Shelf-life Extension of Spring Roll Wrappers Using Acidification Combined with Sodium Benzoate Addition
Sunisa Suwannaphan*
and Ploy Klangmuang
Department of Food Science and Technology, Faculty of Agricultural Technology and Agro-Industry, Rajamangala University of Technology Suvarnabhumi, Phra Nakhon Si Ayutthaya, Thailand.
Corresponding Author Email: sns_mai@hotmail.com
Abstract:
At ambient temperature, spring roll wrappers used for roti saimai are highly perishable. Adding organic acids such as 0-0.6% citric acid or vinegar (acetic acid) was evaluated for wrapper pH and sensory acceptability. The Addition of 0.4% citric acid or 0.5% vinegar to spring roll wrappers reduced pH below 4.5 and proved acceptable for panelists. Spring roll wrappers treated with 0.4% citric acid or 0.5% vinegar with/without 0.06% sodium benzoate were packed in two bag types (polypropylene; PP and nylon-linear low density polyethylene; nylon-LLDPE) and stored at ambient and refrigerated temperatures to investigate microbial loads. Vinegar had a greater antimicrobial effect than citric acid, while microbial reduction efficacy increased through the synergistic effects of vinegar and sodium benzoate. Spring roll wrappers treated with 0.5% vinegar with/without 0.06% sodium benzoate were selected to assess changes in quality and shelf-life. Results showed no significant differences in thickness and water activity (aw) values among all conditions. Nylon-LLDPE bags maintained spring roll wrapper moisture content better than PP bags but spring roll wrappers packed in nylon-LLDPE cracked more rapidly than those packed in PP bags during storage at refrigerated temperature. Sodium benzoate also decreased spring roll wrapper springiness. Spring roll wrappers treated with 0.5% vinegar and 0.06% sodium benzoate proved an optimal when packed in PP and nylon-LLDPE bags after storage at refrigerated and ambient temperatures, with shelf-lives of 7 and 13 days respectively.
Keywords:
Organic Acid; Roti Saimai; Spring Roll Wrapper; Sodium Benzoate; Shelf-Life
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