cm 3 conical flask. The flask with beer is closed with a stopper with one hole, into which a thin tube is inserted to release the gas, fixed in the apparatus and shaken for 20-30 minutes.

The beer is then filtered through a pleated filter to further remove carbon dioxide.

6.4.2 When using a pH meter not provided with a temperature compensation system, bring the temperature of the sample to (20 ± 2) °C.

6.5 Storage and preparation of electrodes

6.5.1 Store the glass or combination electrode in distilled water, the reference electrode in a saturated potassium chloride solution.

6.5.2 Before measurement, the electrodes are thoroughly washed with distilled water and the remaining water is removed with filter paper.

7 Taking measurements

7.1 Take about 50 cm 3 of beer prepared according to 6.4 into a clean dry glass, lower the magnetic anchor to the bottom, place the glass on a magnetic stirrer.

7.2 Immerse the ends of the electrodes fixed on the tripod into the beer by at least 15 mm. include a magnetic stirrer and measure the pH value according to the instructions for the device with constant stirring.

The reading is recorded to the second decimal place.

8 Processing results

8.1 The final test result is taken as the arithmetic mean of two parallel pH determinations, rounded to the first decimal place, obtained under repeatability conditions at P = 0.95; if the acceptance condition is met:

where X,. X 2 - the results of two parallel measurements of pH in the sample; r - repeatability limit equal to 0.1 units. pH.

8.2 Reproducibility limit R - the discrepancy between two measurements performed under reproducibility conditions at P = 0.95, should not exceed 0.2 units. pH.

Limits of the absolute error of measuring the pH of beer using a pH meter with an electrode system g 0.1 un. pH at P = 0.95.

Lowering the pH of the mash is a fairly common task. We have already understood that it is quite simple, as well as. But how to lower the pH, you will learn from this article.

Lower the pH of the mash.

To lower the pH of the mash, calcium sulfate or simply gypsum is used.

Salt Calcium sulfate (gypsum, calcium sulfate 2-aqueous CaSO4 2H2O)

The difference between brewing gypsum and building gypsum is the level of its purification. Do not use ordinary gypsum from a hardware store. Although you can lower the pH, the beer will be spoiled and most likely contaminated.

Special gypsum for brewing, refined. The use of gypsum during mashing increases the concentration of calcium ions, lowers the pH of the wort, and stabilizes amylase. Especially recommended when brewing English style Pale Ale and Indian Pale Ale (IPA).

Dosage: a level teaspoon (about 4-6 grams) per 20 liters of beer, added to the water during the mash, before adding the malt.

Calcium sulfate (CaSO4) (Gypsum)

One tsp weighs 4.8g

Apply at the rate of one gram per gallon and add:

• 62 ppm calcium
• 148 ppm sulfate

Sulfate (SO4).

sulfates play leading role in giving beer bitterness and add a dry and pungent smell of hops to the drink. In addition, it slightly affects the pH level of the wort. The ideal sulfate concentration is considered to be 10-50 mg/l for light beer and 30-70 mg/g for dark beers. A higher concentration will increase the viscosity of the drink. However, in some beers, the concentration of sulfates reaches 100 mg/l and even 500 mg/l.

Calcium (Ca).

Calcium ions determine the hardness of water. Calcium performs many different functions in the brewing process: it lowers the pH during mashing, promotes the precipitation of proteins during boiling, stabilizes the brewing process, and acts as a yeast. The calcium concentration should be between 50 mg/l and 150 mg/l.

If the pH level of the water, on the contrary, is low, then you can always increase it by reading the article "" you will know how and how this can be done.

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Craft Brewing Business asks professional brewers to remember their experiences each year around Thanksgiving. home brewing and give helpful tips newbies ().

Be aware of oxidation

Gary Glass, Director of the American Home Brewers Association

The most common off-taste I've come across in my 16 years of judging experience is oxidation. Unlike other off-flavours, which can be eliminated by thorough washing and disinfection, changing the rate of addition of yeast or fermentation temperature, oxidation in beer cannot be completely eliminated - over time, all beer becomes stale. Oxidation characteristics vary considerably depending on the interaction between other components of the beer. Most often, when speaking of the characteristics generated by oxidation, paper or raw cardboard is mentioned, but oxidation, in particular, is more strong beer, may appear with notes of sherry or dried fruit, such as prunes or dried apricots. Oxidation can also create nutty taste. Sometimes oxidation manifests itself as a loss of flavor - the beer will appear bland or stale.

Homebrewers don't have access to all the cool bottling equipment that the pros have. But homeowners can do something to reduce the effects of oxidation and slow down the aging process of beer. Here are some tips:

• Pour your beer fresh. When the fermentation and maturation of the beer is over, immediately pour it into bottles or kegs.
• Avoid splashing beer when pouring.
• Adding a sugar primer right before bottling or kegs will allow the remaining yeast to use the oxygen dissolved in the beer.
• If you are spending forced carbonation in kegs, fill the keg first carbon dioxide and, if your system allows, use CO 2 to transfer from the fermenter to the kegs. But don't use this technique with glass fermenters!
• Do not leave more than 2.5 cm of empty space when bottling.
• Most importantly, store bottled beer in a cool place. High temperature accelerates oxidation, so cold storage will keep it fresh longer than room temperature storage.

What do you have in the water?

AndyMitchell, brewerNew Belgium Brewing Co.

Once you have mastered fermentation temperature control and yeast health, study the effect of water on beer quality and it will help you understand the difference between good and great homemade beer. Water is often neglected, even though it is the foundation upon which beer is built. It significantly affects not only the final character of the beer, but also the course of the entire brewing process.

With extract brewing, you get minerals from the extracts themselves (i.e. from the water they were originally brewed with), and then the water you use adds more minerals. It will be difficult for you to understand what you are working with, so in extract brewing, adding mineral salts does not make much sense. With grain brewing, you will be using tap water or building a water profile from scratch, which means you will have more control over the situation.

