Why Boiling Wort Is Essential: Transforming Good Beer into Great Brews!

Boiling wort is one of the most critical and complex aspects of the brewing process. Many new whole-grain beer brewers read about the effects of different temperatures, mash thickness, and other aspects of boiling to understand what happens during the boiling process and how to deal with it.
Boiling is one of the standard steps of the brewing day, so much so that the time interval for adding hops and the boiling temperature is indicated in many brewing recipes. It may take 90 to 120 minutes to boil for Grist that uses a lot of Pilsner malt. Boiling is an important stage that every beer must go through from grain to beer. This is why it deserves your attention.

What is wort?

First, let us first understand what wort is. Wort is a brewing term that essentially refers to unfermented beer. For brewers, it is very important to understand what wort is and how it affects the beer brewing process.
Many complicated reactions occur before the beer is fermented. This is also the process by which wort turns into beer. Everything about beer starts with making wort, which gives the beer a basic flavor, including the types of grains and hops required by the brewer’s recipe. Wort is a sweet liquid and contains a lot of starch. Boiling is adding hot water to the wort, allowing enzymes to degrade starch into monosaccharides that can be fermented. This is also an important function of the boiling process. Let’s take a look at the benefits of boiling wort.

Sterilize wort

When selecting malt and preparing wort, some microorganisms will enter the wort. When you mash and lauter, the temperature usually doesn’t get above 78°C (for mash out). This temperature isn’t high enough to “inactivate” some of the microbes in the grains, hops, and adjuncts used in brewing.
We need to ensure as much as possible that yeast is the only thing that grows in beer. Boiling wort can kill any microorganisms that may be present in the wort or other ingredients. In the first 15 minutes of boiling, most of the bacteria in the wort will lose activity. In addition, when you add hops to the wort, the pH in the wort will drop, which also helps the sterilization process.

Stop enzyme activity

The action of most enzymes stops very early in the wort collection process, and we need to ensure that the ingredients in the wort are fixed before the fermentation process. And boiling can inactivate the enzymes in the wort and fix the carbohydrates in the wort, so as to achieve a fixed dextrin content in the final beer. Dextrins are complex carbohydrates. If there is no enzyme to break them down into simpler sugars, yeast cannot ferment them. In addition, brewers can control the ratio of fermentable and non-fermentable sugars, taste, and other factors by controlling the wort.

Hop's alpha acid isomerization (extract bitterness)

The substance responsible for increasing bitterness in hops is called alpha acid. But normal alpha acid will not bring a bitter taste to the beer. Only alpha acid undergoes isomerization (change in chemical structure) to bring a bitter taste to the beer. Therefore, if the alpha acid, which is so precious in hops, is not boiled well, it is almost useless. Boiling will help the isomerization of alpha acids, making it easier for iso-alpha acids to dissolve in the wort.

Evaporate

Raw materials such as barley contain volatiles and need to be boiled to remove them. If you don’t boil it, your final beer may have a peculiar smell. One of the main sources of peculiar smell is DMS (dimethyl sulfide).
Dimethyl sulfide-If you have ever smelled the aroma of corn in beer, then you have encountered DMS. In light beer and lager, ordinary drinkers can detect it at very low levels. In addition, the precursor of DMS is SMM (S-methyl methionine), which is produced during the sprouting process of barley. When you heat the wort, SMM decomposes into DMS. However, in the case of violent boiling, DMS will evaporate and take most of it away. If you are interested in how to deal with DMS, you can read our “Guide to beer off-flavors: DMS” article.
Boiling also removes the volatiles contained in unwanted malt and hops, which can also have a negative impact on the final beer. In addition, adding hops at a later stage (close to the end of boiling or after stopping) will retain the aromatic hydrocarbon components in the hops in the wort and improve the aroma of hops in the finished beer.
After you filter the wort and send it to the brewing pot, you need to add more water to ensure that as much sugar as possible can be extracted from the wort. But please be careful not to over-boiling and keep the final operation above 2.5 Plato (1.010 SG) to ensure safety. Otherwise, you may extract tannins and cause unpleasant bitterness in the beer.

Wort concentrate

Under normal circumstances, the wort collected after mashing will not have the original gravity expected by the winemaker. Therefore, by boiling the wort and knowing the boiling rate, the brewer can perform accurate raw gravity for his beer. In large breweries, as much as 10% of the contents of the kettle may be lost due to evaporation during the normal duration of boiling, which in turn increases the original specific gravity of the wort. This is important when brewing high-strength beers (such as barley) that are made only from grains. In order to achieve high virgin gravity, the wort is boiled for a long time—usually as long as three hours.
Please note that if you need to concentrate wort, you can do this by boiling the water in the brewing pot. The typical evaporation rate is 5% to 10% per hour, and most brewers have an evaporation rate of about 8% per hour.

