5 Written Questions
5 Matching Questions
- Staphylococcus aureus
- sand filters
- activated sludge tank
- acetic acid
- a clarified water aerated by injection of air. A way to add oxygen so that aerobic microbes will use up oxygen.
- b below -20C. Solutes in food depress the freezing point of water. Must have all water in form of solid ice. Can preserve food indefinitely. Some are killed by ice-crystals. Some are simply preserved
- c (species) Salt tolerant. Food poisoning in high salt food
- d Organic acids. Vinegar. Often added to veggies, meats, mayo (pickles)
- e Disinfection after secondary treatment depends on next use. Most effective way to remove giardia and cryptosporidium
5 Multiple Choice Questions
- peak efficiency of aerobic microbes in reducing organics. Secondary treatment.
- Organic acids. Produced by fermentation. Added to bread (Swiss cheese)
- A way to add oxygen so that aerobic microbes will use up oxygen. Water sprayed from rotating booming water trickles through deep bed rocks. Pick up oxygen on rock-layers (biofilm) of decomposers. Remove organics as water passes
- inverted by N.Appert, big prize from napoleon. Heating of food in bottles and seal it. Main concern now is growth from any surviving bacterial spores.
- (genus) bacteria associated with unpasteurized cheese and "pre-cooked meats"-hot dogs, deli meats
5 True/False Questions
flocculation → occurs throughout secondary treatment. Reduce pathogen by_________________
refrigeration → 0-4C. Slows metabolism and growth. Extend shelf life but not forever. Does create good conditions for psychrophiles. Ex) lactobacillus, listeria, pseudomonas
competition → 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'
nitrosamines → in body, we convert nitrites and nitrates to ______ which is CARCINOGENIC.
antioxidants → in body, we convert nitrites and nitrates to ______ which is CARCINOGENIC.