Human Nutrition 210 Final

Front 1

Radura

Back 1

Irradiation is a process, but it must be labeled
like an additive. Food must contain this symbol.

Front 2

Sterilization

Back 2

• Refers to the complete destruction of microorganisms.
• Often requires at least 121 °C (250F) for 15 minutes to
destroy all spores.
• In practice, food would require much longer times
because there is a lag between exposure to heat and
when the product reaches the desired temperature.

Front 3

E. Coli O157:H7 - General

Back 3

One of the hundreds of strains normally found in the large intestine of animals. Most commonly linked to
undercooked ground beef, but outbreaks have been
traced to sprouts and unpasteurized fruit juice.

Front 4

E. Coli O157:H7 - Symptoms

Back 4

• Severe abdominal pain, cramps, nausea, vomiting, bloody diarrhea and occasionally fever.
• Hemolytic Uremic Syndrome (HUS) is a serious
consequence of this disease and is the leading
cause of kidney failure in children.
• Central nervous system disease, seizures, coma
and blood clots in the brain may also develop, and
may result in death.

Front 5

E. Coli O157:H7 - Causes

Back 5

• The organism resides in the intestinal tract and is shed
in the feces.
• Slaughter and milking procedures can contaminate
food products.
• Bacteria usually are only found on the exterior of
intact products, and can be easily killed during the
cooking process. Hamburger and other ground meat
products may evenly distribute the bacteria
throughout the product.

Front 6

E. Coli O157:H7 - Prevention

Back 6

• Food-protection education
• Cook meats thoroughly, until the juices run
clear. (155ºF for ground meats/hamburger)
• Avoid cross-contamination (contact of raw
food with cooked foods)
• Good personal hygiene with an emphasis on
hand washing

Front 7

Fat digestion - General

Back 7

• ~95% consumed is absorbed
• Triglyceride from food becomes triglyceride in adipose
• Problems:
1.Triglycerides are large
• Primary enzyme for digestion - Pancreatic Lipase
2. Water and fat do not
mix

Front 8

Fat digestion - Stomach

Back 8

• Gastric lipase works only in an acidic environment.
• Gastric lipase acts on triglycerides containing short & medium chain fatty acid.
• Longer fatty acid chain is not affected by the stomach.

Front 9

Fat digestion - Small Intestine

Back 9

•
Primary site of fat digestion
•
CCK stimulates pancreas to release pancreatic lipase

• Pancreas release lipase

• Bile acid emulsifies digested fat

• Fat is broken down to monoglycerides and fatty acids

Front 10

Pathogenic Growth

Back 10

• Invade the host (in this case man) and create problems.
• There are no pathogenic organisms that can grow
at a pH below 4.6.
• Temperatures between 40 and 140 support growth.
• Contamination causes growth very rapidly.

Front 11

Prokaryotic Cells

Back 11

• No nucleus.
• Has a cell wall.
Reproduction:
• Bacteria reproduce by binary fission, resulting in two
genetically identical daughter cells.
• Mechanism is simpler than for eukaryotic cells.
• Simplicity gives potential for very rapid population
growth.

Front 12

Microorganism Growth

Back 12

Factors that affect the growth of bacteria:
• Nutrients
• pH
• Oxygen tension
• Temperature
• Water activity
• Presence of other microorganisms.

Facts:
• Reproduce by binary fission in a geometric manner
• Under ideal conditions can double in 20 minutes.
100 organisms can become 1 million in 3.5 hours.
• In may cases between 100,000 and 1 million
organisms per gram will cause an effect.
• In some special cases this number may be as low as
10 viable organisms.

Front 13

Soluble Fiber

Back 13

• Pectin
• Lower cholesterol, regulate blood sugar (diabetes)
• Fruit, vegetable, rice bran, psyllium husk, flax seed

Front 14

Vitamin D

Back 14

• Sunshine exposure
• Maintain blood calcium/phosphorous
• 1. Bone – Mobilize calcium
• 2. Intestine - Increase calcium and phosphorous absorption
• 3. Kidney -Reabsorb calcium and phosphorous
• Maintain bone integrity

Front 15

Niacin

Back 15

• B3
• Lowers cholesterol.
• Formed from amino acid tryptophan.
• Flushing - "____ Rush"
• Releases energy from carbohydrate, protein, fat
• Component of two coenzymes involved in
oxidation/reduction reactions
• NAD and NADP
• Make proteins, DNA, RNA
• Meat, liver, peanut butter (corn is a poor source)
• Deficiency - Pellagra and 4D's

Front 16

Listeria

Back 16

• Can grow in the cold (psychrophile).
• Ready to eat foods.
• Pregnant women - can cause spontaneous abortion.
• Commonly found in feces and milk of humans and
animals.

