5 Written questions
5 Matching questions
- 72C for 15 sec
- benzoic acid
- Listeria monocytogenes
- a high temp, short time (HTST)
- b (species) bacteria can grow at cooler temperature (psychrotrophic). Grow at fridge and body temp. Will cause infections and kill white blood cell. Eventually can reach the brain, can cause placenta. High mortality
- c in body, we convert nitrites and nitrates to ______ which is CARCINOGENIC.
- d Organic acids. Added to juices, jams, tomatoes, soda (salt)
- e pathogens are trapped in floc. They get killed by _________: protozoans eat bacteria
5 Multiple choice questions
- Organic acids-often naturally produced in fermented foods. Foods naturally preserved. (cheese)
- Disinfection after secondary treatment depends on next use. Most effective way to remove giardia and cryptosporidium
- (species) Salt tolerant. Food poisoning in high salt food
- End of water treatment process is left with __________. Very slow to decompose. Not likely to create big problems, can be buried in landfill. Could improve soils, but depend on what is in it.
- Range of radiation sensitivity: Pseudomonas
5 True/False questions
aerobic → secondary treatment. Manipulate the environment to promote growth of microogranism that degrades organics. Use ____ microbes to produce carbon dioxide and water.
90-95% → peak efficiency of aerobic microbes in reducing organics. Secondary treatment.
140C for 2 sec → high temp, short time (HTST)
antioxidants → chemicals added primarily to stop chemical oxidation. Stop oxidation of fats that yields short chain fatty acids (odor, taste problems). May also have anti-microbial activity.
sorbic acid → Organic acids. Added to fruits, margarine, meat