Bruce V. Hofkin
Living in a
Microbial World
Chapter 15
Guess Who’s Coming to Dinner:
Microorganisms and Food
Copyright © Garland Science 2011
Belgian Trappist ale
larger beer
Saccharomyces spp.
wild yeast
The beginnings of a beautiful friendship
Food preservation by microbial activity
food spoilage
some spices inhibit microbial growth
fermentation- food spoilage 저해
Fermented dairy products and grains
milk -> yogurt from Central Asia
cheese 8천년 전 Middle East
->Greece -> Rome
alcoholic beverages
BC4000 Sumerian- wine, beer 생산
bread –Middle East
Microorganisms and food production
Fungi and bacteria as food
mushroom – fruiting body of some fungi (주로 Basidiomycetes)
Vegemite – extract of Saccharomyces cerevisiae, vegetabler flavorings and spices
- invented in 1922 by food technologist Dr. Cyril P. Callister in Autralia
single cell protein- yeast 등, 영양가 향상, 고 핵산함량- gout (통풍)
cyanobacteria Spirulina – Chad에서 dihe- 음식 첨가물로 이용
Fermentation
definition
fermentation products- food preservation, new desirable flavors and aromas
Fermentation of plant products
Bread
substrates- sugar
Saccharomyces cerevisiae – baker’s yeast (dry yeast)
glycolysis -> CO2, ethanol and others (flavor)
sourdough bread 제조 시- yeast와 lactic acid bacteria
Wine
포도 -> must – SO2로 살균
red, rose, white wine
Saccharomyces cerevisiae- brewer’s yeast
fermentation
alcohol content- 7-18%
aging
filtration / pasteurization
bottling
sweetness/alcohol content
Champagne/sparkling wine
-fermentation after bottling
wine making is both a science and an art.
- oenology
Beer
malting(맥아제조)- substrate barley- saccharification
보리 발아-> malt 건조, 볶음, 물 첨가 – mashing (담금)
wort (맥아즙, 맥즙)에 hop 첨가
boiling
liquid wort 분리 후 Saccharomyces 첨가- 발효
S. carlsbergensis – larger or pilsner beer, bottom termentation
Pilsner Urquell- Plzen
S. cerevisiae – ale beer, top fermentation
alcohol content 3.5-6%
filtration/pasteurization
carbonation
bottling
Liquor – distilled alcoholic beverage
higher alcohol content and flavors
source of sugar - single malt whisk(e)y, blended whiskey
vodka, rum, tequilla
Liqueur – 혼성주, 재제주
Other fermented plant products
pickling
lactic acid bacteria – Leuconostoc, Lactobacillus, Streptococcus spp.
sauerkraut, pickle, olive, kimchi
Flavoring agents
vinegar
- acetic acid bacteria (Acetobacter)- strict aerobic, oxidation not fermentation
- meaning of fermentation- biological, industrial
- common source of ethanol – fermented apple juice, beer, wine
soy sauce
- soybean and wheat- Aspergillus 발효 후 salt-tolerant bacteria and yeast
citric acid
- Aspergillus niger 당밀 분해, 포도당 과당,
구연산 생성
Fermented milk products
Russia-koumiss, Mongolia-airag 마유주, Kazakhstan-shubat 낙타
Yogurt
- Streptococcus thermophilus, Lactobacillus bulgaris
- lactic acid 단백질 변성, 응고, 기타 flavors
- homolactic, heterolactic fermentation
Cheese
- types (moisture content, substrate, fermentation, microbes etc.)
- 제조 방법
curd(응유) 생성- 유산균, clotting enzyme rennin (송아지 위장, 현재는 세균에서 합성)
whey(유청) 제거, pH 염도 수분함량 조절 후 성형- 미숙성 – cream cheese, cottage cheese
aging – 세균과 진균 대사산물- 다양한 flavor, aroma, texture
white mold cheese Brie Penicillium candidum, Brevinacterium linens
Camembert Penicillium camemberti
blue mold cheese Penicillium roqueforti
hard cheese- 1년 이상 숙성,
Swiss cheese Propionibacterium
Fermented meat products
summer sausage, salami- bacteria 접종
cured ham – fungi
fermented seal flipper in Alaska
-Clostridium botulinum 오염 가능성
fermented fish sauce (젖갈)
Production of other foods and dietary supplements
Coffee bean- pectin 외피 Erwinia dissolvens - pectinase 이용 분해
Dietary supplements
-vitamins – 세균과 진균 대사, 합성, bioconversion
-amino acids
NutraSweet® - aspartame- asparagine, phenylalanine, 설탕의 200배 당도
lysine – 식품, 사료 첨가제, Brevibacterium
glutamic acid- MSG
-probiotics- product consisting of living bacteria promoting overall health
음식 소화, 생리활성물질 (항암성분 등) 생성 등의 효과- 많은 경우 아직 작용방법 불분명
Time to eat
sauerkraut, pickle, baggle, yogurt, feta cheese, Vegemite