Protein films from black soldier fly (Hermetia illucens, Diptera: Stratiomyidae) prepupae: effect of protein solubility and mild cross‐linking

BACKGROUND The present work evaluated the performances of protein‐based bioplastics obtained from black soldier fly prepupae (Hermetia illucens). Protein films were synthesized by film casting, both using the whole proteins and their soluble fraction at pH = 10. The effects of glycerol as a plasticizer and of citric acid as a mild cross‐linker onto film properties were also evaluated. RESULTS Films obtained using the soluble protein fraction resulted the strongest, as well as the most homogeneous, and transparent ones. Protein mild cross‐linking improved their tensile properties, especially in films obtained with the whole protein fraction. Non‐cross‐linked samples had a high affinity with water while cross‐linking almost eliminated the ability of films to absorb water. All protein‐based films proved to be an effective barrier to red‐light (T% < 2). CONCLUSION Bioplastics derived from black soldier fly prepupae may find applications in the agricultural sector (biodegradable pots, mulching films, utensils) and deserve to be tested for food and non‐food packaging.