Effect of Different Storage Methods on the Microbiological Quality of the Insect Dry Powder Made from Mealworm (Tenebrio molitor, L.)

Abstract

Entomophagy as an alternative way of eating in the Czech Republic is gaining more and more supporters. For this reason, we have focused on the microbial quality of the insect dry powder made from Tenebrio molitor during storage. In the samples were determined the major groups of microorganisms by standard procedures. It is the total number of microorganisms, aerobic microorganisms thermoresistant, E. coli and other coliform bacteria, micromycetes and bacteria of the genus Enterococcus. The highest increase of total microorganisms occurred after five months storage in the sample stored in a paper bag and cold, where their number reached a value of 2.870 log CFU/g. For the same sample, coliform bacteria at the rate of 1.839 log CFU/g were also detected. The other monitored groups of microorganisms were in the samples at most in the order of tens of CFU/g. The results of our research show that the microbiologically tested the insect dry powder is a very stable material. After eight months of storage, there was only a minimal increase in count of microorganisms. Based on the results, it is not possible to decide clearly which storage conditions are most appropriate. In our opinion, storage in a paper bag at a temperature of 22-23 oC is considered to be very convenient, whereas storage at 4-6 oC and 90% humidity cannot be recommended because of the higher incidence of mold due to high humidity in the refrigerator. Due to the small number of expert publications dealing with this issue, it is necessary to continue to address this topic.