First you need to understand what is in your water. The main thing to pay attention to is the calcium content, the ratio of magnesium and chlorides, as well as hardness. In addition, it is worth making sure that the content of other ions is below a certain threshold. Chlorides and sulfates should generally be below 250 ppm. In water chemistry, pH and calcium are especially important.

When you feel comfortable, you can start making changes and see how it affects the finished beer. Understanding how water works will help you take a big step in understanding how raw materials and technology affect beer.

Unite people

Jamie Floyd, co-founder and brewerNinkasiBrewingCo.

You can pre-brew beer that will suit the table. Guests will be able to sip this beer while the new one is being brewed. You can brew the same recipe with changes according to your guests, or choose a completely different recipe. While I love the simplicity of brewing, it's fun to use the ingredients too. holiday table. If you're roasting pumpkin, for example, why not bake more and add it to your beer? You can, for example, brew a beer resembling Gingerbread Cookie that goes well with most desserts. You can even add spices for mulled wine or a little fruit pie. Remember that this beer is brewed for memories, not for winning competitions.

You can even arrange a friendly trip to the homebrew store or to pick up yeast at the nearest brewery. Ninkasi always shares yeast with local homebrewers if they bring a jar. Call ahead, check if your local brewery does this, and find out how to proceed. Everyone likes to get out of the house together. It may not be feasible for everyone to brew beer on Thanksgiving, but those who can make it their tradition will notice that every year more guests come to brew beer rather than treats.

Take notes, smart guy!

AnthonyStone, brewerDeschutes Brewery

For me, the paradox of homebrewing is that I give away my best beer and I don’t even get to taste it, and I quietly drink the worst myself to see where I went wrong. The most useful tool for me to improve my brewing prowess has been detailed notes. When you drink beer, you want to remember what you did and understand if you were right or wrong. Everyone cooks differently - someone likes to cook different each time, and someone prefers to cook according to the same recipe, bringing it to perfection. In any case, if you want to improve your skills, notes will come in handy.

When I try my new home variety, I add tasting notes and thoughts about what can be changed next time to the brew notes. I'm one of those homebrewers who likes to do something different every time, so in a year when I brew this recipe again, the notes will be very useful. In addition, keeping a record of what changes you make to a recipe will help you understand how changes in raw materials or technology affect the final taste and aroma of the beer.

I also advise new brewers to join a local club or find some kind of online community. Whatever problem you are facing, someone else has been through it before and will help you find the cause and solution of the problem. Looking at equipment, tasting each other's beers and sharing opinions is fun and inspiring. After all, good beer brings people together, and we don't brew it to drink alone at home. We brew beer because we love it and enjoy sharing it with others.

Sour!

Steve Breasley, Director of OperationsSkaBrewingCo.

Are you tired of fruit beer that tastes like soda? Tired of waiting six months to find out how the sour culture worked? Think about acidification in the boiler. Yes, Gose and Berliner Weisse have been in fashion for a couple of years, but there are other styles besides these German traditional ones. This is an interesting and not so difficult experiment for the homebrewer.

Experiment with lactobacilli - it could be a culture from a homebrew store or even some regular yogurt. Simply mash and filter as usual, bring the wort to a boil to sterilize it, and then chill to 40-43 degrees Celsius. Introduce lactoculture and act. The wort will need to be monitored and possibly even heated. IN industrial environment we stop acidification based on titratable acidity, but you can also just taste the wort and see if it's acid enough.

Even a small amount of naturally formed lactic acid can enhance many beer styles. The low level of acidification also minimizes the time required for this process. Try to reduce contact with oxygen in the process - close the boiler and, if possible, expel oxygen with carbon dioxide. This will help prevent other bacteria from entering the wort, which can produce unwanted off-flavours. When the desired level of acidity is reached, bring the wort to a boil and treat it like any other - add healthy and fresh yeast and other additives that you want. Although I've never really liked fruit beers, fruit goes well with kettle sour. Mmm, cherries, lactic acid and turkey!

AND last tip Thanksgiving - don't try to fly with homemade beer. In 1992, I had all my homemade pumpkin ale confiscated at the Missoula airport (don't judge me, I told you, it was 1992!), and my family was so upset... Well, they said so.

The Science of Disinfection and Temperature Control

Russell Carpenter,Ph.D., head brewerRocketFrogBrewingCo.

Brewing is both a science and an art. The Creator within us wants to create a beer that we can enjoy ourselves and serve to friends and family. The scientist within us wants to fine-tune every little thing to improve brew efficiency, hop utilization and quality consistency. Sometimes we dig too deep into variables, so we don’t know for sure which one helped us or, on the contrary, ruined everything. To me, the two most important parts of the brewing process are cleanliness and temperature control. Don't spend crazy money on a new kettle, mash pot, or conical fermenter. This can be purchased later. First of all, homebrewers are taught to be clean, but people sometimes cut corners. Don't forget to wash! There are many types of cleaning and disinfection products on the market. Choose the right ones and follow the manufacturer's instructions.

Second, invest in a refrigerator and a temperature controller, there are enough of them for sale online. You can connect the controller to a refrigerator or choose one that has inputs for heating and cooling, which is what I recommend. Temperature control during fermentation will allow you to brew beer with consistent quality while minimizing exposure to large temperature fluctuations. It will also allow you to brew lagers and pilsners that need 9-11 degrees Celsius to ferment. Once you've mastered the art of disinfection and temperature control, you're well on your way to brewing fantastic beer. This is where you might consider buying the shiny, conical fermentation tank you've been drooling over.

Don't go deep into the IBU

David Curtis, General Warehouse Manager, organizer of the annual homebrew competitionBell'sBrewery

There are two general approach to brewing - technical and creative. A technician brewer will be more likely to spend time planning the brew day, refining the recipe, and taking into account all the details that can affect the finished beer. A creative brewer is more likely to brew beer on a whim, adding a drop of this and a handful of that, often using ingredients he has or grows in the yard. Personally, I belong to the first category. I like to play with the numbers in the brewing program, trying to get within the range defined by the style guides. There's something very nice about having all the readings (gravity, bitterness, color, alcohol) fall into the style I want to brew. However, as a homebrewer, I've learned that balance is needed. It is the balance that makes the beer drinkable and keeps the brewer sane.