Coagulate protein

There are many substances in malt, especially proteins, which are suspended in the wort. If you want to produce beer that feels, stable and consistent, it is crucial that the protein solidifies and precipitates during the boiling process. The boiling process helps these proteins to condense into larger pieces during the hot rest and settle to the bottom during the cold rest. If you see “big fluffy bits” in the wort at the beginning of boiling, then you are doing the right thing.
Why does this happen? This is because, during the boiling process, proteins are denatured by heating, pH changes, oxidation/reduction (sulfhydryl groups), and hydrogen bonds with polyphenols. The protein changes from hydrophilic (attracted and dissolved by water) to hydrophobic (not attracted) and has a positive charge. Then they combine with negatively charged polyphenols and supplemented with some carbohydrates to form “big fluffy bits”. Next, the protein will fall off the wort and form part of the residue, which will not be carried to the subsequent fermentation tank.

Maillard reactions and color picking

The color of the wort in the kettle is a combination of many factors. The sugar in the wort caramelizes when it is boiled and darkens the wort when it is boiled. The chemical process that causes these changes is called the Maillard reaction.
Maillard reactions are non-enzymatic browning that adds color and flavor to the beer during boiling. It is a chemical reaction between the carbonyl group of an active sugar and the amino group of amino acids. There is a lot of science to explain this reaction. However, it is important to know that the final product of the Maillard reaction is melanoidin (brown nitrogen-containing polymers). When you boil the wort, it produces a deeper color.

Decrease in pH

When the wort is boiled, the pH will decrease. This is mainly due to the precipitation of calcium phosphate. The calcium ions in the brewing water react with the phosphates in the malt to form calcium phosphate and hydrogen ions, thereby lowering the pH of the wort. For most beer styles, you want the pH after boiling to be between 5.0 and 5.2. This is because:

Improved the characters extracted from the jump addition
Improve thermal rest
Reduce overall color pick-up

In addition, hop isomerization is also affected by pH. The higher the pH value, the better the conversion rate to iso-α acid. If the pH of the wort is between 8 and 10, you can achieve a conversion rate of up to 90%. However, the pH value of wort is usually between 5.2 and 5.4, so the conversion rate is low, usually, the upper limit is about 35%. Even if the conversion rate is low, it is better to have a lower pH due to the above reasons, and at a higher pH level, the characteristics and bitterness will be “coarser”.
In addition, thermal fracture formation is better at lower pH values, and 5.2 is the best value. If you see “big fluffy bits” in the wort, you will know if you are in range when the boiling starts.

Additives in boiling

When you boil the wort in the brewing pot, you can also add other ingredients. When the wort gets hot and boils, it is easier to add, mix, dissolve and sterilize these ingredients. In addition, you can add more kettle additives when boiling, which is very helpful for brewers.
What can you add when boiling? This list is very long, and we cannot list them all here. However, we need to talk about the first Irish moss.

Irish Moss

Irish moss is made from a blend of processed seaweed. When added to the boil, it helps your finished beer become “light”. The three main sources of beer turbidity are:

Tannin
Excess protein
Yeast

Now for Irish moss, we will focus on tannins and excess protein related to mashing and boiling. Tannins are naturally present in the barley husks released during the saccharification/filtration process. Protein is also found in cereals, especially wheat, oats, and barley flakes. Adding Irish moss in the last 15 minutes of boiling will help remove these. In short, it accelerates the coagulation of protein at the end of boiling and prevents cold mist.

Defoamer

Some brewers like to add defoamers when boiling to prevent boiling, thereby making the brewing safer. Adding these specially designed products will not affect the head retention or beer foam in the final product.

Yeast Nutrients

There are many different versions of yeast nutrition, some are added when boiling, and some are added after boiling is stopped. They can be used to help ferment high-strength beer or to help other products (such as hard soda) ferment.
A tip from an old brewer: If the yeast is used up, please use some yeast in the fermentation vessel and add it towards the end of the boil. It will help to add nutrients to the yeast that will be placed in the fermentation tank later.

Other clarifying agents

There are other products that help improve colloidal stability when added to the boil. These substances are particularly useful in heavy hop beer. There are even PVPP products that you can add to combat the cold haze.

