Refrigerated storage of perishable foods

Refrigerating products

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This table displays the storage life of some chilled food in the coldest part of a refrigerator:

Food

Expected shelf life in the home

Seafood

3 days

Crustaceans and molluscs

2 days

Meat

3-5 days

Minced meat and offal

2-3 days

Cured meat

2-3 weeks

Poultry

3 days

Fruit juices

7-14 days

Milk

5-7 days

Cream

5 days

Cheese

variable (1-3 months)

Soft cheeses (camembert, brie)

2-3 weeks

Cottage, ricotta, cream cheeses

10 days

Eggs

3-6 weeks

Butter

8 weeks

Margarine

variable (6 months)

Oil and fat

variable (6 months)

N.B. Many of these products are labelled with a 'use-by' date. This can be used as a guide to shelf life of the unopened product.

Below are tips on how to store different types of food.

Dairy products

Fresh milk, cream and some soft cheeses have only a short shelf life and lose quality rapidly if exposed to warm temperatures during storage. If you find you cannot store these products satisfactorily up to the 'best before' date, check your refrigerator temperature.

If your refrigerator temperature is below 5 °C, check how you handle the product. Does it stand around at room temperature? Do people drink directly from the carton? Do you pour milk back into the carton from a milk jug?

Fresh milk, cream and some soft cheeses have a short shelf life and lose quality rapidly if exposed to warm temperatures during storage.

If you still have problems, watch how your supplier handles the product. If you suspect temperature abuse, change your supplier. Dairy products tend to pick up flavours from other foods, so keep them wrapped or covered and away from strong smelling foods.

Hard cheeses have a long storage life but may develop surface mould. If this occurs, remove the mould and about 2cm of cheese around it. Reduced salt cheeses may have a shorter shelf life than regular cheeses.

Eggs

Eggs, contrary to what many people believe, should be stored in the refrigerator. This will maintain egg quality and considerably lengthen storage life. They should preferably be stored in their cartons to reduce moisture loss through the shell.

The storage life which can be expected for eggs in the shell is determined very much by the storage temperatures during distribution. Most stores do not keep eggs under refrigeration and, depending how long the eggs have been stored at room temperature, the potential shelf life will be affected.

Raw meat, poultry and seafoods

The term 'meat' includes beef, lamb, pork, etc. These items should be stored in the coldest part of your refrigerator.

Wrapped fresh meat can be kept safely for up to three days and unwrapped fresh meat up to five days at cold temperatures, 0° to 3° C. Wrapped meat remains moist and maintains its quality but surface growth of microorganisms is encouraged and the meat becomes slimy after about three days. If you notice an off odour, the best thing to do is to throw the food out.

Unwrapped meat lasts longer than wrapped meat. When meat is stored unwrapped, the exposed surface dries out. This drying retards microbial growth but over-drying causes undesirable colour changes and loss of flavour.

A compromise can be reached by storing your meat in an adequately ventilated container or loosening the wrapping around the meat so air can circulate. To ensure all surfaces are exposed to drying, place the meat on a clean stainless steel, chrome plated or plastic rack. Do not sit the meat on a plate or other solid surface, or pack it too closely. This will reduce the drying effect. Cured meat has a longer storage life. Unwrapped cured meat may last up to three weeks at 0° to 3° C.

Uncooked minced meat, liver, kidneys, poultry and seafoods need careful storage because they usually carry large numbers of spoilage microorganisms.

Uncooked minced meat, liver, kidneys, poultry and seafoods need careful storage because they usually carry large numbers of spoilage microorganisms. These can grow even at refrigeration temperatures, so always store these foods in the coldest part of the refrigeration section as close as possible to 0° C. The longest recommended storage time is three days.

Before storing chilled chicken for a couple of days, it is a good idea to take off the plastic wrapping, wash the chicken thoroughly, dry it with a paper towel then store as above. Fresh whole fish should be gutted and washed if it is to be stored for more than 24 hours.

Meat designated as 'pet food' should not come into direct contact with meat for human consumption as it may have been produced under less hygienic conditions. It should be well wrapped and stored in the coldest part of the refrigerator.

Cooked meat, poultry and seafoods

Meat, poultry and seafoods must be refrigerated as soon as possible after cooking. Do not leave them on the bench top to cool before placing them in the refrigerator. The warmth of the food will encourage growth of any microbes which may get onto the meat from your hands, utensils etc. This is especially important with casserole-type dishes where food poisoning bacteria can actually survive the cooking process.

Modern refrigerators can cope with small amounts of hot foods being placed directly into them. However, to avoid excessive condensation in the refrigerator, a brief cooling period (not more than one hour) prior to refrigeration is preferred. You may wish to use a timer to remind you when the time is up.

