The influence of LAB fermentation on lycopene and β- carotene content in different species of tomatoes

The aim of the study was to determine the changes of lycopene, lycopene isomers, ß–carotene and total carotenoid content in different species of tomatoes, fermented by different lactic acid bacteria and self–contained leaven, and to evaluate the color coordinates changes in these products and their correlation with carotenoid content. Two species of tomatoes: \"CUNERO\" and \"Ronald\" were grown in soil in greenhouses of Lithuanian Institute of Horticulture (LIH) (2010 harvest). The first phase of work was to defrost and homogenize tomatoes, and undergo a spontaneous fermentation with yeast and starting microorganisms: Lactobacillus sakei, Pediococcus pentosaceus and Pediococcus acidilactici. On the next stage of work, the samples were prepared for spectrophotometric qualitative and quantitative analysis of lycopene and ß–carotene, evaluation of total carotenoid content. The spectrophotometry of fermented and unfermented tomato color coordinates of the flat-contrast color space was estimated also. Research data was evaluated with the means of statistical “Prism 3.0.” package and Microsoft Excel. It was found that the matrix of the fermentation characteristics and fermentation conditions influence ß–carotene levels in Ronald and CUNERO tomato species. By overall amount of carotenoids RONALD tomato species is more valuable by nutritional aspect, because they have the total carotenoid content of more than CUNERO tomato species (0.217 mg per 100 g or more). In different tomato samples some of the color coordinates (a, b, l and c) trends in the fermentation are the same, depending on the microorganisms used in fermentation, but this tendency was not found for color tone. According yellow coordinates it is possible to evaluate the amount of lycopene in RONALD samples (r = 0.8248, P = 0.0329), while the purity of tone and color can not be judged on the total carotenoid content of tomato samples (r = 0.4974, P = 0.1834)