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SPECIAL FOCUS



                  generally provides better quality of food   For this reason, frozen food manufacturers
                  than slow thawing. Because the       should provide instructions or educate
                  temperature of frozen food is slightly lower   consumers how to defrost safely or to cook
                  than the freezing point (subfreezing   appropriately, for example, to thaw only
                  temperature), it causes some negative   the amount of food required for
                  effects as belowed;                  cooking. Might as well give an
                     - Recrystallization creates larger ice   advice or warning of what if the
                  crystal that can damage the structure,   thawed food cannot use up for
                  membrane  tissues,  and  texture  of  the   the safety of the consumers and
                  food.                                reputation of your factory.
                     - Chemical reaction that flows at a very
                  high-speed causes undesirable effects on
                  color, odor, flavor and nutritional value of   เอกสารอ้างอิง/Reference
                                                       http://library.uru.ac.th
                  foods, resulting in adaptation and growth
                  of some microorganisms, especially if it
                  takes long time to defrost.
                     Even so, if the frozen food operator
                  can handle an effective quality and
                  sanitary  control  during  the  production
                  process, it’s less potential to have severe
                  problems of the growth of the pathogenic
                  microorganism from regular thawing
                  process (following the instruction provided
                  by the factory to consumers). The key is
                  that the factory must control the amount
                  of microorganism in the food (load of
                  microorganism) abreast standards. During
                  defrosting, the food should not get direct
                  exposure by the thermal conductivity, such
                  like water serves as a coolant. This is often
                  the source  of  microorganism
                  contamination. On the other hand, packed
                  the frozen food with a film or skin-tight
                  packaging and soaking it in circulating
                  clean water is the quickest way to thaw
                  the frozen foods.

                  Is it Safe to Refreeze Thawed
                  Foods?
                  Putting a thawed piece of frozen food back
                  into the freezer or reprocess might lead
                  to a decrease in the food quality. That is
                  equal to freeze low quality food which is
                  contrary to the principle of good freezing
                  practice. There may also be defects in the
                  tissue structure and partially lose some
                  nutritional value before re-freeze.
                  Generally speaking, the freeze-thaw cycle
                  definitely triggers the reduced quality of
                  food, more or less depending on the type
                  of food, freezing techniques, as well as
                  storage (time and temperature), thawing
                  and cooking practices. But the most
                  important to be taken into consideration
                  is the microbiology safety that a
                  microorganism can grow during the first
                  and after thawing, plus a risk of an
                  increasing microorganism contamination.





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