What are convenience foods?
Convenience
foods are used to shorten the time of meal preparation at home. Some foods can be eaten immediately or after
adding water, heating or thawing etc.
Convenience
food, or tertiary processed food, is commercially prepared food designed for
ease of consumption. Although restaurant meals meet this definition, the term
is seldom applied to them. Convenience foods include prepared foods such as
ready-to-eat foods, frozen foods such as TV dinners, shelf-stable products and
prepared mixes such as cake mix.
Bread,
cheese, salted food and other prepared foods have been sold for thousands of
years. Other kinds were developed with improvements in food technology. Types
of convenience foods can vary by country and geographic region. Some
convenience foods have received criticism due to concerns about nutritional
content and how its packaging may increase solid waste in landfills.
Initiatives have occurred to reduce the unhealthy aspects of commercially
produced food and fight childhood obesity.
Convenience
food is commercially prepared for ease of consumption. Products designated as
convenience food are often sold as hot, ready-to-eat dishes; as
room-temperature, shelf-stable products; or as refrigerated or frozen food
products that require minimal preparation (typically just heating) Convenience
foods have also been described as foods that have been created to "make
them more appealing to the consumer." Convenience foods and fast foods are
similar, because the development of both occurred to save time in the
preparation of food. Both typically cost more money and less time compared to
home cooking from scratch.
Types of convenience foods:
Convenience
foods can include products such as
Ø Candy.
Ø Beverages
such as soft drinks, juices and milk.
Ø Fast
food.
Ø Nuts,
fruits and vegetables in fresh or preserved states.
Ø Processed
meats and cheeses.
Ø Canned
products such as soups and pasta dishes.
Ø Frozen
foods.
Ø Chips
and cookies.
Ø Dehydrated
foods etc.,
Candy Packaging:
Prior
to the 1900s, candy was commonly sold unwrapped from carts in the street, where
it was exposed to dirt and insects. By 1914 there were some machines to wrap
gum and stick candies, but this was not the common practice. After the polio
outbreak in 1916, unwrapped candies garnered widespread censure because of the
dirt and germs. At the time, only upscale candy stores used glass jars. With
advancements in technology wax paper was adopted, and foil and cellophane were
imported from France by DuPont in 1925. Necco packagers were one of the first
companies to package without human touch.
Packaging
preserves aroma and flavor and eases shipping and dispensation. Wax paper seals
against air, moisture, dust, and germs, while cellophane is valued by packagers
for its transparency and resistance to grease, odors and moisture. In addition,
it is often resealable. Polyethylene is another form of film sealed with heat,
and this material is often used to make bags in bulk packaging. Saran wraps are
also common. Aluminum foils wrap chocolate bars and prevent transfer of water
vapor, while being lightweight, non-toxic and odor proof. Vegetable parchment
lines boxes of high-quality confections like gourmet chocolates. Cardboard
cartons are less common, though they offer many options concerning thickness
and movement of water and oil.
Packages
are often sealed with a starch-based adhesive derived from tapioca, potato,
wheat, sago, or sweet potato. Occasionally, glues are made from the bones and
skin of cattle and hogs for a stronger and more flexible product, but this is
not as common because of the expense.
Beverages Packaging:
The
packaging requirements for all types of beverages are:
•
Absolutely leak-proof and prevent contamination
•
Protect the contents against chemical deterioration
•
No pick up of external flavours
•
Be hygienic and safe
•
Retain carbonation in the case of carbonated beverages
•
Economical, easy to use and dispose
•
Good aesthetic appearance
Beverages
are classified into Alcoholic and Non-Alcoholic beverages.
Packaging Materials for
Non-Alcoholic Beverages:
Key
parameters to be considered when selecting a packaging system are:
•
Process
•
Distribution, shelf-life requirements, legislation
•
Product composition and quality as produced and at full shelf-life
•
Product protection required during storage, distribution and retail sale
•
Pack size, printing options, display etc.