Instead of measuring hops accurately to the gram, learn how to make other changes to the process. Personally, I buy hops by the ounce (28.4g) and try to get each addition of hops in one ounce servings. If I feel that the IBU is too high or too low, I will move this addition towards the beginning or end of the boil, but I will not change the amount of hops. This significantly reduces the number of hop packets piling up in the freezer, which then have to look for use. Portions of 28 g are not always convenient to use, but in most cases I use them. Sometimes a half ounce of high alpha hops does go back into the freezer, but I usually find a use for it in my next boil.

Remember that calculating the IBU is like shooting into the dark. The condition of the hops, the strength of the boil, and three hundred other variables affect the result. If you learn to lean towards creativity and not go into details, you will sleep better and find balance in your brewing.

Let me remind you of the basics

Stephen Hale, founder and brewerSchlaflybeer

We will assume that you use the most the best ingredients that can only be obtained. So remember the basics: keep the temperature, simmer long enough (one hour), but don't brew for two hours or more - except for a special beer. Quickly cool the wort and apply correct amount yeast with a good dose of air or oxygen, and then leave the matter to nature. In essence, you are just a keeper of the reserve: you let nature do its work in the right environment that you have created for it.

Don't be afraid of the wild unknown

Bret Kollmann Baker, Director of OperationsUrbanArtifact

Using wild yeast and bacteria may seem intimidating and expensive at first, but with a few tricks you'll be able to make sour beer at home with ease.

Wild yeasts and bacteria are living things, which means they can be killed. Heat is your friend. You don't have to have a second set of equipment, just use heat sterilization to make sure the equipment is sterile before switching from sour to clear beer. silicone tubing, rubber plugs, stainless steel- all this can be boiled. High temperature sterilization for fermentation tanks should be avoided as the plastic may melt and the glass may crack. So choose a separate plastic fermentation tank for sour beers and keep it clean - like all other fermenters. It must be remembered that wild yeast and bacteria are always and everywhere, so it's not a big problem. You don't use the same knife to cut raw meat and then - without washing it - raw vegetables. The same basic principles of hygiene apply to brewing. Do not be afraid of dogmas. Keep clean and have fun.

Four main rules

AndrewFoss, mainbrewerSaint Benjamin Brewing Co.

Homebrewing for me, like for many professional brewers, was the spark that ignited the flame. I brewed my first beer (ESB from extract) and got hooked. I have always looked to the staff at my local homebrew store for advice, and over time I have developed my technique, selected my favorite ingredients, and matched best practices for my equipment. Here are a few important things I've learned while improving my beer.

• If you don't have temperature control, brew according to the season. Fermenting beer is usually heated a couple of degrees warmer room temperature so if you don't have cool place for fermentation (15-17 degrees Celsius), think of something that doesn't require strict fermentation temperature control (hint: Belgian ales and saisons).
• Make yeast starters or buy two packs of yeast. A starter is better because you know the yeast is healthy.
• Do not add yeast to too warm wort. This will cause them to grow exponentially, often leading to off-flavours.
• Aerate the wort! 45-60 seconds of aeration before adding yeast brings great benefit yeast health and fermentation quality.

It's quite common for me to sample beer from local homebrewers. And almost every time I feel some kind of defect, it is due to fermentation. When I judge homebrew competitions (not that I do it often, but it happens), choose the best varieties in a specific category is always easy because most of the samples suffer from poor fermentation characteristics. A simple recipe, but cleanly and properly fermented, will beat an outstanding recipe with fermentation defects anyway.

Choose fruits

Chris Hodge, Sales Director for the Brewing MarketOregonfruitProducts

Today, brewers are experimenting a lot with fruit, and we are often asked what styles of beer go with what fruit. No wonder: there are no less types of fruits than styles of beer - citrus fruits, berries, exotic tropical fruits… There are plenty to choose from. The combinations are countless, but their number is not so daunting when you think about correlating the flavor profile of the beer and the level of juiciness or acidity of the fruit. Here are some examples of combinations that have proved very successful with our customers.

• Kettle sour / gose: These beer styles are ideal for adding fruit because there is already some acidity in the taste of the beer. Stone fruits such as peaches, apricots or plums work quite well here. Less juicy but sour fruits like cranberries, rhubarb and passion fruit also pair very well with sour styles.
• Barrel Aged Beers / Stouts & Porters: This powerful beer needs a strong flavor - so for these styles we always recommend raspberry, blueberry and dark sweet cherry. Black currant and boysenberry are lesser known, but they also produce intense fruit flavors.
• IPA / pale / blonde / kölsch / pilsner: These beer styles are quite flexible and we always recommend citrus and tropical fruits. Try the grapefruit blood orange, mango, pineapple, pink guava or graviola. Another interesting experiment- try mixing citrus and tropical fruits.

It is difficult to make a mistake when adding fruit, but the best results are obtained by adding them on the second or third day of primary fermentation. You can get a more pronounced flavor if you add a second shot after a cold crush and leave the beer for a week to ripen with fruit.

Weld and repeat

Ryan Blevins, head brewerMad TreeBrewingCo.

More often than not, I see people always brewing new beers, never repeating recipes. Repeating and refining recipes will increase your brewing prowess. If the beer didn't turn out the way you'd like, figure out why. Everything may turn out to be simple - the problem is in the technology or the choice of raw materials. Maybe you didn't hit the right mash temperature and the beer came out drier than you'd like. Weld it again and change the mash temperature. Experiment with grist composition or hop selection, add minor changes to understand how these changes affect the flavor profile. I myself tried to change many things at once. Sometimes it works, sometimes it doesn't, but in any case it doesn't help to understand how this or that change has affected the beer. Be sure to take lots of notes during the process. Without detailed notes, you will never know what change has affected the finished beer.

Water, water, water (did we talk about water yet?)

Chris Wright, founder and head brewerPikespeakBrewingCo.

