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This 9 page Class Notes was uploaded by Alyssa Leathers on Saturday December 6, 2014. The Class Notes belongs to 2210 at Ohio State University taught by a professor in Fall. Since its upload, it has received 91 views. For similar materials see Human Nutrition in Natural Sciences at Ohio State University.
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Date Created: 12/06/14
0 Multiply and sporulate in gut produce toxin that causes the symptoms Prevention 0 Proper cooking and cooling 0 Take care with large roasts and large gravy bowls can take long time to cool 0 Cooking cooled products before consumption will kill organisms Clostridium Botulinum Responsible for majority of food poisoning deaths Of outbreaks small Home canned food products canning no oxygen available Common soil organisms very hard to eliminate from foods vegetables Spore formers that are heat stable outbreaks most likely occur in improperly processed foods need lots of very intense heat to prevent Characteristics 0 Primary soil source 0 Anaerobic spore former o Isn t produced if pH is below 46 o Spores are very heat stable toxin can be destroyed by heat Symptoms 0 Double vision dizzy nausea vomiting respiratory failure 0 2436 hours after ingestion 0 Die within a week 0 Antioxidant administration save life Cause 0 Toxin produced above pH level of 46 o Canned food improper heat processing Staphylococcus Aureus Sources sores boils infected skin areas nasal passages of man and animals Symptoms fever is not present similar to all other food illnesses o 24 hrs 0 16 hrs After consumption Food Preservation prolong shelf life reduceeliminate pathogenic organisms maintain food quality Blanching mild heat treatment fruits and vegetables used to inactivate enzymes decrease product quality 0 Destroy surface microorganisms extend shelf life 0 Primary objective enzyme inactivation Pasteurization low energy thermal process 0 1 Designed to destroy all pathogenic harmful microorganisms present in a food that might grow in specific products 0 2 Extension of shelf life by decreasing the number of spoilage organisms present 0 Product isn39t sterile and will be subject to spoilage Ex milk heat 161F for 15min or 145F for 30min 0 Cold pasteurization liquids only Sterilization complete destruction of all microorganisms o 25OF for 15 min higher temperatures destroying all spores Organisms clostridium botulinum is the most heat resistant of all pathogens most deadly If organism is destroyed the pathogens will also be killed target most heat resistant to conquer all others Time temperature 0 Many combinations of heating times and temperature to give same lethality for C botulium o How long do we need to heat a food to ensure it39s safe Heating at 250F at 15 second each Decimal reduction 12D reduction Low Acid Foods 0 Need to use 12D reduction process 0 Exact number of spores in a food unknown 0 Adequate safety margin Drying Microorganisms can39t grow if moisture is too low Drying to the point where growth can39t occur Must be economical and not damaging Sun drying grains fruits coconut 0 OOO Called ionizing radiation Amount of damage is related to the amount of water Uses inactivate enzymes kill bacterial cellsspores kill insects Amount of energy to kill insects much lower than that requires to kill bacterial spores Same ions that kill cells can cause breakdown of food molecules Safety Irradiated foods are as nutritious as food processed conventional methods Foods that don39t contain radioactivity Unique Radiolytic Products URPs Long history with medical devices Approved Uses List Radura irridation is a process but it must be labeled like an additive food must contain the symbol Likely Applications Removal of insects from grainsfruits Decrease mold content of fruits Pasteurization of meat products Problems Consumer acceptance Plants NIMBY not in my backyard Product High cost to sterilize Anti nuclear lobby