Presentation on theme: "Hygienic and Safe Food Processing Workshop CTC Center Lundazi May 2007 Dr. Carmen I. Moraru and Elisabeth A. Bihn Cornell University."— Presentation transcript:
Hygienic and Safe Food Processing Workshop CTC Center Lundazi May 2007 Dr. Carmen I. Moraru and Elisabeth A. Bihn Cornell University
Can foods harm people? When? If they are not properly: –Processed –Stored –Handled –Prepared/consumed Yes, sometimes foods can make people very sick!
Where does this happen? Everywhere in the world, including Africa and the United States of America! –Example: in the US alone, millions of people suffer every year from food poisoning Symptoms: headaches, stomach aches, nausea, vomiting, diarrhea, etc. Sometimes people can even die! Can you think of a situation when you felt sick because of the food you ate?
What is the cause? Extremely small living organisms, called BACTERIA How small are bacteria? –About one million times smaller than a human –Cannot see them with the naked eye, only with a microscope How do they look like under the microscope? –Some are round- Others are like a rod
Hepatitis A virus Norwalk-like virus Additional harmful organisms of concern in foods Viruses Cyclospora Cryptosporidium Giardia Parasites Viruses
Food contaminated with bacteria Bacteria survive and even grow in foods, especially under warm conditions Consumers may gets sick after eating the contaminated food Are all food related bacteria dangerous? Some bacteria are useful –E.g. used to make certain foods such as yogurt, cheese Others can be harmful: –Spoil the food: spoilage bacteria –Make people sick: pathogenic bacteria
Salmonella species –Sources: eggs, poultry, peanuts (it gets transmitted into peanut butter, too!) E. coli O157:H7 –Fruits and vegetables, untreated water Shigella species –Fruits and vegetables, products of animal origin Bacillus cereus –Fruits and vegetables (transmitted through soil) Listeria monocytogenes –Fruits and vegetables, milk, meat (beef) Vibrio cholera –Fruits and vegetables, seafood. Transmitted through water. Staphylococcus aureus –Mostly from humans (skin infections, nose, etc.). Examples of harmful bacteria that can be transmitted through foods
Important information about bacteria Under optimum conditions (moisture, food, warm temperatures) bacteria double in number every 30 minutes… Ex: 1 becomes 2, 2 become 4, 4 become 8, and so on... How long will it take one bacterium to multiply to 100 cells? *** 3.5 hours ***
How many bacteria are needed to make us sick? (Hemolytic Uremic Syndrome)
How do bacteria get into foods? Agricultural raw materials Water Air / dust Soil Food handlers/ people Packaging materials Animals and birds Garbage and sewage Rodents Insects
Contamination sources for local foods 1. Soil
2. Domestic animals and birds From skin, feathers, manure, bedding materials, sheds, etc. Contamination transmitted mostly by people who touch animals or birds and do not wash their hands before touching foods
… and even from wild animals! Less likely Mostly through manure
3. People How can people contribute to microbial contamination of foods? During processing and handling During packing In distribution and food service facilities At home! Main vehicle?
What can we do to fight bacterial contamination? Proper agricultural practices –Critical particularly for the safety of fresh fruits and vegetables –Proper fertilization, drainage, etc. –Proper harvesting and handling –Proper personal worker hygiene Proper processing –Hygienic processing facilities –Proper processing methods –Clean, sanitary equipment and utensils –… and again, proper personal worker hygiene! Food Safety: Farm to Fork!
At the farm This is where food quality and safety start … or get compromised!
Proper personal worker hygiene Very high standards of personal hygiene for food handlers are required Sources of contamination from workers: –Injuries – cover them up! –Illness, such as food poisoning, food-borne diseases, or other existing infections – don’t come to work when sick! –Personal habits: chewing, spitting, scratching the nose, smoking. None of these should be done in the room where food is handled! –Personal clothing
Food processing worker apparel Clean Used only in the food processing facility Consists of: –Lab coat –Hair cover (hat or hairnet) –Beard / mustache net to cover facial hair (when applicable) –Clean shoes or shoe covers. For sensitive products (e.g. peanut butter), workers should not walk outside with the same shoes! –Gloves when necessary
Remember the main vehicle of food contamination by people? What can workers do to prevent this? Wash their hands!
When should you wash your hands? ALWAYS AFTER: Using the toilet Handling food Touching animals Eating, drinking or smoking
Proper hand washing Water and soap physically remove particles of soil and microbes from skin Rubbing and scrubbing are important
Also very important! Always use clean water Never wash your hands in used wash water
What else needs special attention? Cracks, calluses, fingernails, and rings can shelter dirt and pathogenic microbes (“germs”) Use a nail brush to remove all dirt from underneath the fingernails
Proper Handwashing Reduces infection 35 to 50% Reduces gastro intestinal illness by up to 80% What is effective hand washing?
Practical exercise Let us wash our hands!
Hand washing demonstration Four groups –Rinse only –Five-second wash –Ten second wash –Twenty-second wash Use Germ Glow test kit to check for cleanliness
Proper handwashing reduces risks PREVENTION is the key to reducing microbial contamination of foods!
Prevention of bacterial contamination and growth in foods during processing Important facts about processing: Cook and maintain foods at the correct temperature –High temperatures kill bacteria –Low temperatures (refrigeration) stop their growth Besides cooking, other methods can also help preserve foods: –Salting –Smoking –Drying –Adding sugar Correct handling, preparation, cooling and processing of food are extremely important Rotate stocks of raw materials and finished foods can prevent food poisoning and spoilage. Rule: FIRST IN – FIRST OUT!
Premises and equipment Maintain premises clean: no dust or dirt on floors, walls, processing surfaces, processing equipment Do not accumulate waste or used water in the processing facility. Dispose them hygienically. Authorized personnel permitted only Clean shoes or use shoe covers when entering premises Always wash hands when entering the food processing facility
Pest control Food pests: – rodents – birds – insects; Keep all pests out of processing and storage spaces, because they are an important source of contamination Acceptable methods of controlling pests in food premises: –Prevent entry (nets, keep doors closed, etc.) – BEST method! –Do not leave food waste or uncovered food laying around –Could use traps for rodents –Do not use poison!
Good Manufacturing Practices (GMP) during food processing Separate different products, particularly raw materials from final products. Chill. As much as possible, keep foods in cool and dry spaces, as cold storage is one of the most effective ways to reduce the risk of foodborne illness. Clean counter tops, containers and utensils with soapy water, as follows: –Scrub dirt and rinse with water –Wash with soapy water –Rinse –Sanitize with dilute bleach solution
Practical exercise Surface cleaning
Surface cleaning demonstration Four groups –Wipe only –Rinse only –Detergent wash –Detergent + scrubbing Use Vericleen test kit to check for cleanliness
Why is worker training a priority? Workers are sometimes the last/only people to handle the food before the consumer Workers need to be aware of food safety issues and their impact Effective training results in better employees and safer foods
Training workshop evaluation Give a grade from 1 (worst) to 10 (best) Was this training useful to you? Was the training engaging enough? Will you use the things you learned today in your daily work?