•
Packing system concept, automation options, ability to integrate with existing
and/or future systems
•
Consumer appeal, image of product and packing
The
different packaging materials used are:
•
Glass Containers: The use of glass bottles for the packaging of fruit beverages
was widespread although the hot-fill/hold/cool process had to be applied with
care to avoid breakage of the containers. Glass is still the preferred
packaging medium for high quality fruit beverages. However, over recent years,
an increasing proportion is being packed aseptically, into cartons.
The
improvements that have occurred in glass bottle packaging are:
•
Light weight
•
Surface coating to increase abrasion resistance
•
Use of wide mouth containers fitted with easy-open-caps.
•
Metal Containers: Tinplate cans made of low carbon mild steel of 99.75% purity,
coated with tin with easy open ends are used. These tinplate containers are
either 3 piece or 2 piece containers. They are lacquered internally to prevent
corrosion.
•
Plastic Containers: Fruit juices contain organic substances, which are
sensitive to bacterial contamination. Packaging of such products is done
through hot filling, to achieve extended shelf-life, PET bottles are usually used
for hot filling applications. Special features are added to the containers
through design and manufacturing process. The package is heat-set in order to
improve the temperature resistance of the containers. PET resins with a higher
Tg (glass transition) temperature and/or a faster rate of crystallisation are
used. Normally hot-filled PET bottles are designed about 1.5 times heavier than
cold-filled bottles. Reinforcing ribs and grooves are also provided along the
circumference and base of the bottle. After filling and capping operations, the
liquid continues to cool, which results in formation of vacuum. The bottle wall
can deform under the influence of vacuum, and this problem is overcome by
providing vacuum panels in the container side wall. Generally, lower levels of
PET co-polymer are preferred and intrinsic viscosities of about 80 are
acceptable. Flexible plastic packages offer economic savings over conventional
glass and metal containers but they are permeable to oxygen. Therefore, it is
critical to select a flexible package that minimizes the permeability to
oxygen. Flexible laminated pouches like metalized polyester/polyester/
polyethylene are used for hot fill packaging method without retorting for
acidic fruit juices. These are used either as flat pouches or stand-up pouches.
However, the shelf-life of the product in these pouches is limited.
•
Aseptic Packages: Ready to serve fruit beverages and fruit pulps /
concentrates, packed in aseptic packages provide excellent protection for fruit
juices / pulps. These aseptic packages are made by combining thermoplastic with
paperboard and aluminium foil. Their multi-layered construction enables the
carton to protect the contents from various factors responsible for spoilage.
The aluminium foil layer is a strong barrier for O2 and light. The inner
plastic layer made of polyethylene makes it possible to seal through the
liquid. The outer paper layer provides stiffness making it possible for the
cartons in a brick shape, thus, enabling maximum utilization of available storage
and transportation space. Excellent graphics are possible leading to good
display and shelf appeal and also providing information regarding the product.
The aseptic process makes the product bacteria-free before being packaged. To
provide convenient access to the contents, beverage cartons offer a variety of
opening devices. A familiar opening feature of the pack is the drinking straw,
which is attached to the package. Some recent trends are pull-tab opening,
which can be readily detached from a pre-punched hole without compromising the package
integrity. Also, custom designed caps and closures can be incorporated on
beverage cartons for easier pouring and for enhancing the brand image. Also,
the beverage cartons are now available in new prisma shape, which is
comfortable to hold, and the unique shape offers maximum display effectiveness
and high space efficiency. These packs are shelf-stable at room temperature and
the shelf-life and nutrient composition of the fruit juice is influenced by the
barrier properties of the tetrapak.
•
Bag-in-Box System: It consists of a collapsible bag within a rigid container, a
filling machine to introduce the liquid product into the bag and a dispenser to
draw the product out.
Bag:
The outer container can be a box, a crate or a drum. The bag actually consists
of two bags. An inner bag contains the liquid and an outer bag provides the
barrier properties. Both are heat-sealed at the edges. The tubular spout fitted
to the bag aids in filling and dispensing of the product. As little as 3 litres
or as much as 1000 litres, can be packed.
