Organic acid based sanitizers and free chlorine to improve the microbial quality and shelf-life of sugar snaps

Abstract

A screening in a sugar snaps packaging company showed a converged build-up of aerobic psychrotrophic plate count (APC) (ca. 6.5 log CFU/100 mL), yeasts and molds (Y&M), and lactic acid bacteria (LAB) (both ca. 4.5 log CFU/100 mL) in the wash water in the absence of water sanitizer, and a low build-up of chemical oxygen demand (30 ± 5 mg O 2 /L) and turbidity (5.2 ± 1.1 NTU).Decontamination experiments were performed in the lab with Purac FCC 80® (80% L(+) lactic acid), two other commercial water sanitizers based on organic acids (Natraphase-ABAV®, and Natraphase-FVS®) and chlorine to evaluate their performance in reduction of the sugar snaps microbial load as well as their functionality as disinfectant of the wash water to avoid cross-contamination.An additional 1 log reduction of APC on the sugar snaps was achieved with lactic acid in the range 0.8 to 1.6 %, ABAV 0.5 %, and free chlorine 200 mg/L when compared to a water wash, while no significant difference in the numbers of Y&M was obtained when washing in sanitizer compared to water. There was no significant influence of the studied concentration and contact time on decontamination efficiency. Treatment with lactic acid 0.8% resulted in a lower APC contamination on the sugar snaps than on the untreated and water washed samples for 10 days. Chlorine 200 mg/L was the only treatment able to maintain the Y&M load lower than the untreated samples throughout the entire storage duration. The use of water sanitizers could not extend the sensorial shelf-life. Microbial loads were not indicative/predictive for visual microbial spoilage (shelf-life limiting factor), whereas maturity and amount of damage at the calyx end of the pods were.

Effect of Disinfectants on Preventing the Cross-Contamination of Pathogens in Fresh Produce Washing Water

“…Nevertheless, the ability to remove naturally present microorganisms from fresh-cut produce is limited (0.5–2.0-log reduction), i.e. , some microbial reductions occur, but total reduction is unachievable [ 4 , 5 , 6 , 7 ]. These limitations are attributed to microbial attachment to surfaces, including those at crevices or cut edges, or as a result of irregular surface structures.…”

Neutral electrolyzed water (NEW), chlorine dioxide, organic acid based product, and ultraviolet-C for inactivation of microbes in fresh-cut vegetable washing waters

“…In that study lactic acid was more effective than citric acid and E. coli was more sensitive to both acids than L. monocytogenes . In the study by van Haute, Uytterdaele, and Sampers () weak organic acids in general were inefficient water disinfectants.…”

Comparison of Generally Recognized as Safe Organic Acids for Disinfecting Fresh-cut Lettuce

“…Lianou, Koutsoumanis, and Sofos (2012) also believed that the decontamination efficacy of organic acids cannot be evaluated when different types of acids are used and different tissues are treated. Moreover, the use of high concentrations of organic acids, such as 5% acetic acid (Chang & Fang, 2007; Wu, Doyle, Beucgat, Wells, Mintz, & Swaminathan, 2000) and lactic acid (> 1.6%) (Van Haute, Uyttendaele, & Sampers, 2013), to achieve good bactericidal effects can yield poor organoleptics (Ölmez & Kretzschmar, 2009). In addition to microbial reduction, the effects of organic acids on physical qualities, such as color and electrolyte leakage, should also be considered.…”