Folate contents in insects as promising food components quantified by stable isotope dilution

Concerning the increasing population, edible insects are of growing interest due to several advantages such as sustainable production and as a source of high-quality nutrients. One of the less studied nutrients are folates, in the context of insects is folates, which play an important role in human metabolism. In the article, we describe how six different insect species are reared and extracted for five common folate vitamers by high-performance liquid chromatography interfaced with tandem mass spectrometry (LC-MS/MS). For this purpose, house crickets (Acheta domesticus—adults), Jamaican field crickets (Gryllus assimilis—adults), discoid cockroaches (Blaberus discoidalis—nymphs), migratory locusts (Locusta migratoria—adults), mealworms (Tenebrio molitor), and lesser mealworms (Alphitobius diaperinus) were investigated. The total folate content differs between 59.1 ± 6.50 and 143 ± 11.1 μg/100 g. Also, the feed, which was adapted to the needs of the insects and differed for some species, was extracted for their total folate content. The four different feed compositions (rapeseed, chicken feed, bramble leaves, and a mix of chicken feed, wheat bran, and carrot/apples) showed a folate content of about 100 μg/100 g, except for hay, where the content was 300 μg/100 g. In general, the insect folate content is comparable to other food and seems to be a promising source of folates. However, the amount of consumption needed to meet the requirement must also be considered. Moreover, the effect of different influencing factors is not yet entirely clear and needs further investigation.