Monday, July 15, 2013

A Window Into Recipe Design

For as much as I love to drink beer, brewing proves to be even more entertaining.  Recipe design is by far the most interesting element of the brew process.  It's similar to cooking in a way; you have to research and balance ingredients in just the right measures in order to come out with something truly great.  Like cooking, the number of ingredients are really limitless, but there are the main four: water, barley, hops and yeast.

Water is the base for all beer, and all food for that matter, and is very important in how your brew turns out.  However, changing your water is a complex process.  You need to get in depth information about your tap water and its chemical composition, and adjust your water profile accordingly by adding small amounts of various types of compounds depending on what you are brewing.  This is a necessity for commercial brewers, but lies on the extreme end of a homebrewers capabilities.  The most important part is that your water has a moderate pH, is not heavily chlorinated, not softened in your home and does not contain any extreme amounts of any particular element (most major cities water profiles are acceptable).  I do not alter my water profile for brewing.

Barley malt will form the next most important part of your beer.  Grains provide the sugars that the yeast will ferment to produce alcohol: more grain per batch will result in more sugar, which will result in more alcohol. The quantity of sugar in a beer is measured by SG or specific gravity; the alcohol content is based on the difference between your original gravity (the amount of sugar in your unfermented wort) and your final gravity (the amount of sugar in your finished beer).  The amount of sugar any given grain provides is measured in p/lb/g or points per pound per gallon: high p/lb/g grains add more sugar in the form of SG points, and thus result in more alcohol.  Grains also dictate mouthfeel, head stability and provide the malt aromas to your brew (such as caramel, biscuit, coffee, chocolate, nut and charcoal).  Grain selection will decide the color of the finished product as well, the darkness of the roast will tell you what color a grain will give your beer, the quantity of that malt you use will decide how much of that color it will add.  The roast of a grain is measured in degrees Lovibond (L), higher numbers are darker.  The color of a finished beer is generally measured in SRM (standard reference method), again, higher numbers are darker.  All these factors will help you decide what grains you want, and how much of each to use.

Hops are beers natural seasoning.  Their main usage is to provide bitterness that will offset the sugary tastes provided by the grain.  Bitterness is provided by the Alpha Acids in hops, or AA%: hops with a higher AA% are 'more bitter'.  The bitterness itself is measured in IBUs (international bitterness unit).  The relation between your original gravity and your IBUs is very important, it is called your OG:BU ratio.  A high ratio is a very bitter beer (an IPA for instance).  Hop utilization is also important.  Because your hops are boiled, their flavor and aroma dissipates as you boil them.  Hops boiled for 60 minutes or longer only contribute bitterness: no flavor or aroma.  Those boiled for 30 to 59 minutes add flavor (remember flavor is sensed by your tongue, and only comes in 5 variations). Those boiled for less than 29 minutes add aroma (those are sensed in your olfactory, and are the things you can name when you taste).  Different hops contribute different aromas, including citrus, pine, spice, earth, licorice, mango and even grape.  What aromas you want decide what hops you will use.  In general, cheaper, less unique hops are added early in your boil to supply the bitterness, and the more expensive and uniquely aromatic ones are added closer to the end to provide their distinctness.

Yeast selection is one of the most underrated parts of brewing.  Most people know they need to select a Lager strain (one that ferments on the bottom of the beer and works well when at cool temperatures) or an Ale strain (one that ferments on top, and works well when warmer).  What they don't know is that there are millions of sub strains of beer yeast, each that has it's own living preferences and develops different flavors.  I only produce Ales for right now, as the equipment you need to ferment them is minimal.  Careful yeast selection will help you develop the right flavor profile for your beer, or lack thereof.  It will determine the temperature you ferment at, how long you ferment it for, how clear your beer is and how much sugar your beer will lose to its 'appetite'.  Belgian style yeasts are notorious for liking high temperatures and consuming a lot of sugar.  American yeasts are known to clear up very well and produce minimal yeast flavor.  English strains can leave behind a lot more sugar than other yeasts, resulting in more body in the finished beer.  German Weizen yeasts throw off lots of citrus, banana and clove flavor.  Catering to your yeasts habits will allow it to really shine, and gives the best chance of it providing the elements that it is supposed to.

There are a million other things to add to your beer!  Sugars can be added to produce more alcohol and provide the sensation of dryness.  Grains can be varied to cut costs and change mouthfeel: corn is cheap and oats provide a full body.  You can add fruit, spices, clarification agents, yeast nutrients and energizers, or even foreign bacteria such as those found in yogurt or sourdough bread!

Recipe design is fun, experimental and painfully based on the trial and error process.  Give something a shot: if you like it, great; if you don't, change it.  Rinse and repeat.  Next up I'll be brewing a traditional Belgian wheat beer, called a Witbier, and in the spirit of summer I will be spiking it with fresh peaches.  I will be posting my recipe creation process for all to see, so consider this your primer lesson!

No comments:

Post a Comment