Food Packaging

Function of food packaging

• preserve quality

• prevent contamination

• barrier to environment

• convenienve

• adequate storage

• prevent/indicate tampering

• communicate information

• marketing

Key barrier properties

• water vapor transmission rates

• oxygen transmission rates

• light transmission (especially UV transmission)

Edible films

A thin layer of edible material formed on a food as a coating or placed on/between food components

• sugar shell on individual coated candies

• sausage casings

• edible waxes on fruits

Purposes:

• inhibiting migration of moisture, gases, aromas

• improving mechanical integrity or handling characteristics

Laminates

1. Polyethylene: protects against external humidity.

2. Paper: stability and strength.

3. Polyethylene: adherence layer.

4. Aluminum foil: oxygen, odor, and light barrier.

5. Polyethylene: adherence layer.

6. Polyethylene: product protection.

Two general purposes for controlling packaging atmosphere

• reduce spoilage and contamination

• enhance shelf-life

Specific effect of controlling oxygen

maintains respiration, color, inhibits anaerobic microbes

Specific effect of controlling carbon dioxide

retards ripening/respiration, inhibits microbial growth

Specific effect of controlling water vapor

caused by a hermetic seal; prevents molding?

Specific effect of controlling ethylene

controls ripening

Specific effect of controlling nitrogen

addition removes O2, limiting rancidity

Vaccuum packaging

removes O2

Sous vide

vacuum packaging in sealed plastic bags and then cooking in temperature-controlled water

Cook-chill

plastic bag filled with hot food, displacing air, chilled rapidly

Flexible packaging

non rigid containers, sometimes resealable

• stand-up pouches, tubes, zippered bags

Modified atmosphere packaging (MAP)

initial replacement of air with CO2 or N2

Controlled atmosphere packaging (CAP)

continuous control of atmosphere

Concerns of manufacturers regarding packaging

• throughput of packaging lines at processing plants

• cost of materials

• consumer convenience

• product safety

• migration from packaging materials

• product shelf-life

• environmental concerns

Primary

direct food contact

Secondary

holds primary containers (no direct food contact)

Tertiary

• bundles secondary containers

• minimizes denting, crushing of primary containers when mishandled

Active Packaging

components that react based on the internal environment

• oxygen absorber packets

Hermetic seal

an air tight seal provided by cans or glass jars