Post on 15-Apr-2017
Decisions, Decisions, Decisions
Paper
Cardboard
Rigid Plastics
Flexible Plastics
Biologically
Synthesized Plastics
Glass
Aluminum
Tin
Stainless Steel
Wax
Ceramics
Wood
Tetra Paks
Choosing a Packaging Type
Cost
Storage size
Frozen
Fresh
Shelf-stability
Expansion after
storage
Recyclability
Effects on the product
Shape
What food product is
being packaged
Where the food
product will end up
Chemistry of Food Packaging
Allows us to determine what type of packaging will prevent food
products and drink products from environmental harm.
Organoleptic properties through exposure to air and light.
Harmful pathogens such as Escherichia coli and Salmonella spp.
Food packaging can also be a source of harm to foods and the
consumer.
Some food packages can leach harmful compounds into foods and drinks.
Chemical structure can also determine what type of package is best
suited for recycling, composting, or enzymatic decomposition.
Food Packaging Features
1) Reactivity of the food
product to the
environmental
moisture and thermal
leaps
2) Protection against
crashes
3) Safety and hygiene
Preservation and Protection
Protection
Defense of the packaged
product and the whole
food product from
external attack
Powders
UV rays
Thermal leaps
Moisture
Crashes
Compression
Vibrations
Preservation
Against microbial agents
Degrading microorganisms
Pathogenic bacteria
Correlated degraded
chemical reactions
Plastics
Plastics have a 37%
market share of food
packaging materials.
Includes both ridged
and flexible plastics
Used widely by many
manufacturers to store
multiple types of food.
Fresh
Frozen
Shelf-stable
Refrigerated
Classifications of Plastics
Rigid and semi-rigid containers
Flexible Food Packaging
Polycoupled Food Packaging
Plastic components for plastic and hybrid packages.
Polystyrene
Mainly known as
“Styrofoam”.
Can be easily molded to
fit almost any shape.
Used widely as a tray for
wrapping fish, meats,
cheeses, etc.
Can leach di(2-
ethylhexyl)adipate (DEHA)
into foods.
DEHA is known to cause
cancer in the liver (in vivo
mice trials).
Bisphenol A (BPA)
Used to produce
polycarbonate plastics,
epoxy resin for cans, toys,
and microwave
containers.
Heat coupled with acidic
or basic foods hydrolyzes
the ester bonds holding
the BPA molecules
together, allowing them to
leach into foods.
Polyethylene Terephthalate (PET)
PET bottles are known for their ability to prevent oxidation of
the liquids contained within.
They are highly resistant to the sorption of aroma compounds.
Tests have been done to compare the sorption of aroma
compounds comparing PET bottles to bag-in-box (BIB) multilayer
flexible plastics and another study comparing PET bottles to
linear low density polyethylene (LLDPE) and polycarbonate (PC)
films.
Bioplastics
Bioplastics obtain their carbon from renewable sources.
“Biodegradable polymers are polymers that are capable of
undergoing decomposition into CO2, CH4, H2O, inorganic
compounds or biomass through predominantly the
enzymatic action of microorganisms.” (Peelman, et al,
2013)
Bioplastics can also be compostable.
Polylactic Acid (PLA)
Lactic acid can be obtained on the basis of renewable starch
containing resources by fermentation, or by chemical synthesis of
non-renewable resources.
Sources can be from starch-rich products such as corn and wheat.
Starch is converted to glucose and then subsequently fermented into
lactic acid, and from there into L-lactide.
Also known as polylactide, it is capable of decomposing at higher
rates than petroleum-based counterparts.
Polyesteracetal (PEA)
1,3-dioxolan-4-one (DOX) can be obtained by combing natural gas with wood/cellulose, producing methanol. With the addition of water, carbon monoxide, and formaldehyde, you will achieve the product DOX.
Synthesized by combining L-lactide and DOX.
Degrade in salt solutions easier and at a higher rate than PLA.
Degradation does produce 85 mg formaldehyde, but at a strength that is equivalent to 9 pears.
Polyhydroxyalkanoates (PHA)
“The polyhydroxyalkanoates (PHA) family are biodegradable
thermoplastic polymers, produced by a wide range of microorganisms.
