increase vegetable digestibility. Although cooking at lower temperatures may preserve better the
colours of vegetables and cell damage, high temperatures mean shorter cooking times which mean
reduced nutrient loss and reduced chances for the vegetables to lose their natural colours. However,
vegetables should not be overcooked or the desired volatile components may evaporate or break
down and the texture will become too soft. Vegetables should be removed from the cooking water just
before they have reached the desired texture, because they will continue to cook slightly after being
removed from the cooking water due to the residual heat contained in the vegetables.
The special case of fruits
Fruits are very similar to vegetables in their structure and content, except they have a much higher
During ripening, the starch stores in fruits are slowly broken down into sugar, and the acid levels
slowly decline. Therefore a ripe plum will taste much sweeter than its relatively acidic under ripe
As ripening continues, the fruit will start to produce ethylene, which further accelerates the ripening
process. The rate of ripening of, for example bananas or tomatoes, can be placed in a well aerated
environment, so that the ethylene produced does not make the fruit go off. Equally, to ripen fruits more
rapidly, they are often kept in a closed un-aired drawer.
For similar reasons to when freezing vegetables, freezing fruits make them lose their original
crispness, and the defrosted fruit will be much softer than a raw equivalent. It is therefore sometimes
recommended that raw frozen fruits should be eaten before they have completely thawed.
Like for vegetables, the more rapid the freezing, the less resulting texture damage in the thawed
Unlike vegetables, fruits should not be rapidly blanched before they are frozen to kill the enzymes
responsible for spoiling because the combination of the detrimental effects on taste and texture by
blanching and freezing is not really acceptable for a product that is usually eaten raw, as most fruits