Lipid and amino acid profiles support the potential of Rhynchophorus phoenicis larvae for human nutrition

This work was supported in part by the SCAC (Service de Coopération et d’Action Culturelle) of the French Ambassy of Yaoundé – Cameroon [Code projet Prisme/Numéro Prisme: 0185 CMR B16 0011]The authors wish to thank Lucie Ribourg, Marion De Carvalho and Mathieu Fanuel for helping us in tocopherol analysis, DSC analysis of lipid extracts and MALDI TOF analysis of TAGs structures. We also thank John Fogoh Muafor from Living Forest Trust (LIFT) and Ministry of Forestry and Wildlife (Cameroon) for providing the larvae from the wild

anglais. In view of future use of insects in the diet, Rhynchophorus phoenicis larvae were evaluated for their potential as protein and lipid sources. Their lipid and protein contents represented 21.35 +/- 2.01 g/100 g and 8.18 +/- 0.44 g/100 g fresh weight (FW), respectively, with energy content of 940.0 kJ (224.9 kcal)/100 g FW. Indispensable amino acids were in higher amounts than in Food and Agriculture Organization (FAO) reference protein, with remarkably high scores for tryptophan and sulfur amino acids. Total lipids comprised neutral lipids (97.53 +/- 0.05 g/100 g lipid), glycolipids (0.59 +/- 0.04 g/100 g), phospholipids (1.88 +/- 0.06 g/100 g) and tocopherols (146 +/- 13 mu g/g). Total and neutral lipids had palmitic and oleic acids (38 and 46 g/100 g total fatty acids, respectively) as main fatty acids, and palmitoyl, dioleylglycerol (POO) (36.4 +/- 0.3%) and dipalmitoyl, oleylglycerol (PPO) (30.3 +/- 0.3%) as main triacylglycerol molecular species. This composition explains the lipid melting/crystallization profile. Polyunsaturated fatty acids represented 0.76 +/- 0.17 g/100 g fresh larvae (linoleic acid: 0.58 +/- 0.11 g/100 g; alpha-linolenic acid: 0.17 +/- 0.06 g/100 g). They concentrated in the phospholipids, characterised by a majority of choline-carrying species and high levels of lyso-phospholipids. These results confirm that Rhynchophorus phoenicis larvae are a potential alternative source of dietary fat and proteins that can be used to address under-nutrition and malnutrition