All historical styles of beer are due to differences in local water. Years ago, Dublin's brewers didn't set out to brew a stout—they brewed a beer that matched the local water. Dublin water has a high pH, ​​and heavily toasted grains lower the pH of the mash. This is how the stout style was created. Pay attention to your water - let it match the style you want to brew. The first step is to check the composition of the water. Use salts to change the composition of water from local sources or distilled water. The pH of the mash (and the pH of the finished beer) is affected by more than just ions. Remember that yeast is a living organism that needs nutrients and certain water molecules (calcium and magnesium). Learn everything you can about the chemistry of water in brewing and experiment. Boil one recipe in succession and vary the amount of calcium, chlorides and sulfates added to the water

And raw materials!

Brad Cooper, owner and master brewerSteamBellbeerWorks

I sure that best advice what I can give amateur brewers is to get acquainted with raw materials and technologies. World-class chefs are those who can imagine ready meal before he starts cooking, and knows exactly what kind of meat, vegetables and spices, what processing technologies are needed to create this dish. Likewise, the best of the best brewers know what will happen if they choose one hop over another, they know the subtle differences between Carafa I and Carafa II malts, they know how tiny changes in fermentation temperature affect the result. Imagine what end product you want to achieve, how it should taste, how it should look and smell, then tap into your arsenal of raw materials and technologies to make it happen.

Create your philosophy

Craig Torres, founder and ownerHopcitybeer &wine andbarleygardenKitchen&Craft

We at Hop City are lucky to see so many of our homebrew clients moving into the big leagues, and we're very proud of them. All of our successful alumni have one thing in common: they have created a recognizable character. Here's what I mean: you don't have to brew all styles of beer - IPA, pale, amber, and so on. Instead, figure out what makes your beer stand out - be it style, hop profile, yeast selection, etc. As a home brewer, you can and should experiment. It's fun. But when you're serious about taking the next step, it's time to decide what will be your brand's anchor.

I don't want to say that your creativity for the rest of your life should be limited, for example, to saisons (unless, of course, you yourself want it). When we think of Stone, for example, we immediately think of their famous IPAs. They brew a lot of great beers in other styles, but their identity is built on what they do best. Ballast Point has a fish feature, but they are also known for their fruit additives. Either way, their success is undeniable. When you drink any grapefruit IPA, you unwittingly compare it to Sculpin.

When your friends drink your beer, ignore the insincere praise - listen to real reviews "after a couple of glasses." You will quickly notice which of your strains really stand out and where you can change something for best result. In this world where breweries are on every corner, you can still stand out. Before you go, find your star.

The active acidity of barley wort is higher than the acidity of barley-rice. Perhaps this is due to the different quantitative composition of protein substances and amino acids in the experiment and control.

In contrast to the wort, the pH of barley and barley-rice beer practically did not differ from each other and amounted to 4.71 and 4.60, respectively. Thus, despite the difference in the acidity values ​​of the wort, the pH of the beer decreased during the fermentation process, and in the finished drink, barley and barley-rice beer were almost equal in this indicator.

As you know, the decrease in pH during fermentation is due to:

§ formation of organic acids through deamination;

§ yeast consumption of primary phosphates;

§ the use of ammonium ions by yeast (-NH 4);

§ absorption of potassium ions by yeast and release of hydrogen ions into beer;

§ the formation of carbon dioxide.

The active acidity of the finished beer should be in the range of 4.2-4.5, therefore, the pH of both beer samples is higher than these values, which, as well as an insufficient decrease in the beer extract, indicates an unfinished fermentation process.

3.3. Titratable acidity of wort and beer

Titratable acidity was determined in the hopped wort and in the finished beer (p. 2.2.2.5, p. 2.2.2.6). The results of the analyzes are presented in table. 3.1.

IN barley beer titratable acidity was 3 cm 3, and barley-rice - 2.7 cm 3. According to GOST R 51174-98. "Beer. Are common specifications»for beer with an initial extract of 11%, the titratable acidity should be in the range of 1.5-2.6 cm3. Consequently, barley beer exceeded these values, and barley-rice almost matched.

Thus, during the research it was found that the acidity of the wort is lower than the acidity of both barley and barley-rice finished beer. This indicates that the fermentation process is not fully completed.

To determine the total nitrogen in the studied samples of wort and beer, the Kjeldahl titrimetric method was used (p. 2.2.2.7, p. 2.2.2.8). The results obtained are presented in table. 3.1.

The content of total nitrogen in barley wort was 1.41 g/dm 3 , while in barley-rice wort it was significantly lower - 1.05 g/dm 3 . As you know, the amount of proteins in the wort should be in the range of 1.0-1.5 g/dm 3 . Comparing the obtained values ​​with the generally accepted ones, it can be seen that the experimental and control wort met the necessary requirements for this indicator.

In the wort with the addition of rice in the grist, the amount of total nitrogen was less by about 1/3 compared to the control sample. This is due to the fact that when mashing the wort using rice, decoction was carried out (boiled at 100 Cº). Therefore, part of the proteins denatured and was removed from the wort during its further filtration.

In addition, the protein content in rice is less than in barley (Table 1.15). Therefore, in barley-rice wort, the amount of total nitrogen will be less than in barley.

Martin Brungard, a 25-year environmentalist, BJCP judge and developer of Bru'n Water beer preparation software, has written in depth about the effect of water composition on the taste of beer. This information will be useful for both homebrewers and professional brewers-technologists, as well as anyone interested in beer and brewing. The first - theoretical - tells about the sources of water, its mineral composition and the impact on the taste of beer.

Photo: Bites n'Brew

Introduction

This article provides basic knowledge useful for understanding the chemistry of water in brewing. Water is the main and most important building block in brewing. The volume of water in beer can reach up to 97%, so it is the most important component beer. Many ions and substances can be dissolved in water. Although water seems simple, its ionic composition can greatly influence the quality and perception of the finished beer.

1. Water sources

The origin of water has a direct impact on its suitability for brewing. Some brewers rely on city tap water, while others may have their own wells, wells, rainwater collectors, and other local sources. The type of source can also affect the amount of water and the consistency of its mineral composition.

