Shelf life is a integral and important part of any food, with European legislation defining it as the “date of minimum durability”. All food and drinks have a length of time given to them after which they are considered not suitable to be consumed. The term ‘shelf life’ is used to describe this period, when the quality of a piece of food is at its peak and suitable for consumption. It is important because at the end of a products shelf-life, it begins to develop characteristics that make it unacceptable, undesirable and unsafe to eat. That is not to say that a item that has gone past its shelf life is no longer safe to eat, but its quality cannot be taken for granted.
Food labelling with date marking came into prominence because of the rapid changes occurring in food manufacturing, packaging and retailing. It is a very clear way of notifying consumers about the state of a food item and of also prohibiting retailers from selling packaged food stuff after the expiration of the use-by date.
The actual shelf life or use by date of any foods is usually displayed on the labelling of a food item, and must be in a date format that can be easily understood by a consumer. Remember they are there for a reason, to keep what you eat safe and enjoyable, whilst at the same time reducing food costs and helping to cut down on waste. In conclusion foodstuffs with a ‘use-by’ date should not be offered for sale after this date, due to the real possibility that it has deteriorated to a stage where it is unsafe to eat.
Who decides on a use by date
The responsibility of determining the shelf life of a food, and thus its best-before or use-by date, usually lies with the manufacturer or packer. These companies come to a fixed date by conducting storage trials (at the development stage) under realistic, defined conditions. They have a legal responsibility to determine the date of minimum durability, and ensure that the food is safe for that period of time, and to label their food products accordingly. The manufacturers or producers should also provide clear handling instructions for a food item which has been opened.
What can shelf life be affected by
Food stays fresh for a limited time before it goes bad, and can deteriorate for a number of reasons, how fast really depends on its make-up and how it is stored. Below is a list of some of the main reasons for deterioration;
- Exposure to heat.
- Exposure to light.
- Exposure to moisture.
- Exposure to chemicals.
- Exposure to bacteria and microorganisms.
Best before dates
This is the date up until which a food can be expected to reasonably retain its optimum properties like quality and taste. Products in this category can include frozen, canned and dried foods.
Use by date
This relates to foodstuff which is highly perishable and are therefore likely after a short period to become unfit for human consumption. The ‘use-by’ date is the date up to which the food may be used safely i.e. consumed, cooked or processed, once it has been stored correctly. Most fresh, ready-to-eat and chilled foods fall into this category and require a ‘use-by’ date.
Remember that the signs of spoilage are not often obvious. If for some reason you are not sure about the quality of a food, then NEVER taste it. The golden rule is ‘if in doubt throw it out’.
Signs that meat that has gone bad;
- It feels slimy when you touch it.
- It gives off a bad odour.
- Unnatural looking colour.
Signs that canned food has gone bad;
- Bulging tops
- Lost seal
- Product is bubbly
- Product spurts out of jar when opened.
- Scum of thick film on top of it.