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Bacterial contamination on the outer grained hide of cattle serves as a significant challenge to the meat and hide processing plants regarding food safety. Cattle serves as a host to several bacteria including pathogens, which may become firmly lodged on a cattle’s hide during their lifespan and can facilitate cross contamination of the underlying meat and meat processing equipment in a slaughterhouse. In this study, the efficacy of sodium dichloroisocyanurate dehydrate (SDCIC), which belongs to N-halamine group of compounds is evaluated on inhibition of the natural-borne bacteria from the haired surface of cattle hide. Spray-washing with 0.25%, 0.50% and 0.75% aqueous SDCIC solutions reduced total aerobic bacteria on hide surface by 1.6 and 2.37 and 3.57 log CFU/50 cm2 respectively in 5 min. Similarly, in comparison with water spray, a 5 min treatment with 0.25, 0.50 and 0.75% SDCIC resulted in a reduction of Enterobacteriaceae (ENT) and related gram-negative bacilli (gnEB) counts by 1.2, 2.22 and 4.22 log CFU/50 cm2 respectively. The highest reduction of E.coli recovery of 1.48 log CFU/50 cm2 was obtained with a spray treatment of 0.75% SDCIC in 1 minute. Likewise, 0.75% SDCIC spray treatment resulted in 2.5 and 3.65 log CFU/50 cm2 reduction of Salmonella in 1 and 5 min, respectively in comparison to their respective controls. Leather from treated hides was tested to evaluate the effects of N-halamine solutions on structural, mechanical and subjective properties of produced leather in which no major detrimental impacts were found.

This study investigated the efficacy of ozone washing appliances for microbial decontamination of tomatoes and green onions. Produce were submerged for light or heavy washing in ozone Washer-A or -B (Washer-B generates higher levels of ozoneandagitation)ornonozoneWasher-C.Ozonewashingsreducedtotalaerobic mesophile counts on whole tomatoes but not green onions when compared to unwashed samples.Washer-B at heavy setting reduced coliform numbers on whole tomatoesby1.9 cfu/g.Furthermore,Washer-Byieldedmorethan2.0logreductions of Escherichia coli (inoculation level at ~6.3 log cfu/g) on the edible portions of tomatoes thanWasher-A at comparable settings.A follow-up study usingWasher-B showed that ozone application can significantly reduce E. coli and Salmonella in produce wash water to prevent cross-contamination. However, when compared to nonozonewashingof produce,improvedreductionof naturalandartificiallyinoculated microorganisms by ozone applications was not found. Microscopic observation corroborates microbial enumeration showing that removing nonedible portions (stem scars or root bulbs) of washed tomatoes and green onions is beneficial for microbial decontamination.

Chlorine dioxide (ClO(2)) is an antimicrobial agent available for commercial produce washing. This study examined the efficacy of ClO(2) at 5 parts per million (ppm) during spray washing of tomatoes (5.0 ml/s per fruit) for preventing Salmonella enterica transfer from inoculated roller brushes to fruit and wash runoff. Furthermore, the sanitizing effects of ClO(2) during spray washing at low and high flow rates (5.0 and 9.3 ml/s per fruit, respectively) on tomato surfaces (nonstem scar areas) with either newly introduced (wet) or overnight air-dried Salmonella inocula were investigated. Salmonella transfer from contaminated brushes to fruit surfaces was reduced 2.1 +/- 0.6 or 4.7 +/- 0.2 log cycles after spray washing with water for 40 s or with the ClO(2) solution for 10 s, respectively. Cross-contamination of Salmonella from brushes to wash runoff during fruit washing for 60 s decreased 5.9 +/- 0.3 log cycles when ClO(2) was used. Fruit washing using contaminated brushes and low flow-rate washing with either water or ClO(2) solution for 10 s reduced newly introduced Salmonella on fruit surfaces by 1.7 +/- 0.6 or 5.1 +/- 0.3 log cycles, respectively. For fruit surfaces with air-dried inocula, washing with water and using uncontaminated brushes for 10 to 40 s reduced Salmonella by 3.2 +/- 0.3 to 3.4 +/- 0.4 log cycles; and the reduction was significantly improved by using ClO(2), high flow rate, or a longer washing time. Washing with ClO(2) at tested flow rates for 10 to 60 s resulted in a 4.4 +/- 0.6 to 5.2 +/- 0.1 log reduction of air-dried Salmonella on fruit surfaces.

