Phenolic compounds commonly occurring in fruits, vegetables and tea were studied for their effects on Listeria monocytogenes (L.m.), Escherichia coli O157:H7 (E.c.) and Salmonella Typhimurium (S.T.) in brain–heart infusion broth (BHI) and meat system. Incubated at 37C for 72 h in BHI, gentistic, benzoic and vanillic acids inhibited L.m., E.c and S.T. at 5,000 µg/mL by 2.8 to 3.0 log CFU/mL, 2.8 to 3.0 log CFU/mL and 2.7 to 2.9 log CFU/mL, respectively. Encapsulation of benzoic acid (1,100 µg/mL) in polylactic‐co‐glycolic acid nanoparticles inhibited 6.5 log CFU/mL of L.m. and S.T., and 6.0 log CFU/mL of E.c. at 48 h. In raw and cooked chicken meat systems, nanoparticle delivery of benzoic acid was effective against S.T. and L.m. (1.0 and 1.6 log CFU/g reduction of S.T. and 1.1 and 3.2 log CFU/g reduction of L.m. compared with 1.2 log CFU/g without nanoparticles on the days 9 and 14 of storage, respectively). These findings demonstrate the efficacy of phenolics on pathogen reduction delivered by nanoparticles and their potential for commercial food safety applications. PRACTICAL APPLICATIONS Nanotechnology is an emerging and promising technology that has been advocated for the delivery of antimicrobial phenolic compound extracts to effectively inhibit foodborne pathogens. The method improves the rate of inhibition compared with conventional delivery and retains the antimicrobial efficacy for a longer time. This hurdle technology using natural antimicrobials (phenolic compounds) and nanoparticle‐mediated delivery system can effectively decontaminate foodborne pathogens and improve food safety. Phenolic compounds can be used as natural and safer alternatives to chemical disinfectants in food systems and delivered using nanoparticles to better control pathogens for commercial food safety applications.

About 40000 people fall victim to Salmonella infections every year in the United States. Recent occurrences of Salmonella contaminated spinach and its recalls have accelerated the need for efficient antimicrobials targeting these pathogens. Our study was aimed at evaluating the inhibitory properties of malic, tartaric, and lactic acids, and grape seed extract (GSE) alone and in combinations and their application methods against Salmonella Typhimurium-inoculated spinach using a response surface method. Fresh spinach leaves were washed, disinfected with sodium hypochlorite solution (0.04% v/v), rewashed with sterile deionized (DI) water, and inoculated with a 2nd-day culture of S. Typhimurium (7.0 log CFU/mL). Adhered S. Typhimurium population on day 0 were 7.5 log CFU/g. These were treated with individual and combinations of organic acids with GSE or DI water (control) adjusted to the same pH as that of the test solutions with both the modes of application and leaves were refrigerated at 4 °C. Malic acid (2%) in combination with GSE (3%) or lactic acid (3%) sprayed electrostatically showed reductions of 2.6 to 3.3 log CFU/g compared to lower log reductions (0.0 to 0.3 log CFU/g) by day 14 if sprayed conventionally. These findings indicate that malic acid in combination with GSE/lactic acid solutions applied by electrostatic spraying exhibited higher inhibition of pathogens than conventional spraying and can be used for commercial applications to enhance food safety.

Soy protein isolate (SPI), has the highest protein content and wide range of health benefits. Soy peptides have been studied for their various beneficial effects including anti‐cancer, anti‐hypertensive, anti‐diabetic etc properties. However there is no literature regarding their anti‐Alzheimer's disease properties. Alzheimer's disease is the most common form of dementia and is the seventh leading cause of death in the United States and expected to become the sixth leading cause of death by 2013.In this study we aim to evaluate the anti‐aggregative property of alcalase hydrolysates of SPI. Since the anti‐aggregative properties against Alzheimer's β‐amyloid peptide (Aβ 1–42) depends on the peptide composition of the hydrolysates and the enzyme used, the effect of process conditions on SPI hydrolyzed with alcalase was investigated systematically using response surface methodology. Hydrolysis conditions for optimal β‐amyloid aggregation inhibition were defined using the response surface model of central composite design (CCD). The optimum conditions obtained by the model for hydrolysate (with maximum anti‐beta amyloid aggregation activity) preparation was found to be pH=8, Time=1 hr, E/S=0.5%, Temperature= 50 C which was in perfect correlation with the experimental model. This is by far one of the first studies to show that soy protein hydrolysates possess bio‐activity against beta amyloid peptide found in patients with Alzheimer's disease.Grant Funding Source: ABI