Insect biomass is characterized by rich protein content while it also contains many other essential nutrients. Due to favorable nutritional properties and relatively cheap methods of cultivation, insects are becoming an interesting topic in the search for new alternative sources of nutrients. With lactic acid fermentation we could enrich insect biomass even further and increase its nutritional value. During fermentation complex molecules are converted into simpler and biologically more accessible molecules, giving the final product a range of proven positive effects. Two lyophilized biomasses of insects, a mealworm and a house cricket, were exposed to three conditions of lactic acid fermentation: spontaneous fermentation, fermentation with L. plantarum inoculum and fermentation with a commercial meat culture. The samples were fermented for 48 h and analyzed at three different times (0, 24 and 48 h). Through various analyses of fermented products (determining the colony forming units, pH measurement, determining the concentration of lactic acid and verification of protein hydrolysis by determining the concentrations of free amino groups and by SDS-PAGE) we monitored the dynamics of fermentation between samples and evaluated the end products. We found that fermentation was most pronounced in the first 24 h. The greatest increase in the concentration of fermentation end products (lactic acid and free amino groups) was measured in samples during fermentation with L. plantarum inoculum, which grew equally well on both substrates.
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