City springs usually have confirmation that the water is safe and drinkable. Urban water treatment plants usually use open sources (rivers, lakes and reservoirs) and underground sources (wells and wells). Various processes can affect the quantity and quality of water from a source throughout the year. For example, large amounts of snowmelt or heavy rainfall can bring more soft water into a surface source, which at other times of the year becomes more mineralized due to groundwater. In addition, urban water sources may change between surface and underground during dry periods.

City water treatment plants are required to disinfect drinking water and maintain disinfectant properties in the plumbing system. Most often, halogen compounds (usually chlorine) are used for these purposes. If raw water is not suitable for drinking due to its hardness or excessive mineralization, water treatment plants can treat the water to reduce hardness or mineralization before sending it to the consumer through the water supply.

The various ionic constituents of water can affect the mashing process and taste sensations in finished beer. The ions enter the water primarily from the soil and rock minerals it comes into contact with as it flows through its environment. In areas where soil and rock minerals are less soluble, the level of water mineralization may be less. In turn, if the soil and minerals are more soluble, a significant amount of ions can dissolve in water. The influence of these dissolved ions on the brewing process is presented in the following parts of the article.

Wells are fed with water from underground aquifers. If these layers are isolated from lakes, rivers, swamps and sea ​​water, the water quality of them is more or less constant throughout the year. Wells that are not isolated from lakes and rivers may have water quality very similar to that of the system to which they are connected. As with surface sources, groundwater salinity is affected by the type of soil or minerals through which it flows. Groundwater flowing through limestone and gypsum formations is usually harder than water flowing through granite or limestone.

Wells are filled from other groundwater sources. As with the sources described above, understanding the quality of the well water is also important. The taste and ionic composition of the water must be suitable for brewing, and the water must be free of chemicals and microbes. Landfills, waste dumps and wastewater treatment plants are examples of industries that can affect the condition of an underground source. The origin of well water alone cannot be a guarantee that it is safe to drink and suitable for brewing.

Water in rivers and lakes can change its quality during warm periods due to the natural increase in the number of algae and microbes (blooms), which can give it an unpleasant taste and smell. These flavors and aromas can remain in water after it has been treated in municipal wastewater treatment plants and introduce unwanted flavors and aromas into beer.

If the water available to the brewer is of poor quality, additional water treatment can help remedy the situation. Activities such as distillation, reverse osmosis, carbon filtration, water softening with slaked lime (Clark reaction), boiling, addition of minerals can improve the quality of water from the source. Understanding the source of water, its limitations, and its propensity to change can help improve the quality and integrity of the product.

2. Minerals and brewing chemistry

Minerals dissolved in water have an important influence on the overall chemistry of the brewing process. Ions from these minerals change the pH of water, its rigidity , alkalinity , residual alkalinity And mineral composition . These parameters are the most important factors in determining the suitability of water for brewing. Changing one setting may affect others. A discussion of each of them is presented below.

2.1. water pH

pH is a measure of acidity or alkalinity aqueous solution and depends on the concentration of hydrogen ions (H+) in the solution. Very small percentage of water molecules (H2O) in solution naturally breaks down into two ions: a proton (hydrogen nucleus, H +) and hydroxyl (OH-). Neutral pH (7.0) indicates equal amount these ions in clean water(at 25 degrees Celsius). Acidic solutions have a pH of 0 to 7, while basic solutions have a pH of 7 to 14. The pH of typical municipal tap water is between about 6.5 and 8.5. The graph below shows the pH range of a conventional tap water and pH of the mash during mashing.

pH raw water, used in the process of brewing beer, has no particular important for the brewer. The main interest is in the pH of the mash during mashing. Factors such as water basicity and malt grist have a greater influence than the initial pH of the raw water.

The pH of the mash affects various factors, including: fermentability, color, clarity, wort and beer flavor. A slightly acidic mash between 5.2 and 5.8 pH (at room temperature) improves enzymatic processes during mashing. The lower values ​​of this gap give a more fermentable wort and a thin body. These settings also increase mashing efficiency, achieve a lighter color, improve protein coagulation in the boil, and result in a less cloudy beer. By allowing the pH of the mash to drop below these values, the potential for dissolving excess proteins in the wort can be increased (De Clerck, 1957). Higher values ​​in this range produce a less fermentable wort and a denser body (Briggs et. al., 1981). Adjusting the pH of the mash allows the brewer to produce a wort with the right character needed for the finished beer. In most cases, keeping the mash pH between 5.3 and 5.5 is recommended.

Even small increases in mash pH can lead to problems in the finished beer. The elevated pH of the wort and beer makes the bitterness in the beer coarser and less pleasant. The isomerization of alpha acids during the boil increases as the pH of the wort increases, which can add excessive coarseness. Another problem is that the high pH of the wort and finished beer slows down the reduction of diacetyl levels in the beer during maturation. Mashing at a pH greater than 6.0 can leach unpalatable silicates, tannins, and polyphenols from the grain into the must (Briggs et. al., 1981). pH drop wash water up to 5.5-6.0 can help avoid mash pH rise during flushing.

The pH reading depends on the mash temperature. There are two main factors that affect measurements. The first is chemical changes caused by energy changes in the water, which makes it easier for hydrogen protons (H+) to break away from the acid molecules in the mash. The second is the change in pH meter electrode response with temperature. These two factors give a pH reading 0.2–0.3 higher at 60 degrees than when measured at room temperature. Therefore, it is worth standardizing the pH measurement temperature. All pH values ​​presented in this article are measured at room temperature (20-25 degrees).

Brewers should note to themselves that ATC (ATC - Automatic Temperature Compensating, Automatic temperature compensation - ed.) only compensate for the response of the pH meter electrode to temperature changes. This function does nothing to compensate for the real increase in pH that was mentioned above. All pH measurements should be made at room temperature. Also, it should be noted that in most pH meters the electrode is a thin glass bulb, which will be subjected to more stress when measuring at high temperature which will lead to its premature failure. Based on this, the use of ATC pH meters is not in demand in brewing, since it is still necessary to lower the measured sample to room temperature to avoid variability in readings and damage to the pH meter electrode.

