NATS 1560 Test 2 Flashcards
Food preservation
processing of food to delay and minimize spoilage
Main causes of spoilage
microbes (bacteria, yeasts, molds), enzymatic reactions, oxidation
Variables that cause spoilage
moisture, temperature, acidity, exposure to oxygen
Food Preserving Methods
Pre-industrial
Industrial
Pre-Industrial
Drying
Smoking
Salting
Sugaring
Pickling
Industrial
Canning
Refrigeration and freezing
Pasteurization
Irradiation
Preserving additives
Vacuum packaging
Dehydration
Removal of water
Traditionally: open air and heat
Combination with salt and smoke
Sugaring
Reduces moisture available for microbial
Ancient Greeks and Romans Sugaring
Used honey and concentrated grape juice
Asia Sugaring
Sugar canes used as a drug, spice and luxury item
Pickling and Curing
Sealed in container to grow beneficial bacteria and yeasts
Development of lactic acid and aromatic compounds
History of Canning
1810: Nicholas Appert created sealed jars with cork lids and wax
1850: Industrial canning and long-distance shipping
Late 1800s: glass jar and air-tight lids
Canning
Foods are contained airtight and sterilized with heat
To prevent botulism
low acid foods heated at 121 degrees celsius for 10-20 min
Refrigeration
Slows down microbial growth and enzymatic action
Refrigeration History
Early 1900s: Ice-blocks from industry in Canada and US, refrigerated trains and cargo
Timeline of Refrigeration
1850: invention of heat pump and mechanical refrigeration
1870: ammonia-refrigerated unit and cold-storage plants
1910: large electric refrigerator
1950: electric became affordable
Freezing
Slows down growth of microbes and enzyme action
Types of Freezing
Immersion
Freeze-drying or lyophilization
Immersion Freezing
Brine, sugar, water, antifreeze and centrifuging to remove liquid
Freeze-drying
Placed in vacuum chamber, slightly heated and water removed
CFCs
Used as refrigerants and aerosol propellers