There are great expectations about real attack of the domestic market by fruits and vegetables grown in Russia that have gained a considerable "political weight" recently. But being domestic is not enough to be registered on the shelves of retailers for a long time, it is also necessary to have good «best before» dates. It has been a problem till now. Scientists of Kemerovo Technological Institute of Food Industry offer to use biokonservant based on lactic acid bacteria for vegetables and fruits "life extension".
Searching for technologies by which one could safely extend the shelf life of fruits and vegetables, is being conducted in many laboratories around the world. Two approaches dominate (we dont take into account chemical preservatives and gene modification, frightening Russian consumer). One of them is the use of vacuum packaging with variable and modified composition of the gas medium. Such "smart wrapper" is capable to change its properties under external influence and control the inner space influencing physical, chemical or biological properties of the product. The technology has been about twenty years in developed countries, including Russia, and is constantly being improved.
Another trend - the use of natural preservatives - metabolites of microorganisms, in particular bacteriocins. These are antibacterial substances of protein nature. Promising bacteriocins producing strains used in the food industry are lactic acid bacteria. People have been using the antimicrobial effect of this group of bacteria for centuries in one way or another, particularly for extending the shelf life of food products. Nowadays, these microbes are also held in high esteem: diverse products of bacteriocins are used in Western countries in the production of yogurt, salami (in Italy), harvesting of Spanish olives.
In Russia, natural preservatives are studied be the team of Kemerovo Technological Institute of Food Industry researchers, headed by Olga Babich, director of the Institute of Biotechnology in the structure of the institute.
Scientists intend to obtain biokonservant, allowing increasing the shelf life of perishable fruits and vegetables up to 20 days.
"To do this, from the surface of fresh fruits and vegetables we obtain the desired lactic acid bacteria - Lactobacillus, which are contained in the normal microflora - Olga Babich says about the intricacies of technology. Then we study their antimicrobial activity against major pathogens that stimulate the decay, and select the most active strains. We identify, isolate and purify bacteriocins, produced by these microorganisms. We create a biological preservative on their basis - a solution consisting of Lactobacillus metabolites, including bacteriocins.
They can be used for safe handling of fruits and vegetables, prolonging their retention periods. Natural preservative is washed off with water before using the product".
Scientists have already selected strains of lactic acid microorganisms, which will be used in further research, and found baktriotsins, produced by them. Scientists are currently experimenting with apples and pears. Fruits are immersed in a biokonservant solution and smoothly dried in a stream of air, thus prolonging their youth.
According to participants of the project, the biokonservant they developed has several advantages over the known world and domestic counterparts in the spectrum of antimicrobial activity, as well as in the cost.
The next phase of the project - patenting and developing technical documentation on biokonservant (laboratory production schedules on producing the biokonservant, project specifications on biokonservant), industrial testing of technology, which will be held in Spain in the TECNOVA company, acting as the foreign partner of Kemerovo Technological Institute in this project. The company has laboratories for pre- and post-harvest researches, for physical and chemical analysis of raw materials and food products, environmental chambers for semi-industrial tests, as well as their own greenhouses for testing of new crops.
The project "Development of technology for biokonservant based on bacteriocins of lactic acid bacteria to increase the shelf life of fruits and vegetables" is supported by Federal Targeted Programme for Research and Development in Priority Areas of Development of the Russian Scientific and Technological Complex for 2014-2020.