April 7, 2010

Better Brewing Through Chemistry

Additive-free brewing is awesome and noble and delicious. But some chemical additives can make brewing life easier and more consistent.

Here are some additive products that I am a fan of:

Buffer 5.2:
Relax, don't worry, use Buffer 5.2.
Understanding pH and mashing isn't easy. Using Buffer 5.2 is. There are a bunch of enzymes in barley that do a bunch of stuff - which can get pretty confusing pretty quickly. The enzymes brewers are interested in all work at a pH level of 5.2, which makes this an ideal target for mashing. Through the use of some fancy salts, Buffer 5.2 overrides the buffering capacity of your barley and will help maintain this ideal pH level.
Buffer 5.2 can effectively increase efficiency, but you want to be very careful in measuring out the amount you use per the manufacturer's recommendation.

*How to control mash pH without buffering salts:
Phytase is an enzyme present in barley that will lower the mash pH by breaking down a compound called phytin into phytic acid. The enzyme itself works best in a pH range of 5.0-5.5 and a temperature range of 86-126 degrees F. A 30 minute rest at 95 degrees F can lower your mash pH. Or you can use a handful of acidulated malt in your mash.

Dimethyl polysiloxanes are cool. Fermcap-S is a polymer that reduces surface tension and so can be used in a boil to reduce risk of boilovers. Added to the fermenter, you reduce your krausen, which can help avoid blowoffs. I find this product particularly useful when fermenting 3 gallon brews in 3 gallon fermentation vessels.
Fermcap-S will bind to things like carrageenan, 3,beta-anhydrogalactose, and/or yeast membranes. So, if using Irish Moss in the boil, Fermcap-S won't carry over into your fermentation vessel; if using Fermcap-S in the fermenter it will be pulled out when your yeast flocculate which will leave no effect on head retention or flavor.
I would not use more than the manufacturer's recommended dose. I would keep this product refrigerated because this product degrades at 68 degrees over time.

*How to control boilovers without polysiloxanes:
Use a kettle large enough to allow for a full boil. Be careful when stirring in malt extract and hops. Establish a steady roiling boil, not a violent boil.
*How to avoid blowoffs without polysiloxanes:
Use a fermenter larger than your wort volume (i.e. - employ a 6 gallon carboy when brewing 5 gallons o
f beer).

Things that can cause haze include polyphenols, proteins, and yeast. Different clarifiers work differently and you must be very careful in the dosages you use.Try reading Chapter 5 of George Fix's "Principles of Brewing Science" for more information.
  1. Polyvinylpolypyrrolidone (PVPP): This is a clarifying agent that is polyphenol-active. Removing high-molecular weight polyphenols (tannoids) can reduce chill haze and increase the shelf life of a beer.
  2. Irish Moss (or Super Moss): This is a clarifying agent that is protein-active. Carrageenan and 3,beta-anhydrogalactose are the active compounds in Irish Moss and will bind to positively charged proteins in the boil kettle.
  3. Isinglass: This is a clarifying agent that is yeast-active. This compound only reduces yeast biomass and will not have any effect on chill haze.
*How to clear beer without using clarifiers:
Recycling wort through the grain bed in your mash tun will lead to clearer wort, but I don't recommend this practice as it can adversely affect yeast health (see my March 5, 2010 blog entry
"2 Things Literature Says You Should Do That You Shouldn't"). Ensure a good hot break (Boiler up!), ensure a good cold break (Use a wort chiller!), and choose a highly flocculant yeast strain.

Pectic Enzyme:
Sometimes, I like to use fruit in my beers. Before using the fruit, it is generally a good idea to treat it with Pectic Enzyme. As our website states, Pectic Enzyme physically destroys pectins, which constitute the "fleshy" part of most fruits. It will break down the pulp, making pressing more efficient and will aid in the extraction of tannin from the skins. It can also slake pectin haze. It does it's best work at 113-131 degrees F within a pH of 4.5-5.5, so add a gallon of liquid that isn't just water (use your beer if you are making a fruit beer and use your honey if making a melomel) to your fruit and 0.5 tsp pectic enzyme. Heat to 122 degrees F. Hold it at 122 degrees F for 45-60 minutes without stirring. Don't worry about driving off alcohol or ruining your beer/mead/bourbon/whatever. Alcohol boils at 174 degrees, so you won't lose it. And the vapor heat will keep a few molecules of gaseous water between oxygen in the air and the surface of your beer. Reserving the squeezed solids for making ice cream or jam or marinades, return the entire liquid portion to the fermenter (but cool it first).

*How to use fruit without pectic enzyme:
I don't recommend using fruit without using pectic enzyme.

This is a compound that interferes with the production of protein in brewing yeast. If you are trying to ferment with or harvest wild yeast, this compound will inhibit the growth of domesticated brewing yeasts yet allow for the growth of the wild beasts.

*How to harvest wild yeast without cycloheximide:
Set out a cup of sterile starter wort (OG 1.020) open to air and wait for things to start growing in it. Then set your cup in the fridge to cold crash whatever the living organism is. Decant your wort, add V8 juice to the yeast and swirl. Examine your yeast under a microscope and look for pear-shaped things. These are sporulating yeasts and are called schmoo (domesticated brewing yeast have lost their ability to sporulate and will appear as round shapes). V8 juice is high in acidity and low in carbohydrates, so you will shock and starve your yeast. Brewer's yeasts are wussies and won't be able to handle an extended period in such conditions, but wild yeasts are prepared to handle this stress. Cold crash your yeast, then wash them with acidulated wort (pH 3.5) and pitch them into a small starter (300mL, OG 1.020, pH 5.8) and step them into a higher gravity wort (300mL, OG 1.040, pH 5.8) and then into a larger volume (600mL, OG 1.040, pH 5.8) and then into an even larger volume (1.2L, 1.040, pH 5.8).


Heat your infected wort to 126 degrees F and hold for 15-20 minutes. This will kill your wimpy domesticated brewing yeast but your robust rebellious wild yeast will survive.

Add some science to your art!

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