Title: A SAFE FOOD SUPPLY?
1A SAFE FOOD SUPPLY?
- Is Your Food Safe to Eat?
- Mr. Johnson
- Central Heights Ag Dept.
2Student 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.
3Student 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.
4Food 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.
5Does 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.
6Rumors 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.
7Pesticides 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.
8APPLES 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
9The 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.
10Chemicals
- 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.
11So 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.
12Allowable 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.
13To 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
14MEAT 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.
15Meat 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.
16Meat 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.
17Meat 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.
18Meat 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.
19Hormones 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.
20Hormones 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.
21Hormones 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.
22Hormones 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.
23Hormones 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.
24Preservatives
- 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.
25Preservatives 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.
26Fat 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.
27Fat 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.
28Fat 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.
29Labeling 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.
30Nutritional 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.
31Summary
- 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.
32The Science of Food Preservation
33Causes 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 .
34Causes 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.
35Chemical 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.
36Chemical 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.
37Food 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
38Food 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.
39Food 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.
40Food 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.
41Food 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.