A SAFE FOOD SUPPLY?

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A SAFE FOOD SUPPLY?

• Is Your Food Safe to Eat?
• Mr. Johnson
• Central Heights Ag Dept.

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Student Objectives

• Analyze the risk involved in the use of
  pesticides in food production.
• Evaluate the risk of using hormones and
  antibiotics on animals raised for food.
• Explain the safeguards to prevent harmful
  pesticides residues on food.
• Describe the use the body makes of cholesterol.

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Student Objectives

• Describe the safeguards used in the meatpacking
  industry.
• Discuss the use of chemical preservatives in
  food.
• Distinguish the difference between saturated and
  unsaturated fats.

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Food SAFETY????

• Americans enjoy an abundant, diverse, and
  relatively inexpensive food supply.
• Most people are not involved with the production
  and processing of the food they eat.

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Does the media make the food unhealthily?

• In the past few years the media has reported that
  foods or components of the food that we eat are
  either unhealthy or hazardous to our health.

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Rumors Spread FAST!!!

• It is easy to forget that properly conducted and
  reported scientific research is responsible for
  the abundant, safe supply of food we enjoy.
• Inconclusive or poorly reported research can
  often mislead the public.
• Poorly reported research can cause prices to drop
  within minutes.

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Pesticides and Chemicals

• In 1989, the Natural resources defense Council
  published a report entitled Intolerable Risk
  Pesticides in our Children's Food.
• The report stated that a chemical called Alar
  that was used to prevent apples from falling from
  the tree to early. Which allows the fruit to have
  a better shape and color.

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APPLES KILL CHILDREN!!!

• According to reports when the chemical was feed
  to lab rats it was proven to be carcinogenic.
• This caused panic!
• Apples were dumped
• Banned from schools

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The Damage was DONE.

• Apples were removed from sale.
• The apple industry suffered a tremendous result
  more than a 100 million Dollars!!
• It was poorly presented information- In fact a
  person would have to eat 28,000lb of apples a day
  for 10 yr.. to equal the amt.. of Alar that
  caused the tumors in the lab rats.

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Chemicals

• Even though the chemical Alar was considered safe
  in low amounts it was still pulled off the
  market.
• A chemical must pass over a 120 separate test
  before it can be released for use.
• On Average only one in 20,000 chemicals are
  approved for use ag producers.

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So are pesticides harmful to humans?

• Pesticides kill insects, weeds, and plant
  disease organisms.
• Modern insecticides, fungicides, and herbicides
  have a low level of toxicity to humans.
• Even at full strength it would take a a lot to be
  lethal.

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Allowable levels?

• Allowable levels are measured in parts per
  billion or parts per trillion.
• Almost all substances can be toxic or hazardous
  at some level.
• Salt is a necessary component of our diets but if
  some one ate enough salt they would die from a
  salt overdose.

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To be organic or not to be?

• A recent trend is to eat organically grown
  food.(Food that is grown without pesticides or
  herbicides.)
• Some people feel that this is safer food but
  research shows no advantage. In fact there are
  more disadvantages.
• Natural toxins, Cost, Damage caused by insects
  can harbor bacteria which can be more harmful
  than the pesticides

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MEAT INSPECTION

• All meat sold to the public must be inspected.
• Quality grading refers to the quality of the
  meat- determined by Age and intermuscular fat.

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Meat inspection cont.

• Yield grading refers to the amount of lean retail
  cuts the carcass will yield.
• Meat inspection guarantees that the meat will be
  safe, wholesome, and accurately labeled.

• Meat inspection includes several phases.
• Live inspection-ante-mortem.
• Internal organs are inspected.

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Meat inspection cont.

• When carcasses and/or part fail inspection, they
  are condemned.
• Condemned carcasses go through a process called
  rendering.

• Rendering is where the condemned are placed under
  enough heat to kill any organism that could cause
  problems.

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Meat inspection cont.

• Rendered meat is used for by-products other than
  for human consumption.
• Each slaughter house is inspected for cleanliness
  and free of bacteria, ect...

• In the processing line, all carcasses must be
  thoroughly cleaned to remove debris from the
  slaughter process blood, loose tissue particles,
  or foreign particles.

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Meat inspection cont.

• If meat becomes contaminated by fecal matter,
  ect.., that portion of the carcass are trimmed.
• With best measures, meat will still contain
  bacteria and other microbes.

• For that reason it is important that meat is
  thoroughly cooked before consumption.
• Almost all of the sickness caused from eating
  meat can be attributed to improper cooking
  procedures.

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Hormones and Antibiotic Residues

• An area of consumer concern is the use of
  synthentic growth and reproductive hormones in
  beef and dairy animals.
• The concern is that this will cause harmful
  effects in humans.

• Growth hormones redirects energy from the
  production of fat to the production of lean.
• More weight is gained at lower cost and is more
  efficient and healthier.

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Hormones and Antibiotics cont.

• Livestock and poultry industries use antibiotics
  to cure or prevent diseases.
• The concern is that pathogens can build up an
  immunity to the drugs, as a result of residue of
  the drugs in the meat.

• The hormone is placed under the skin in the
  animals ear and are slowly released as the
  animal grows.
• The ear is removes at slaughter to prevent
  residue from accumulating in the edible meat.

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Hormones and Antibiotics cont.

• According to the National Academy of Science, no
  data has been found that implicates the use of
  antibiotics in animals used for food as a health
  risk to humans.

• Another concern for humans in the dairy industry
  is using bovine somatotropin, (BST).
• This natural hormone stimulates cows to produce
  more milk.

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Hormones and Antibiotics cont.

