Removal of Grit from Baby Leafy Salad Vegetables by Combinations of Sanitiser and Surfactant

Abstract

Grit composed of dirt, sand, and small stones adheres to baby leafy salad vegetables during the growing period and can sometimes be difficult to remove with sanitiser only or tap water. For the first time, the effect of a surfactant, sodium dodecyl sulphate (SDS), alone (0.025, 0.05, and 0.1% SDS) and in combination (0.05% SDS) with peroxyacetic acid (40 mg·L ⁻¹, PAA), on grit removal, quality, shelf-life, and taste of baby spinach was investigated. Increasing SDS from 0.025 to 0.1% resulted in a 21–50% increase in grit removal from spinach and coral lettuce. Overall, SDS treatments had no effect on microbial growth, colour, and electrolyte leakage during shelf-life. An increase in bruising, sliming, and yellowing scores was also observed regardless of the treatment, reaching an unacceptable score (<3) by d12 for all samples; however, yellowing scores were still within the acceptable range (>3) on d14. There were no differences in sensorial attributes, namely, flavour, aroma, and texture, between baby spinach samples treated with PAA alone or in combination with SDS. These results demonstrate that SDS treatment can be used to increase grit removal from baby leafy salad vegetables without compromising quality.