title: trans-C18:1 isomers in cheeses enriched in unsaturated fatty acids and manufactured with different milk fat globule sizes.
abstract: Increasing the knowledge on dietary fat composition, mainly the minor components, will improve the nutritional value of foods and their labeling. In this study, we examined the trans-octadecenoic acid (C18:1) composition of Emmental cheeses enriched in unsaturated fatty acids (FA) and manufactured with milks produced by cows selected to produce small and large fat globules. The FA composition of the milks was not significantly ( P > 0.05) different from the FA composition of the corresponding Emmental cheeses. Increasing the unsaturated FA content of the cheeses using dietary manipulations lead to an increase in the trans-C18:1 and changed their isomeric profiles. In milk fat produced with the linseed-enriched diet, the trans-10 C18:1 concentration was greater than trans-11 C18:1 (vaccenic acid), which is classically the major trans-C18:1 in milk fat. The content in trans-C18:1 and more particularly in trans-10 C18:1 was negatively correlated with the size of fat globules ( r (2) = 0. 82 and 0.87, respectively) and related to milk fat depression. The trans-C18:1 content was negatively correlated with the saturated FA (slope = -0.35; r (2) = 0.81) and positively correlated with the unsaturated (slope = 0.29; r (2) = 0.85) and monounsaturated (slope = 0.32; r (2) = 0.81) FA. Focusing on the health-related considerations of fat in food products, further nutritional studies are needed to elucidate the role of trans-C18:1 isomers.
authors.affiliation: INRA, UMR1253 Science et Technologie du Lait et de l'oeuf, F-35042 Rennes, France.
authors.forename: Valerie
authors.initials: V
authors.lastname: Briard-Bion
authors.forename: Pierre
authors.initials: P
authors.lastname: Juaneda
authors.forename: Romain
authors.initials: R
authors.lastname: Richoux
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Guichard
authors.forename: Christelle
authors.initials: C
authors.lastname: Lopez
mesh_terms: D000821:Animal Feed / Q000032:analysis; D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D002417:Cattle; D002611:Cheese / Q000032:analysis*; D005231:Fatty Acids, Unsaturated / Q000737:chemistry*; D005260:Female; D006017:Glycolipids / Q000737:chemistry*; D006023:Glycoproteins / Q000737:chemistry*; D007774:Lactation; D066292:Lipid Droplets; D008892:Milk / Q000737:chemistry*; D013229:Stearic Acids / Q000737:chemistry*; D044242:Trans Fatty Acids / Q000737:chemistry*
chemical_list: C114874:5-octadecenoic acid; D005231:Fatty Acids, Unsaturated; D006017:Glycolipids; D006023:Glycoproteins; D013229:Stearic Acids; D044242:Trans Fatty Acids; C110367:milk fat globule