The polymer is produced in the microbial cells through a fermentation
process and then harvested by using solvents such as chloroform,
methylene chloride or propylene chloride.” (Peelman, et al. 2013)
New vs. Recycled
There is an increasing desire
for renewable resources as well
as reusable resources.
Recycled products are
becoming increasingly more
common in the packaging
industry.
Their increased relevance in
the packaging industry is due to
the fact that more and more
consumers are becoming aware
of their “footprint” during their
lifetime.
PET Bottles
A study was conducted using virgin glass bottles, virgin PET bottles, and recycled PET bottles (respectively in table below) concerning the aging of wine.
Esters, alcohols, and acids were tested at times of 0, 5, 9, and 12 months.
0 Months 5 Months 9 Months 12 Months
Esters 15.0+/-0.5
mg/L for all
• 13.4
• 22.8
• 22.6
• 26.6
• 26.9
• 26.9
• 26.4
• 24.1
• 21.9
Alcohols 96.6+/-2.4
mg/L for all
• 96.1
• 68.7
• 74.5
• 66.1
• 64.0
• 64.2
• 52.5
• 50.7
• 55.0
Acids 8.3+/-0.2
mg/L for all
• 4.8
• 7.8
• 8.2
• 8.1
• 8.1
• 8.1
• 7.8
• 7.8
• 6.7
Pros
Bioplastics
Capable of a “green birth” – they don’t require fossil fuels to
produce.
Bioplastics are capable of degradation by enzymatic action and
have a shorter biodegradable timeline (typically).
Plastics
BPA has a wide range of uses; from food packaging to toys to water
pipes.
Polystyrene is capable of being molded into a plethora of different
shapes, allowing its use as a container in the food packaging
industry to be nearly unlimited.
Plastics Cons
BPA has been associated with moderate estrogenic
activity and can influence reproduction.
BPA has also been associated with disruption of
thyroid hormones, proliferation of prostate
cancer cells, and blocking testosterone
production.
Polystyrene has shown that it releases DEHA into
foods, potentially causing liver cancer.
Bioplactic Cons
Bioplastics
Brittleness (due to high glass transition and melting temperatures),
stiffness, poor impact resistance, difficult heat stability, high water vapor
and oxygen permeability, and thermal instability are finally also factors
limiting the application of PHA films as food packaging (Peelman, et al).
PLA isn’t confirmed to biodegrade at a faster rate compared to its fossil
fuel-based counterparts. It is recommended that PLA go through industrial
composting with the addition of enzymes.
“Because of the hydrophilic nature of starch and cellulose, packaging
materials based on these materials have a low water vapor barrier, which
causes a limited long-term stability and poor mechanical properties
(sensitive to moisture content). Other drawbacks are bad processability,
brittleness and vulnerability to degradation”
Costs are greater for bioplastics due to lack of availability and lack of land
for use in production.
Conclusions
When choosing a food packaging container, it is
vital to choose the right one.
Some containers may leach harmful chemicals
into your product.
Consumers are becoming more conscious of
recyclable materials, increasing the demand for
biodegradable and reusable containers.
References Dombre, C., Rigou, P., Wirth, J., & Chalier, P. (2014). Aromatic Evolution of
Wine Packed in Virgin and Recycled PET Bottles. Food Chemistry, (176), 376-
387.
Fasano, E., Bono-Blay, F., Cirillo, T., Montuori, P., & Lacorte, S. (2012).
Migration of phthalates, alkylphenols, bisphenol A and di(2-ethylhexyl)adipate
from food packaging. Food Control, 27(1), 132-138.
Martin, R., Camargo, L., & Miller, S. (2014). Marine-degradable polylactic
acid. Green Chemistry, 16(4), 128-141
Muncke, J. (2012, October 5). Food Packaging Materials. Retrieved April 7,
2015, from http://www.foodpackagingforum.org/food-packaging-
health/food-packaging-materials
Peelman, N., Ragaert, P., Meulenaer, B., Adons, D., Peeters, R., Cardon, L.,
Van Impef, F., Devlieghere, F. (2013). Application of bioplastics for food
packaging. Trends in Food Science & Technology, 128-141.