Food Packaging

Panera and Starbucks use two different polyolefin plastics for their cold drinks. Name each.

(1) Panera cold drink cup is #5 PP (Polypropylene) (2) Starbuck cold drink cup is #1 PET (Polyethylene Terephthalate)

List the 7 types of plastics used in food packaging according to their recycling number (in order).

1 = PolyEthylene Terephthalate (PET); 2 = High-Density PolyEthylene (HDPE); 3 = Polyvinyl chloride (PVC); 4 = Low-Density PolyEthylene (LDPE); 5 = PolyPropylene (PP); 6 = PolyStyrene (PS); 7 = Other

Name three potential hazards of Modified Atmosphere/Controlled Atmosphere (MA/CA) packaging.

1. Aggravation of certain physiological disorders, 2. Irregular ripening 3. Off flavor development. e.g anaerobic respiration leading to undesired products like ethanol and acetaldehyde 4. The growth of anaerobic pathogens

Describe the difference between active and intelligent packaging, and give one example of each.

Active packaging interacts with food or headspace to extend shelf life (e.g., oxygen scavengers). Intelligent packaging monitors product condition (e.g., time-temperature indicators).

List three mechanisms by which packaging can extend food shelf life.

Barrier protection (oxygen/moisture exclusion), modified atmosphere packaging, active packaging (oxygen scavengers or antimicrobials).

Discuss the principles and benefits of controlled atmosphere packaging.

CAP maintains specific gas concentrations throughout storage to slow respiration, microbial growth, and oxidation, commonly used for fresh produce.

Name four advantages of using glass as a packaging material.

Chemically inert, odorless, high storage stability, may be transparent, easy to open and reseal, can be used with vacuum operations.

What are the four principal functions of a food package?

Communication, Protection, Convenience, Containment

What are 3 common can seam defects?

Droop, false seam, and cut over

From the inside to the outside, list the components of the four layers found in the "tin" can.

Enamel (inside), Tin, Tin-iron alloy, Steel (outside)

Name four commonly used coatings for steel cans.

Epoxy, phenolic, acrylic, vinyl and oleoresins (REF: Food and beverage can coatings: A review on chemical analysis, migration, and risk assessment).

Compare glass and plastic packaging in terms of barrier properties and recyclability.

Glass is impermeable to gases, offers excellent barrier properties, and is highly recyclable but heavy; plastics vary in barrier properties, are lightweight and versatile, but may have permeability and recycling challenges.

What do the acronyms HDPE, PE, PP, LDPE, PS, PVC and PET stand for?

HDPE=High-density polyethylene, PE= Polyethylene, PP= polypropionate, LDPE= low-density polyethylene, PS= PolyStyrene, PVC= PolyVinyl Chloride, PET= polyethylene terapthalate

A barrier film is composed of three polymers. From the outside to the inside of the package give the correct order of the following polymers of this film.

Heat barrier layer (outer), gas barrier layer (middle), and Heat seal layer (inner)

Name three possible causes of a false seam on a can.

Incorrect seamer setup, damaged flange or cover curl, and excessive seaming compound

Name four functions of edible film.

Inhibit mass transfer, carry ingredients, improve mechanical integrity, improve appearance, extend shelf-life

Name 3 reasons for using a retortable pouch.

Less weight of package, less storage space occupied on shelf, better heat transfer, less energy required to heat, less cost for package and transport, easier to empty, shorter processing time, higher quality (due to shorter processing time)

Give three advantages of coextrusion films over laminates.

Lower cost, thinner, one step process, layers do not separate.

Describe Modified Atmosphere Packaging (MAP) and explain how it extends shelf life.

MAP involves altering the gas composition inside a package, typically reducing oxygen and increasing carbon dioxide or nitrogen, to slow microbial growth, enzymatic activity, and oxidation. This helps maintain quality and extend shelf life, particularly for meats, fresh produce, and bakery products.

Compare MAP and active packaging in terms of mechanism and application.

MAP modifies the package atmosphere at sealing, while active packaging interacts dynamically with the food or environment (e.g., oxygen scavengers) to extend shelf life.