Contamination of Fecal Coliform and Staphylococcus sp. on Green Grass Jelly (Premna oblong;folia Merr) in Bogor and Effect of Steaming on Microbiological and Physical Properties of the Product

Abstract

Green grass jelly is one of potential functional food due to its content of bioactive compounds such as flavonoids and chlorophyll. Despite its health benefit, the safety of the products is of concern since the production process is susceptible to microbial contamination . Microbiological analysis of 14 samples of green grass jelly in Bogor showed that the samples contained aerobic plate count between 1.6 x 104 to 2.4 X 106 CFU/g, fecal coliform 3.0 x 102 to 4.4 X 103 CFU/g, and Staphylococcus sp. 2.5 x 101 to 2.0 X 103 CFU/g, hence indicating a high level of microbial contamination during processing and marketing of the products. Steaming treatment effectively reduced the aerobic plate count up to 1.10 log CFU/g, fecal coliform 1.18 log CFU/g, and Staph ylococcus sp. 0.71 log CFU/g. However, the physical characteristics of green grass jelly were adversely affected by steaming treatment. The color of the jelly was changed from its original dark green to brownish green. Steaming treatment also slightly increased the green grass jelly syneresis (9 .03%) and decreased the gel strength {2.99 g/cm\ The results indicated the prospective use of thermal in improving microbiological quality and safety of green grass jelly. Yet, further study on thermal design and application on green grass jelly is essential to achieve optimal microbiological properties while preserving favorable physical and sensory characteristics of the product