Effect of packaging materials and storage temperature on the physicochemical and microbial properties of ultrasonicated mature coconut water during storage

Preservation and shelf life extension of mature coconut water (MCW) is paramount importance for the pro-duction of flavored beverages. The present study aims to evaluates the effects of packaging materials (glass bottles, PET bottles and stand-up pouches) and storage temperatures such as atmospheric (28 +/- 6 degrees C) and cold storage (5 +/- 1 degrees C) temperatures on microbial growth and quality parameters (pH, Total Soluble Solids (TSS), total sugar, reducing sugar, and non-reducing sugar) of ultrasound treated MCW during storage. The results showed that pH, total soluble solids, total sugar, reducing sugar and non-reducing sugars decreased significantly (p < 0.05) during storage, irrespective of packaging materials. It was observed that the microbial load increased significantly (p < 0.05) during storage of ultrasonicated samples and control samples. The present study concluded that ultrasonication of MCW at 60% amplitude for 10 min treatment time increased their shelf life up to 12 days under cold storage condition (5 +/- 2 degrees C) with a safe limit of microbial load and maximum retention of nutrients. Even though all the packaging materials were found to be statistically on par (p > 0.05) in maintaining quality parameters and microbial load, glass bottles were observed to be most effective packaging followed by PET bottles and stand-up pouches.