Explore the Vital Role of Vacuum in the Food Industry
The food industry faces around 1.3 billion tonnes of food wasted or lost annually worldwide. Vacuum technology is playing a vital role in various aspects of food technology. Amongst the various aspects, vacuum packaging is gaining prominence mainly due to its ability to increase the longevity of food by reducing the growth of bacteria and fungi. Similarly, vacuum cooling helps keep fruit and vegetables fresh directly after harvesting by enabling food containers to be evacuated to pressures of > 6 mbar. Vacuum drying helps preserve fresh fruit and meat through Vacuum Microwave Drying. Here the products are heated by microwave to 35-60 deg C while the vacuum pump keeps the pressure around 10 mbar. The water content then evaporates. Through Freeze Drying the products are cooled to -20-40 deg C and the water sublimates at pressures below 0,1 and -1 mbar from the solid phase [1].
Considerable progress has been made in the processing of foods using operations viz. drying, evaporation, distillation, concentration, centrifugation, filtration, irradiation, freeze drying, osmotic drying etc. to get ready to eat food, convenience food, precooked dried food, preserved food. Vacuum technology in direct or indirect ways has played a vital role in carrying out these food processing operations. Food materials like farm fresh fruits and vegetables, meat and flesh foods start deteriorating shortly after harvest due to bacteria, microorganisms, insects in addition to biochemical and physiological changes. Therefore, the availability of food supplies can be increased effectively by using various food process methods in which vacuum is used extensively
The traditional methods of food preservation like smoking curing, pickling, canning and drying can augment food supplies by preventing natural deterioration. But, these methods cause changes in color, taste, flavor, texture and other organoleptic attributes of food. Refrigeration preserves for a limited period. Freezing and quick freezing improves the storage stability. Freeze drying is capable of extending the storage life of foods by two years at room temperature conditions retaining taste, flavor and other original properties of foods. Long term storage is affected by using suitable packaging materials, viz. high and low density polyethylene, cellophane, aluminum laminate pouches or nylon bags.
