Surface Decontamination of Fresh, Whole Peaches (Prunus persica) Using Sodium Hypochlorite or Acidified Electrolyzed Water Solutions

Abstract

Nearly half (45%) of the U.S. peach production is sold through the fresh market sector, making post-harvest disinfectant washing treatments a critical step for reducing surface microorganisms. This study was conducted to determine the effects of various disinfectant washing treatments on the surface decontamination of fresh whole freestone peaches. Minimal application of disinfectant washing treatments (five-second dip) reduced numbers of Listeria innocua recovered from inoculated peaches by 93% (acidified electrolyzed water containing 22 ppm sodium hypochlorite, pH 2.8) or 96% (chlorine containing 22 ppm sodium hypochlorite, pH 8.2) compared to cell counts on unwashed or water-only washed peaches. Increasing the wash time to 40 minutes resulted in a greater reduction in numbers of Listeria innocua recovered from the surfaces of peaches (99.95% and 99.9% for acidified electrolyzed water and chlorine treatments, respectively). All of the washing treatments decreased counts of total aerobic microorganisms on peaches (>92% reduction) when applied for 40 minutes. The results of this study demonstrate that washing peaches reduced but did not completely eliminate surface microorganisms.

Effects of alkaline electrolyzed water pretreatment on the physicochemical quality attributes of fresh nectarine during storage

“…Similarly, Ding et al, (2015) corroborate this by reporting a strong bactericidal activity of EW (30-70 mg/L) against Listeria monocytogenes. Recently, Hopkins et al, (2020) demonstrated the potential of acidic EW for surface decontamination of whole peaches.…”

Effect of pre‐treatment and freezing on the polyphenol oxidase activity and color stability of sliced peaches

“…3,4 Forty-five percent of the harvest is typically sold on the fresh market while the remaining 55% of the harvest will be either canned, frozen, dried, or used as an ingredient. 4,5 During processing, peaches are susceptible to enzymatic browning. Freezing has been employed successfully for the long-term preservation of peaches, 6 and 6% to 8% of the annual peach harvest is processed as frozen peaches.…”

“…In the USA, peach and nectarine production has been estimated to be nearly 22 million metric tons, up by 0.6 metric tons over the previously reported 2017/2018 production numbers 2 . Slightly more than 650 000 metric tons of peaches are harvested annually, valued at approximately 522 million US dollars 3,4 . Forty‐five percent of the harvest is typically sold on the fresh market while the remaining 55% of the harvest will be either canned, frozen, dried, or used as an ingredient 4,5 .…”

Application of Electrolyzed Water in the Food Industry: A Review

“…In the various food industries, electrolyzed water is used as disinfectant for cutting tools, an antimicrobial agent for the carcasses of poultry birds [28], and for disinfecting eggs in the meat industry [29]. In the fruits and vegetable processing industries [30], lettuce [31], pears [32], peaches [33], sprouts [34], apples [35], tomatoes [36], alfalfa seeds [37], strawberries, and their respective forms of processing equipment are disinfected using electrolyzed water [38].…”