Do cooking techniques influence copper bioaccesibility in foods after in vitro digestion/fermentation in adults and children?

[Display omitted] •In raw/cooked foods, Cu bioaccessibility (Cu-BA) in the small intestine is higher.•Cooking techniques influence Cu-BA depending on the food group.•In vegetables, the most drastic cooking techniques show higher total Cu-BA.•The Cu-BA is higher in raw, whole grains and cereals with gluten.•In infancy, Cu-BA is higher than in adulthood and celiac disease, obesity, allergy. Cu is essential for the growth and organism health. Classically, its available fraction has been studied by in vitro digestion studies as a measure of bioaccessibility of Cu (Cu-BA). In this work we applied a novel in vitro digestion/fermentation method to multiple foods subjected to different home cooking techniques (raw form vs. frying, roasting, toasting, boiling and grilling) by metabolization with faecal inoculate from healthy adults (HE-AD), and healthy children (HE-CH) and sick children (children with gluten related disorders, GRD-CH; children with obesity, OB-CH; and children with allergy/intolerance to cow’s milk proteins, AICM-CH). In raw and cooked foods the bioaccessibility of Cu in the small intestine (Cu-BASI) was higher vs. that in the Cu bioaccessibility in the large intestine (Cu-BALI) (30.8 ± 15.4 and 28.2 ± 14.7 vs. 18.4 ± 21.2 and 22.8 ± 22.1 %, respectively; p