• The concern is that the use of BST is a health
  risk, but there is no evidence to support that.
• In fact, milk from cows treated with BST is
  almost identical as cows with out BST.

• BST is a protein and can be digested and is not
  passed into the systems of humans.
• The FDA closely monitors meat, dairy products and
  all food from animals for residues of pesticides,
  drugs, and hormones.

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Hormones and Antibiotics cont.

• If levels are detected that go beyond safe
  tolerances, that product is condemned at the
  producers expense.
• This gives producers incentives to adhere to the
  guidelines and withdrawal periods.

• A withdrawal period is the time between when the
  substance was administered to the animal until
  the animal can be slaughtered or the milk used.

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Preservatives

• Many people are concerned over adding
  preservatives such as nitrates, citric acid,
  sodium benzonate, and phosphoric acid to foods.

• The purpose of these additives is to prevent the
  formation of toxic substances associated with the
  spoilage of food.
• These foods are susceptible to the growth of
  bacteria that can cause food poisoning.

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Preservatives cont.

• The likelihood of any health problems arising
  from chemical preservatives added to foods is
  insignificant compared to the food poisoning that
  can occur in untreated food.

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Fat Content in Food

• Studies have shown a relationship between diets
  high in fat and health problems (obesity, heart
  disease, cancer, etc.)
• Concern has been expressed over eating red meat
  because of the high amount of fat and also
  because of the cholesterol content.

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Fat Content in Food cont.

• Both fat and cholesterol are necessary components
  of human diets, but excessive amounts of either
  can cause problems.

• Fats are divided into two broad classifications
  saturated fat and unsaturated fat.
• Unsaturated fats are in a liquid state at room
  temp.
• Saturated fats are in a solid state at room temp.

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Fat Content in Food cont.

• Eating red meats from animals such as cattle and
  sheep is safe as long as the amounts are moderate
  and are part of a balanced diet.

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Labeling of Foods

• President Roosevelt passed the Federal Food and
  Drug Act and the Federal Meat Inspection Act.
  These laws were the first steps in the regulation
  of the food industry as to the safety and quality
  of foods.
• Laws regarding the processing and labeling of
  foods have continually been upgraded and improved
  since that time.

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Nutritional Labeling

• About 90 of all processed foods must have
  nutritional labeling on the package.
• Exceptions-
• Coffee
• Tea
• Flavorings that contain no significant amounts of
  nutrients

• The nutritive content of the food is expressed in
  terms of Daily Value (DV)
• The DV refers to the percent of the nutrient in
  the food that is recommended based on a 2,000
  calorie diet.

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Summary

• Foods are safer now than at any time in history.
• Improper cooking, spoilage, and mishandling of
  the foods by the consumer are by far the biggest
  causes of food safety problems.

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The Science of Food Preservation
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Causes of Food Spoilage (But What About
Bacteria?!)

• Microbes - extremely small organisms.
• Louis Pasteur discovered the presence of microbes
  and brought about the process known as
  pasteurization (this renders the microbes in milk
  harmless)

• Bacteria- microbes that are responsible for much
  of the decay and spoilage of the plant and animal
  tissue in foods.
• Bacteria makes the food not fit to eat because of
  the smell and taste and can often be dangerous .

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Causes of Food Spoilage cont.

• Molds- microbes that also aid in the breakdown of
  plant and animal tissues.
• Toxins from molds are called mycotoxins and may
  cause illness when consumed.
• Molds appear as fine, hairy fillaments on the
  surfaces.

• Yeasts- single-celled fungi.
• Used extensively in the fermentation of
  carbohydrates.
• Many yeasts are beneficial, but they may also
  cause food spoilage by growing on the food.

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Chemical Causes of Food Spoilage

• Enzymes can cause sugars to turn into fats or may
  cause proteins or fats to change in makeup or
  function.
• Up to a point, certain enzymatic changes are
  desirable in that they trigger the creation of
  sugars in the ripening process.

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Chemical Causes cont.

• Rancidity is a chemical process that takes place
  in fats that causes food spoilage.
• Hydrolytic rancidity comes about as a result of
  reactions of the fatty acids with water
  molecules.

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Food Preservation in Fresh Foods

• After fruit has been picked, washed, and cleaned,
  they are coated with a thin layer of paraffin to
  prevent damage to the skin.

• In a process called controlled-atmosphere
  storage, the respiration of the fruit cells is
  controlled. They are placed in dark chambers with
  controlled temps.
• This keeps some fruit fresh for many months

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Food Preservation by Drying

• The first method of preserving food was drying.
• If the water is removed from food, the microbes
  and enzymes are unable to live and reproduce.
• The most modern technique of drying is
  freeze-drying.In this process, the product is
  quickly frozen and placed in a chamber where a
  vacuum is drawn. This allows the water molecules
  to go almost directly from ice to vapor.

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Food Preservation by Salting

• By covering meat with salts, the water in
  microbes passes to the salt and the microbes dry
  out and die.
• Sugar can also be used as a preservative because
  the same principal applies.

• The problem with salting is removing the salt
  from the food being preserved.
• Therefore, the only foods preserved in salt today
  are those such as fat back and salt pork.

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Food Preservation by Fermentation and Pickling

• Solutions high in salt and vinegar give the
  advantages of the salt solution dehydrating the
  microbes and the vinegar lowering the pH to a
  level intolerable to the microbes.

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Food Preservation by Freezing

• Early iceboxes that were used, cooled food with a
  large block of ice stored in the compartment with
  the food.
• Microbes cannot live well in cool temperatures,
  so the food can be preserved longer.