The
bag is the “life” of the system. The bag itself consists of three components:
i.
An inner layer
ii.
An outer layer
iii.
A spout
The
function of the inner layer, the one in contact with the material being packed,
is to provide the bag with seal integrity. The seals are to be strong enough to
withstand constant mechanical and chemical “pressure” for at least twice the
expected shelf-life of the product.
Generally,
the inner layer is not designed for barrier unless the product needs extra
barrier, which the outer layer cannot provide. Plastic films manufactured from
high performance polyethylene, with excellent sealing and puncture properties
are usually used as inner layer materials.
The
function of the outer layer is to provide the bag with barrier commensurate
with the expectation of the shelf-life of the product. In this respect, bag in
box scores over other packaging forms, because unlike other packaging materials
like jars and cans, the barrier property and hence the cost of this packaging
form can be varied. The shelf-life expectations and storage condition play an
important part in determining what the barrier requirements of the outer layer
needs to be. The standard outside layer is a metalized film laminate, which
under standard conditions has an OTR of 1cc/m2 / 24hrs. The spout and cap
assembly are made of injection moulded plastics. The spout is provided with a
flange, which is welded to the bag’s inner layer during bag’s manufacture. The
spout and cap have two functions. They are used to fill the product in the bag
and are also used to dispense the product from the pack. Several spout types
are available ranging from a simple bung like configuration to ones, which can
only be opened on the filling machine. The caps come with various tamper
evident features as well.
Rigid
Containers: The purpose of this container, is to hold the bag during storage, transportation
and use. As is evident, the bag being made from flexible films, is incapable of
being stored and transported by itself. Hence, each bag is individually stored
into rigid outer container post filling. For packs of capacity below 50 litres,
corrugated fibreboard cartons are generally used as the rigid containers. Beyond
that plastics and metal drums are used. For very large bags, 1000 litres, +
polygonal (6-8 faces) corrugated fibreboard containers made from 7 to 9 ply are
used, though there are other alternatives as well.
Ex)
Coffee
While
developing packaging system for coffee the following are to be considered:
•
Moisture vapour ingress
•
Oxygen permeability
•
CO2 and Volatile component egress
•
Grease resistance
The
packaging materials used are tinplate containers, composite containers, glass
jars and flexible plastic pouches. The flexible laminates most widely used are
12μ PET / 2μ Al Foil /
70μ
LDPE and MET PET / LDPE. Aluminium foil lined plastic pouches are most popular having
59% contribution in terms of volume.
Carbonated
Drinks:
Carbonated
drinks contain carbonated water, flavour, colour, sweeteners and preservatives.
CO2
gas from pure source is dissolved in water (amount varies with different types
of beverages). A variety of ingredients like flavouring agents, colouring
agents, preservatives, artificial sweeteners, antioxidants and foaming agents
are then added.
Two
major deteriorative changes that occur in carbonated drinks are the loss of
carbonation and rancidification of essential flavouring oils. The first is
largely a function of the effectiveness of the package in providing a barrier
to gas permeation, while the latter can be prevented by the use of high quality
flavourings and antioxidants, and de-aerating the mix prior to carbonation.
Oxidative rancidity is reduced by the effectiveness of the package in providing
a barrier to gas permeation.
Hence,
the carbonated drink package requires a container that will hold pressure and
not contribute off flavours. For many years virtually all carbonated soft
drinks were packaged in glass bottles sealed with crown cork. In recent years,
non-returnable glass bottles are giving way to refillable bottles. These have a
foam plastic protective label of paper/poly or an all plastic shrink sleeve, as
a safety measure to prevent flying of glass fragments in case of breakage of
these containers. The crown closure has been replaced with a roll-on aluminium
screw cap with tamper proof facility. Among the metal containers, the 3-piece
tinplate containers have been used since long for the packaging of carbonated
beverages. These are being replaced now by 2-piece aluminium cans. These cans
retain the integrity of lacquer better than tin cans. Vinyl, epoxy and vinyl
organosol coatings are used as lacquers for aluminium cans. Epoxy amine
provides good adhesion, colour and flexibility to the can.