Lactose and other sugars

Lactose is a processed sugar derived from milk. Ordinary brewer’s yeast cannot be fermented, but other yeasts such as Brettanomyces clause ii can ferment. It is used by beer manufacturers in sweet stouts and other beers to contain more residual sugar in the final beer.
Other sugars you can add to the boil include corn syrup. Some brewers use it to increase the original specific gravity and overall %ABV (alcohol content) of the final product. This is especially convenient if you have limited space in your mash and/or filter barrel and need a lot of abv beer. Adding sugar when boiling makes it easier to mix with the wort.

Other spices and fragrances

There are many other ingredients that can be added to the boiling as a winemaker. Usually, they are added at the end of boiling or after the flame is turned off. Here are just a few:

Orange peel — used in some Belgian smart beers.
Heather and ferns — used to brew in Scotland before the discovery of hops, some newer breweries are returning to use these ingredients.
Coffee — Most brewers will add coffee later, but I heard that some brewers use coffee when boiling.
Tea — You can add a lot of tea while boiling. However, be careful with tannins. If you are not careful, your beer may get an unpleasant astringency from the tea!
Spices — Another ingredient commonly used in Belgian wisdom is coriander seeds. They exude a spicy taste that complements the orange peel. Many different flavors can be used, such as cloves, which are commonly used in “Christmas” beer.

To be honest, you can add a lot of flavor and aroma when boiling. Just perform due diligence to ensure that anything you add is safe to eat.

Conclusion

So, you know, “Why do we cook wort” has many levels? I hope this article is informative and will give you a deeper understanding of what happens during the boiling process. As you can see, many important reactions and physical changes are taking place. From making beer more “storable” and concentrating wort to adding hops to increase bitterness and aroma.
The best way to improve beer over time is to record as much data as possible before, during, and after boiling. These can include:

Pre-boil pH & gravity
Post boil pH & gravity
The hot break can be measured in a graduated glass cylinder, even keeping a photograph on file
Evaporation rate – volume before and after the boil
If you’ve control of the steam then the percentage open of the steam valve during boil can be recorded as well

Keeping these files and recording all the information that happened during the brewing process can help you better analyze the brewing process and improve the brewing recipe. Of course, it can also help you understand where problems occur in the brewing process so that you can more easily solve and correct any problems.

Beer Brewing Equipment

Beer Brewery Equipment Manufacturer The brewing supplies provided by Micet Craft can support your brewing needs from small batches of micro beer brewing equipment to 100 barrels capacity. Micet Craft has reached cooperation with many breweries around the world, we can design and manufacture professional brewing systems for breweries, including cellar beer brewing equipment and other

Fermentation Tank

China stainless steel fermentation vessels manufacturer The fermentation tank is where the beer carry out the fermentation process, it provides a place suitable for life activities and metabolism for microorganisms. To adapt to the use of different sizes of breweries, Micet Craft produced a variety of sizes and specifications of fermentation tanks. Customers can choose

Bright Beer Tank

Professional bright Beer tank manufacturer from China The bright tank is a vessel for storing and carbonated beer, it is also called the brite tank. The bright tank is an important part of the workflow of professional beer brewers. It can be used to store and carbonate beer, thus eliminating the trouble of cleaning beer

Brewing Equipment

China brewing equipment manufacturer and suppliers Micet Craft has cooperated with breweries in many countries around the world to provide them with brewing equipment. We provide customers with turnkey brewery solutions, which include designing, manufacturing and installing customized breweries. The Micet Craft team has decades of experience in the manufacturing of brewing equipment, we not

Can regular dish soap be used to clean brewery equipment?

Brewhouse Equipment

Best brewhouse equipment manufacturer from china Brewing good beer requires brewhouse equipment. Whether you are brewing beer for home, business or brewery, Micet Craft can provide a turnkey solution according to the daily output you need. We have brewhouse equipment with 2 vessels, 3 vessels and 4 vessels, the unique design allows you to do decoction

Beer Filling Machine

Professional beer filling machine manufacturer Beer filling machine is the core equipment of the beer production line. Our beer filling system uses stainless steel as the production material. Stainless steel is not easy to wear, and it is easy to clean. Micet Craft provides you with a cheap and efficient way of filling beer. We

Beer Brewing System

Best beer brewing system manufacturer from china Micet Craft is a professional beer brewing system manufacturer in China. We mainly produce high-end customized turnkey brewing systems. Whether you are planning to open a nano-brewery, microbrewery, or commercial brewery, we can provide you with the most complete turnkey solution. Our beer brewing systems are all price-competitive