Dietary enrichment of edible insects with omega 3 fatty acids

International audienceEdible insects are advocated as sustainable and healthy food and feed. However, commercially produced insects are often low in n-3 fatty acids and have suboptimal n-6/n-3 ratios. A certain amount and proportion of these FAs is required to optimize human health. Flaxseed oil consists primarily (57%) out of alpha-linolenic acid. An experiment was conducted to quantify the effect of flaxseed oil provision on fatty acid composition and to determine the quantity needed to attain a beneficial n-6/n-3 ratio. Three species were used in the experiment: house crickets (Acheta domesticus [L.]), lesser mealworms (Alphitobius diaperinus [Pfanzer]) and black soldier flies (Hermetia illucens [L.]). These were provided with either a control diet or a diet enriched with 1%, 2%, or 4% flaxseed oil during their larval/nymphal stage. Fatty acid profiles of diets and insects were determined via GC-MS. The three species had distinct fatty acid profiles on all four diets, but responded similarly to flaxseed oil addition. For each percent added to the diet, the alpha-linolenic acid content of the insects increased by 2.3%-2.7%. Four percent addition increased the n-3 fatty acid content 10-20 fold in the three species and thereby strongly decreased n-6/n-3 ratios from 18-36 to 0.8-2.4. A ratio below 5 is considered optimal for human health and was achieved by 2% flaxseed oil inclusion for house crickets and lesser mealworms, and at 1% inclusion for black soldier flies. Adding a source of n-3 fatty acids to insect diets can thus improve the nutritional quality of insects

Dietary enrichment of edible insects with omega 3 fatty acids

Edible insects are advocated as sustainable and healthy food and feed. However, commercially produced insects are often low in n-3 fatty acids and have suboptimal n-6/n-3 ratios. A certain amount and proportion of these FAs is required to optimize human health. Flaxseed oil consists primarily (57%) out of alpha-linolenic acid. An experiment was conducted to quantify the effect of flaxseed oil provision on fatty acid composition and to determine the quantity needed to attain a beneficial n-6/n-3 ratio. Three species were used in the experiment: house crickets (Acheta domesticus [L.]), lesser mealworms (Alphitobius diaperinus [Pfanzer]) and black soldier flies (Hermetia illucens [L.]). These were provided with either a control diet or a diet enriched with 1%, 2%, or 4% flaxseed oil during their larval/nymphal stage. Fatty acid profiles of diets and insects were determined via GC-MS. The three species had distinct fatty acid profiles on all four diets, but responded similarly to flaxseed oil addition. For each percent added to the diet, the alpha-linolenic acid content of the insects increased by 2.3%–2.7%. Four percent addition increased the n-3 fatty acid content 10–20 fold in the three species and thereby strongly decreased n-6/n-3 ratios from 18–36 to 0.8–2.4. A ratio below 5 is considered optimal for human health and was achieved by 2% flaxseed oil inclusion for house crickets and lesser mealworms, and at 1% inclusion for black soldier flies. Adding a source of n-3 fatty acids to insect diets can thus improve the nutritional quality of insects.</p

Insects as sources of iron and zinc in human nutrition

Dietary deficiencies in Fe and Zn are globally widespread, causing serious health problems such as anaemia, poor pregnancy outcomes, increased risk of morbidity and mortality, stunted growth and impaired physical and cognitive development. Edible insects, of which a diversity of over 2000 species is available, are dietary components for about 2 billion individuals and are a valuable source of animal protein. In the present paper, we review the available information on Fe and Zn in edible insects and their potential as a source of these micronutrients for the rapidly growing human population. The levels of Fe and Zn present in eleven edible insect species that are mass-reared and six species that are collected from nature are similar to or higher than in other animal-based food sources. High protein levels in edible insect species are associated with high Fe and Zn levels. Fe and Zn levels are significantly positively correlated. Biochemically, Fe and Zn in insects occur predominantly in non-haem forms, bound to the proteins ferritin, transferrin and other transport and storage proteins. Knowledge gaps exist for bioavailability in the human alimentary tract, the effect of anti-nutritional factors in other dietary components such as grains on Fe and Zn absorption and the effect of food preparation methods. We conclude that edible insects present unique opportunities for improving the micronutrient status of both resource-poor and Western populations.</p

Absorption of iron from edible house crickets: a randomized crossover stable-isotope study in humans

Background Edible insects are a novel source of animal protein. Moreover, edible insects contain iron concentrations similar to meat, potentially making them a valuable iron source for human consumers. Yet, it is unknown to what extent iron from insects is absorbed in humans. Objectives In this exploratory study, we assessed fractional iron absorption from house crickets (Acheta domesticus) consumed with refined (low-phytate, noninhibiting) or nonrefined (high-phytate, inhibiting) meals. Methods Intrinsically [57Fe]-labeled and control crickets were reared. Six iron-balanced experimental meals were randomly administered crossover to 20 iron-depleted females (serum ferritin <25 µg/L; 18–30 y old), in 2 time-blocks of 3 consecutive days, 2 wk apart. Three meals consisted of refined maize flour porridge with either [57Fe]-labeled crickets, [58Fe]SO4 (reference meal), or unlabeled crickets plus [54Fe]SO4. The other 3 meals consisted of nonrefined maize flour porridge with the same respective additions. Blood samples were drawn to assess the 14-d isotope enrichment in erythrocytes, and meal-specific fractional iron absorption was calculated. In vitro digestion was used to explore possible explanations for unexpected findings. Results Mean fractional iron absorption from 57Fe-labeled house crickets with refined maize porridge (3.06%) and from refined maize porridge with unlabeled crickets (4.92%) was lower than from the reference meal (14.2%), with respective mean differences of −11.1% (95% CI: −12.6%, −9.68%) and −9.29% (95% CI: −10.8%, −7.77%). Iron absorption from all meals based on unrefined maize porridge was low (<3%), and did not differ for the 2 meals with crickets compared with the reference meal. In vitro digestion showed that chitin, chitosan, and calcium limited iron bioaccessibility to a large extent. Conclusions Iron absorption from house crickets and fortified maize porridge with crickets is low, which may be explained by the presence of chitin and other inhibitors in the cricket biomass.ISSN:0002-9165ISSN:1938-320