Among
the plastic containers, PET bottles are the most preferred packaging material
for packaging of soft drinks.
Soft
drinks have a maximum permissible level of 20ppm for citrus flavoured beverages
and
40ppm
for cola drinks while the water loss is of the order of 1%. Also, the loss of
CO2 through the wall must be allowed for. While increasing thickness will decrease
the rate of CO2 permeation, the cost of the bottle, will also increase and so a
compromise has to be made. Other problems to be considered in plastic
containers are creep and elastic deformation. The polyethylene terephthalate
(PET) bottle satisfies most of the requirements for packaging of carbonated
soft drinks.
Improved
blow moulding techniques and bi-axial stretching have made PET container to be pressurised
due to its strength, dimensional stability and precision. Also, they have a
glass like appearance, good transparency, lustre, chemical inertness and
unbreakability.
The
advantages of PET container are:
•
Superior packaging to product ratio: PET container being 63% and 47% more
energy efficient than glass bottles and aluminium cans respectively.
•
PET bottles are 32% more energy efficient than glass bottles during delivery of
1000 gallons of soft drinks.
•
Glass bottles and Aluminium-cans generate 230% and 175% times more atmospheric emissions
compared to PET.
•
PET bottles contribute 68% and 18% less solid waste by weight compared to glass
and aluminium containers.
•
100 kg of oil is required to produce 1000 1-litre PET bottles as against 230 kg
for 1000 equivalent glass bottles.
•
PET bottles help in fuel saving due to their lower weight.
The
resins used in PET bottles to pack carbonated drinks are of a very special
quality. The PET bottles have to be extremely strong to contain the internal
pressure of CO2 without distortion and expansion. This is obtained by using a
resin, which has high intrinsic viscosity and lower co-polymer levels. Currently,
more than 90% of PET is consumed in food packaging with beverages/drinks
forming nearly 80%.
Packaging Materials for Alcoholic Beverages:
Alcoholic
drinks originated through the action of yeast cells on sugar containing
liquids. Alcoholic drinks are aromatic liquids with a specified alcohol
content. Some kinds contain carbon dioxide, others a quantity of sugar. They are
either fruit/sap based or grain based. They can either be non-distilled or
distilled depending on the volume percentage of alcohol per litre. The border
between the two kinds of drink is about 20%. The different types of alcoholic
beverages are beer, wine, whiskey, brandy etc.
Non
Distilled Alcoholic Beverages:
•
Beer (Grain Based): Beer is made from grains and has low alcoholic content
around 5% by volume. Barley is the chief grain, but rice and corn are also
used. The grains are brewed and fermented and then carbonated with CO2 and
flavoured with hops to give a bitter flavour. Owing to its low pH (about 4.0),
microbial degradation is not usually a problem with beer, and the use of
pasteurization and aseptic cold filtration excludes yeast. However, during storage
beer can undergo irreversible changes leading to appearance of haze,
development
of
off-flavours and increased colour. The oxidation reaction gives beer a
“card-board-like” flavour. Flavour loss is also accelerated in the presence of
light and certain metal ions. The fermentation process consumes oxygen. Also,
brewing reduces the level of oxygen in beer to 40-50 ppb prior to packaging. During
the packaging process, atmospheric oxygen enters the package and the level of oxygen
contamination reaches 250-500 ppb, which corresponds to 0.1-0.2 ml of oxygen
per 335 ml bottle or can. This results in a shelf-life of beer of 80 to 120
days. The oxygen consumption of beer varies with the composition of the beer,
its age, presence of reducing agents, temperature etc.
The
traditional packaging media for beer is the glass bottle sealed with a crown
closure.
