1. Food-BioTech @ KMU Alcoholic beverage “BEER”

2. Food-BioTech @ KMU Date created : B.C. 1400 ~ 1390 Located at Thebes, Egypt History of alcoholic beverage (B.C. 5000 ~)

3. Food-BioTech @ KMU  C 6 H 12 O 6 ( 포도당 ) 2C 2 H 5 OH ( 에탄올 ) + 2CO 2 ( 이산화탄소 )  Starch ( 전분 ) Glucose ( 포도당 ) Ethanol ( 에탄올 )  H 2 O (water) C 2 H 5 OH ( 에탄올, in Bible) Principles of alcohol fermentation

4. Food-BioTech @ KMU  Alcohol yield ( 수율 ) - Theoretical yield : 2 mol ethanol/1mol glucose 51.1% g ethanol/g glucose - Actual yield : maximum 95% of theoretical yield (5%  yeast cell growth, by-product formation)  Importance of fermentable sugars ( 발효성 당 ) - Ready to use : glucose, fructose, mannose, galactose - use after hydrolysis : sucrose, maltose - General yeast can not ferment polysaccharides such as starch and cellulose. In order to use, hydrolysis process should be required. Glucose (C 6 H 12 O 6 ) 2 ethanol (C 2 H 5 OH) + 2 carbon dioxide (CO 2 ) Alcohol fermentation

5. Food-BioTech @ KMU  Fermented chemicals affecting alcohol quality - Acetaldehyde * Contents : 20~40mg/L (sweet potato), 30~50mg/L (molasses) * Intermediate in alcohol fermentation. Its content decreases in maturation process - Diacetly * Content : ~10mg/L * Off-flavor in beer broth. * Produced together with acetoin and 2.3-butylenglycol by microbial fermentation - Methanol * Content : 0.70~0.11mg/ml * Made from pectin (cell wall) of beer sources * Present much in sweet potato broth. - Fusel oil * Content : 0.5~1.0 mg/ml * Higher alcohol : n-propyl alcohol (1~2%), isobutyl alcohol (10%), isoamyl alcohol (45%), active amyl alcohol (5%) * Trace elements : ester of higher alcohol, furfural, pyridine, fatty acid Alcohol fermentation

6. Food-BioTech @ KMU Process for beer making (Brewing)

7. Food-BioTech @ KMU  Definition in Korea Liquor Tax Law “ 맥아 및 홉 ( 홉 엑기스를 포함 ) 과 백미 ∙ 보리 ∙ 옥수수 ∙ 고량 ( 高粱 )∙ 감자 ∙ 녹말 ∙ 당질 ∙ 캐러멜 중의 하나 또는 그 이상의 것과 물을 원료로 발효시켜 여과 제성한 것 ” “The content of starch except for malt has to be controlled under 50% of malt weight.” “Alcohol content is more than 2 o and less than 6 o.” Definition of beer

8. Food-BioTech @ KMU  According to used yeasts 1) Top-fermentation beer (Ale beer) - Developed from United Kingdom. - Traditional beer. Containing various tastes and flavors - Type: ale, stout, porter 2) Bottom-fermentation beer (Lager beer) - Developed from Germany. - Modern beer. Bitter and cooling tastes - Tyep: Most beers (Germany, USA, Japan, Korea)  According to beer color 1) Dark beer: (Bottom) MünchenBier (Germany) (Top) Porter, Stout (UK) 2) Light beer: (Bottom) Pilsen, Dortmund (Top) Pale Ale, Mild Ale (UK) 3) Middle colored beer Classification of beer

9. Food-BioTech @ KMU (1) Malt ( 맥아 ) - Called germinated barley( 발아보리 ) - Hordeum distichum ( 두줄보리 ) is mainly used in Germany, Japan and Korea. - During germination of barely, amylase from barely hydrolyzes starch in barely.  Monosugars (glucose) from barely are used for yeast growth and alcohol fermentation. 1) Specification of barely for beer ① Thin hull, light brown color ② Over 95% germination rate ③ About 10% water content ④ high starch & low protein contents Raw materials for beer fermentation

