Enrichment of anhydrous milk fat in polyunsaturated fatty acid residues from linseed and rapeseed oils through enzymatic interesterification.
Lipozyme TL IM was used in a solvent-free batch and microaqueous system for enzymatic interesterification of anhydrous milkfat (AMF) with linseed oil (LO) in binary blends and with rapeseed oil (RO) in one ternary blend. The aim was to obtain and characterize physicochemically fats enriched with unsaturated C 18 fatty acids (oleic, linoleic, and, especially, linolenic acids) from natural vegetable oils. Binary blends of AMF/LO 100/0, 90/10, 80/20, 70/30, and 60/40 (w/w) were interesterified. The change in triacylglycerol (TAG) profiles showed that quasi-equilibrium conditions were reached after 4-6 h of reaction. Free fatty acid contents <1%. The decrease in solid fat content and in dropping point temperature obtained with increasing content of LO and interesterification resulted in good plastic properties for the products originating from the blends 70/30 and 60/40. This was confirmed by textural measurements. Melting profiles determined by differential scanning calorimetry showed complete disappearance of low-melting TAGs from LO and the formation of intermediary species with a lower melting temperature. Oxidative stability of the interesterified products was diminished with increasing LO content, resulting in low oxidation induction times. A ternary blend composed of AMF/RO/LO 70/20/10 gave satisfactory rheological and oxidative properties, fulfilling the requirements for a marketable spread and, moreover, offering increased potential health benefits due to the enriched content in polyunsaturated fatty acid residues.
Aguedo
Mario
M
Laboratory of General and Organic Chemistry, Department of Chemistry and Bio-Industries, Gembloux Agricultural University (FUSAGx), Passage des Déportés 2, B-5030 Gembloux, Belgium.
Hanon
Emilien
E
Danthine
Sabine
S
Paquot
Michel
M
Lognay
Georges
G
Thomas
Annick
A
Vandenbol
Micheline
M
Thonart
Philippe
P
Wathelet
Jean-Paul
JP
Blecker
Christophe
C
D000818:Animals; D002152:Calorimetry, Differential Scanning; D004951:Esterification; D005229:Fatty Acids, Monounsaturated; D005231:Fatty Acids, Unsaturated / Q000032:analysis*; D006801:Humans; D008043:Linseed Oil / Q000737:chemistry*; D008049:Lipase / Q000378:metabolism*; D008892:Milk / Q000737:chemistry*; D010084:Oxidation-Reduction; D010938:Plant Oils / Q000737:chemistry*; D000074262:Rapeseed Oil; D012212:Rheology; D013696:Temperature; D014280:Triglycerides / Q000032:analysis / Q000378:metabolism*
D005229:Fatty Acids, Monounsaturated; D005231:Fatty Acids, Unsaturated; D010938:Plant Oils; D000074262:Rapeseed Oil; D014280:Triglycerides; D008043:Linseed Oil; C093666:Lipozyme; D008049:Lipase