Potential safe handling practice for shredded turnip

3 Sep 2015 NUS food scientists have identified safe handling practice and storage conditions for shredded turnips in collaboration with the Agri-Food and Veterinary Authority (AVA).

Shredded turnip is a popular ingredient of yusheng salad savored during the Chinese New Year. However, fresh-cut turnip is not commercially produced in the region due to its perishable nature.

A team led by Prof YUK Hyun-Gyun from the Food Science & Technology Programme in the Department of Chemistry, NUS has studied the effectiveness of six sanitizers including acid electrolyzed water (AcEW), acidified sodium chlorite (ASC), cetylpyridinium chloride (CPC), chlorine, ozonated water and sodium dichloroisocyanurate (NaDCC) against natural microflora and inoculated Salmonella spp. on peeled turnips. ASC treatment was the most effective in reducing the counts of aerobic mesophiles, yeasts and molds and Salmonella spp. (see Figure). Subsequent storage study indicated that shredded ASC-treated turnip stored in aerobic conditions at 4°C for 9 days maintained its color, firmness and a microbial count below regulatory limits.

This is the first study to identify the best decontamination method to reduce the microbial counts on turnips and establish the best storage conditions for shredded turnips. It has provided the basis of future intervention technologies to enhance the microbiological and physical qualities of shredded turnips and other fresh-cut produce in Singapore. Aerobic natural polyethylene packaging is advisable for the cold storage of treated shredded turnips for the local low cost production context.

Figure shows the reduction (log cfu/unit-turnip) in aerobic mesophilic count, yeasts and molds and Salmonella spp. with sterile distilled water, AcEW, ASC, CPC, chlorine, ozone and NaDCC treatments [Image credit: Yuk Hyun-Gyun]

Reference

Tan SY, Mikš-Krajnik M, Neo SY, Tan A, Khoo G H, Yuk H-G. “Effectiveness of various sanitizer treatments for inactivating natural microflora and Salmonella spp. on turnip (Pachyrhizus erosus)”. Food Control. 54 (2015) 216.