Food Safety

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Food Safety Processing

• Lecture 13
• March 6, 2008
• Dr. Hirsch

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Exam Results
Average 32.5 (65)
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Why Choose a Farmers Market?

• They help develop a food culture
• Foods are less processed and less packaged
• Foods are usually fresher
• Encourages healthier food choices by promoting
  seasonal fruits and vegetables
• Boosts the local economy

Slow Food Rutgers is hosting its first meeting
on Wednesday, March 12 , 630-730 G.H. Cook
Room of the Cook Campus Center Contact Paul
Valetutti www.slowfood.com
Sunday, March 9th, 1100am to 300pm Winter
Farmers Market Tre Piani Restaurant Forrestal
Village, Plainsboro
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Today Lecture Food SafetyMicroorganisms, Food
Processing

• Defining Food Science
• Food Biology, Microbiology
• Bad and Good Microorganisms
• Pathogens and Outbreaks
• Spoilage
• Probiotics
• Food Safety Safe food storage and preservation
• Food Processing More than just food safety

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Definitions

• Food Science is the discipline in which biology,
  physical sciences, and engineering are used to
  study the nature of foods, the causes of their
  deterioration, and the principles underlying food
  processing
• Food Technology is the application of food
  science to the selection, preservation,
  processing, packaging, distribution, and use of
  safe, nutritious, and wholesome food

http//www.ift.org/cms/?pid1000107
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Food Science
CHEMISTRY

• Composition
• Structure
• Properties
• Chemistry of changes

• Methods and techniques for analysis of
• physical, chemical, nutritive properties

BIOLOGY
ENGINEERING

• Microbiology
• Pathogens
• Fermentation
• Biochemistry
• Nutrition
• Molecular Biology

• Unit operations in
• Processing
• Manufacturing
• Sanitation

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Food Science
Not all Microorganisms are BAD!
BIOLOGY
ENGINEERING

• Microbiology
• Pathogens
• Fermentation

• Unit operations in
• Processing
• Manufacturing
• Sanitation

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Food Safety Foodborne Illness
Illness occurring as a result of ingesting food
or water contaminated with

• Infectious agents
• Bacteria
• Viruses
• Parasites
• A toxin or chemical
• Bacterial toxin
• Pesticides
• Heavy metals
• Other chemical contaminants

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FDAs Rank of Areas of Concern

• Most Dangerous
• Microbial food illness
• Naturally occurring toxins in foods
• Residues in foods
• Environmental contaminants
• Pesticides
• Animal drugs, such as hormones, antibiotics
• Food processing and nutrients in foods
• Least Dangerous
• Intentional Food Additives
• Genetic modification of foods

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Fight Bac www.fightbac.org

• Bacteria are a part of all living things and are
  found on all raw agricultural products
• Harmful bacteria can be transferred from food to
  people, people onto food, or from one food to
  another
• Bacteria can grow rapidly at room temperature
• Growth of harmful bacteria in food can be slowed
  or stopped by refrigerating or freezing
• Food-related illness can produce symptoms from
  mild to very serious. Illness can occur from 30
  minutes to two weeks after eating food containing
  harmful bacteria

Prevention through Knowledge and Action
People who are most likely to become sick from
food-related illness are infants and young
children, senior citizens and people with
weakened immune systems
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Bad and Good of Microorganisms

• Harmful effects
• Food borne disease
• Food infections
• Food poisoning
• Viral borne infections
• Food spoilage

• Beneficial effects
• Fermentation
• Cheese
• Yogurt
• Fermented sausages
• Wine
• Beer
• Pickles
• Sour kraut
• Probiotics

Pathogens
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Harmful Food Infection vs. Food Poisoning

• Food infection
• Live cells delivered by contaminated food
  organism multiply once food is ingested
• Salmonella E. coli
• Food poisoning (intoxication)
• Caused by preformed toxin in the food organism
  may or may not be alive and growing
• Clostridium botulinum Staphylococcus aureus

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Harmful Pathogens of Public Health Concern

• Aeromonas hydrophila
• Bacillus cereus
• Campylobacter jejuni
• Clostridium botulinum
• Clostridium perfringens
• Escherichia coli

