Food Preservation is the process through which minimizing the biochemical, physical and nutritional damage of food. It is estimated that large amount of food products are lost each year due to spoilage. In each step of food processing contamination may take place to reduce this microbial contamination biotech techniques are applied. So there is some Biotechnological technique used for food preservation. Recent years many food industries represent immense role of food biotechnology. GM plants and animals are used to enhance taste, shell life, nutrition and quality of food. GM yeast and Bacteria are used to produce enzymes in food industry.
Biotechnology tools used for food preservation
Recombinant Antifreeze Protein (rAFP): Antifreeze proteins are potent cryogenic protection agents for the cryopreservation of food and pharmaceutical materials. A food assessment expression and fermentation system for the production and secretion of high levels of rAFP was developed. A novel recombinant type I antifreeze protein analogue (rAFP) was produced and secreted by Lactococcus lactis, a food-grade microorganism of major commercial importance. Lyophilized, crude rAFP produced by L. lactis was tested in a frozen meat and frozen dough processing model. Frozen dough treated with the rAFP showed better fermentation capacity than untreated frozen dough. Breads baked from frozen dough treated with rAFP acquired the same consumer acceptance as fresh bread. So this approach is using present scenario.
Use of High Pressure Processing: It is a non thermal and highly capable preservation technique. Basically focus on inactivating those bacteria which are responsible for food disease. In this technique high pressure (100-1000 MPa) is applied to inhibit the bacterial growth without disturbing texture, taste, nutrition and mineral quality of food. It is safe for both type of liquid as well as for solid product.
Hurdles Technology: It is a combination of different preservative methods like use of high temperature in processing, low temperature for storage, increase acidity, low water activity, reduce redox potential and the presence of different preservatives to favor the growth of desirable bacteria and inhibit the growth of pathogenic bacteria.
Bacteriocins: These are the complex protein, added during food processing; these proteins are active against food spoiling microbes.
Chelating agents: Due to their binding ability with lipopolysaccaride layer of microbes, chelating agents helps bacteriocins protein to prevent microbial growth.
Fermentation starter culture: In fermentation technique complex material is converted into simple substance with the help of enzyme. In this process lactic acid is produced which decreases the pH of medium, due to acidic medium and low water activity, prevent biological growth in medium to insure prolong preservation of food.
Radiation: In this process, food products are exposed under the ϒ-radiation having frequency 0.1-0.5 kGy. Radiation cause metabolic changes to increase the shelf life.
Products preserved through biotechnology
Meat and Sea food: Most of the world population is nutritionally depends on meat (flash of animal) and sea food. Due to high consumer demand and low shelf-life quality its preservation is challenging so new approaches are developed alike use of fermentation starter culture, use of sakacin and pediocin (bacteriocins), with ultra high pressure and pulse electric field some time chelating agents also used with bacteriocins. The frozen meat treated with the antifreeze protein showed less drip loss, less protein loss, and a high score on juiciness by sensory evaluation.
Milk and dairy product: Milk is a good source of calcium and minerals, considering as a complete health drink. Current research indicates that act as carrier for pathogenic microbes. Pasteurization is generally used to decrease the microbial growth, although, it will not applicable a complete sterile milk product. Hence use of Bacteriocins seems good approach to improve the safety and quality of milk or dairy products.
Fruits and Vegetables: Soft overcoat of fruits and vegetables are responsible for damage its nutrient value. Controlled and modified atmospheric storage, active packaging, minimal processing, hurdle technology, fogging technology and ϒ radiation are use for fruit and vegetable preservation.
Fermentation Product: The genus Lactobacillus is a heterogeneous group of lactic acid bacteria (LAB) with important implications in food fermentation. The ability to colonize a variety of habitats is a direct consequence of the wide metabolic versatility of this group of LAB. Consequently, lactobacilli have been used for decades in food preservation, as starters for dairy products, fermented vegetables, fish and sausages as well as silage inoculants. Lactobacilli have also been proposed as probiotics and microbial cell factories for the production of nutraceuticals. However, a wide range of applications of lactobacilli in food biotechnology remains potential.
Genetically Modified Organisms in Preservation: Microorganisms are an integral part of the processing system during the production of fermented foods. Microbial cultures can be genetically improved using both traditional and molecular approaches and improvement of bacteria, yeasts and moulds is done. One of the traits which have been considered for commercial food applications in both developed and developing countries include the ability to produce antimicrobial compounds (e.g. bacteriocins, hydrogen peroxide) for the inhibition of undesirable microorganisms. In many developing countries, the focus is also on the degradation or inactivation of natural toxins (e.g. cyanogenic glucosides in cassava), mycotoxins (in cereal fermentations) and anti-nutritional factors (e.g. phytates).
Biotechnology has tremendous potential for increasing food production and improving food processing in food industries. Productivity must first increase in developed countries before real benefits can be reaped in developing countries. Where biotechnologies are applied to production destined for domestic markets, "demonstration effects" can stimulate developments in other countries. In this case, there is considerable scope for cooperation among developing countries. However, where the application of this new technology aims to increase productivity in the export sectors, successes in some countries could be at the expense of the market position of others.