Packaging and Storage of Milk

productsSharon A J

15-MVM-044Technology of Milk products

Necessity of Food Packaging

oProtect from outside influences and damage

o Maintains food safety & extend shelf-life

o Minimizes environmental impact

oEasy handling & transportationo Boost sales in a competitive

environment o Provide consumers with

ingredient & nutritional information

Packaging types

• Primary packaging (Consumer package)

• Secondary packaging (Distribution package)

• Tertiary packaging (Shipping container

Symbols used on Plastic packages

Factors Involved In Selecting A Package:

• Type of Milk product and its consequent resistance to mechanical damage

• Presence of specific flora• Wholesale or retail packaging• Permeability to water vapour, oxygen, CO2, NH3, and light• Labelling facilities• Migration of flavour from package to product.• The system for storage, distribution and sale.

Packaging of milk products

• Milk is highly perishable and liquid in nature

• Requires a container at every stage of movement • Development of containers suitable for various stages of

of marketing and distribution due to their increased demand

Cans

• Metal cans, provided with a lid and having capacities up to about 80 litres.

• 40 litres cans are more desirable. • Type of container facilitated the transport of milk to long

distance hence helped in growth of the dairy industry.

Aluminium alloy milk can Plastic Milk cans

Importance of Storage, Packaging

• Storage requirements vary widely – from a few hours to several days.

• Must take into account the marketing system• The compatibility of products kept together• The Entrepreneur’s individual needs.

STORAGE is to..

• Prevent physical and quality losses in the harvest products.

• Smooth out supply and demand peaks in the producer-to-consumer marketing chain over a period of time.

• Storage helps to prevent deterioration of the products.

Bulk chiller for milk storage

General rule in storing

• Only one type of products should be stored in each storage area, in order to optimize the specific storage conditions for that particular products.

• Using the same storage area for different products can result in product damage because of incompatibility of temperature and relative humidity conditions, chilling, odour contamination and other problems affecting shelf life and quality.

Characteristics of Packaging Systems

• RETURNABLE CONTAINERS: • The basic features of systems using returnable containers are

the collection of empties and washing prior to re-filling. • Differences in operation times and capacities of the various

machines involved make intermediate storage necessary.• Storage of washed cans is permissible as they have lids but

storage of washed bottles is extremely bad practice because they are unsealed and therefore liable to contamination.

Returnable container

Glass bottles• The New York Dairy Company is

credited with having the first factory that produced milk bottles, and one of the first patents for a milk container was held by the Lester Milk Jar.

• PASTEURIZED MILK IN BOTTLES. Bottles with wide necks (36 to 40 mm), suitable for sealing with aluminium foil caps made in situ from reeled strip, form the most common system for packaging of pasteurized milk in returnable containers.

• PASTEURIZED MILK IN CANS: The aluminium milk can has proved very satisfactory in service and, since the beginning of the second half of this century, has rapidly replaced the previously-used tinned mild steel can.

SINGLE SERVICE CONTAINERS

• Common feature• After emptying they are discarded. • There is no collection and washing of the milk packages - only

crates are collected and washed.• Intermediate storage of packing material and filled packages is

required and this must be provided in the plant

Pasteurized milk in cartons

• Tetrahedral cartons made from polyethylene laminated paper board and packed in hexagonal plastic crates have been chosen as the ideal system of pasteurized milk packaging.

Material used

• The material used in each case is polyethylene-coated paper-board

• In aseptic versions an aluminium foil lamina is normally incorporated.

• Pre-formed cartons or pre-cut, single-piece blanks pre-creased ready for forming into a container must be used for the container with a gable top

Forming of a milk carton

PASTEURIZED MILK IN SACHET

• Pillow-shaped sachets with a longitudinal seam made from reeled low-density polyethylene film have been chosen as the ideal packaging materials.

