Food safety is the responsibility of the growers, manufacturers and processors and food handlers. The supply to consumers is in different forms such as fresh, preserved and processed products of plant, animal and marine origin.
During the past two decades, numerous researches on food preservation using emerging technologies have been developed. Since these processing techniques have little or no new thermal effects on food, they are commonly referred to as non-thermal preservation technologies. Among these emerging technologies, the most promising ones for food application are high-pressure processing and use of pulsed electric fields. Although the fact that high pressure kills microorganisms and preserved food in the early 19th century, its commercial benefit became available to the food processing industry in a decade ago, stated officials at IICPT.
The concept of high pressure treatment of foods involves subjecting food materials to pressures as high as 9,000 times the atmospheric pressure. It is uniformly applied throughout a food material independent of its mass and time, they added.
Typically, the pressurisation time for foods is independent of the quality of food placed in the pressure vessel, The presence of air in the food increases the pressurisation time, since air is more compressible than water.
According to IICPT, in contrast to the thermal treatment, high pressure processing does not break the ‘covalent bonds’ in food, and thus helps to preserve the flavour. The effect of high pressure on enzymes is largely due to the nature of the proteins.
In fact, the first commercial production of high pressure processed jam was carried out in Japan in 1992, which was well received by consumers. Since then a diverse range of foods, including fruit juices, vegetables, milk, yoghurt, cheese, fish, pork, beef, ice cream, Japanese unrefined rice wine and rice cakes containing herbs are processed using this technology, stated IICPT.
The non-availability of suitable equipment burdened early application of high pressure. There has also been considerable progress made in equipment design which has ensured global recognition of the potential for such technology in food processing. Moreover, high pressure technology can supplement conventional thermal processing for reducing microbial load or substitute the use of chemical preservatives. The advantage of high pressure technology includes that it enables, food processing at ambient temperature or even lower temperature. Causes of microbial death leads to improvements in overall quality of foods and it can be used to create ingredients with novel functional properties.
The food technologists globally recommend high pressure processing to prevent hazardous micro-organisms like E Coli, Salmonella and Vibrio. Presently the food industry is interested in eliminating the harmful organisms.
IICT officials’ said that High pressure processing was not likely to replace traditional methods. However, they observed that high capital expenditure could limit the application initially but this could be offset by lowering the cost expenses of lower operating costs if efficient energy systems were used.
