The antimicrobial and shelf-life study of vegetable sanitizer from herbal extracts and Acacia concinna(Willd.) D.C’s pod water

Abstract

In the past 3 years, the Centers for Disease Control and Prevention (CDC) reported that there were at least 7 outbreaks in fresh produces, for example; Escherichia coli O121 in raw clover sprouts (2014), E. coli O157:H7 in ready-to-eat salads (2013), and Salmonella Saintpaul in cucumbers (2013). The cleaning of fresh produces is the first step in order to prevent foodborne outbreak. Therefore, this experiment aims to study and develop the shelf life of vegetable sanitizer from Thai herb crude extracts including Cymbopogon citratus (Lemongrass), Citrus hystrix (Kaffir lime), Chrysanthemum indicum (Chrysanthemum) and Acacia concinna (Willd.) D.C’s pod (Som-poi) water compared with 2 commercial brands namely Jirada and Veggie. To achieve this goal, antibacterial activity and shelf-life study were determined by antimicrobial efficiency experiment using total plate count. In this study, the vegetable sanitizer was prepared by adding 1.5% of each 0.2 g/ml crude extracts into Som-poi’s pod water and then sterilized at 121 ºC for 15 minutes. Lactuca sativa (Lettuce) using as vegetable model was soaked in 1 % of the vegetable sanitizer in water for 20 minutes before determination antibacterial activity of the vegetable sanitizer every 2 weeks for 10 weeks. Surprisingly, the results showed that the highest percentage of antimicrobial efficiency was 99.70±0.13. Although the percentage of antimicrobial efficiency decreased significantly after the 6th week; however, antimicrobial efficiency of the vegetable sanitizer remained higher than 90% up to 10 weeks. There was no significant difference of antimicrobial efficiency among 2 commercial brands and the vegetable sanitizer for 8 weeks. In conclusion, the results illustrated hat the vegetable sanitizer from Thai herbal extracts and A. concinna (Willd.) D.C’s pod water was excellent in antibacterial activity as well as a commercial brand however it could be more value in terms of a green vegetable sanitizer.