• . They may be reeled single or double film or lay-flat tube, the latter avoiding the necessity of making the longitudinal seam in the packaging machine. The material should be coloured to reduce light transmission.

• The film is shaped and welded into a tube. The tube is filled with pasteurized milk with the help of a balance tank, where the level is kept constant by means of a float.

• The transverse seals are generally made above milk level. • The packages are separated by guillotine and placed in

rectangular plastic crates holding 20 packages each and the crates are then palletized

FORM FILL SEAL SYSTEM

Packaging of Cream

• Cream is packaged for retail sale in units similar to those for milk, such as a glass bottle, paper cartoon coated with water proof layer of either PE or wax, LDPE sachet, plastic bottles etc.

• Cream is stored preferably at 5-100C, and distributed as early as possible, preferably within 3 hours of removing it from cold storage

BUTTER• Packaging: Packaging starts after removing

butter from churn done either manually, by gravity or by mechanical means.

• TYPES OF PACKS:• (i) Bulk or wholesale: in boxes, tubs, casks. • (ii) Retail: 25gm, 100gm, 250gm, or 500gm. • Also in collapsible (metal) tubes.

PACKAGING MATERIALS USED:

• Wood or timber: White Ash or Spruce, White pine, firkin, teakwood

• Parchment paper / substitutes: Vegetable parchment paper, butter paper, cellophane, pliofilm, Poly Ethylene.

• Aluminium foil/laminates: Moisture and greaseproof, non-tainting and non-toxic, opaque, air-tight in nature. Embossed aluminium foil

• Tin-plate cans: Advantageous in tropical countries not only in preventing melted butter from escaping in hot weather but also prevents absorption of foreign flavours.

Wooden package Butter paper Polyethylene package

Tin plated tubsPlastic tubs

TECHNIQUE OF PACKAGING;

• • Hand moulding and wrapping• • Mechanical wrapping, patting and wrapping.

Butter churner

STORAGE• Cold storage temperature range from-230C to -290C. • Butter should be stored in dark room as exposure to

light lowers keeping quality.• The temperature during the period of distribution of

butter should be preferably -180C.• And should be sold in retail trade from a deep

freeze/refrigerated butter box.

BUTTER OIL• PACKAGING

• Packing butter oil extreme care should be taken to exclude oxygen. • It is important to avoid re-aeration of the products as it comes out of the

vacuum dehydrator in a partially or a completely de-aerated form.• Replace the head space with inert gas.• Upon filling, the fat should run into the bottom of the container in such a

way as to avoid contact with the air.• Tin cans are satisfactory for both bulk and retail packaging, wooden

casks and tubs with suitable liners, waxed or plastic-coated can also be used.

STORAGE• Under atmospheric conditions, butter oil develops a

perceptible oxidized flavour in a course of a months.

• Use of antioxidant Ethyl gallate in a concentration of 0.005% increase the shelf life to 3 months.

• Alternatively packing the products in a 1 kg container under 50 cm Hg vacuum prior to sealing ensures satisfactory storage quality.

CHEESE• Factors involved in selecting a package:

• Type of cheese and its consequent resistance to mechanical damage• Presence of specific flora• Wholesale or retail packaging• Permeability to water vapour, oxygen, CO2, NH3, and light• Labelling facilities• Migration of flavour from package to product, and • The system for storage, distribution and sale.

Packaging: Packaging is an important aspect of the curing of cheese.

Cheese processing before packing

• Often cheese is treated with paraffin wax (early days)• Now most of them are coated with a latex• Before waxing its surface should be very clean and dry;

otherwise growth of bacteria between cheese rind and paraffin wax or latex coating will cause problems, especially because of gas production and off-flavour.

• Some cheese are cured while being packaged in an air and water vapour tight shrinkage film, e.g. Saran foil,

Rind

• Rinds, -The outside layer that form on a cheese during the cheese making and aging process.

