Interestingly, it has been proved that lysozyme action against thermophilic bacterial strains (all tabulated strains are noticeably thermophilic and inclusive) is available within a range of C (Hughey and Johnson, 1987). This is especially true for thermophilic spore-formers and it is reported that the enzyme can be used post-thermal sterilisation to enhance shelf longevity (Hughey and Johnson, 1987). It has also been proved that pathogenic bacteria can be inhibited in food by a combination of hydrostatic pressure and heat at lower temperatures than heat alone (Alpas, H., et al, 1999;). It is noted here that many foodborne pathogenic bacteria that are both gram-negative and positive have an enzyme DegP protease (C Hal, J., et al, 2001) that ensures their thermal stability. Targeting this enzyme or the gene that initiates it by either thermal or any other process would much increase death rates in these bacteria easily. It is also necessary to effectively assess the time required to initiate or complete phases other than the death phase to do this (McMeekin, T.A., et al, 1997). It is also noted at first that some of the literature is dated but care has been taken to incorporate only information that is still germane and effective today. In this some original research papers that are still quoted today as legitimate sources have been utilised. The paper finds, primarily, that foods that cannot be heated should be stored at such low temperatures that both psychrophilic and thermophilic bacteria cannot regenerate. Foods that can be heated should be heated to such a temperature that at least all possible vegetative cells of possible pathogenic bacteria be killed and should either be eaten immediately or stored at cold temperatures such that spores, if present, cannot regenerate upon longer periods of storage.
A U.S. Department of Agriculture report - the Agricultural Economic Report No. 741, 1996 - reported that microbial pathogens in food cause 6.5-33 million cases of human illnesses and 9,000 deaths in America. The report, though slightly backdated, is utilised here because it is one of a kind and one as comprehensive as it is not available for more recent times. It estimates that over 40 such foodbourne microbial agents - viruses, bacteria, fungi and parasites - are responsible for these illnesses. The medical and productivity costs of both acute short-term and chronic long-term illness conditions are considerable. For just six bacterial pathogens, the costs are $9.3-$12.9 billion annually of which $2.9-$6.7 billion annually is attributed to foodbourne bacteria (Report No. 741, 1996). Though the figures are of 1996 recent literature on the subject concede that the problem remains extensive enough and provides impetus to the purpose of this paper.
Nature of Bacteria
To better understand how bacterial growth is influenced by the combination of temperature and food composition it is somewhat