Cold Pasteurization Of Tender Coconut Water By A Batch And Flow Processes Using Glassbeads Coated With Phytochemicals Encapsulated Nano-Liposomes

Author

Jim Thomson, Southern Illinois University CarbondaleFollow

Date of Award

5-1-2018

Degree Name

Master of Science

Department

Plant and Soil Science

First Advisor

Choudhary, Ruplal

Abstract

Tender coconut water (TCW) is one of most consumed natural energy drinks. Although it is widely available in tropical countries, because of its natural health benefits it is increasingly consumed in other parts of the world. Therefore there has been an increased requirement for packaging and shipping. TCW is highly susceptible to microbial contamination during extraction and packaging, requiring pasteurization. Thermal pasteurization leads to loss of flavor and color of coconut water. The purpose of this study was to test the feasibility of a non-thermal method of pasteurization of TCW using natural antimicrobials like curcumin, eugenol, and d-limonene with curcumin. The non-thermal pasteurization method was developed in two different processes, i.e. a batch and flow-filter process. Batch cold pasteurization process was conducted by suspending liposome encapsulated antimicrobials immobilized on glassbeads in TCW at 4oC by shake flask assay. Maximum Reduction of Listeria monocytogenes and Escherichia coli W1485 in pasteurized TCW were observed to be 5 log CFU per ml of TCW within 7 days of incubation under the presence of nano-liposomes containing 50 mM of curcumin, d- limonene or eugenol. There was no change in color and aroma of TCW after 1 month of storage at 4oC. the flow filter cold pasteurization process was developed using filter medium coated with nano-liposomes encapsulated antimicrobial leading to extended release of the natural antimicrobial curcumin to the coconut water in 4oC. Listeria monocytogenes and E. coli W1485 were used as model organisms to test effectiveness of cold pasteurization. Reduction of L. monocytogenes and E. coli W1485 in pasteurized TCW was observed to be 5.2 and 4.5 log10CFU/ml of TCW respectively within 17.25 min of incubation under the presence of nano-liposomes containing 50 mM of curcumin. There was no change in color and aroma of TCW after 1 week of storage at 4oC.