To avoid condensation, do not cover hot meat pieces before refrigerating. Place them uncovered in the refrigerator until they are cool, then cover the container or wrap the meat tightly with cling wrap. Store cooked products above any raw meat, poultry or seafoods to avoid cross contamination from raw meat liquid or drip where this could occur. However, if the top shelves of your refrigerator are the coldest, the more perishable fresh meats should be stored there. Special care should then be taken to cover other dishes to prevent contamination.

Meat, poultry and seafoods must be refrigerated as soon as possible after cooking to retain freshness.

Large amounts of food should always be divided into smaller containers before cooling. It can take many hours for the centre of a large container to cool to a temperature which will stop the growth of food poisoning bacteria. If you do not expect to eat the food within three or four days, it is best frozen immediately.

Delicatessen meats

Most delicatessen meats such as ham, corned beef, polish salami, and other luncheon meats must be stored in the fridge. They should be treated like fresh meat but they should not come into contact with fresh meat. Pâtés also fall into this group.

Some of the fermented salamis, bacon and whole hams will keep for 2-3 weeks compared to sliced luncheon meats which will keep only 4-5 days after purchase. When purchasing unpackaged pre-sliced luncheon meats, examine the products on display carefully. If there is any slime or excessive moisture, ask for slices to be freshly cut from the knob. It is a good idea to buy only small quantities of sliced luncheon meats.

Pre-packaged delicatessen items can be stored until the 'best before' date. These are often vacuum packaged and have a longer shelf life. But do buy carefully - avoiding damaged or blown packages. A slight sour smell may be noticeable as the product starts to lose quality.

There are now a series of fermented salami knobs sold which are wrapped in plastic over the casing. Make sure you read the storage instructions carefully. While the unwrapped type could be stored outside the refrigerator, these wrapped versions usually require refrigeration after the casing has been broken.

Fresh fruit and vegetables

Fruit and vegetables should be handled carefully to avoid bruising and breaking the skin. Such damage will encourage deterioration and rotting.

Most fresh produce is temperature sensitive and should be stored in the coolest part of the house when refrigerated space is not available. Some produce, particularly those from the tropics, such as pineapple and bananas, are chill sensitive and should not be stored in the refrigerator.

To reduce shrivelling or wilting due to water loss, keep leafy and root vegetables, such as silverbeet, broccoli, carrots and parsnips, in perforated plastic bags, preferably in the refrigerator.

By removing leafy tops from carrots, parsnips, turnips and beetroot, their storage life can be extended to many weeks or even several months in the refrigerator. Keep potatoes in a cool, dark, well ventilated place to avoid greening and sprouting; remove from plastic bags and place in a strong paper bag, box or in a wire or plastic bin. Sweet potatoes are cold sensitive and should not be kept in the fridge.

Cool apples, pears, stone fruits and strawberries on the refrigerator shelves, and then place into perforated plastic bags in the refrigerator. This reduces sweating (water forming inside the bag). During spring and summer the shelf life of apples at room temperature is only short. If possible remove them from refrigeration just before eating.

Keep nectarines, peaches and plums in the refrigerator, unless you want to ripen them. Pears are best kept in the refrigerator. They keep well green and hard. Store at room temperature to ripen them. Citrus fruits, cucumbers, passionfruit, capsicums and eggplant lose water easily during refrigerated storage. Waxing or wrapping in shrinkwrap helps reduce water loss.

Different varieties of a fruit often have better keeping qualities than others at a given storage temperature. For example, Fuerte avocados will not keep beyond about three weeks in the refrigerator, whereas other varieties, such as Hass, will keep up to six weeks. Also, some varieties of apples (e.g. Granny Smith and Fuji) have more than three times the storage life of others.

Tomatoes should be ripened at room temperature, away from direct sunlight. They ripen best in mildly warm temperatures. When fully ripe, especially in hot weather, they may be stored in the refrigerator for several days. However, they will gradually lose flavour and some soft areas may develop in the flesh.

Different varieties of a fruit often have better keeping qualities than others at a given storage temperature.

Rockmelon, pineapple, paw paw, bananas, mangoes, avocados, stone fruit, tomatoes and pears need to be ripened at room temperatures. They can then be refrigerated for a short time. Fruit ripening can be accelerated by keeping unripe fruit with passionfruit and ripe apples.

To reduce mould growth in onions, whole pumpkin, marrows and squashes, store at room temperature under dry conditions, in a net or loose.

If storing large amounts of fruit, remove overripe and injured fruit regularly as these will trigger ripening and subsequent aging in the remaining fruit. Also remove any rotting fruit as infection can spread to other fruit.

The longer keeping kinds of produce can be stored for shorter periods at temperatures higher than the optimum listed in the table. Generally, however, the life of a commodity is reduced rapidly at temperatures above the optimum.