title: Effect of heat treatment on the biological value of beta-carotene added to soybean cooking oil in rats.
abstract: Vitamin A deficiency is one of the major nutritional problems in the world, most common in developing countries. Food fortification is a recognised approach to supply vitamins and minerals to needed populations. Vegetable cooking oils were previously suggested by us as a carrier for vitamin A fortification. Fortification of cooking oil with beta-carotene could also be a strategy to prevent vitamin A deficiency. The objective of this article is to start studies on the use of cooking soya oil as a vehicle for synthetic carotene, to evaluate its stability to heat treatment, and to test its bioavailability and bioconversion to vitamin A in rats. Batches of carotene-fortified soybean oil were prepared, containing 2, 4 and 8 RE/g of diet. Some of them were heated to test its stability. At 100 degrees C there was no loss of carotene, at higher temperature carotene retention was 65%. The bioavailability and bioconversion of beta-carotene added to soybean oil was measured through feeding nursing rats and their pups method. Weight gain was good and plasma vitamin A increased significantly in all groups. Liver vitamin A values of rats fed diets with fortified soybean oil heated at 100 degrees C was similar to the 4 RE non-heated fortified oil group (0.72 +/- 0.06 and 0.64 +/- 0.08 mumol/g, respectively). Heated at 170 degrees C the liver total vitamin A value was reduced (0.45 +/- 0.04 mumol/g), but kept bioavailable vitamin A equivalent to 2 RE (0.47 +/- 0.09 mumol/g). Bioconversion of beta-carotene to vitamin A was validated by the plasma and liver findings. beta-carotene added to soybean oil showed good stability to heat and its bioconversion to vitamin A was shown in rat assays. beta-carotene mixed well with edible soybean oil and the fortified cooking oil showed potential as a carrier to be used for the prevention of vitamin A deficiency.
authors.affiliation: Department of Internal Medicine-Nutrition Division, Faculty of Medicine of Ribeirão Preto, University of São Paulo, Brazil.
authors.forename: J E
authors.initials: JE
authors.lastname: Dutra-de-Oliveira
authors.forename: R M
authors.initials: RM
authors.lastname: Fávaro
authors.forename: M V
authors.initials: MV
authors.lastname: Junqueira-Franco
authors.forename: C G
authors.initials: CG
authors.lastname: Carvalho
authors.forename: A A
authors.initials: AA
authors.lastname: Jordão Júnior
authors.forename: H
authors.initials: H
authors.lastname: Vannucchi
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001682:Biological Availability; D004042:Dietary Fats, Unsaturated; D005260:Female; D005527:Food, Fortified; D006358:Hot Temperature; D008099:Liver / Q000737:chemistry; D009753:Nutritive Value; D051381:Rats; D017208:Rats, Wistar; D013024:Soybean Oil; D014801:Vitamin A / Q000032:analysis / Q000097:blood; D014802:Vitamin A Deficiency / Q000178:diet therapy*; D019207:beta Carotene / Q000378:metabolism / Q000493:pharmacokinetics*
chemical_list: D004042:Dietary Fats, Unsaturated; D019207:beta Carotene; D014801:Vitamin A; D013024:Soybean Oil