Recent
development is the use of PET bottles for packaging of beer. Types of PET beer
bottles used are non-tunnel pasterurised, one way tunnel pasterurised and
returnable / re-fillable bottles.
Beer
needs high performance in both CO2 and O2 barrier compared to PET used in
carbonated soft drinks (CSD) applications. The level required depends on the type
of beer, container size, distribution channels and environmental conditions
(storage time, temperature and humidity levels). Improvements in the barrier
can be obtained via colourants, creating multi-layer bottles and scavengers.
Protection from U. V. light is obtained by adding colourants or U. V.
additives, during the injection moulding stage. Because of the varied requirements
for beer, the resins chosen must provide an adequate barrier, UV protection and
clarity. Beer bottles need strength in order to maintain the CO2 pressure over
a wide range of temperatures. Intrinsic viscosities in the range of 0.8 to 0.84
are normally used.
Since
the PET bottles are lighter, a truck can carry 60% more of the beverage and 80%
less packaging–a fuel saving of 40% and less air pollution.
•
Wine (Fruit/Sap based): Wine is a beverage resulting from the fermentation by
yeasts of the juice of grapes with appropriate processing and additions. The
major deteriorative reaction in wines is caused by oxidation, the oxygen gradually
changing the wine character, leading to development of browning and undesirable
flavours. The most common form of packaging used for wines is the glass bottle
sealed with natural cork. Since wines are affected by sunlight, the bottles
usually used are of coloured glass. Bottled wine is normally stored in the
horizontal position so that the cork is kept moist, thereby providing a better
barrier to the ingress of oxygen. The most significant change in the packaging of
wine resulted from the development of the bag-in-box package: a flexible,
collapsible, fully sealed bag made from one or more plies of synthetic films, a
closure and a tubular spout through which the contents are filled and dispensed,
and a rigid outer box or container. The bag is generally constructed from
co-extruded film of EVA-BA-EVOH-BAEVA or LDPE-BA-EVOH-BA-LDPE. The features of
the bag-in-box system of packaging have been explained earlier in the chapter.
The
physical strength of the bag is of prime importance and must remain intact
throughout distribution and subsequent storage. Under normal circumstances, the
bags are subjected
to
two forms of stress: hydraulic shock (normally caused by sudden acceleration /
deacceleration of the pack) and flex crack. By using polymers, which have high
flex resistance and improving the adhesion between the films, the strength of
the bag can be increased.
One
problem associated with the packaging of wine into bag-in-box system is the
decrease
in
shelf-life as compared to that obtained using traditional glass bottles. This
is due to permeation of oxygen through the valve material of the tap. By
improving the barrier properties of the bag and the design of the tap the
problem can be solved. A special heatsealable membrane is partially attached to
the gland during manufacture of the bag. After
filling
but prior to insertion of the tap, this membrane is fully sealed to the gland
and the
potential
entry path is greatly reduced. As a result the bag is completely sealed and is totally
independent of the tap until the membrane is broached when the pack is just
opened
by
the consumer.
Wines
are also available in PET bottles and in stand-up pouches of metallised
polyester laminates.
Distilled
Alcoholic Beverages:
•
Brandy and Whisky: These drinks are obtained by distillation of alcohol
containing drinks. During distillation the aqueous part is separated from the
alcohol. The distillates obtained are sold under several names like brandy, gin,
whisky cognac, vodka, etc and have different alcohol percentage. Because of
their high alcohol percentages, these liquors are mostly packed in glass
bottles so that they can be kept for an infinite time after opening. The
bottles are sealed to prevent alcohol from evaporating and to protect the
contents of the bottles from dirt and dust.
Packaging system for fruits and
vegetables:
Fruits:
Oranges:
Oranges
are placed in moulded pulp trays with cavities for individual oranges. Each
tray contains about 20/25/30 oranges depending upon the size. Four to five such
trays are placed in a corrugated fibreboard box.