Note 1: pH meters require regular calibration to check their measurement accuracy. It is recommended to use calibration buffers 4.86 and 8.01. Store your pH meter as directed in the instructions for use.

Note 2: Plastic pH strips, often used by brewers, are reported to give inaccurate readings, 0.2–0.3 units lower than real ones. Use caution when using pH strips to measure mash pH. If it is not possible to measure pH by other means than pH strips, the brewer is advised to obtain pH values ​​0.2 units lower than planned so as not to exceed the allowable pH. pH strip readings in the region of 5.0–5.2 indicate an acceptable pH level of 5.3–5.5. Since the principle of pH strips is their reaction with ions dissolved in water, the relatively weak ionic activity of a particular water may not give a quick reading. Manufacturers recommend leaving the strips in the solution for at least a minute. Paper pH strips are not recommended for use in brewing as they are less accurate than plastic ones.

2.2. Rigidity

The hardness of water is primarily related to calcium and magnesium in its composition. A high concentration of calcium or magnesium ions produces hard water, while a low concentration produces soft water.

A common misconception among brewers is that hard water is undesirable for brewing. It is not true. A more appropriate description of the suitability of water can be expressed as follows:

Rigidity → Good

Alkalinity → Bad

The hardness or softness of the water does not indicate suitability or unsuitability for brewing. As will be shown in the following sections, both very soft and very hard water can be used if the appropriate alkalinity is achieved for the mash. Although brewing often requires a minimum amount of calcium, medium to high hardness water may be desirable for certain styles of beer. Although contrary to the above, a certain level of alkalinity may also be required. The problem is that so many water sources have too much alkalinity than is required in brewing. High alkalinity can lead to too high a mash pH.

Water hardness can be permanent or temporary. These forms of rigidity will be discussed next.

• Temporary (removable) stiffness - the result of the combination of calcium or magnesium with carbonates and bicarbonates in water. Temporary hardness can be reduced by boiling or softening with calcium bicarbonate.
• Permanent hardness - the result of the combination of calcium or magnesium with anions such as chlorides and sulfates. These compounds cannot be removed by boiling. Measures must be taken to reduce the permanent hardness of the water. Among them - distillation, deionization, reverse osmosis.
• General hardness is the sum of temporary and permanent stiffness.

2.3. Alkalinity

Alkalinity- a measure of the "buffer" capacity of a solution and its ability to neutralize strong acids and resist pH changes. Alkalinity is expressed as the amount of acid required to lower the pH of a solution to a certain pH (usually 4.3–4.5). Alkalinity is mainly related to the concentration of carbonates (CO3), bicarbonates (HCO3) and hydroxyls (OH-) in water. Higher alkalinity requires more acids to change the pH.

Alkalinity has a significant impact on the taste of beer. The increased alkalinity can cause the wort and beer pH to be too high, which will affect the taste of the beer. High wort and beer pH can produce "dull" flavors, coarse bitterness, and dark beer color. Accordingly, when the alkalinity is low, the pH of the beer and wort will also be too low, which in its own way affects the taste of the beer. The taste of beer differs from the taste of wine mainly due to the difference in alkalinity between beer must and wine pulp. The taste of wine can be described as sweet and sour, while that of beer is bittersweet. The acidity of wine maintains a balance with its sweetness, while in beer this role is played by hop bitterness. The alkalinity of wine pulp is usually negative, because. its pH is below 4.3. After fermentation, the pH of the wine usually drops to values ​​of 3.0-3.5. The alkalinity of beer wort keeps the pH of the beer in the 4.0–4.5 range and helps to avoid a tartaric character.

Even when using very low alkalinity water, the malt components buffer the wort and produce a pH in the acceptable range (5.2–5.4). Brewers should avoid over-oxidizing the wort if they do not want a beer with a tart or winey character. The influence of water alkalinity on the brewing process can be estimated using the concept residual alkalinity.

Residual alkalinity (RH) is a value derived from the hardness and alkalinity of the water to help estimate the potential pH state of the mash. OS was described in the 1940s by Paul Kohlbach. He showed that during mashing, the calcium and magnesium in the water reacted with the phosphate constituents (phytin) of the malt, producing acids that neutralized the alkalinity of the water. This interaction of water hardness and its alkalinity is expressed residual alkalinity . OSH is a specific indicator in brewing and an important factor in determining the suitability of water for brewing. OG is calculated using the formula where calcium, magnesium and alkalinity are indicated in mEq / l or ppm (Parts Per Million). The equation below assumes ppm as CaCO3.

With OS, the brewer can better understand the interaction between alkalinity and water hardness and its impact on mash chemistry and performance. A simplified diagram showing alkalinity, hardness, and RH is shown below. Lines of constant OR cross the graph diagonally. This graph is based on the work of A.J. Delange.

As you can see from the graph, the RH can be changed by adjusting both hardness and alkalinity. Alternatively, "burtonization" of water by adding gypsum and/or magnesium sulfate is an example of reducing OR by reducing alkalinity. Boiling degassing of water can be used to reduce the RH with high avoidable hardness values, as this process reduces the alkalinity. Dilution of water with distilled water or reverse osmosis water reduces the ROI of the diluted water.

The OR gives a rough idea of ​​what the final pH of the mash will be and if there is a need to adjust the water characteristics. While the graph suggests that beer color affects desired OT, the relationship is more complex. The acidity provided different types malt is out of proportion to the color they give the beer. Therefore, there can be no direct connection between beer color and OG.

The various malts used in brewing can be broadly classified into four categories: base malt, caramel malt, roasted malt, and sour malt. Each category has various characteristics acid content.

• Base malts are malts that have not been heat-treated to convert their starchy content into sugars, and that have a relatively low color (<20 Lovibond или <52 EBC).
• Caramel refers to malts that have been heat-treated to convert their starch content into sugars and have a color up to 200 Lovibond (~530 EBC).
• Roasted malts- malts that have been roasted to a color greater than 200 Lovibond (~530 EBC).
• Sour malt- Pale malt that has been sprayed with lactic acid and used to adjust the pH of the mash.

