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The present work aims at contributing to the knowledge of the fate of 5 pesticides in olives in order to evaluate how washing may affect the presence of these residues in this fruit (and consequently in olive oil). For this purpose, olives were sprayed with commercial formulations containing the active ingredients and a series of analyses were performed for 64 d by using gas chromatography with mass spectrometric detection. Selected pesticides, ranked by their importance, were diuron, terbuthylazine, simazine, α-endosulfan, and β-endosulfan. The pesticide fraction, which was not removable from olives by washing, increased with time after treatment until their degradation started at week 6. Washing performed 1 d after treatment was the most effective in reducing residues, especially for simazine. Consequently, the washing step performed in olive mills could be effective in removing those herbicide residues present in olives as a consequence of contact with contaminated soil for a short time. This happens when olives are dropped and harvested off the ground by means of brushes or suction equipment. [ABSTRACT FROM AUTHOR]

The mechanical and bacterial barrier properties of washed (tap water, sodium carbonate, Na2CO3, sodium hypochlorite, NaOCI) noncoated eggs and eggs coated with soy protein isolate (SPI), whey protein isolate (WPI), carboxylmethyl cellulose (CMC), or wheat gluten (WG) were evaluated. All coated eggshells showed greater puncture strength than those of noncoated eggs. The film-coated eggs reduced post-wash bacterial penetration as measured by dye penetration method. WPI coating completely inhibited blue dye penetration on average. These results suggest that WPI coatings can be used to reduce breakage of eggshell and egg microbial contamination. [ABSTRACT FROM AUTHOR]

Washing of fresh-cut spinach with aqueous chlorine solutions eliminates foreign matter, removes cellular fluids produced by cutting and reduces the initial microbial contamination. Response Surface Methodology was used to evaluate the effect of initial chlorine concentration (25 to 125 ppm), water-to-produce ratio (10 to 26 L/kg) and washing time (2 to 8 min) on the total and available chlorine depletion and the total microbial count reduction after washing. All variables affect the chlorine depletion but the microbial count reduction was only influenced by initial chlorine concentration and washing time. Different combinations of the variables were determined by the predictive models to reduce microbial contamination assuring residual levels of chlorine in the washing solution. [ABSTRACT FROM AUTHOR]

An experimental washing process for fresh mushrooms entailing immersion in 5% H2O2, followed by application of a sodium erythorbate-based browning inhibitor, was optimized, scaled up, and made continuous. The laboratory process described previously was modified by adding a pre-wash step using 0.5% to 1% H2O2, increasing the wash solution H2O2 concentration from 3% to 5%, and substituting 4% sodium erythorbate + 0.1% NaCl for the more complex browning inhibitor formulation used previously. A continuous, commercial-scale washing facility was built to test the new process. Mushrooms washed by this process ware free of adhering soil, less subject to brown blotch than conventionally washed mushrooms, and at least as resistant to enzymatic browning as unwashed mushrooms during storage at 4 °C. Storage at 10 °C accelerated development of brown blotch and browning. [ABSTRACT FROM AUTHOR]

Factors limiting efficacy of H2O2 washes and alternative decontamination strategies were investigated with Golden Delicious apples, inoculated with nonpathogenic Escherichia coli. Post-treatment rinsing decreased efficacy by eliminating residual H2O2. A 2-stage wash incorporating a rinse to remove surfactant residues prior to H2O2 application was developed. Rapid attachment of E. coli to apples prevented effective removal by washing with water. Surviving E. coli following a 5% H2O2 wash were concentrated in stem and calyx areas. Survival was independent of the time interval between inoculation and washing. E. coli inoculation of punctured apple surfaces resulted in growth at 20 °C and greater survival after washing with 5% H2O2. Improved decontamination methods are needed. [ABSTRACT FROM AUTHOR]