5 Written questions
5 Matching questions
- 140C for 2 sec
- Listeria monocytogenes
- bacillus cereus
- Trickling filter
- a (species) bacteria that will grow in food. Secrete toxin. Causes vomiting, diarrhea. Source: soil bacteria in dust.
- 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 ultra high temp. Usually sterilized milk, if sealed, don't need to refrigerate.
- d 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
- e end product of anaerobic sludge digester. Organics will be fermented or organic acids + carbon dioxide. It is then converted to _________ by methanogens.
5 Multiple choice questions
- Organic acids. Added to juices, jams, tomatoes, soda (salt)
- high temp, short time (HTST)
- Organic acids. Added to fruits, margarine, meat
- canning temperature needed for high acid foods (pH<4.5). Kills all vegetative cells. If spores survive, can't germinate at low pH
- 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
carbon dioxide → Organic acids. Added to fruits, margarine, meat
nitrates and nitrites → in body, we convert nitrites and nitrates to ______ which is CARCINOGENIC.
aerobic → canning temperature needed for high acid foods (pH<4.5). Kills all vegetative cells. If spores survive, can't germinate at low pH
Staphylococcus aureus → (species) bacteria that will grow in food. Secrete toxin. Causes vomiting, diarrhea. Source: soil bacteria in dust.
stable sludge → 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.