The acid content of roasted and acid malts is relatively constant in each category and their acid content does not change significantly with color change. In base and caramel malts, the acid content does change with their color. The table below describes the main changes in acid content for different malt categories. Information on malt acid content was taken from a study done by Kai Troester, 2009. Be aware that there are grains and malts that do not quite match the ratios shown below. You should not rely on color when predicting the pH of the mash.

Even though there may not be a direct and exact relationship between beer color and OG, the general relationship is clear. Lighter colored drinks benefit from low OT and dark varieties from high OT. As the acid content of the mash increases, the OR of the water must also increase proportionately to maintain the correct pH.

Success in the production of light beer in Pilsen in the soft and low alkaline water found there (OS around 0). While Burton-on-Trent's pale ales are famous for their very hard water, although its OR is just as low. Low OR waters are well suited for lager beer production, as The pH of the mash is more likely to be in the right range. This water is not as well suited for brewing dark beers, because acidic dark malts in the grist can push the pH of the mash below the desired values, reducing enzyme efficiency and possibly imparting a sharp, sour, and astringent character to the beer.

Success in producing dark beers in places like Dublin, Edinburgh and London where the water has a high OSH has been attributed to the use of dark grist malts. The increased alkalinity of the water, and the resulting higher OR, moderates the increased acid content of the dark grains, allowing for the softer-tasting dark beers brewed in these areas. These conditions have given them a reputation for making good dark beers. Without the additional addition of acidic dark malts to neutralize the high alkalinity, the mash pH would not drop into the desired range for good enzyme activity and the resulting beer could have a harsh character due to the leaching of silicates, tannins and polyphenols into the wort during mashing. Good quality pale beer is much more difficult to produce in these areas unless the alkalinity of the water used is reduced. When using water with increased alkalinity for the production of light beer, additional addition of acids is required. For this purpose, you can use an acid rest during mashing, sour malt or liquid acids.

Controlling the acid content of the malt bill and the alkalinity of the water is essential to produce a mash that has a pH in the optimal range of 5.2 to 5.8. Enzymatic processes in the mash are hindered when the pH of the mash is outside this range. Enzyme activity depends on pH and temperature, as shown in the graph (Palmer, 1999).

As can be seen from the graph, various enzymes work well over a wide pH range. Therefore, hitting the right pH values ​​is not critical to success. Achieving pH values ​​that are within one tenth or two of what is desired may give acceptable results. General recommendations for mash pH guide values ​​are given in the table below.

2.5. Mineral composition

Dissolved minerals (ions) are generally present in all natural waters, although their concentration in rainwater can be very low. The type and concentration of these dissolved minerals can have a profound effect on the suitability of water for use in brewing, mashing performance and beer taste perception. A discussion of dissolved minerals that are of particular relevance to brewing is provided below. Minerals form ions when they dissolve in water. Ions can be positively charged (cations) or negatively (anions).

2.5.1. unwanted ions

First of all, the water must be of high quality and drinkable. This implies the absence of contaminants, iron, manganese, nitrites, nitrates and sulfides. Organic and chemical contaminants have no place in beer. The ions discussed below are often found in tap water, but their concentrations must be low so as not to affect the beer.

Iron may be tasted in water at concentrations greater than 0.3 ppm (mg/L). Iron has a strong metallic flavor and is very easy to bring into beer. Popular guidelines state that the concentration of iron should be below 0.1 ppm to avoid its taste in beer.

Manganese can be felt at concentrations above 0.05 ppm. Manganese has a strong metallic taste that is clearly felt in beer.

Nitrates not a big problem in brewing, but as a general rule, they should be kept below 44 ppm - high concentrations can cause poisoning in children. 44 ppm nitrate is equivalent to 10 ppm nitrogen. The threshold of their perception in water is about 44 ppm. The optimal value for brewing is no more than 25 ppm (De Clerck, 1957). High levels of nitrates in water can cause them to be converted to nitrites during mashing, and levels above 0.1 ppm in the medium make it poisonous to yeast.

Sulfides in water can give smells of sulfur or rotten eggs, which also have no place in the finished product.

2.5.2. Major ions in brewing

The main ions that are of interest to the brewer are listed in the table below. These ions have a huge impact on the quality and perception of beer.

This table can also be compiled in a different way. Calcium, magnesium, and bicarbonates provide hardness and alkalinity, which affect the pH of the mash. Sodium, chlorides, sulfates, and magnesium all contribute to the taste, adding important nuances to the overall beer experience.

A discussion of the influence of each of the ions is presented below.

Calcium - the main ion that affects the hardness of water. It has a beneficial effect on enzymatic processes during mashing and is important for yeast cell walls. Regular wheat or barley wort has enough calcium for yeast health. In the mash, calcium reacts with malt phosphates (phytins), lowering the pH of the mash and precipitating calcium phosphate into solution and releasing protons. Calcium improves bruch and yeast settling, and limits silicate leaching from malt husks. It also reduces haze and "gushing" in the beer, speeds up the mash filtration and rinsing process, and improves hop flavor in a positive way. The ideal range for calcium in water for ales is 50–100 ppm. Exceeding these values ​​can cause excessive precipitation of phosphates from solution, which are important nutrients for yeast. Because in the course of the same reactions, oxalates (salts of oxalic acid) are also released from the solution, an insufficient amount of free calcium ions leads to the formation of beer stone on the equipment (calcium oxalate). To avoid its formation, the recommended concentration of calcium in water is at least 40 ppm. Lower concentrations may be acceptable for the production of beers such as pilsner, with the understanding that additional measures may be required to ensure proper beer clarification and removal of beer stone. Using water with a low calcium content will not affect fermentation in any way. barley and wheat have enough for yeast. The main problems with the use of such water are the deterioration of the sedimentation of the yeast and the formation of beer stone. These issues can be addressed by methods such as beer lagering, beer filtration, and chemical treatment of stone removal equipment. The calcium content should roughly match the level at which the particular yeast has evolved. For example, English yeasts thrive in high calcium environments, while Czech yeasts grow very low. Another consideration is that the calcium content of the water can be varied to increase or decrease the sedimentation ability of the yeast. For example, if the yeast falls out prematurely, you can reduce the calcium content to prevent this situation. Lager production always uses low calcium water for best results. Increasing the calcium content can be a useful tool for lowering the pH of the mash water. Calcium has little effect on the taste of beer, but pairs with anions that can increase the mineral flavor at high concentrations. Another problem that can be encountered with high calcium concentrations is that calcium replaces magnesium in yeast metabolism, which negatively affects their condition and performance. Avoid excessive calcium when yeast performance is below expectations. (Note: Adding calcium to the wash water will not affect the pH as there are no malt phytes. Acids should be used to lower the pH of the wash water)

