Effects of Biofermented Feed on Zophobas morio: Growth Ability, Fatty Acid Profile, and Bioactive Properties

The global population's increasing demand for sustainable and nutritious food sources has led to the exploration of alternative approaches in livestock production. Edible insects have emerged as a promising solution due to their nutritional composition, including high protein content, balanced fats, minerals, vitamins, and bioactive peptides. Biofermentation offers a viable method to enhance the nutritional value of insect feed. This study aimed to investigate the effects of feeding biofermented feeds derived from less valuable raw materials on the yield and nutritional composition of Zophobas morio larvae. The focus was on assessing fat quality, omega-3 and omega-6 fatty acids, and bioactive compounds and monitoring the larvae's weight and length increases. Three feed types were tested: wheat bran (control), fermented wheat bran, and a mixture of fermented corn and flaxseed in a five-week period. The findings demonstrated a noteworthy (p < 0.05) elevation in polyunsaturated fatty acids, such as gamma-linolenic acid, alpha-linolenic acid, and eicosapentaenoic acid in Zophobas morio larvae fed with biofermented corn and flaxseed pomace, both pre- and postculinary treatment, as compared to the control group. The study also showed increased chelation of Cu2+ (p < 0.05) and Fe2+ (p < 0.05) between native and roasted insects in the samples without in vitro digestion, as well as increased Cyclooxygenase-1 activity (p < 0.05), indicating improved bioavailability. Additionally, culinary processing led to a reduction in polyphenol content (p < 0.05), antioxidant activity (p > 0.05) except DPPH, and peptide concentration (p < 0.05) in the samples without in vitro digestion.