Generalities
What are climacteric fruits and what are the non
climacteric fruits?
Climacteric fruits are those that once picked go on ripening, that is to say they are harvested before their maturity. The point at which fruits are ready to be harvested is called Physiological Maturity, and when they taste good for consumption it is called Maturity for Consumption - Commercial Maturity. Apple, pear, banana, kiwi, mango and papaya are among these. On the other hand, the non-climacteric fruits are those which, after being picked, do not show significant changes in maturity, and among these are plums, peaches, nectarines, cherries, grapes, and pineapple.
What is controlled atmosphere?
If we want to store fruit for a long period of time we have to delay even longer the fruit respiration process, since in conventional cooling the maturity process is very slow but it still moves on. That is why Controlled Atmosphere was developed: it consists in lowering the oxygen in the air so that the respiratory rate of the fruit is delayed and the ripening process is blocked. In this way the fruit is of the same organoleptic quality as at the moment of introducing it in this kind of cameras.
How are climacteric fruits ripened after harvesting?
To consume fruit that has already reached physiological maturity but not its characteristic flavour, it must go through a process opposite to that for its conservation. If we remove them from the cold, most fruits ripen after a few days at ambient temperature, if possible with high atmospheric humidity to avoid dehydration.
Are non climacteric fruits consumed just as they are harvested?
The non-climacteric fruits show slight changes in their organoleptic appearance. A yellowish background colour and a slight softening are two parameters that make the product is tempting to our senses. If the fruit is consumed before it reaches its optimum point, we will have more acid flavours, greater astringency, less juice, less sugar and greater consistency. As with climacteric fruits, after exposure to ambient temperatures for two or three days they will obtain their characteristic flavour (provided physiological maturity is adequate). It must be remembered that low relative humidity can dehydrate the fruit.
Why shouldn't uncooked food (for example meat) be stored next to fresh fruits?
Raw food may contain microorganisms that can be made innocuous through a cooking process. Fresh products will not undergo any other process in which a contaminant may be removed, which is why they shouldn't be placed next to uncooked food.
What takes place in relation to cleaning products or other products with strong scent (ex. coffee)...?
Products with strong scent should never be next to fruits since the fruit could take on the scent or taste and thus spoil its characteristic attributes.
How can the maturity process be accellerated to obtain consumption maturity?
The fruit must be placed in a paper or carton bag (never in a polly bag) firmly closed and at ambient temperature. Beside these fruits we can place a few apples to produce a good quantity of the hormone Ethylene that accelerates the maturity of many fruits. NO FROST fridges dehydrate fruit, which is why it should be placed in other areas in the refrigerator that keep humidity levels.
What about the bruises the fruit receives?
Bruises in fruit generate two problems: on the one side the softening and subsequent degradation of the affected area (it grows blackish); and at a later stage that area can be attacked by mircoorganisms.
Why are there sandy apples?
When the fruit ripens, some changes are produced in its composition. When its ageing stage draws near various components get degraded causing the apple to show a sandy texture, totally different from its characteristic one. That is to say, "sandy" is synonymous with "ageing".
|
