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Sources of MOs
Most food tissues are internally sterile (Meat, fruits, veggies) Internalization is most likely due to injury by insects/machinery, needle tenderization (steaks) Natural sources of MOs on Fruits/Veggies: Surfaces, pores Animals: hide, feathers, fecal/intestinal tract, respiratory tract External sources of MOs Air, soil, sewage, water, feed, pests, human, harvesting/processing equipment TERM 2
Predominant MOs on Plants
DEFINITION 2 Exposed, porous surfaces interact with air, water, and insect/animal pestsMolds, yeasts, lactic acid bacteriaSewage/water, raw manure, animal feces, flies/insects, rodentsSurface/biofilms, Internalization Stomata openings, insect injury, root uptake TERM 3
Predominant MOs on Seafood
DEFINITION 3 Also carry an associated flora on skin, scales, intestinal tractsWater quality, feeding habits, diseases can affect presence of orgsHave specific MOs associated with them. Vibrio Cholera TERM 4
Predominant MOs on Animals, Poultry
DEFINITION 4 Hair/hides/skin/feathers/fecesGastrointestinal contents, other tract openingsMastitis (cow udders), urogenital/uterine infectionsCan harbor GI tract pathogensAlso contaminated with yeasts and moldsListeria has been isolated from many, many animals TERM 5
Predominant MOs in Air
DEFINITION 5 Dust, MOs are easily distributed by air currents, velocityPresence may be dependent on resistance to dryingDust: yeast, molds, spores, Gram+ bacteriaWater droplets - big problem with blast chillers in processing areasMOs may grow in liquid if nutrients/temps are permissive
Predominant MOs in Soil
Soils can harbor a great variety of MOsYeasts, molds, etc.Soils enriched with raw manure may harbor intestinal pathogensRemoval of soils from foods helps reduce carriage or MOs forward TERM 7
Predominant MOs in Sewage
DEFINITION 7 Can be a source of pathogens if used as nutrients/fertilizer for cropsUsed only if treated (composted) to kill MOs TERM 8
Predominant MOs in water
DEFINITION 8 Water used to irrigate, drinking by animals, for processing, and storing foods can be sources for MO contamination.Even frozen water (ice) for storage is considered a source of contaminationWater as an ingredient (tap water) needs to be assured it is safe from contamination (water quality for foods is also based on mineral content)Water "re-use" is a big issue because of the cost of processing waterChlorine-treated water is used for washing many kinds of foods TERM 9
Predominant MOs in Humans
DEFINITION 9 People are often in contact with foods from farm, to processing, to restaurants and ultimately at homeMajor issues arise during manufacture of ready-to-eat foods and food handlers in restaurantsPersonal sanitation is important as well as those with illness (diarrhea) or infected cuts should be prevented from working with foodsCan have human contribution to spoilage bacteria, but more importantly also Staph, Salmonella, Sigella, E. coli, and hep A TERM 10
Predominant MOs on Food Ingredients
DEFINITION 10 Many fabricated, manufactured, formulated foods contain a multitude of ingredients added in various amounts - these are known sources of spoilage and pathogen contaminationSpices - known to contain molds, spores, and others - can be irradiated to eliminate MOsCan be restricted to below a certain level by Certificate of analysis Letter of assurance Microbial specifications placed with supplier
Commonly used Indicator MOs 3. Fecal
Enterococci
Colonize the intestines of human and warm-blooded animalsSubgroup of them: Used as indicator for presence of virusesMore resistant to heating/drying than the coliform groupRatio FC/FEnt used as indicator for origin of surface water pollution TERM 17
Commonly used Indicator MOs 4.
Enterobacteriaceae
DEFINITION 17 Coliforms & non-coliformsIntestinal & non-intestinalNot all ferment lactoseShould not be present on processed foodsIncludes pathogens TERM 18
Significance of Presence of Coliforms
DEFINITION 18 Coliforms are often expected to be found on raw foods because of their association with the intestinal tracts of animals and their ability to grow in the environment, water, plantsCan be used as a measure of sanitation practices during slaughterA greater significance is their presence on processed foods which is more an indication of post-process contamination TERM 19
What is the significance of coliforms in beach
water? Why?
DEFINITION 19 Great for clams and shellfish
