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The use of sanitizers during produce wash operation is a common practice, but little is known about the effect of residual sanitizers on minimizing food safety risks associated with post-sanitizing cross-contaminations. This study investigated the effect of residual chlorine and organic acids on the survival and the attachment of E. coli O157:H7 and L. monocytogenes on spinach leaves during refrigerated storage. The pathogens were spot inoculated on chlorine (100 ppm), lactic acid (0.5%) and acetic acid (0.5%) treated leaves, and their survival during refrigerated storage (4 °C) was examined. A significant reduction (P

The study evaluated the effects of convective hot air drying temperatures (40, 50, 60 and 70 °C) with different pre-treatments (Potassium metabisulphite (KMS) and KMS + Citric acid) on drying as well as rehydration kinetics, color, texture and calcium oxalate content of elephant foot yam (EFY) cubes. Moisture diffusivity (6.69 × 10−8-3.41 × 10−7 m2/s) and activation energy (25.18–32.46 kJ/mol) increased with pre-treatments and increase in drying temperature. Rehydration ratio increased with increase in drying as well as rehydration temperature compared to room temperature. Page and modified peleg models suited the best to describe drying and rehydration kinetics of EFY cubes, respectively. Color value ‘L’ decreased with increase in drying temperature and opposite trend was observed for ‘a’ and ‘b’ value. However the dried samples treated with KMS + blanching showed higher ‘L’ value and the highest L value (90.35) was observed at 50 °C. Sample hardness (94.34–349.57 N) and rupture energy (18.42–191.35 N/mm2) decreased with increase in drying temperature. Significant (p

Traditional and novel food processing methods has been employed to reduce the anti-nutritional factors (ANFs) such as phytic acid, trypsin inhibitors, tannins, saponins and oxalate to enhance the safety and quality of edible grains. Among these, microwave processing has advantage of being fast, consistent, safe, efficient, and green technology for the reduction of the ANFs. Microwave processing power and duration has significant effect on the inactivation of ANFs and needs to be critically evaluated for effective application on food grains. The reduction of heat labile ANFs by microwave heating is due to degradation by heat along with formation of insoluble complex. Pre-treatment such as soaking enhance their reduction through leaching and hydrolysis. The present review illustrates the mechanism, scope, application and future prospects of microwave processing to reduce the different ANFs present in food grains.

Roasting of chickpea is an important step for the development of value added product, performed normally at 150–350 °C using conduction, convection and radiation. In this study, continuous roasting of chickpea grains was performed without incorporating sand and using a novel method. The roasting characteristics, physico-functional and antioxidant properties of products obtained through this method at 250, 270, 290, 310, 330 and 350 °C were compared to unroasted grain. The results showed that grains roasted at 350 °C possessed highest puffing index, high expansion index and lowest length/width ratio. Color of roasted chickpea flour changed from light to dark with a simultaneous increase in ‘a’ and ‘b’ value. Functional properties in terms of water absorption index and oil absorption capacity were between 1.97-2.99 and 1.25–1.81 g/g respectively. Total flavonoid content of chickpea decreased by 10% while an increase occurred in total phenolic content (46%) and antioxidant activity (60%) respectively. FTIR and DSC profiles of roasted grain flour indicated changes in different functional groups and crystalline nature of starch. This method demonstrated that chickpea may be roasted effectively without any contamination in lesser time compare to other processes. Novel continuous roasting therefore could be considered for chickpea roasting industry.

Gaseous chlorine dioxide, a strong oxidizing agent can be utilized as an effective alternative sanitizing agent. This study evaluated the efficacy of low concentration (≤5 mg/L) gaseous chlorine dioxide (ClO₂) treatment with gas permeable sachets in reducing the levels of Salmonella, E. coli O157:H7, and Listeria monocytogenes on strawberries and blueberries. Strawberries and blueberries were spot inoculated (107 CFU/g) with multi-strain cocktails of each pathogen and dried for 120 min inside a biosafety cabinet. A treatment chamber was successfully designed to sanitize inoculated samples in sealed 5 gallon chambers containing gaseous ClO₂ sachets. The gaseous ClO₂ overhead concentration was maintained within the range of 3.32 ± 1.73 to 4.95 ± 2.19 mg/L for up to 3 h of treatment. Gaseous ClO₂ treatments reduced pathogen levels significantly (P

Sanitizer wash may induce bacterial pathogens on produce surfaces into a viable but-nonculturable (VBNC) state and may go undetected by conventional plating methods. This study investigated the effect of chlorine and lactic acid on the viability of E. coli O157: H7 on spinach leaves right after the treatment and during refrigerated storage using propidium monoazide staining and real-time PCR (PMA-qPCR). Baby spinach leaves inoculated with E. coli O157: H7 were washed with chlorine (100 ppm) and lactic acid (0.5%) for 5 min and 3 min, respectively. The residual effect of the treatments was examined by inoculating the sanitizer-treated leaves with the pathogen and allowing them to sit for up to 48 h at 4 °C. Chlorine and lactic acid wash resulted in the reduction in viable E. coli O157: H7 counts by 2.51 and 3.43 log CFU/g, respectively. After 48 h of refrigerated storage, viable E. coli O157:H7 population was significantly reduced by 2.86 log CFU/g on chlorine-treated leaves and by 4.42 log CFU/g on lactic treated leaves. This study emphasized the potential effect of chlorine and lactic acid in reducing viable E. coli O157: H7 population on produce surfaces.