• Most rinds (except for wax, cloth or bark are naturally edible and will enhance a cheese's overall flavour

Storage of Cheese• The storage of cheese starts after its manufacture. Often, this is after the salting.

• Storing Soft Cheese

• Soft, semi-soft or semi-hard cheese wrapped in in waxed or parchment paper.

• The paper allows the cheese to “breathe” meaning that the cheese is protected, but a little bit of air can still filter through the paper.

• Soft cheese needs exposure to air so it does not become too moist and watery.

• Wrapping in plastic wrap smothers the cheese, trapping moisture that will destroy the rind and the flavour of the cheese

Soft Cheese

Storing Hard Cheese

• Storing hard cheese, trapping moisture is of less concern.• Hard cheese will dry out too much in the refrigerator. • It should be protected from the air by being placed in a

sealed plastic bag or sealed (glass or plastic) container.• Hard cheese can also be wrapped in plastic wrap.

Cheese storage

Plastic packaging in hard cheese

CONDENSED MILK

• Condensed milk are those products obtained by evaporating parts of the water of whole milk, or fully or partly skimmed milk, with or without addition of sugar

Packaging of condensed milk

Packaging• Bulk packaging may be done in barrels• Drum with PE liners• Tin containers.• Packing in can • The packing section is supplied with air purified through bacterial

filters. In this section, rigorous hygienic standard are paramount.

Storage of condensed milk

• Main consideration in storage is the temperature of storage to prevent defects such as

• Sandiness • Sugar separation • Viscosity changes.

• During storage a wide temperature variation may increase the tendency to sandiness.

• A very low storage temperature such as 00C or below may not only cause sandiness but also sugar separation.

• Cool storage is important to prevent in viscosity. • Condensed milk products should be stored at 10oC or

below, and humidity of the room should be 50% or below to check spoilage of cans and labels

MILK POWDER

• Powdered milk or dried milk is a products obtained by the removal of water from milk by heat or other suitable means, to produce a solid containing 5% or less moisture.

• It has a far longer shelf life than liquid milk and does not need to be refrigerated.

PACKAGING• Improved tin can are proving to be economical effective

medium.• Paper sack with four layer of paper and inner layer of PE are

most commonly used.• Gas packing is most commercial procedure for increasing shelf

life of milk powder.• Oxygen content is reduced to 2% or less in the head space gas.

Then the product is vacuum packed with the low oxygen level, however replacing the oxygen with nitrogen is more common in dry milk industry.

STORAGE• Dry milk products are most sensitive to environmental conditions particularly to

temperature and moisture content. • Vitamins A and D are photosensitive and will break down rapidly if exposed to light. • The area where dry milk is stored should be kept as cool as possible. • Air-conditioning or even refrigeration can greatly extend the nutrient shelf life.• Container should be opaque to light or milk powder stored in a dark room.• Dry milk will absorb moisture and odours from the air• Storage containers should be impervious to both air and moisture. • The use of desiccants improve shelf life.• Powdered milk canned with nitrogen or carbon dioxide to replace air gives

improved shelf life• . Vacuum canning also helps increase the shelf life.

GHEE• Packaging• Tin container are mostly used as they are impervious to the action of

light and air. • The tin container should be new and free from any trace of rust. • preferably a minimum tin coating weight corresponding to 50 ETP

(Electrolytic Tin Plate). • Cheaper plastic container are also being used.• Storage: The development of an oxidised flavour or tallowiness in

ghee is accelerated at higher storage temperature. Refrigerated storage delays acid development and thereby prolong keeping quality.

Glass bottle cans Plastic tubs and bottles

ICE-CREAM

• Storage: Product should be kept cold with minimal temperature fluctuations throughout the cold chain, from factory cold store to retailer's cold store to store freezer, in order to prevent a decrease in product quality due to ice recrystallization and coarsening (which gives the ice cream a grainy texture). A core temperature lower than - 18°C is being regarded as the good practice reference for consumer units.