Magnesium- the second ion that determines the hardness of water. It emphasizes sour and bitter flavors when present at low concentrations, but makes them astringent at high concentrations. Magnesium is a nutrient for yeast and an important co-factor for some enzymes. Like calcium, magnesium reacts with malt, but with a weaker effect than the former. The preferred concentration of magnesium is from 0 to 30 ppm. It is not recommended to exceed 40 ppm. A minimum value of 5 ppm has a positive effect on yeast sedimentation - barley or wheat in the mash will easily provide this concentration. Increasing the concentration of magnesium in water in order to lower the pH is ineffective, because. the allowable concentration of this ion in brewing is small.

Sodium The sour, salty taste of sodium enhances the taste of beer when present in small amounts. It is poisonous to yeast and gives a rough taste at high concentrations. It enhances the taste when present with chlorine and gives it a "roundness". The preferred sodium concentration is 0 to 150 ppm, but the upper limit should be reduced in water with high sulfate concentrations to avoid harshness and harshness in taste. The recommended maximum concentration in practice is 100 ppm, but brewers should remember that water in historical brewing centers has no more than 60 ppm. It is highly recommended to stick to no more than 60 ppm sodium concentration. While these recommendations are almost universal for any beer, some historic styles like Gose may have higher sodium (~250ppm) as part of the desired flavor profile, but this sodium is usually added to the fermented beer.

ions chlorine emphasize fullness and sweetness, and improve the stability and clarity of the beer. The ideal range is 10-100 ppm, but the upper limit should be lowered in water with high sulfate concentrations to avoid harshness or mineral taste. When using water with a sulfate concentration of more than 100 ppm, it is recommended not to exceed the amount of chlorine by more than 50 ppm. The mineral flavor of Dortmunder Export is associated with chloride concentrations of 130ppm and sulfates of 300+ ppm respectively. Please note that chlorine ions are not the same as chlorine-based disinfectants.

sulfates provide a sharper, drier feel in heavily hopped beers. Ideal concentrations range from 0 to 350 ppm, although you should not exceed 150 ppm unless the beer is heavily hopped. Concentrations above 350 ppm introduce sulphurous aromas into the beer. For this reason, blindly copying Burton-on-Trent's water profiles is not the best way to get the perfect beer. Sulfate content should be relatively low when brewing a continental lager using classic noble hops, as the drying properties of sulfate in hop bitterness are unacceptable with these hop varieties, and interfere with the maltiness characteristic of such beers. However, even when brewing beers with a malt emphasis, adding some sulfates can help make the finish dry without being too full and annoyingly enveloping.

Bicarbonates are a strong alkaline buffer, and are usually responsible for the alkalinity of most types of drinking water. The acids produced during mashing can neutralize some of the bicarbonate in the water. If there is not enough acid in the malt to neutralize the bicarbonates in the water, the pH of the mash may not drop to the optimum, which will weaken the fermentation processes and make the hop taste coarser. When brewing light beers, it is recommended not to exceed 50 ppm, otherwise acid balance should be achieved by adding calcium to lower the residual alkalinity (RA) of the water. When brewing dark beers, some bicarbonate may be needed to compensate for the acidity of the dark malts. A high content of bicarbonates (and a strong alkalinity as a result) is undesirable for the wash water due to the increased possibility of silicates, tannins and polyphenols leaching into the wort from the malt. Controlling and adjusting the bicarbonate content of the water is important to achieve the desired pH in the mash.

Alkalinity can be roughly expressed from the concentration of bicarbonates if the pH of the water is less than 8.5. The formula below displays this relationship:

Alkalinity (ppm as CaCO3) = Bicarbonate(ppm)*0.83

2.5.5. acids

Acids can be an important component for adjusting the mineral composition of water. Acids come in solid and liquid forms, and all donate protons (hydrogen ions, H+) into solution and lower the pH. Acids also donate their anions to the solution. Often, these anions have their own specific tastes and odors, and accordingly, they are introduced into the beer when a certain threshold is exceeded. Some acids are more noticeable in beer than others.

phosphoric(Phosphoric) acid is the hardest to detect in beer, as it beer already contains these phosphate compounds. It is the most commonly used acid in the brewing and food industry in general due to its flavor neutrality.

Chloric And sulfuric acids can produce chloride and sulfate ions, which may be undesirable in a particular beer.

Lemon, apple And wine acids can bring a fruity and estery feel to the beer.

Dairy And acetic acids will give the beer its unique flavors. Dairy gives a soft and even sourness, while vinegar - caustic and spicy.

2.5.6. Less significant ions

There are less important ions in brewing that do not have such an impact on the result as described above. But some still have a beneficial or detrimental effect on beer depending on their concentration.

Potassium is a component of malt and is in any case introduced into the wort. The potassium content of water has some effect on taste, adding saltiness at high concentrations. More than 10 ppm of potassium in water can interfere with the proper functioning of certain enzymes. However, given the amount of potassium contributed by the malt, it is possible that a higher concentration of potassium in the water may be acceptable. Because Potassium is present in the malt, there is no need to add it to the water.

Zinc is an essential micronutrient for yeast at concentrations of 0.1 to 0.2 ppm. In amounts greater than 1 ppm it is poisonous to them. Zinc is present in malt in sufficient quantities, so there is no need to specifically add it to the water.