1
The removal of moisture in a food product
Dehydrating
Removing all the oxygen from a food package
Vacuum packaging
True or false: Ethylene is the gas that speeds ripening and color development in citrus and bananas.
True
Why is food preserved? (3 reasons)
ensure abundant and diverse food supply throughout the year
prevent microbial growth
maintain taste and texture
make food products more convenient
What temperature does food freeze at?
The _________________ pH of a food item, the longer the food will keep.
Lower
Microbial conversion of carbohydrates to organic acids is an example of a _______________ change.
chemical
What temperature are refrigerators set at?
40 degrees
When the level of salt is increased, the osmotic pressure______________ while the water activity__________________. (utilizing the words, increases or decreases here)
increases, decreases
Name 3 acidic foods
Grains, eggs, fruits, tomatoes, milk
What gas is most frequently used for immersion freezing?
Nitrogen
What fruit releases ethylene gas, causing it to ripen faster?
banana or citrus
Name 4 things that can influence food perishability rate.
pH, moisture, temperature of product, oxygen level, physical characteristics
Name 2 physical changes of food due to microbial activity
slime formation, undesirable odors or flavors, color changes
What are two preservation techniques that create a high osmotic pressure?
What additives are used to preserve foods?
salt, spices, sugar, smoke, acid
Describe how acidity influences the perishability of food.
more acidic, lower pH, slower food deteriorates
bacterial growth favors neutral pH 7.0
Describe 2 of the food preservation techniques used by early American colonists. Be specific.
utilizing winter months, springhouses, root cellars, drying, salt curing, ect.
Compare and contrast too much moisture and too little moisture on food preservation.
Too much moisture- microorganism thrive in this environment, not preserving food
Too little moisture- dehydrate the product unintentionally and lower the quality
According to the USDA, how long can cookie dough be kept in the fridge?
2-4 days