This document discusses food contamination and spoilage. It identifies key stages where contamination can occur, such as during food handling, preparation, and storage. Temperature, moisture levels, insects, and microbes can all lead to contamination if safe practices are not followed. Bacteria growth is favored between 4-60 degrees Celsius and killed at 100 degrees. Contamination can cause foodborne illnesses with symptoms like nausea, vomiting, and diarrhea. Enzymes from bacteria can also cause food to spoil faster by producing a slimy coating on raw foods. Proper temperature control and hygiene are important to prevent contamination and spoilage at all stages of food production.

1. FOOD SAFETYCHAPTER 3

2. ObjectivesHow food contamination occursWhy food contamination occursIdentify stages of food preparation where food spoilage occursDescribe and apply safe practices in stages of food preparation

3. FOOD CONTAMINATIONSection 1

4. Food ContaminationFood poisoning occurs when food is not prepared or cooked safely.Some symptoms of food poisoning are vomiting, diarrhoea and fever.Food can be contaminated by physical means, microbiological modes and enzymatic action.

6. Temperature of FoodTemperatures ranging from 4 to 60 degrees Celsius favour bacteria growth.Bacteria is killed at 100 degrees Celsius and inactive at -18 degrees Celsius.Hot food should hence be kept hot and cold food be kept cold so that bacteria is destroyed and bacteria does not grow.

7. Presence of MoistureMicro-organisms require moisture to grow and would multiply quickly when moisture content is high.People handling food with high moisture content can cross-contaminate micro-organisms from unclean hands.Examples of food with high amounts of moisture are raw meat, seafood, vegetables and fruits.

8. Presence of InsectsInsects and their droppings carry many micro-organisms that are invisible to humans.When they get in contact with food, the area would be contaminated with bacteria and become unhygienic.

9. Microbiological contaminationMicrobiological contamination can result in foodborne illnesses.Symptoms include nausea, vomiting, stomach pain, diarrhoea and fever.

10. Microbiological contamination

11. Enzymatic ActionEnzymes are substances found naturally in animals and plants. Enzymes of humans help break down food into simpler forms.Enzymes of bacteria in raw food help liquefy the food to produce a slimy coating that causes food to spoil faster.However, enzymatic action only affects the appearance of the food.

12. FOOD SPOILAGESection 2

13. Food SpoilageFood spoilage can occur anytime such as during food handling, food preparation and food storage.Wrong practices at any stage can introduce micro-organisms into the food.

15. Food Handling

16. Food Preparation

17. Food Storage

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