Alcoholic Beverages Flashcards
Define Beer
Beer is a term associated with non-distilled alcoholic beverages made from partially germinated cereal grains, referred to as malt.
What is included in this group?
These include ales, lagers and stouts, which normally contain 3-8% ethanol.
What are the ingredients?
The main ingredients are hops (giving beer the characteristic flavor and aroma), water and yeast.
How many stages?
4
What is stage 1?
Malting: the partial germination of cereal grain to form malt (6-9 days). This is the primary beer ingredient, it contains mainly starch. Malted barley , or malted wheat, or malted oats.
What is stage 2?
Mashing and wort preparation: the production of an aqueous fermentation medium, “wort”. It contains fermentable sugars, amino acids and nutrients. This is sterilized by boiling, and hops are added for flavor.
What is stage 3?
Yeast fermentation: selected strain of Sacchromyces cerevisiae, the wort undergoes an alcoholic fermentation, to produce ethanol, CO2, 2-7 days, depending on the beer produced.
What is stage 4?
Post fermentation: the fresh beer is subjected to various treatments to make it acceptable for the shelf.
What is wine made of?
Wine can be made from any plant extract or fruit juice that contains sufficient levels of fermentable sugars. However most wine is made from grapes, Vitis vinifera, which can be grown all over the world. The amount of wine produced all over the world, 1010 liters/yr.
What does grape juice contain?
Grape juice contains high levels of fermentable sugars, glucose and fructose, 160-240 g/liter.
What is the natural acidity?
pH 2.8-3.8 prevents spoilage from occurring
How much ethanol is in wine vs port?
Most table wines are 14% ethanol. Some regions fortify the wine with ethanol, sherry, port may be as high as 22% ethanol.
What kind of variety in wine?
Immense variety of wines, by color, sweetness.
What other factors influence wine?
Other factors that influence: specific grape variety, soil, climate, cultivation, grapes condition at harvest, grape must (destemmed, macerated, pressed grapes), fermentation, post fermentation treatments, maturation in the bottle.
How is alcoholic fermentation carried out?
The alcoholic fermentation of wine is carried out by indigenous yeast or added yeast. Done in a controlled cool setting, for every 10g/l of sugar fermented the temperature of the vat rises 1.3 C, therefore temperature control a must. White wine fermentation is maintained at 10-20 C, red wine maintained at 24-29 C.
What is whiskey made of?
made from malts except the wort is not boiled, no hops are added.
What is the primary fermentation of “sour mash” whiskey?
Lactobacillus delbrueckii, the lactic acid produced is 1.5% before being killed. The yeast used for fermentation is S. cerevisiae, distillation follows to increase the ethanol level. The distillate is colorless caramel coloring is added, maturation occurs in oak flasks, usually 40% ethanol at bottling.
How is the industrial process completed?
Stainless steel vessels, 250-100,000 gal. in size. These vessels are temperature controlled with jackets and controllers, pH controllers, aeration if necessary, nutrients are added at the beginning (batch), or throughout (continuous).
What does the culture medium contain?
carbohydrate, hydrolyzed protein, trace elements, and buffers.
How do they monitor the levels?
. Probes are in the tank to monitor temperature, oxygen level, pH, nutrients (if possible).
Why is carbon used?
Used in the fermentation process, is required for all biosynthesis leading to reproduction, it also serves as an energy source.
What is the biomass yield coefficient?
biomass produced divided by carbon substrate utilized
What are the culture methods?
Batch vs. Continuous
Liquid vs. solid
Immobilized microbial cells
How much is the industrial enzyme market worth?
$1 billion/yr
