Food processing and Safety Flashcards
Benefits of food processing
Extend shelf life
Increase usefulness
Destroy anti-nutritional factors
Detrimental effects of food processing
Nutritional losses (vitamin destruction, fat oxidation) Quality losses (texture change, colour change) Generation of undesirable compounds (trans fats)
What is food spoilage?
The process in which food deteriorates to the point that its inedible or has reduced quality
What are the 4 primary causes of spoilage?
- Microorganisms
- Insects
- Chemical
- Physical
What are the 5 factors affecting microbial activity?
- Temperature (Psychrophi,es, Mesophiles, Thremophiles)
Acidity (most spoilage organisms grow best at a neutral pH)
Moisture (Aw describes water availability)
Oxygen (Aerobic, Anaerobic, Facultative, Microaerophilic)
Physical Form (affects meat on the surface)
List 5 Deteriorative changes
Slime (large numbers of bacteria) Sour (bacteria produce acids Rancid (bacteria oxidizes fat Putrid (bacteria attack protein)j Gas (bacteria produce carbon dioxide)
What are the two types of chemical food spoilage
Oxidative rancidity (fat oxidation when exposed to air) Discolouration (changes pigment)
What causes physical food spoilage?
Light exposure Dehydration Freezer burn Drip Absorption of off-flavour
What is food preservation?
Actions to maintain desired properties of food for as long as possible
4 advantages of food preservation
We get materials out of season
It prevents food spoilage
Enables the availability of food at distant places
Storage period increases
4 disadvantages of food preservation
Processed foods often lose nutrients
Milled and polished rice results in loss of vitamin B and iron
Loss of nutrients in flour
Changes in taste
What is pasteurization
Heat treatment to inactivate enzymes and kill heat sensitive microorganisms that cause spoilage
What is sterilization
Extreme heating to kill yeast mould vegetable bacteria and spore formers
What is drying
A process that removes moisture from the food and inhibits the growth of bacteria
What is blanching
Spending a short time in boiling water before freezing or drying
What effects does heat processing have on nutrients
Protein, carbs, water soluble vitamins
Protein- enzyme inactivation, loss of amino acids
Carbs- starch gelatinization, increased digestibility
Vitamins- loss of C and B
What is irradiation
Invisible photons of electromagnetic energy used to kill pathogens
Referred to as cold pasteurization and has negative effects on food quality
What is high pressure processing (HHP)
HHP is a process where food is subjecting to extreme pressure to kill bacteria
Purpose of packaging
Packaging protects food during storage and distribution as well as being visually stimulating to customers
What 3 factors influence consumers purchasing decisions
Appearance
Flavour
Texture
Spectrophotometry
Measuring reflected light at various wavelengths
5 basic tastes
Sweet Salty Sour Bitter Umami
What is a foodborne illness
Any illness resulting from the consumption of contaminated food, pathogens in the food, or natural chemical toxins
Food intoxication vs infection
Food intoxication- food affected by natural toxins or having toxins from a pathogen
Food infection- bacterial invasion of food tissue
