ABSTRACT
This research synthesized structure lipids (SL) from blends of fully hydrogenated palm kernel oil (FHPKO), coconut oil (CNO) and fully hydrogenated palm stearin (FHPS) by enzymatic interesterification (EIE)using rProROL, an sn-1,3-specific lipase from Rhizopus oryzae, as a catalyst. Five physical blends of FHPKO:CNO:FHPS were prepared with the following wt. ratios: 40:10:50, 50:10:40, 60:10:30, 70:10:20 and 80:10:10. The EIE reactions were carried out at 60â for 6 h in a batch-type reactor using rProROL 10% wt. of the substrate. It was found that EIE significantly modified the triacylglycerol compositions of the fat blends resulting in changes in the crystallization and melting behavior. In particular, SL obtained from EIE of blend 70:10:20 exhibited high potential to be used as a cocoa butter substitute (CBS) because it showed similar solid fat content curve to the commercial CBS and crystallized into fine spherulites and desirable ß' polymorph.
Subject(s)
Plant Oils , Coconut Oil/chemistry , Dietary Fats , Esterification , Palm Oil/chemistry , Plant Oils/chemistry , TriglyceridesABSTRACT
BACKGROUND: Chemical interesterification (CIE) is one of the important technological processes for the production of zero-trans fats. The aim of this study was to produce trans-free cocoa butter alternatives (CBAs) from palm kernel stearin (PKS), coconut oil (CNO) and fully-hydrogenated palm stearin (FHPS) blends via CIE using sodium methoxide as a catalyst. The physicochemical properties, crystallization and melting behavior, solid fat content (SFC), crystal morphology and polymorphism of the structured lipids (SLs) obtained and the corresponding physical blends (PBs) were characterized and compared with commercial CBAs. RESULTS: After CIE, randomization of fatty acid distribution within and among triacylglycerol (TAG) molecules of PKS, CNO and FHPS resulted in a modification in TAG compositions of the PKS/CNO/FHPS blends and improved the properties and crystallization behavior of the blends. SFC and slip melting points of all SLs decreased from those of their respective PBs. In particular, SLs obtained from CIE of blends with 60-70% wt. PKS (blend ratios 60:10:30 and 70:10:20) exhibited the melting characteristic, SFC curves, crystal morphology and polymorphic form most similar to the commercial CBAs. In addition, these blends melted almost completely at body temperature, an improvement from that of the commercial CBAs. CONCLUSION: SLs obtained from CIE of blends with 60-70% wt. PKS has high potential to be used commercially as trans-free CBAs for the confectionery industry. © 2021 Society of Chemical Industry.
Subject(s)
Plant Oils , Coconut Oil , Dietary Fats , Esterification , Palm Oil , TriglyceridesABSTRACT
Lauric fat cocoa butter replacer (LCBR) was produced from a blend of krabok seed fat (KSF) and coconut oil (CO). Four fat blends with different ratios of KSF/CO (20/80, 40/60, 60/40 and 80/20 (%wt)), CO, KSF and a commercial LCBR (C-LCBR) were characterized using various techniques. It was found that blend 60/40 exhibited SFC curve and crystallization/melting behavior most similar to that of C-LCBR. The blend met the requirements to be considered as LCBR and has potential as an alternative to commercial LCBR that are being used nowadays and hence it was recommended as LCBR (called R-LCBR). The polymorphic behavior of both C-LCBR and R-LCBR was investigated and both fats displayed mainly short spacing pattern associated with ß' polymorph, a required polymorph for LCBR. The compatibility between R-LCBR and CB was investigated by mixing the R-LCBR with CB in different proportions and softening due to the eutectic effect was observed in the mixed fats. This limits the proportion of CB and the R-LCBR in compound coatings to no more than 5% of CB in the total fat phase.