Press Release (ePRNews.com) - MALMö, Sweden - Aug 30, 2016 - After all, this is a sign of progress and it’s also reassuring to know that no matter what the season, you can find precisely the IQF fruit you desire. Customers demand the highest quality for IQF fruit, depending on the intended use of the product. For example, if the IQF fruit is intended to be consumed without any further processing after thawing, then the quality of the texture is more important, compared to its use as a raw material in other industries.
If conventional methods of freezing are used for fruits, they might destroy the turgidity of living cells in the fruit tissue. Unlike vegetables, fruits don’t have a fibrous structure that can protect them against this destructive effect. Furthermore, fruits to be frozen are harvested at the moment when they are fully ripened and their structure is extremely fragile. Additionally, fruits have gentle flavors that can be easily damaged or altered by fluctuating temperatures. Another challenge is to preserve the natural color of the IQF fruits. Therefore, adequate processing is essential for all steps involved in the freezing process, from harvesting to packaging.
The appropriate harvesting time
The characteristics of raw products are essential in determining the quality of the IQF fruit: the genetic makeup, climate of the growing area, type of fertilization, and maturity of harvest.
The use of mechanical harvesting is not recommended since it generally causes the bruising of fruits and results in a wide range of maturity levels for fruits. On the other hand, hand-picking provides gentler handling and maturity sorting of fruits. Unfortunately, hand-picking is non-economical in comparison with mechanical harvesting, due to the high labor cost.
Generally, harvesting fruits at the best level for commercial use is difficult. In order to determine whether a fruit has reached optimal maturity for harvest, pressure tests are applied to fruits. The color is another characteristic used to determine maturity since an increased level of maturation causes a darker color in fruits. The best way to assess the level of maturity for harvesting is to use a combination of color and pressure tests.
Prior to freezing, some fruits are placed in a controlled atmosphere storage. A controlled atmosphere is high in carbon dioxide and low in oxygen content and it slows down the rate of respiration, which may extend the shelf life of any respiring fruit during storage. But these fruits do not ripen substantially after picking, since most of them are picked as near to eating-ripe maturity as possible, in order to achieve remarkable IQF fruit.
The quality level of the raw materials prior to freezing is the major condition to obtain outstanding IQF fruit. It is recommended that fruits are prepared prior to the freezing process in terms of peeling, slicing or cutting.
In the case of fruits that require peeling before consumption, peeling is done by scalding the fruit in hot water, steam or hot lye solutions. You must take into consideration the effect of peeling on the quality of IQF fruit. The level of freezing can be increased by decreasing the size of products frozen, especially in the case of large fruits. As a consequence, an increase in the freezing level results in smaller ice crystals, which decreases cellular damage in fruit tissue. Banana, mango, and kiwi are some examples of large fruits commonly cut into smaller cubes or slices prior to freezing.
Some fruits require blanching before freezing. Blanching is used to inactivate the enzymes which cause changes in color, odor, flavor, and nutritive value. Since heat treatment causes losses of such characteristics in fruits, only a few types of fruits are blanched for inactivation of enzymes prior to freezing. The loss of water-soluble minerals and vitamins during blanching should be minimized by keeping blanching time and temperature at an optimal combination.
Now the fruits are ready to enter the IQF tunnel freezer and to become remarkable IQF fruits, with a natural appearance, size, color, and shape.
For more information, visit http://www.octofrost.com/berries.