Optimization of Drying Parameters for Hermetia illucens Using Oven Drying

Abstract

Insects are frequently dried to retain their nutritional quality. The influence of drying temperature and drying time has an effect on the crude lipid yield. The greater moisture loss will lead to a higher lipid yield. Inactivation of larvae by means of freezing followed by oven drying indicates a high amount of free fatty acids. The total fatty acid concentration in Hermetia illucens prepupae was mainly comprised of saturated fatty acids followed by monounsaturated fatty acids and polyunsaturated fatty acids. A substantial amount of lauric acid was discovered and may be beneficial in animal feed. The optimum crude lipid yield and moisture loss temperature were determined.

Evaluation of the interrelated effects of slaughtering, drying, and defatting methods on the composition and properties of black soldier fly (Hermetia illucens) larvae fat

“…This effect could be explained by the existence of active lipolytic enzymes in these samples. In fact, there is previous evidence in the scientific literature that has shown the relevance of lipase activities in edible insects, being especially intense in the case BSFL ( Caligiani et al, 2019 ; Leong et al, 2022 ; Ravi et al, 2020 ). During the slow slaughter of BSFL by freezing, Leni et al (2019) identified different metabolites that indicated that energetic metabolisms are stimulated, such as the hydrolysis of glucose, production of lactic acid, consumption of citric acid, and lipolysis of TGs.…”

“…Different examples can be found about the strong lipolysis process in BSFL when non-thermal methods of slaughtering are employed. Thus, Leong et al (2022) and Ravi et al (2020) already suggested the necessary thermal slaughtering of BSFL to avoid an evident lipolysis, since even more restrictive freezing temperatures of −80 °C were insufficient to inactivate the lipolytic enzymes. Furthermore, Caligiani et al (2019) demonstrated that the BSFL lipase remains active, and lipolysis continues, during the freezing time of storage, although the greatest activity seems to be found immediately after slaughtering.…”

“…The high lipase activity found in insects has been related to intense lipolysis of lipids and a subsequent increase in the acidity. This parameter is related to worse quality of edible fats due to the loss of the integrity of the fat to free fatty acids (FFAs) and partial glycerides ( Caligiani et al, 2019 ; Leong et al, 2022 ; Santana et al, 2017 ; Terra and Ferreira, 2012 ). Furthermore, such modification of the lipid profile might have a direct impact on the technological properties of fat because the melting and crystallization temperatures of lipids vary depending on the lipid species composition.…”

“…Furthermore, such modification of the lipid profile might have a direct impact on the technological properties of fat because the melting and crystallization temperatures of lipids vary depending on the lipid species composition. Thus, the use of thermal methods for either killing or drying of insects, such as blanching and oven-drying, seems to prevent the lipolysis of lipids, in contrast with non-thermal methods, as freezing or freeze-drying ( Caligiani et al, 2019 ; Leong et al, 2022 ). However, these lipolytic effects have been mainly related to the slaughtering step, but conclusive results regarding the impact of the entire processing of BSFL on lipid composition have not been reached.…”

The Interaction of Slaughtering, Drying, and Defatting Methods Differently Affects Oxidative Quality of the Fat from Black Soldier Fly (Hermetia illucens) Larvae

“…For example, after testing different killing methods, Larouche et al (2019) [17] and Zhen et al (2020) [19] remarked blanching as the preferred method for all the quality parameters of BSFL meals, including low lipid oxidation. Concerning drying methods, either thermal methods such as oven or microwave, as well as non-thermal methods such as freeze-drying, have been tested [20,21]. However, no conclusive results have been reached regarding the impact of the drying methods on lipid oxidation, likely due to the dependence on the slaughtering method used.…”