Palm-based medium-and-long-chain triacylglycerol (P-MLCT): production via enzymatic interesterification and optimization using response surface methodology (RSM)

Abstract

Structured lipid such as medium-and long-chain triacylglycerol (MLCT) is claimed to be able to suppress body fat accumulation and be used to manage obesity. Response surface methodology (RSM) with four factors and three levels (+1,0,-1) faced centered composite design (FCCD) was employed for optimization of the enzymatic interesterification conditions of palm-based MLCT (P-MLCT) production. The effect of the four variables namely: substrate ratio palm kernel oil: palm oil, PKO:PO (40:60-100:0 w/w), temperature (50-70 °C), reaction time (0.5-7.5 h) and enzyme load (5-15 % w/w) on the P-MLCT yield (%) and by products (%) produced were investigated. The responses were determined via acylglycerol composition obtained from high performance liquid chromatography. Well-fitted models were successfully established for both responses: P-MLCT yield (R (2) = 0.9979) and by-products (R (2) = 0.9892). The P-MLCT yield was significantly (P < 0.05) affected by substrate ratio, reaction time and reaction temperature but not enzyme load (P > 0.05). Substrate ratio PKO: PO (100:0 w/w) gave the highest yield of P-MLCT (61 %). Nonetheless, substrate ratio of PKO: PO (90:10w/w) was chosen to improve the fatty acid composition of the P-MLCT. The optimized conditions for substrate ratio PKO: PO (90:10 w/w) was 7.26 h, 50 °C and 5 % (w/w) Lipozyme TLIM lipase, which managed to give 60 % yields of P-MLCT. Up scaled results in stirred tank batch reactor gave similar yields as lab scale. A 20 % increase in P-MLCT yield was obtained via RSM. The effect of enzymatic interesterification on the physicochemical properties of PKO:PO (90:10 w/w) were also studied. Thermoprofile showed that the P-MLCT oil melted below body temperature of 37 °C.

Response surface methodology to optimize enzyme-assisted aqueous extraction of maize germ oil

“…The oil phase floating at the top was collected using a pipette and transferred to a beaker. Residue of the slurry was used for estimation of proximate composition (Latif 2009;Olaniyan 2007). The oil was placed in a hot air oven at a temperature of 70°C for 30 min to remove the residual water present in the oil.…”

“…Optimization is done in order to improve the efficiency of the system in terms of performance, product yield and cost. The numerical optimization has been done using response surface methodology (Lee et al 2015;Mishra et al 2015). In this study, we show that appropriate choice of the enzyme(s) and optimization of extraction conditions make it possible to improve the oil recovery from maize germ of a PMH 1 variety using enzyme-assisted aqueous oil extraction method.…”

“…In EAAE process, the enzymes improve oil recovery by degrading the seed cell wall, resulting in rupturing the polysaccharide-protein colloid system (Latif 2009). The percent oil yield from maize germ varied from 36.71 to 88.58 %.…”

“…In 2001, the US Environmental Protection Agency issued stricter guidelines for hexane emissions by vegetable oil extraction facilities (EPA 2001), providing new incentives to develop alternative methods of edible oil extraction. A number of aqueous (Rhee et al 1972;Shi et al 1998), aqueous enzymatic (Bocevska et al 1993;Karlovic et al 1994;Latif 2009) and enzyme-assisted solvent extraction (Owusu-Ansah 1997) methods have been developed, but the current consensus is that hexane extraction is still much less expensive than any of these alternative approaches. Enzyme assisted aqueous oil extraction has emerged as an eco-friendly process for oil extraction (Mcglone et al 1986;Bocevska et al 1993) and this method could reduces the breakage for the functional component of oil (Qian et al 2011).…”

Enzymatic Interesterification of Lauric Fat Blends Formulated by Grouping Triacylglycerol Melting Points

“…The interesterified lauric fat blends may thus contain MCFA and LCFA on the same glycerol backbone and are known as MLCT (medium-and long-chain triacylglycerols) [17]. Intake of products containing MLCT has been reported to be able to suppress body fat accumulation over long periods of time [18,19]. Lipase-catalyzed interesterification can be random or regioselective.…”