Custard
Apples:
Custard
apples are packed in 3-Ply CFB boxes of RSC type or EPS (Expanded Polystyrene)
boxes. The capacity of the box is 3kg. The fruits are placed in one layer
inside the box and depending upon the size the number of fruits vary. The box is closed by application of pressure
sensitive tape.
Lychee:
Lychees
are graded, weighed and packed in plastic punnets of 250 grams capacity. 8 nos.
of punnets are placed in a CFB box (One piece tray type) with ventilation
holes. The capacity of the box is about 4kgs. Lychees are also packed in 3-Ply
CFB boxes of RSC type of capacity 2 kg. These boxes are then put in cold
storage till dispatch. From cold store to airport, the lychee boxes are transported
in refrigerated van. For export the transportation is by air.
Vegetables:
Vegetables
like green chillies, brinjal, papadi, kantola, tindola, bottle gourd are packed
in 3-Ply or 5-Ply CFB boxes with ventilation holes depending upon the capacity.
The capacity of box varies from 5kg to 7kg to 10 kg. Generally the box is
lidded type (0306) but at times for some vegetables RSC (0201) box is also
used. In case of green chillies the different varieties exported are G-4, Kiran
and Jawla, while the different varieties of brinjal exported are black beauty,
pink rawaya. In case of bottle gourds, they are wrapped in tissue paper and
then placed in the CFB box. Tindola are also packed in woven sacks of the
capacity of 5 kg to 7 kg.
Vegetables
like arbi are packed in capacity of 5kg and yam are packed in capacity of
10kg to 15kg in gunny bags.
Curry
leaves are packed in plastic pouches of 30gm capacity with ventilation holes
and then placed in 3-Ply CFB box. The capacity of the box is 3kg. In some cases
loose curry leaves are packed in the same box. All the above vegetables are
exported by air.
The
different varieties of potatoes exported are Kuffri Bahar, Kuffri Locker and
Kuffri Badshah. The potatoes are packed in Hessian bags (Jute bags) of the
capacity of 25 kg. The bags used are generally hand stitched and the final
stitching is done in such a manner that there is no space and scope for the
movement of the product within the pack. Two corners of the open end of the bag
when stitched are used as handles while loading and unloading. The potatoes are exported by sea
as containerized cargo in both general purpose as well as refer containers. For
vegetables like brocolli, celery, Brussels sprout and cherry tomatoes, since
the export is negligible, the current packages were not available.
Development
of Packages Based on International Standards:
Consumer/bulk
packages were developed based on International Standards, making reference to:
1.
Manual on the packaging of fresh fruits and vegetables by International Trade
Centre, UNCTAD/GATT (1988 edition)
2.
Guide to food transport-fruits and vegetables. (Mercentla Publication 1989)
Recommendations
are based on UN/ECE and OECD Standards, which are covered in the above
publications.
While
selecting the packaging materials and packages new type of packaging materials
with ability to add value to the product and which is eco- friendly and
economic were considered. Some of these are PET punnets with lid, EPS tray
stretch wrapped, leno/raschel/net bags and moulded EPS box with lid.
Frozen Foods Packaging:
The
prime purpose of packaging of these frozen foods is to keep food from drying
out and to preserve nutritive value, flavor, texture and color. Labels on
packages will say if the product is suitable for freezer storage.
A
good packaging material should have the following characteristics:
·
Moisture/vapor-proof or at least
moisture resistant.
·
Made of food grade material, i.e.
designed to be used for food products.
·
Durable and leakproof.
·
Doesn’t become brittle and crack at low
temperatures.
·
Resistant to oil, grease or water.
·
Protect foods from off flavors and
odors.
·
Easy to fill and seal.
·
Easy to mark and store.
The
packaging you select will depend on the type of food to be frozen, personal
preference and availability. For satisfactory results, do not freeze fruits and
vegetables in containers larger than one-half gallon. Packaging not
sufficiently moisture/vapor-resistant for long-time freezer storage includes
ordinary waxed paper and paper cartons from ice cream and milk.