This study investigated spray wash treatments independently with Citrilow or Cecure for their effects on microbial concentrations and leather quality. Spray washing with Citrilow reduced aerobic mesophilic recovery by 2.42–2.78 log cycles 2.78–2.95 log cycles, and 3.32–3.72 log cycles on the belly, belly, and butt regions, respectively. After washing with Citrilow, Enterobacteriaceae/related gram‐negative enteric bacilli (ENT/gnEB) recovery counts reduced by, 2.14–2.57 log cycles, 3.06–4.08 log cycles, and 4.65–4.99 log cycles on the belly, head, and butt regions, respectively. Cecure significantly lowered aerobic bacterial levels on the belly, head, and butt regions by 6.00–6.12 log cycles, 1.40–1.65 log cycles, and 4.26–3.60 log cycles, respectively. Washing with Cecure significantly lowered ENT/gnEB counts by 3.65–3.01 log cycles and 2.17–3.17 log cycles on belly and butt regions. Subjective testing, grain structure analyses, and mechanical properties of leather made from fresh hides after Citrilow or Cecure treatments revealed no difference between the treatment and their corresponding controls. PRACTICAL APPLICATIONS: The purpose of this study is to investigate the ability of two antibiotics (Citrilow and Cecure) to reduce bacteria on the outer haired surface of cattle hides which serves as a potential source of cross‐contamination of pathogens to beef. In addition, while reducing probability of cross‐contamination during cattle processing, the quality of the byproducts need to be insured. In the cattle industry, antimicrobials and surfactants applied must be food safe and limit damage to the animal byproducts, in the case of this study hides which are used to produce leather. The results from this study may be beneficial for meat processing plants, hide preparers and leather manufacturers to identify antimicrobials that may limit bacterial cross‐contamination which can lead to food related illnesses while insuring the quality of one of the cattle industries main byproducts.

The potential of Salmonella population to rebound on non-washed and washed roma tomatoes and jalapeño peppers in humid storage at 4°C, 10°C, 15°C, 21°C, or 35°C for ≤12 days was investigated. The initial inoculation levels of Salmonella on peppers and tomatoes were 5.6 and 5.2 log CFU/cm(2), respectively. Air-drying of fruit surfaces resulted in contamination levels of 3.9 and 3.7 log CFU/cm(2) on inoculated peppers and tomatoes, respectively. At 21°C and 35°C, the levels of air-dried Salmonella inoculums on produce surfaces increased ≥2 log cycles, with the most rapid growth in the first 3 days. Mechanical washing on rollers (rinsing; R-treatment) or revolving brushes (rinsing and brushing; RB-treatment) with water decreased Salmonella counts by ≥2.5 log CFU/cm(2) on both peppers and tomatoes. After R- or RB-treatment, peppers stored at 21°C and 35°C permitted residual Salmonella (≤1.4 log CFU/cm(2)) to grow to 2.6-3.9 log CFU/cm(2). During storage, residual Salmonella (≤1.0 log CFU/cm(2)) on washed tomatoes increased to 3.1 log CFU/cm(2) at 35°C following R-treatment and 3.8 log CFU/cm(2) at 21°C following RB-treatment. Cold storage at 4°C and 10°C effectively prevented the proliferation of Salmonella on both washed and non-washed produce. The current study on jalapeño peppers and roma tomatoes demonstrated that Salmonella population can rebound on produce in humid storage before or after washing. The finding highlights the benefit of uninterrupted cold storage for safer produce operations.

A convenient bread making method involving prolonged fermentation of no-knead (nonkneaded) dough has become popular in recent years. In the present study, the microbial safety of no-knead dough made with a 375:325:5:1 weight ratio of flour, water, salt, and bread yeast was investigated. Three brands of dehydrated yeast were used for this study. The growth of inoculated Salmonella enterica and Staphylococcus aureus in no-knead dough during fermentation was significant (P