Efeito de diferentes técnicas de secagem sobre as propriedades nutricionais de larvas da mosca soldado negro (Hermetia illucens L)

Abstract

By 2050, the UN predicts a world population of 9.7 billion. To meet the protein needs of this population, food production will have to increase by 70% and there are several challenges to be overcome to reach this goal. Insects have proven to be a sustainable alternative to this protein demand and the black soldier fly (BSF, Hermetia illucens L.), has stood out for its high protein value and ease of rearing in relation to other insects, besides also being a source of lipids and fatty acids and its nutritional value also includes chitin that acts as a fiber. The influence of different drying techniques - fixed bed drying (FBL), oven drying (ES), wind tunnel drying (WT) under different temperatures (50; 55 and 60ºC); sun drying (SUN) and microwave drying (MO) in powers 20 and 50% - on the final moisture content and on the nutritional value (protein, lipid and ash content) of black soldier fly larvae was analyzed. A randomized block design (RDB) was used in a factorial scheme (3 x 3) + 3 additional controls. Data were subjected to variance analysis and for comparisons of means Tukey's test and Dunnett's test were used. Significant differences were found mainly for lipid content after the application of the drying techniques. The results showed that higher temperatures and conditions tend to favour the increase in lipid content in the dried material, calculated under the same moisture content. LF drying at 55ºC returned the highest result (35.24% ± 0.72) statistically comparable to LF-60 (35.00% ± 0.07), MO-50 (34.77% ± 0.28) and TV-60 (34.61% ± 0.17). In contrast, proteins (via Kjeldahl) returned higher values in less strenuous conditions. WT at 50ºC (36.42% ± 0.79) and greenhouse at the 3 temperatures surveyed (35.71% ± 0.80; 36.10% ± 1.69 and 35.49% ± 0.80) provided the highest results for protein. These studies will contribute to the establishment of an efficient means of drying for BSF larvae. We also present a survey on the pre-treatments that should precede drying to ensure the best food safety.