Comparaison de différentes techniques de prétraitement et de séchage sur la charge microbienne, les caractéristiques physicochimiques et nutritionnelles des larves de mouches soldats noires (Hermetia illucens) comme aliment alternatif pour l'alimentation animale.
|Advisor:||Ratti, Cristina; Saucier, Linda; Vandenberg, Grant William|
|Abstract:||Black soldier fly larvae (Hermetia illucens; BSFL) are an alternative source of protein and energy for livestock feeding. Many aspects related to process optimization to ensure the safety, conservation and nutritional quality of this new ingredient are still unknown. The presence of a wax-coated cuticle, to reduce drying of the larvae, constitutes a barrierto evaporation. The purpose of this study was to optimize larval conditioning and drying techniques to effectively reduce their water content and microbial load in order to establish the processing parameters into larval meal required by the Canadian Food Inspection Agency while minimizing negative impacts on nutritional quality. After 10 days of feeding on a Gainesville control diet at 27°Cand 70% moisture, BSFL were collected by sieving, they were rinsed with sterile water, packaged under vacuum, frozen at -40°C (n=3 replicates). After thawing, aliquots of 30g/treatment (n=3) were pretreated, or not, by blanching (100°C for 40s), boiling (100°C for 2, 4, 6 or 8 min) or mechanically perforated before being hot-air dried (60°C) or freeze-dried (40°C) until a final water activity ≤0.3 was obtained for the larval meal. The microbiological quality of the larvae was assessed by enumeration of total aerobic mesophilic (AMT), Pseudomonasspp., Listeriaspp., presumptive lactic acid bacteria, Enterobacteriaceae and coliforms. The impact of drying techniques on physicochemical and nutritional properties have been evaluated using colour (L*, a*, b*), larval pH before and after processing, lipid oxidation (xylenol orange, TBARS) and proximal composition including lipid and protein levels. The results demonstrate that the initial larvae contamination (9logCFU/g AMT of fresh larvae on dry basis) was reduced by 3 to 4 log CFU/gafter a pre-treatment followed by hot air drying (60°C); 4min boiling at 100°C followed by hot air drying at 60°C for 6h was found to be the optimal treatment parameter.|
|Document Type:||Mémoire de maîtrise|
|Open Access Date:||13 December 2019|
|Collection:||Thèses et mémoires|
All documents in CorpusUL are protected by Copyright Act of Canada.