5 Written questions
5 Matching questions
- nitrates and nitrites
- benzoic acid
- least sensitive
- a Range of radiation sensitivity: clostridium and bacillus (spores)
- b (genus) bacteria associated with unpasteurized cheese and "pre-cooked meats"-hot dogs, deli meats
- c pathogens are trapped in floc. They get killed by _________: intestinal microbes are not well adapted to this environment. Lose out by ____ for nutrients to "good bugs'
- d common in preserved meats such as bacon, pepperoni. KILL microbes (Cidal agent) like salmonella by inhibiting enzymes used in ATP productions. Preserve red color of hemoglobin.
- e Organic acids. Added to juices, jams, tomatoes, soda (salt)
5 Multiple choice questions
- (species) bacteria that grow in food, orginally from skin. Secrete toxin into food that induces vomiting and diarrhea. Self-limiting. Associated with SALTY foods.
- Organic acids. Produced by fermentation. Added to bread (Swiss cheese)
- end product of anaerobic sludge digester. Organics will be fermented or organic acids + carbon dioxide. It is then converted to _________ by methanogens.
- pathogens are trapped in floc. They get killed by _________: protozoans eat bacteria
- 0-4C. Slows metabolism and growth. Extend shelf life but not forever. Does create good conditions for psychrophiles. Ex) lactobacillus, listeria, pseudomonas
5 True/False questions
Radiation → permitted for some foods. Will sterilize but can/will cause chemical changes in food. Creates peroxides that degrade proteins. End product: NH3 and amines. Degrade fats, short chain fatty acids. Was concern might create carcinogen.
140C for 2 sec → ultra high temp. Usually sterilized milk, if sealed, don't need to refrigerate.
120C → canning temperature needed for high acid foods (pH<4.5). Kills all vegetative cells. If spores survive, can't germinate at low pH
Radiation → pathogens are trapped in floc. They get killed by _________: protozoans eat bacteria
100C → canning temperature needed for high acid foods (pH<4.5). Kills all vegetative cells. If spores survive, can't germinate at low pH