Self-selection of food ingredients and agricultural by-products by the house cricket, Acheta domesticus (Orthoptera: Gryllidae): A holistic approach to develop optimized diets.

The house cricket, Acheta domesticus L. (Orthoptera: Gryllidae) is one of the most important species of industrialized insects in the United States. Within the past five years the market of cricket powder as a food ingredient has been growing with increasing consumer interest on more sustainable sources of food. However, high labor costs of cricket production and high prices of cricket feed formulations result in cricket powder market prices much higher than other protein-rich food ingredients, making cricket powder only competitive within the novelty food market. In this study new diets formulated using by-products were developed using dietary self-selection followed by regression analysis. Crickets selected among seven different combinations of ingredients. Consumption ratios of food ingredients and by-products were used to determine macro and micro-nutrient intake. Regression analysis was used to determine the individual nutrient intake effect on cricket biomass production. Intake of vitamin C, sterol, manganese, and vitamins B1 and B5 had the most significant impact on live biomass production. Four diets were formulated based on this information and compared with a reference (Patton's 13) and a commercial diet. Although, crickets reared on Patton's diet 13 produced the most dry-weight biomass and developed the fastest, diet 4 (consisting of 92% by-products) generated the most profit (with a cost of $0.39 USD per kg) after an economic analysis that did not include the commercial formulation. Dry-weight biomass production was not significantly different among the four new diets and the commercial diet. This study demonstrated the value of dietary self-selection studies in developing oligidic insect diets and in studies of insect nutrition. This is the first such study involving farmed edible crickets and agricultural by-products. Four new cricket diet formulations contain between 62 and 92% agricultural by-products are included.

Antinutritional factors and hypocholesterolemic effect of wild apricot kernel (Prunus armeniaca L.) as affected by detoxification.

The present investigation was aimed to study the effect of detoxification on the nutrients and antinutrients of wild apricot kernel followed by its hypocholesterolemic effect in male Wistar albino rats. The results revealed a non-significant (p > 0.05) effect of detoxification on the proximate composition except total carbohydrates and protein content. However, detoxification led to a significant (p < 0.05) decrease in l-ascorbic acid (76.82%), ß-carotene (25.90%), dietary fiber constituents (10.51-28.92%), minerals (4.76-31.08%) and antinutritional factors (23.92-77.05%) (phenolics, tannins, trypsin inhibitor activity, saponins, phytic acid, alkaloids, flavonoids, oxalates) along with the complete removal (100%) of bitter and potentially toxic hydrocyanic acid (HCN). The quality parameters of kernel oil indicated no adverse effects of detoxification on free fatty acids, lipase activity, acid value and peroxide value, which remained well below the maximum permissible limit. Blood lipid profile demonstrated that the detoxified apricot kernel group exhibited significantly (p < 0.05) increased levels of HDL-cholesterol (48.79%) and triglycerides (15.09%), and decreased levels of total blood cholesterol (6.99%), LDL-C (22.95%) and VLDL-C (7.90%) compared to that of the raw (untreated) kernel group. Overall, it can be concluded that wild apricot kernel flour could be detoxified efficiently by employing a simple, safe, domestic and cost-effective method, which further has the potential for formulating protein supplements and value-added food products.

Phenol-enriched olive oils improve HDL antioxidant content in hypercholesterolemic subjects. A randomized, double-blind, cross-over, controlled trial.

At present, high-density lipoprotein (HDL) function is thought to be more relevant than HDL cholesterol quantity. Consumption of olive oil phenolic compounds (PCs) has beneficial effects on HDL-related markers. Enriched food with complementary antioxidants could be a suitable option to obtain additional protective effects. Our aim was to ascertain whether virgin olive oils (VOOs) enriched with (a) their own PC (FVOO) and (b) their own PC plus complementary ones from thyme (FVOOT) could improve HDL status and function. Thirty-three hypercholesterolemic individuals ingested (25 ml/day, 3 weeks) (a) VOO (80 ppm), (b) FVOO (500 ppm) and (c) FVOOT (500 ppm) in a randomized, double-blind, controlled, crossover trial. A rise in HDL antioxidant compounds was observed after both functional olive oil interventions. Nevertheless, α-tocopherol, the main HDL antioxidant, was only augmented after FVOOT versus its baseline. In conclusion, long-term consumption of phenol-enriched olive oils induced a better HDL antioxidant content, the complementary phenol-enriched olive oil being the one which increased the main HDL antioxidant, α-tocopherol. Complementary phenol-enriched olive oil could be a useful dietary tool for improving HDL richness in antioxidants.