6 Food Preservation Principles Free Online FlashCards

What is the purpose of food preservation?

Preservation extends food’s useful life by slowing or preventing changes that make it unsafe or unacceptable to eat.

What are four causes of food deterioration?

Microbial growth, food enzymes, chemical reactions, and physical changes such as moisture loss can all cause deterioration.

What does water activity measure?

Water activity measures how much water is available for microbial growth, not simply how much water the food contains.

Can appearance, smell, or taste prove that food is safe?

No. Pathogens can grow or produce toxins without visible or detectable spoilage, so sensory checks cannot establish safety.

What is a hurdle approach to preservation?

Hurdles are multiple unfavorable conditions used together to make microbial growth more difficult.

What is an important limit of freezing?

Freezing stops most microbial growth but does not sterilize food; refrigeration slows deterioration.

Why are many vegetables blanched before freezing?

Blanching inactivates enzymes that could cause quality loss during frozen storage; excessive blanching can also harm texture and flavor.

How does pasteurization differ from sterilization?

Pasteurization reduces harmful microbes in particular foods, but it is not the same as sterilization.

Why do low-acid foods require pressure canning?

Low-acid foods require pressure canning with tested procedures because boiling-water temperatures are insufficient to control spores that can cause botulism.

How does drying help preserve food, and what can undermine it?

Drying removes water and lowers water activity, restricting microbial growth. If dried food absorbs moisture during storage, mold may grow.

How do acidification and fermentation help preserve food?

Acidification lowers pH to inhibit many microbes; fermentation can produce acids or other inhibitory substances.

When can salt or sugar act as a preservative?

High salt or sugar concentrations reduce available water and can inhibit microbial growth. Sugar used only for sweetness is not necessarily a preservative.