Rigid
Containers:
Rigid
containers are made of plastic, glass, aluminum and heavily waxed cardboard and
are suitable for all packs. These are often reusable. Straight or tapered sides
on rigid containers make it much easier to remove frozen foods.
Glass
jars used for freezing should be made for the purpose. Regular glass jars may
not withstand the extremes in temperature. Do not use regular, narrow-mouth
canning jars for freezing foods packed in liquid. Expansion of the liquid could
cause the jar to break at the neck.
Cans,
such as shortening and coffee cans, are good for packaging delicate foods. Line
the can with a food-storage bag and seal the lid with freezer tape because they
are not airtight.
Baking
dishes can be used for freezing, heating and serving. Dishes may be covered
with a heavy aluminum foil taped with freezer tape. To reuse the baking dish after
the food is frozen, wrap the food in casserole- wrap fashion.
Ice
cube trays are good for freezing foods in small amounts. Freeze food until firm
and then transfer to freezer bags.
Flexible
Bags or Wrapping:
Bags
and sheets of moisture/vapor-resistant materials and heavy-duty foil are
suitable for dry packed vegetables and fruits, meat, fish or poultry. Bags can
also be used for liquid packs. Protective cardboard cartons may be used to
protect bags and sheets from tearing and to make stacking easier. Laminated
papers made of various combinations of paper, metal foil and/or cellophane are
suitable for dry packed vegetables and fruits, meats, fish and poultry. Laminated
papers are also used as protective overwrap.
Packaging,
Sealing and Labeling:
·
Cool all foods and syrup before packing.
This speeds up freezing and helps retain natural color, flavor and texture of
food.
·
Pack foods in quantities that will be
used at one time.
·
Most foods require head space between
the packed food and the closure for expansion as the food freezes. Loose
packing vegetables, such as asparagus and broccoli, bony pieces of meat,
tray-packed foods and breads, do not need head space.
·
Pack foods tightly to cut down on the
amount of air in the package.
·
Run a nonmetal utensil, such as a rubber
scraper handle, around the inside of the container to eliminate air pockets.
·
When wrapping food, press out as much
air as possible and mold the wrapping as close to the food as possible.
·
When packing food in bags, press the air
from the bags. Beginning at the bottom of the bag, press firmly moving toward
the top of the bag to prevent air from re-entering or force the air out by
placing the filled bag in a bowl of cold water taking care that no water enters
the bag. Seal either method by twisting and folding back the top of the bag and
securing with string, good quality rubber band, strip of coated wire or other
sealing device. Many bags may be heat sealed, and some have a tongue-in-groove
seal built in.
·
Keep sealing edges free from moisture or
food so they will make a good closure.
·
When using tape, it should be freezer
tape, designed for use in the freezer. The adhesive remains effective at low
temperature.
·
Label each package with name of product,
date, amount and any added ingredients. Use freezer tape, freezer marking pens
or crayons, or gummed labels made especially for freezer use.
Packaging of dried or de-hydrated foods:
Dried
foods are susceptible to insect contamination and moisture reabsorption and
must be properly packaged and stored immediately First, cool completely. Warm
food causes sweating which could provide enough moisture for mold to grow. Pack
foods into clean, dry insect-proof containers as tightly as possible without
crushing.
Glass
jars, metal cans or boxes with tight fitted lids or moisture-vapor resistant
freezer cartons make good containers for storing dried foods. Heavy-duty plastic
bags are acceptable, but are not insect and rodent proof. Plastic bags with a
3/8-inch seal are best to keep out moisture. Pack food in amounts that will be
used in a recipe. Every time a package is re-opened, the food is exposed to air
and moisture that lower the quality of the food.
Fruit
that has been sulfured should not touch metal. Place the fruit in a plastic bag
before storing it in a metal can. Sulfur fumes will react with the metal and
cause color changes in the fruit.
