title: Effects of the heating process of soybean oil and seeds on fatty acid biohydrogenation in vitro.
abstract: Heating fat is an efficient way to alter ruminal biohydrogenation (BH) and milk fat quality. Nevertheless, results are variable among studies and this could be due to various heating conditions differently affecting BH. The objectives of this study were to determine the effect of type and duration of heating of soybean oil or seeds on BH in vitro. Ruminal content cultures were incubated to first investigate the effects of roasting duration (no heating, and 0.5- and 6-h roasting) at 125°C and its interaction with fat source (soybean seeds vs. soybean oil), focusing on linoleic acid BH and its intermediates: conjugated linoleic acid (CLA) and trans-C18:1. Additionally, we compared the effects of seed extrusion with the 6 combinations of unheated and roasted oils and seeds. None of the treatments was efficient to protect linoleic acid from BH. Soybean oil resulted in higher trans-11 isomer production than seeds: 5.7 and 1.2 times higher for cis-9,trans-11 CLA and trans-11 C18:1, respectively. A 125°C, 0.5-h roasting increased trans-11 isomer production by 11% compared with no heating and 6-h roasted fat. Extrusion of seeds was more efficient to increase trans-11 C18:1 production than seed roasting, leading to values similar to oils. For other fatty acids, including cis-9,trans-11 CLA, extrusion resulted in similar balances to seeds (mainly 0.5-h-roasted seeds). Extruded oilseeds would be more efficient than roasted seeds to produce trans-11 C18:1; nevertheless, effects of conditions of extrusion need to be explored.
authors.affiliation: Université de Toulouse INPT ENVT, UMR1289 Tissus Animaux Nutrition Digestion Ecosystème et Métabolisme, F-31076 Toulouse, France; INRA, UMR1289 Tissus Animaux Nutrition Digestion Ecosystème et Métabolisme, F-31326 Castanet-Tolosan, France; Université de Toulouse INPT ENSAT, UMR1289 Tissus Animaux Nutrition Digestion Ecosystème et Métabolisme, F-31326 Castanet-Tolosan, France. Electronic address: a.troegeler@envt.fr.
authors.forename: A
authors.initials: A
authors.lastname: Troegeler-Meynadier
authors.affiliation: Université de Toulouse INPT ENVT, UMR1289 Tissus Animaux Nutrition Digestion Ecosystème et Métabolisme, F-31076 Toulouse, France; INRA, UMR1289 Tissus Animaux Nutrition Digestion Ecosystème et Métabolisme, F-31326 Castanet-Tolosan, France; Université de Toulouse INPT ENSAT, UMR1289 Tissus Animaux Nutrition Digestion Ecosystème et Métabolisme, F-31326 Castanet-Tolosan, France.
authors.forename: S
authors.initials: S
authors.lastname: Puaut
authors.affiliation: Université de Toulouse INPT ENVT, UMR1289 Tissus Animaux Nutrition Digestion Ecosystème et Métabolisme, F-31076 Toulouse, France; INRA, UMR1289 Tissus Animaux Nutrition Digestion Ecosystème et Métabolisme, F-31326 Castanet-Tolosan, France; Université de Toulouse INPT ENSAT, UMR1289 Tissus Animaux Nutrition Digestion Ecosystème et Métabolisme, F-31326 Castanet-Tolosan, France.
authors.forename: Y
authors.initials: Y
authors.lastname: Farizon
authors.affiliation: Université de Toulouse INPT ENVT, UMR1289 Tissus Animaux Nutrition Digestion Ecosystème et Métabolisme, F-31076 Toulouse, France; INRA, UMR1289 Tissus Animaux Nutrition Digestion Ecosystème et Métabolisme, F-31326 Castanet-Tolosan, France; Université de Toulouse INPT ENSAT, UMR1289 Tissus Animaux Nutrition Digestion Ecosystème et Métabolisme, F-31326 Castanet-Tolosan, France.
authors.forename: F
authors.initials: F
authors.lastname: Enjalbert
mesh_terms: D000818:Animals; D005227:Fatty Acids / Q000737:chemistry*; D005511:Food Handling / Q000379:methods*; D006361:Heating; D006358:Hot Temperature; D006865:Hydrogenation; D019787:Linoleic Acid / Q000737:chemistry; D044243:Linoleic Acids, Conjugated / Q000737:chemistry; D012417:Rumen; D012639:Seeds / Q000737:chemistry*; D013024:Soybean Oil / Q000737:chemistry*
chemical_list: D005227:Fatty Acids; D044243:Linoleic Acids, Conjugated; D013024:Soybean Oil; D019787:Linoleic Acid
keywords: extrusion; roasting; ruminal biohydrogenation; trans fatty acid