Statistical optimization of agro-industrial diets for the rearing of Cydia pomonella using response surface methodology

In this study, apple pomace and brewery wastewater were used as nutritive agents and as alternative substitutes for the ingredients (soya flour, wheat germ and yeast extract) without affecting the production of the diet. The quantity of agro-industrial waste added during production was based on a regime where the different nutrients were maintained as a constant, such as proteins (3.71 ± 0.09 g), carbohydrates (4.2 ± 0.12 g) and lipids (2 ± 0.08 g) based on their concentration in the standard diet. Various diets produced using different concentrations of waste and ingredients were tested using the culture of Cydia pomonella in order to optimize the diet in terms of nutrition and optimal viscosity (to facilitate assimilation of nutrients). Optimization of the rearing parameters was carried out using response surface methodology. This demonstrated that the brewery wastewater (BWW-SF) diet provided the best results for insect-rearing (81% hatching, 76% larvae and 51% adults) which was closer to the control diet (90% hatching, 80% larvae and 65% adults) and was more significant than the other diets (40– 70% hatching, 45–50% larvae and 9–30% adults). In addition, the viscosity was higher in diets where the solids content was higher. The increase in viscosity was in line with the solidification of agar, which evolved rapidly over time and in relation to the solids present in the diet.