Front 17

Folate

Back 17

Function
• Regeneration of cells
• Synthesis of DNA
• Red blood cell formation

Deficiency
• Megaloblastic anemia (large immature red cells).
• Neural tube defects (NTDs, spina bifida).
• From maternal folate deficiency & genetic defect in folate metabolism.

Front 18

Vitamin B12

Back 18

• Similar to folate
- Growth
- RBC formation
• Unique function
- Maintains nerve insulation: myelin sheath

Front 19

Aerobic glycolysis

Back 19

• Microorganisms require oxygen to grow.
• Plenty of oxygen available.
• Low to moderate intensity.
• 30-32 ATP/glucose
• ATP replenished slowly.
• Sustained ATP production (2 min. - 3 hrs. of work).

Front 20

Anaerobic Glycolysis

Back 20

• Limited oxygen (increased physical activity).
• Pyruvate converted to lactate.
- Produces 2 ATP/glucose
• Replenishes ATP quickly
- Cannot sustain ATP production
- 30 sec. - 2 min. of work.
• Lactate buildup
- changes in acidity that inhibits glycolysis enzymes

Front 21

Protein Intake

Back 21

Most people obtain enough protein through their normal, daily diets.

Front 22

12 D Process

Back 22

Heating canned foods long enough and at a high enough temperature that the number of spores would decrease by a factor of 10^-12.

Front 23

Colstridium perfingens

Back 23

• Cooked meat products and gravies are the primary foods
involved in these outbreaks.
• Is an anaerobic spore farmer
and thus doesn't present a hazard in raw foods. Live organisms must be ingested before illness occurs.
• Foods are cooked enough to kill competing
organisms, but not enough to kill perfringens spores.
• Foods are then allowed to cool slowly by being left
out at room temperature or by being improperly
refrigerated.
• Organisms multiply and then are consumed and
sporulate in the gut.
• When they do this, they produce a toxin that causes
the symptoms.

Front 24

Triglycerides/fat

Back 24

• 95% if lipids in foods and bodies.
• Primary enzyme for digestion - pancreatic lipase.

Front 25

Glucose; monosaccharides

Back 25

• One of carbohydrates simple sugars; major sugar in body.
• Major energy source.
• Maintenance of glucose levels in plasma (brain).
• Part of its molecule comes from the sun's energy.

Front 26

Limiting Amino Acid

Back 26

• Specific amino acid present in the lowest quantity compared to need.
• When necessary amino acids are present, protein synthesis occurs.
• If even one necessary amino acid is missing, protein synthesis stops.

Front 27

NIMBY

Back 27

• "Not In My Back Yard"
• Deals with consumer acceptance of new developments being built near their homes.

Front 28

Goiter

Back 28

• Iodide deficiency.
• Thyroid gland enlarges with low
intake of iodide.

Front 29

Pasteurization

Back 29

• A comparatively low energy thermal process with two
main objectives:
– Designed to destroy all pathogenic microorganisms
that might grow in a specific product.
– Extension off shelf life by decreasing number of
spoilage organisms present.
• Product is not sterile and will be subject to spoilage.
• Mild heat treatment designed to kill organisms that:
– Cause disease (pathogens)
– Cause major spoilage

Front 30

Vitamin A Deficiency

Back 30

• Cells stop secreting mucus
become dry, hard, and die.
• Night blindness
• Stunting of growth
• Xeropthalmia
• Problems with skin and epithelial cells that line
respiratory, digestive and genitourinary tracts.
• Abnormalities of enamel-forming cells of the teeth.
• "Golden Rice"

Front 31

Polyunsaturated/ Monounsaturated fats

Back 31

• One or more double bonds.

• Most plant oils.
• Mono: One double bond.
• Poly: Two or more double bonds.
• Olive oils.

Front 32

Bacillus cereus

Back 32

• Implicated in a number of food poisoning outbreaks. A notable one occurred here in Columbus.
• Common spore former. Because the spores are relatively heat stable, some will survive cooking.
• Often associated with RICE being held at improper temperature.

Front 33

BMR

Back 33

• Basal Metabolic Rate
• Energy required to sustain life.
- At rest but awake.
- Varies by individuals.
- Heartbeat, respiration, body temperature.
• 60-70% of total energy needs.

Front 34

Iron Stores

Back 34

• "Body's Gold"
• Deficiency - Anemia.
• Upper small intestine is absorption site.
• Low storage - increased absorption.

Front 35

Vitamin A

Back 35

• Most important vitamin.
• Xerophthalmia - pathologic dryness of the conjunctiva and cornea.
• Functions
- Vision—night blindness and ultimate blindness.
- Maintains body linings and skin.
- Bone growth.
- Reproduction.
• Active form - Retinol.
• Precursor - Carotene.

Front 36

Pathogenic Bacteria

Back 36

Any type of bacteria that has the ability to cause infectious disease.