10. Food-BioTech @ KMU 2) Process for making malt - Germination of barely - Affects the final quality of beer (Low quality of barely decreased the beer quality and reduced alcohol fermentation yield.) Barely selection Submerging Germination Drying Root cutting Malt Submersion in water to provide water for barely germinationand root growth Hydrolysis of most polysaccharides by enzyme activation atappropriate temperature and water content Removal of dirty materials, hulls and straws Prevention of more growth and hydrolysis of barely.Improvement of storage time, flavor and taste Removal of barely root containing bitter-taste proteins Raw materials for beer fermentation

11. Food-BioTech @ KMU Raw materials for beer fermentation (2) Water - Occupies about 90% of beer - A very important factor for beer quality. Its quality is suitable for beverage. - Minerals in water make an importance to enzyme action and fermentation. - For general light-color beer, water contains low contents of calcium, magnesium and carbonate.

12. Food-BioTech @ KMU (3) Hops ( 홉 ) - A mulberry ( 뽕나무 넝쿨풀의 열매 ) - Provision of bitter taste and traditional flavor to beer 1) Function ① Typical flavor and cooling tastes of beer ② Prevention of spoilage by other M/O’s growth ③ Improvement of foam quality of beer 2) Processed type - Hops are processed in order to make powder, extract, pellet types. - Maintenance of bitter-taste components and elongation of storage time Raw materials for beer fermentation

13. Food-BioTech @ KMU top-fermenting yeast ( 상면발효 효모 ) bottom-fermenting yeast ( 하면발효 효모 ) - Growth at 18~25 ℃ - Floating on the surface of beer broth accompanied by carbon dioxide production - Growth at 8~12 ℃ - Settling down during fermentation or at the end of fermentation - Able to use melobiose and raffinose, different from top-fermenting yeast S. cerevisiaeS. carlsbergensis & S. uvarum Raw materials for beer fermentation (4) Yeasts ( 효모 ) - One of the most important factor affecting beer quality - Generally Saccharomyces species 1) Function ① Production of alcohol and carbon dioxide gas ② Production of other nutrients such as flavors, vitamins and amino acids ③ Alcohol content and taste are decided. 2) Classification

14. Food-BioTech @ KMU - Milling raw materials - Mash making Boiling malt extract CoolingFermentation MaturationFiltrationBottling Process for beer making

15. Food-BioTech @ KMU Mash making Boiling Cooling Fermentation Maturation Filtration Bottling Process for beer making

16. Food-BioTech @ KMU Mash making Boiling Fermentation Maturation Filtration - Process : boiling the wort (malt extract) and adding hops - Purpose : deactivation of enzymes related to wort making and sterilization for fermentation - Addition of hop  By high heat, α-acid in hop is converted into isohumulone (bitter taste of beer) and extracted to the wort solution. Bottling Cooling Process for beer making

17. Food-BioTech @ KMU Cooling Fermentation Maturation Filtration - Principle : After boiling, wort solution is cooled from 90 o C to about18 o C. - Purpose : Temperature control for fermentation Bottling Mash making Boiling Process for beer making

18. Food-BioTech @ KMU Fermentation Maturation Filtration - Principle : Addition of yeast and fermentation of the cooled wort solution in a fermentation tank at 18~20 o C - Purpose : Fermentation of sugars to alcohol and CO 2 Production of flavor and taste components such as esters and higher alcohols (propanol, butanol, isoamylalcohol, etc.) - Process: For Ale beer, it takes about 2 weeks at 20 o C. Bottling Cooling Mash making Boiling Process for beer making

19. Food-BioTech @ KMU Maturation - Principle : Removal of the settled yeasts and maintenance of fermentation temperature at about 9 o C and more fermentation for 6 weeks - Purpose: For lager beer, additional fermentation of non-fermented sugars saturation of carbon dioxide in beer separation of precipitates refining raw taste and flavor making matured clear beer Fermentation Process for beer making Cooling Mash making Boiling Filtration Bottling

20. Food-BioTech @ KMU Filtration Maturation - Principle : production of clear beer solution by filtration utility - Purpose : removal of residual yeasts in beer, precipitated proteins and unstable components - Storage : analysis of beer quality Process for beer making Fermentation Cooling Mash making Boiling Bottling

21. Food-BioTech @ KMU Bottling - Principle : Addition of beer into bottle and covering Using the tested and sterilized clean bottles Filtration Process for beer making Maturation Fermentation Cooling Mash making Boiling

22. Food-BioTech @ KMU <Movie for home brewing ( 동영상 )> Process for beer making