Shelf life assessment of natural antioxidant-treated milk smoothies stored under refrigeration at 4 ± 2^°C

Abstract

Purpose

This paper aims to assess the effect of natural antioxidants (Tulsi, Lemon grass and Aloevera) on sensory and microbiological quality as well as on Thiobarbituric acid (TBA) values of Redplum and Sahiwal-based milk smoothies stored under refrigeration.

Design/methodology/approach

The smoothies were developed by incorporating optimum level of natural antioxidants, fresh red plum and Sahiwal milk. They were aerobically packaged in low-density polyethylene pouches and stored under refrigeration (4 ± 2°C) till its spoilage. These smoothies were assessed for various storage quality parameters like sensory parameters, microbiological quality and TBA values at regular interval of two days.

Findings

Smoothies made without using natural antioxidants were in good condition for four days, and treated smoothies were stored well for six days. The microbial profile showed significant (p < 0.05) increase in SPC and psychrophilic counts on advancement of storage days. However, no coliform and yeast and mould were detected in all variants of smoothies during storage. TBA values were also increased during storage. But microbial counts and TBA both were under the prescribed limit as described by various organizations. Smoothies treated with Tulsi were found best followed by lemongrass- and aloevera-treated products.

Research limitations/implications

Amino acid and fatty acid profiling may be incorporated to known how the exact nutritional value.

Practical implications

Developed milk smoothies using natural antioxidants may serve the purpose of functional food.

Social implications

As per the authors, today, world is seeking for health providing components with longer product shelf life. Therefore, the product may serve the purpose.

Originality/value

The paper has demonstrated that the Sahiwal milk and red plum-based smoothies were of high acceptability. Their shelf life was found best when treated with Tulsi, Lemon grass and Aloevera natural antioxidants. It was better in all spectrums like lower microbial counts, higher sensory attributes and lower TBA counts as compared to untreated products.

Citation

Kumar, B., Singh, V.P., Pathak, V. and Verma, A.K. (2019), "Shelf life assessment of natural antioxidant-treated milk smoothies stored under refrigeration at 4 ± 2^°C", Nutrition & Food Science, Vol. 49 No. 6, pp. 1000-1013. https://doi.org/10.1108/NFS-10-2018-0291