Cold Sterilization of Coconut Water Using Membrane Filtration: Effect of Membrane Property and Operating Condition

Authors

  • A. Laorko Department of Food Technology, Faculty of Agro–Industry
  • Z. Li Membrane Science and Technology Research Center, Prince of Songkla University Hat Yai, Songkhla, 90112, Thailand
  • W. Youravong Membrane Science and Technology Research Center, Prince of Songkla University Hat Yai, Songkhla, 90112, Thailand
  • S. Tongjitpakdee Department of Food science and Technology, Faculty of Agro–Industry, Kasetsart University, Bangkok, 10900, Thailand
  • S. Chantachum Department of Food Technology, Faculty of Agro–Industry

DOI:

https://doi.org/10.11113/amst.v7i1.56

Abstract

Coconut water has been considered as a nutritional, refreshing and highly isotonic beverage with delicate aroma and flavor. In food sterilization technique, thermal processing, however tends to reduce these beneficial properties especially estrogen hormone and flavor. To overcome this limitation, this study therefore aimed to clarified and sterilized coconut water using non–thermal processing, membrane filtration. Hollow fiber microfiltration (MF) membrane with pore size of 0.1 and 0.2 μm and ultrafiltration (UF) membrane with molecular weight cut–off (MWCO) of 100 and 30 kDa were used. The effect of membrane pore size and MWCO on quality of clarified juice, permeate flux and fouling were studied. It was found that fresh coconut water and clarified coconut water obtained from MF and UF did not show difference in pH, total soluble solid, reducing sugar, estrogen hormone and minerals including calcium, magnesium, phosphorus, potassium and sodium. The results from microbiological analysis of the clarified coconut water showed that sterilized of coconut water was obtained using either MF or UF membranes. This microbiological quality of clarified coconut water was met the Thai legislation for juice and drinks. The permeate flux of MF was much higher than those of UF while the fouling resistance of UF membrane was much higher than those of MF membrane. The permeate flux of membrane with pore size of 0.1 £gm was slightly lower than that of membrane with pore size of 0.2 μm. The results also indicated that the major fouling of both MF and UF membranes was reversible. The irreversible fouling resistance of 0.1 μm membrane was the lowest and most of this irreversible fouling was external irreversible fouling, formed on the membrane surface. According to these results, it could be concluded that 0.1 μm membrane was the most suitable membrane for clarification and sterilization of coconut water. In addition, the effects of TMP, cross flow velocity (CFV) and the % recovery on permeate flux in batch concentration mode were also studied. It was found that the permeate flux of 0.1 μm membrane was significantly increased with increasing CFV and decreased as % recovery increased. These results suggested that permeate flux during MF of coconut water was dependent on reversible fouling and could be improved by using hydrodynamic modification techniques.

Downloads

Published

2017-11-20

How to Cite

Laorko, A., Li, Z., Youravong, W., Tongjitpakdee, S., & Chantachum, S. (2017). Cold Sterilization of Coconut Water Using Membrane Filtration: Effect of Membrane Property and Operating Condition. Journal of Applied Membrane Science &Amp; Technology, 7(1). https://doi.org/10.11113/amst.v7i1.56

Issue

Section

Articles