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useFul tips FOr vacuum sealing and FOOd saFety
impOrtant:
Vacuum sealing is NO substitute for refrigeration or freezing.
any peri-
shable foods that require refrigeration must still be refrigerated or frozen after vacuum
packaging. as with any other storage method, food must be checked carefully before
storage and, as well, before consumption.
Vacuum packaging extends the shelf life of foods by removing most of the air from
sealed bags and containers, and additionally preventing air and germs from getting into
the sealed packaging, thereby reducing oxidation. Vacuum packaging helps preserve
flavour and overall quality. it also helps inhibit the growth of aerobic microorganisms.
mould –
mould cannot grow in a low oxygen environment; therefore vacuum packa-
ging can stop its growth. However, mould produces spores that will nevertheless be
viable, thus causing new infestation with mould, when oxygen gets into the bag or con-
tainer.
yeast –
results in fermentation, which can be identified by smell and taste. Yeast needs
water, sugar and a moderate temperature to grow. it can survive with or without air.
slowing the growth of yeast requires refrigeration, while freezing stops it completely.
Bacteria –
in most cases, results in an unpleasant odour, discolouration and/or soft or
slimy texture. However, in an appropriate environment, clostridium botulinum (a very
toxic organism that causes botulism) can grow without air and cannot be detected by
smell or taste. although it is extremely rare, it can be very dangerous.
To preserve foods safely, it is important to maintain low temperatures. You can signifi-
cantly reduce the growth of microorganisms at temperatures of 4ºc or below. freezing at
-17ºc does not kill microorganisms, but stops them from growing. for long-term storage,
always freeze perishable foods that have been vacuum packaged.
imPorTanT: Please note that vacuum packaging cannot reverse the deterioration of
foods. it can only slow down changes in quality. it is difficult to predict how long foods
will keep their quality, flavour, appearance, or texture, because this depends on the
type, date of production, and state of the food on the day it was vacuum packaged.
guidelines FOr preparing yOur FOOd
Vegetables need to be blanched before vacuum packaging. This process stops the
enzyme reaction, which leads to loss of flavour, colour and texture. To blanch vegeta-
bles, place them in boiling water or in the microwave oven for some minutes until they
are cooked but still crisp. Then, immediately immerse the vegetables in cold water to stop
the cooking process. finally, dry the vegetables on a towel before vacuum packaging.
some vegetables (broccoli, sprouts, cabbage, cauliflower, kale, turnips) naturally emit
gases during storage. Therefore, even after blanching, they must be stored in the freezer
only and are not suited for vacuum packaging.