• Listeria monocytogenes
• Salmonella
• Shigella
• Staphylococcus aureus
• pathogenic Vibrio spp.
• Yersinia enterocolitica

http//vm.cfsan.fda.gov/comm/ift-over.html
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CDC Estimated Data on Foodborne Disease in the
United States

• 5000 deaths - 325,000 hospitalizations
• 72 bacteria
• 21 parasites
• 7 viruses
• 76 million gastrointestinal illnesses

From W_Fanaselle FDA, CFSAN
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Specific Product Concerns

• Produce
• Imported foods
• Juice
• Eggs

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2006 Nationwide Outbreak of E. coli

• Source Spinach
• Illness in 26 states
• 204 cases of illness reported to the CDC
• 31 cases involving a type of kidney failure
• 104 hospitalizations and 3 deaths
• Four implicated fields on Four ranches
• processing and packaging plant of Natural
  Selection Foods, LLC
• brands include Natural Selection Foods, Pride of
  San Juan, Earthbound Farm, Bellissima, Dole, Rave
  Spinach, Emeril, Sysco, O Organic, Fresh Point,
  River Ranch, Superior, Nature's Basket,
  Compliments, Trader Joe's, Ready Pac, Jansal
  Valley, Cheney Brothers, D'Arrigo Brothers, Green
  Harvest, Mann, Mills Family Farm, Premium Fresh,
  Pro-Mark, Snoboy, The Farmer's Market, Tanimura
  Antle, President's Choice, Cross Valley, and
  Riverside Farms.
• Cause Cattle and pig feces

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Spoilage Microorganisms NOT Harmful

• Food Spoilage Microorganisms
• bacteria yeasts molds
• It is important to be able to distinguish food
  poisoning from food spoilage

Food poisoning is when food is eaten which looks
normal, smells normal and tastes normal you eat
enough to make you ill from the ingested
pathogens or toxins
Spoiled food does not normally cause food
poisoning because it is rejected by the consumer
before ingestion
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Microbial Food Spoilage Changes in Food Quality

• Odor
• due to production of volatile endcompounds
• Color
• pigment production or oxidation
• Texture
• softening due to the breakdown of pectin in
  vegetables or the tissues byproteinases
• Accumulation of gas
• carbon dioxide, sulfur compounds
• Slime formation
• production of dextrans and/or amount of
  microorganisms

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The Good Microorganisms Probiotics

• Human probiotics where?
• Gastro-intestinal
• Skin
• Scalp
• Oral cavity
• Underarm and feet
• Urogenital
• including vaginal

• Expected Benefits with Consumption
• Increased tolerance to infections
• Control of diarrhea
• Reduction of blood pressure
• Cholesterol reduction
• Allergy control
• Immunomodulation
• Cancer reduction

http//www.cook.rutgers.edu/dbm/foodMicrobiologyn
p.pdf
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Probiotics species

• Lactic Acid Bacteria (LAB)
• Lactobacillus
• L. acidophilus
• L. casei
• L. crispatus
• Non-Lactobacillus LAB
• Lactocccus lactis
• Bifidobacteria
• Non Lactic Acid Bacteria
• Propionibacterium
• Saccharomyces cerevisiae

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Prevention of Deleterious MicrobesKnowledge
and ActionFood Handling and Food Processing
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Safe Food Storage and Preparation
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5 Major Risk Factors of Food Safety

• Poor personal hygiene
• Improper holding temperatures
• Inadequate cooking
• i.e. undercooking raw shell eggs
• Contaminated equipment
• Food from unsafe sources

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Fight Bac Educating Consumerswww.fightbac.org
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A day in the life offresh Produce

• Planting and Growing
• Picking
• Handling (cleaning and trimming)
• Blanching inactivates enzymes
• Washing
• Refrigeration or Holding Prior to
• Freezing
• Canning
• Dehydration
• Storage
• Rehandling
• De-frosting
• Rehydration
• Cooking
• Food Service Holding

Washing produce would not have prevented the
E-coli spinach outbreak Cooking fresh spinach
at 160 degrees Fahrenheit for 15 seconds will
kill any E. coli O157H7 present.
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Proper food storage starts at the store

