Happy Thanksgiving

Right-click to download MS Word File

Lecture 12 - Ingredients for Beer
 

Objectives

•      Describe the types of grain suitable for beer

•      Identify the growing conditions for grain

•      Define the types of yeast used for beer

•      Describe the use of and growing conditions for hops

Definition of beer

•      Beverage made from fermented grain

•      Simplest beer consists of: Grain (where starch has been converted to sugars), Water & Naturally occurring yeast

•      Beer may contain other ingredients, such as Roasted grain, Herbs, Hops, & Fruit

•      Typically 5-6% alcohol

History of purposeful grain growing

•      First farmer-brewers were in the Middle East, in the fertile crescent (now Egypt - Iraq)

•      Oldest known site is Jericho (Jordan), 10,000 BC

–   Non-brittle wheat (not native to the area) is found at greater than natural amount

–   By 4000 BC, rice grown in southern China,

–   BY 3000 BC, grain growing common worldwide

Grain qualities needed to make beer

•      Easy to grow, High starch content, Easy to convert starch to sugar, mold resistant

Grains used for beer

•      Barley, Wheat, Rice, and Others (rye, corn, millet) – Barley offers many advantages

Barley arose from wild grasses, Hordeum spontaneum

•      By earliest writings, brewing was well established

•      Goddess of brewing was Ninkasi

•      Different varieties with unique properties

•      Valued over wheat or rye because: Shoot develops inside grain, Rapid germination response to warmth, Protective husk prevents mold, Husks aid in filtering beer

Barley characteristics

•      Hardy, Can grow from Arctic Circle to tropics and is adaptable, Salt tolerant, requires only moderate moisture, Ripens faster than wheat, & Prefers a cool ripening season

Several Types of Barley

•      2 row - Hordeum distichon, widely grown; used for ale and better lagers

•      4 row - cold tolerant; not suitable for beer

•      6 row - Hordeum vulgare, warmer climates; used by largest breweries, higher protein can lead to beer haze

Barley growing regions

•      2 row: Pacific NW and northern half of Great Plains; used for both Feed and malting

•      6 row: Group 1 - bearded, upper Midwest, spring planted; used for malting

–   Group 2 - coast, winter or fall;  Group 3 - TN, feed

Requirements for best barley

•      Low moisture content, Few broken grains, No fungus burden, High proportion of starch to protein, and a Mealy, opaque appearance

Wheat

•      Initially 2 types known: Einkorn-Triticum monoccum & Emmer- Triticum dicoccum

–   Now >30,000 varieties

•      Wheat beers have thick mouth feel and strong head

•      Commercial wheat in US is planted either winter or spring

•      Wheat can be hard or soft - 90% of world production is soft

–  Hard has higher protein content and is good for pasta and bread

–  Soft is good for cake flour, bread and fermentation

Rye - Very cold tolerant, Will germinate at 33° though prefers 50°, Grows on land too poor for wheat, and Gives beer spicy flavor

Rice

•      Categorized by grain size - long, medium or short

•      Makes rice beer (malted) or saki (unmalted) which is often mislabeled as rice wine

Other grains

•      Millet - often used in Africa

•      Spelt - lighter in flavor than wheat

•      Oats - smooth, sweet flavor (oatmeal stout)

Water

•      So important, brewers refer to water as “liquor”; Mineral content greatly affects quality

•      6 main component salts:

–   Bicarbonate, sodium, chloride, calcium, magnesium, and sulphate

•   Proportions of these can greatly affect flavor and final color of product

–  High bicarbonate ® high acid mash  ® poor rate of sugar extraction of malt

–  Too much sulfate ® sharp bitterness

–  Calcium increases sugar extraction

–  Magnesium is an essential nutrient for yeast

•      Many brewers boast about water “purity” (e.g., Coors)

•      1L of beer takes 5L more for cleaning & cooling

Yeast (Saccharomyces)

•      When first begin brewing, relied on wild yeast; Could only brew in Fall & Winter

–   Left their brew in open vessels, in which airborne wild yeasts settled

•   The brew foamed, fermented, turned into beer

–   Brewers didn't realize that the foam on top contained millions of yeast cells

•   Did learn to scoop off foam and use it as a starter for the next batch

•   Empirically, they were breeding, by selection, top-fermenting yeasts

–   Top-fermenting yeasts à ale (S. cerevisiae)

•      When monasteries spread north across the Alps, the cooler climate favored barley and beer over grapes and wine

–   On hilltops, they carved beer cellars into the rock beneath and packed with ice

–   When stored (or "lagered") in such cold temperatures during the summer months, the beer became inherently more stable

–   Yeast sank out of harm's way; empirically, they were breeding bottom-fermenting cultures

•      Bottom-fermenting yeasts à lager (S. carlsbergensis)

Hops - Humulus lupus (like a wolf among scrubs)

•      Known in Roman times as medicine; Still used to treat sleeplessness in Europe

•      Records from 822AD suggest monks added hops

Hops cultivation

•      Vines grow to 20’ each year from perennial vine; Need deep soil (at least 6’)

•      Grow in Germany, northern US, UK, Belgium

•      Cones of female flower produce yellow resin, called "lupulin"

–   Characteristic bitter flavor – from iso-a and b-acids

–   Over 250 flavor compounds

–   Anti-microbial

•      Cones may be dried and baled, or be processed even further by grinding to a powder or even extracting the lupulin

•      Different varieties of hops ® different beer flavors

–   American hops more citrus & pine than European hops