Food

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Food Beverages
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• I. All foods have Microorganisms on their
  surface.
• II. Microorganisms take food for metabolism and
  turns it into acids, alcohols, gas.
• III. Sometimes desirable pleasant tastes
  textures.
• IV. foods altered by the careful
  controlled growth of microorganisms
• A. sour cream blue cheese.
• B. Spoilage, sour milk, molded bread does
  not change the quality of food but may lead to
  illness

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• V. Factors Influencing the growth of organisms on
  foods
• A. (aW)
• 1. Bacteria - .9 or higher for growth
• 2. Fungi lower aW
• B.
• Most are inhibited by acidic conditions.
• C.
• Low temperatures slow down enzymatic
  activities.
• D.
• 1. Nutrients
• 2. Coverings
• 3. Antimicrobials

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• VI. Production of foods beverages
• A. BC Sumerians Babylonians
• B. BC Egyptians bread beer
• C. Milk
• 1. from cow but leads to contamination.
• 2. Lactic Acid
• 3. Yogurts
• a to eliminate undesirable spoilage.
• b. Inoculated with Streptococcus thermophiles
  or Lactobacillus bulgaricus.
• c. Incubated at 40C.
• d. Produces lactic acid, pH drops causing
  of milk protein which changes texture.
• e. Conditions are controlled so only certain
  bacteria can grow.
• f. ½ million pounds of yogurt is sold in US,
  yearly

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• 4. Cheese
• a. yrs ago Asia
• b. Steps
• 1. Milk inoculated with starter culture
  (Lactic Acid bacteria).
• 2. Incubated until fermentation of milk
  sugars
• 3. (enzyme) is added to milk proteins
  (CURD).
• 4. (CURD) is separated from liquid
  (WHEY).
• 5. cottage cheese, - Cheese

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• c. Types of cheeses
• 1. White fungus, Pencillium caseisolon
• 2. Bacteria, Brevibacterium linen
• 3. Bacteria, Propionibacterium sp.
• a. Produces propionic acid CO2.
• 4. Cheeses content
• a. very hard, semi, soft

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• D. Pickled Vegetables Olives
• 1. Made with bacteria
• E. Sauerkraut
• 1. Cabbage is shredded layered with .
• 2. Salt out cabbage to prevent bacteria
  growth.
• 3. Permits bacterial growth (Lactobacillus
  plantarian) in 2- 4 weeks.
• 4. pH levels results in tangy taste

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• F. Soy Sauce
• 1. soy bean Aspergillus oryzae.
• 2. Mix salt, soy bean, wheat
• 3. Let sit for 3 days
• 4. Carbohydrates are broken down to produce
  fermentable sugars.
• 5. Mixed with 18 bacterium
  (Pediococcous soyae saccharomyces rouxi) for
  8 12 months.
• 6. Liquid is drained for soy sauce

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• G. Breads Bakers Yeast
• 1. Leavened Bread.
• 2. Mixture of flour, sugar, milk, water,
  yeasts (Saccharomyces cerevisiae), butter or
  oil.
• 3. ferments carbohydrates from sugar to
  .
• 4. Produces ethanol gas which is in baking.
• 5. CO2 causes bread to .

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• H. Alcohols
• 1. From fruits.
• 2. 10 million yeast cells on grapes.
• 3. Fruit sits for days at room temperature and
  begins to bubble as juices ferment.
• 4. Weeks mixture alcohol

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• 5. Wine
• a. Crush selected grapes solids juices
  .
• b. Red wine
• 1. Red grapes
• 2. Entire grape
• c. Only juice from red grapes
• d. red for a day then only juices
  ferments.
• e. S. cerevisicae for growth.
• f. , controlled temperature for days to
  weeks.
• g. Sugar
• Ethyl alcohol CO2.
• Less than 14 alcohol

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• 6. Beer
• a. Fermentation of sugars from grain by
  Saccharamyces.
• b. starch to sugars
• 1. (germinating grain) is soaked in water
  to yield an extracting enzyme (wort) sugars
  nutrients for yeast growth.
• c. is boiled to destroy enzyme most
  microorganisms.
• d. are added for flavor inhibited unwanted
  bacterial growth.
• e. Brewers Yeast alcohol.
• f. Sits in vats to settle out solids including
  yeast microorganims flavoring.
• g. S carlsbergensis 6 12 C 8-14 days
  (American beer).
• h. S cereviside 14-23 C 5 7 days,
  carried to top by CO2. Stouts.

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• 7. Distilled Spirits
• a. Similar to beer except boiled.
• b. continues during fermentation.
• c. Alcohol is separated by .
• d. sugar cane or molasses.
• e. barley aged in oak or cherry barrels.
• 8. Vinegar
• a. Product of oxidation of ethyl alcohol by
  acetic acid bacteria.
• b. 4 acetic acid.

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• VI. Food Spoilage
• A. Growth of on or in food that produces an
  undesirable change.
• B. of food determines the type of
  microorganism .
• C. Bacteria commonly involved in food spoilage
• 1. Gram Negative
• a. . Wide range of food temp.
• b. . Degrade fruits vegetables.
• c. . ethyl alcohol to acetic acid
• d. . degrade cottage cheese

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• 2. Gram positive
• a. Streptococcus, Leuconstoc Lactobacillus
  
• b. Bacillus Clostridium .
• c. B. coagulans Strearothermophils sour
  spoilage of some .
• D. Fungus
• 1. Rhizopus sp.
• 2. Aspergillus

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• VII. Food Borne illness
• A.
• 1. Hours
• 2. Consumption of a toxin produced by a
  microorganism growing on a food product.
• ex. Staphylococcus aureus ham, pasteries,
  salads
• nausea vomiting.
• B.
• 1. Neurotoxin by Clostidium botulinea (Gram
  positive)
• 2. Errors in canning with endospore
  contamination.
• ex canned food bulging
• C. - Salmonella E. Coli
• 1. Infection after ingestion in the small
  intestines by a living organisms.
• 2. Up to 24 hrs to feel effects resulting in
  diherrhea
• 3. Prevention
• a. Thoroughly cook food.
• b. Wash cutting board to prevent cross
  contamination.

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• IX. Food Preservation
• A. Drying
• B. High Temperatures
• C. Low Temperatures
• D. Irradaition
• E. Sugar
• F. Smoked
• G. Pasteurization
• 1. High temp
• 2. Low temp
• 3. Ultra high