• Shop for shelf-stable items such as canned and
  dry goods first
• Buy refrigerated and frozen foods and hot deli
  items last
• Don't choose meat, fish, poultry or dairy
  products that feel warm to the touch or have a
  damaged or torn package
• Place leaking packages in plastic bags
• Choose only pasteurized dairy products
• Choose only refrigerated eggs
• Check "sell-by" and use by dates on packages
• Buy intact cans that are not bulging, leaking or
  dented on the seam or rim

http//www.fmi.org/consumer/foodkeeper/general.htm
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Cooking
www.foodsafety.gov
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Guidelines for Leftovers
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Food ProcessingMore than Just Food Safety
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Food Processings 3 Goals

• SAFETY
• Microbiologically
• Chemically
• QUALITY
• Flavor
• Color
• Texture
• Nutrition
• FORM (Convenient)
• Ease of use

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Reasons for Processing - Example
MILK

• SAFETY Preservation and Stability
• Decrease microbial load
• Increase shelf life
• QUALITY/FORM Functionality or Form
• More convenient form - conversion
• Better flavor or physical function
• QUALITY Improve Nutrition
• Fortification and Enrichment
• Improved digestibility
• FORM Creation of New, Exciting,
• Fun, Delicious Foods!

Pasteurization
Homogenization
Vitamins AD added
Chocolate Carbonated
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Possibilities from Milk
http//www.foodsci.uoguelph.ca/dairyedu/fluid.html
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Processing ? CookingDesirable effects

• Reduction of microorganisms
• Destruction of toxins
• Inactivation of undesirable enzymes
• Increase in chemical reactions (i.e. browning)
• Improve physical structure for
• Digestibility
• Color
• Texture
• Flavor

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Processing ? CookingUNDesirable effects

• Degradation of
• Sensory attributes
• Flavor
• Texture
• Color
• Nutritive attributes

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Indicators of Nutritional Quality

• Vitamin C
• Thiamine
• Folic acid
• The 3 Nutrients that are most sensitive to heat
  and susceptible to loss during preparation of
  vegetables before freezing and cooking
• Used as the main indicators of the nutritional
  quality of vegetables
• If these nutrients are well retained in food
  after preparation, it can generally be assumed
  that the retention of other nutrients will be as
  high or higher

Via www.nutritionaustralia.org/News_in_Nutrition/
Published_Papers/FrozenVege.pdf Selman, JD.
Vitamin retention during blanching of vegetables.
Food Chemistry, 49 Pp 137 1994. Fennema, O.
Effects of Freeze Preservation on Nutrients. In
Nutritional evaluation of food processing. 3rd
edition. AVI Publishing. Pp 269. 1988.
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Comparison of Greater Stability

• In general
• Minerals MORE STABLE than Vitamins
• Fat soluble vitamins MORE STABLE than Water
  soluble vitamins
• B-vitamins MORE STABLE than Vitamin C

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Frozen sometimes BETTER than Fresh!
Source Strachan, PW. Optimised quality in frozen
foods. IFST Summer Symposium Prospect for
Food September 1982.
http//www.nutritionaustralia.org/News_in_Nutritio
n/Published_Papers/FrozenVege.pdf
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Balancing desirable and undesirable effects Major
Food Attribute Factors
Influencers of the growth of Microorganisms
Processing/storage parameters

• pH
• temperature
• moisture
• oxygen

Increase acidity (? pH)
? processing, ? storage
Decrease amount of water
Create Barrier - packaging
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Important Processing Operations

• Heat transfer
• cooling
• refrigeration
• freezing
• Mass transfer (may or may not require a change in
  state)
• Distillation
• Crystallization
• Membrane processes
• Drying
• Evaporation
• Mixing
• Homogeneous Blends
• Liquids or dry

Killing and Preserving
Altering Condition like water availability
Adjusting pH Adding preservatives
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Milk Processing-Pasteurization
http//www2.automation.siemens.com/dairy/html_76/p
rocess/dairy_02.htm
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Potato Chip Manufacture
http//www.tsunghsing.com.tw/pro-1-3.htm