Food Processing and Preservation (Processes)

Quiz bowl practice set

Purpose of Processing Food

To preserve food and create a specific desirable food product

Food Spoilage

Perishability of raw foods through microbial growth, enzymatic reactions, and chemical changes (mainly through factors of water, temp, and pH)

Unit Operations

Describes the processing step of a product, like in a factory (i.e. heat exchange, evaporation, drying, and material handling)

Basic Principles of Food Processing

1) moisture removal

2) heat treatment

3) low-heat treatment

4) thermal processing

5) nonthermal processing (traditional & nontraditional)

6) acidity control

Moisture Removal

The removal of water from food to lower its moisture content to inhibit food spoilage. Done by adding solutes, like sugar and salt

Heat Treatment

Process of inactivating pathogens and spoilage microorganisms and enzymes, i.e. blanching and pasteurizing

D-value

The value of heat resistance. The specific time at a specific temperature for a specific food to destroy 90% of the population (one log) of a specific MO.

12D Concept

The D-value to destroy 90% of C. Botulinum at a 12 log reduction: ensures safety of low acid foods

TDT (Thermal Death Time) Studies

Done to determine an organism's heat resistance (D-value) in a specific product to develop a process for that product

Low-Temperature Treatment

Done to a) slows spoilage reactions, b) freezes the water in food to reduce aW i.e. refrigerating

Acidity Control

The more acid present in a food, the lower the pH becomes, lowering the potential of microbial spoilage, and requires less heat treatment

Traditional Nonthermal Processing

Chemicals added to food for preservation to control aW and extend shelf-life through packaing

Types of Traditional Nonthermal Processing

1) modified atmosphere packaging (MAP)

2) controlled atmosphere storage (CAS)

3) nitrogen flush packaging

4) vacuum packaging

Innovative Nonthermal Processing

Refers to new technologies that preserve the food supply without raising the temperature; to eliminate thermal degradation of food quality

Blanching

Process used to inactivate enzymes and set color

Pasteurization

Process used to inactivate pathogens (e. coli) and vegetative (alive) pathogens

Commercially Sterile

Describes a product free of all pathogens and other microorganisms that could potentially grow in the product

Sterilization

Describes a product that is free of all pathogens and MOs; used mainly for medical purposes