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This paper presents the triaxial testing results of a study in which biocementation processes were employed to observe the behaviour at small strains of sand matrix. Biocementation was achieved using the microorganism Sporosarcina pasteurii, an aerobic bacteria growth in natural soil deposits. The microbes were introduced to the sand specimens in a liquid growth medium with three different amounts of urea and dissolved calcium sources. Subsequent cementation treatments were passed through the specimen under confining pressure. The results were assessed by local strain measurements using LVDTs. A series of undrained compression triaxial tests indicate that at small strain levels the observed stiffness-strain behaviour of biocemented sand specimens appeared to be significantly high for all three treatment levels. The response of biocemented sands was found to be similar to that of calcite and lime cemented specimens, which represent conventional cementing agents. Scanning electron microscopy pictures and energy dispersive X-ray were taken to verify the formation of cement at three different concentrations. [ABSTRACT FROM AUTHOR]

In this study, 180 red chilli pepper (RCP) berry samples were obtained from two different croplands of Gaziantep and Kahramanmaraş (Turkey) in August, September and October. RCP berry samples were dried under sunlight and grinded. Ground red chilli pepper (GRCP) samples were analysed for aflatoxins (AFs, sum of B1, B2, G1and G2) and AFB1contamination. According to the results, in 49 of 180 samples, AFB1and in 37 samples, AFs were higher than legal limits. The lowest amounts of AFs and AFB1were obtained in August and the highest amounts in October.χ2analysis showed that there were no significant differences (p > 0.05) between cities among 3 months according to number of samples with AFs and AFB1above legal limits. According to the Duncan multiple-range test, there was no significant difference between all months. Strict measures are necessary to produce high-quality GRCP. RCP berry must be treated to reduce moulds before production of GRCP. [ABSTRACT FROM AUTHOR]

In total, 240 samples were randomly collected from different locations in Gaziantep Turkey, 120 of which were unpacked and packed ground red chili pepper and 120 of which were unpacked and packed pistachio nuts. All samples of the unpacked and packed ground red chili pepper were found to be contaminated with aflatoxins and aflatoxin B1. Three (9.4%) of the packed ground red chili pepper samples were over the legal limit of aflatoxin B1 while 55 (62.5%) of the unpacked samples were over the legal limit. Thirty four (36.2%) of the unpacked pistachio nut samples were contaminated with aflatoxins. There is a need to strictly prohibit the use of batches of ground red chili pepper and pistachio nuts containing aflatoxins. [ABSTRACT FROM PUBLISHER]

In this study, inhibitory effects of bayleaf, rosemary, sage, and thyme hydrosols on the growth ofStaphylococcus aureusinoculated on fresh-cut apples were investigated using several sigmoidal models (modified Gompertz, logistic, Richards, Stannard, and Whiting and Buchanan). In addition, these models were compared to describe the inactivation ofS. aureusby fitting the experimental data using nonlinear models and various statistical parameters (the mean percentage error, the mean bias error, the root mean square error, the modeling efficiency, and chi-square parameters) as well as determination of coefficient (R2). The modified Gompertz, logistic, and Stannard models exhibited better fits than Richards and Whiting and Buchanan models regarding these statistical parameters. Rosemary and thyme hydrosols were found to be the most efficient sanitizers in reducing theS. aureusnumbers. Results demonstrate that predictive models could be utilized for describing the inactivation or survival ofS. aureuson fresh-cut apple with the effects of the treatments with plant hydrosols. [ABSTRACT FROM PUBLISHER]

The inactivation kinetics of high hydrostatic pressure for Salmonella typhimurium (KUEN 137) inoculated in tryptone soy broth (TSB) and foods (raw milk and orange juice) were studied from 250 to 400 MPa, 15-45 °C and pH adjusted from 5.0 to 7.0. The rate of inactivation of S. typhimurium during the initial 10 min was far greater than during the remaining treatment time. The inactivation of S. typhimurium showed two-phase inactivation (fast to slow). Decimal reduction times (D value) for S. typhimurium in the second phase were 4.61, 2.59, 2.09, and 1.80 min at 250, 300, 350, and 450 MPa, respectively, in TSB after 10 min (second phase). D values were 1.75 and 1.50 min for S. typhimurium in milk and orange juice, respectively, at 300 MPa (second phase) and the k values were 1.32 and 1.54 min-1, respectively (second phase). The rate of inactivation increased in increasing temperature and there were significant (P<0.05) reductions in the S. typhimurium at treated temperatures, pressures, and pH. The use of inactivation could be beneficial to the food industry for optimizing process conditions. [ABSTRACT FROM AUTHOR]