Unit 2 Flashcards
What are the 4 methods of increasing food productivity
Agricultural chemicals
Aquaculture
Irrigation
Biotechnology
Plants and animals modified by genetic engineering are called _____
Transgenic
What is the difference between the outcome of genetic engineering vs traditional breeding?
In genetic engineering, only the desired gene is transferred whereas in traditional breeding, other genes may be transferred
3 pros of food biotechnology
Minimize food shortages
Reduce environmental impact
Improve nutritional health
What is organic farming
Farming without the use of certain pesticides, fertilizers, antibiotic growth hormones, and GMOs
What are some farming practices that promote sustainability
Crop rotation Covering crops (prevent soil erosion) Using renewable resources Enhancing biodiversity Compost for soil fertility Balancing host/predator relationships
True or false: scientific evidence strongly supports that organic food is much healthier than normal food
False
A product must contain at least ___% organic ingredients to be certified organic
95%
What is food processing
Conversion of raw plant and animal tissue into convenient and practical forms for consumption
What are six methods of Food processing
Moisture removal Heat treatment Low temperature treatment Acidity control Traditional non-thermal processing Non-thermal processing innovations
What is moisture removal
Removing biologically active water in an attempt to stop microorganism growth (drying, dehydration)
What is heat treatment
Pasteurization, blanching, canning, baking, cooking, sterilization
What is low Temperature treatment
Cold storage (fridge, freezer)
What is acidity control
Controlling the pH of the food
What is traditional nonthermal processing
Chemical additives or food packaging
What is nonthermal processing innovations
Irradiation, high pressure
What are food processing aids
Specific food additives like gums, natural colouring agents, enzymes and sweeteners
What is food preservation
Do use of specific processing techniques to reduce spoilage, microorganisms in food and to improve safety and shelf life
What is one of the primary causes of food spoilage
Biologically active water in tissues
What are the 3 classes of food preservation
Chemical
Biological
Physical
Salt and other preservatives such as _____ reduce water activity in foods
Potassium sorbate
What are preservatives
Additives that maintain the freshness of foods
What is fermentation
A biological method of preservation that involves bacteria or yeast acting on the carbs of a food.
Lowers the pH, resulting in taste changes
What is the oldest form of food preservation
Drying
___ needs 15% moisture to survive
Bacteria and mold
___ needs 20% moisture to survive
Yeast
What is oven/plate drying
Food spread on shelves in kilns or drying rooms. Hot air is blown over and through the food
What is spray drying
Used for liquid products
Spray noss sprays very tiny droplets of the product into a hot chamber and the high temp immediately dries the droplets
Dried droplets are collected from the bottom of the chamber
What is drum drying
Used for starches like mashed potato flakes and instant oats
Product is evaporated and then poured over large heated drums that rotate until the product dries into thin layers on the surface
Product is further ground to obtain powder
What is freeze drying
Food is frozen, then placed in a vacuum where the ice is evaporated via sublimation
What is the most effective drying method and why
Freeze drying, because it is not exposed to high heat so more vitamins remain intact
Name 3 types of drying pretreatments
Physical - cracking skin of fruits
Blanching - deactivates enzhmes that cause browning
Chemical - sulfur solutions to prevent browning and prevent loss of vitamin A and C
What are 4 methods of thermal processing
Sterilization
Pasteurization
Blanching
Canning
What is sterilization
Complete destruction of micro organisms through extended heat treatment or use of chemicals
Food is exposed to wet heat to reach temp of 121°C for 15 min
What is the shelf life of commercially sterile foods
2+ years
What is pasteurization
Heating food to a specified high temperature for a short time
Between 80-90°C