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

Yee Ying Lee, Teck Kim Tang, Eng Tong Phuah, Nur Azwani Ab Karim, Siti Maslina Mohd Alwi, Oi Ming Lai

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23 Citations (Scopus)

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 (R2 = 0.9979) and by-products (R2 = 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.

Original languageEnglish
Pages (from-to)685-696
Number of pages12
JournalJournal of Food Science and Technology
Volume52
Issue number2
DOIs
Publication statusPublished - Feb 2013
Externally publishedYes

Keywords

  • Interesterification
  • Medium-and long-chain triacylglycerol (MLCT)
  • Palm kernel oil
  • Palm oil
  • Response surface methodology (RSM)
  • TLIM lipase

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