Notes

High-Performance Coaxial Asymmetry " floating " fibrous Supercapacitors having a Poly(plastic alcohol)-Montmorillonite Separator.
elf, and as an alternative to chlorine for washing fresh produce. HIGHLIGHTS Published 2020 by the International Association for Food Protection. Not subject to U.S. Copyright.ABSTRACT d-Tryptophan (d-Trp) has a significant inhibitory effect on growth of gram-negative bacteria under osmotic stress. However, the inhibitory effect of d-Trp on the gram-positive Listeria monocytogenes under chilled and thermal stresses has not been evaluated previously. The effect of d-Trp on L. monocytogenes growth under cold and/or heat stress in milk and cream was dependent on the magnitude of the temperature stress. Low temperatures (4, 7, and 10°C) and treatment with 40 mM d-Trp resulted in significant inhibition of L. monocytogenes growth during the 4-week storage period. Lower temperatures more effectively inhibited growth. When added before thermal processing, 40 mM d-Trp completely inactivated L. monocytogenes (>6-log reduction) heated at 60°C for 25 min or 65°C for 20 min. These results suggest that d-Trp can be used as a preservative for controlling the growth of L. monocytogenes in milk and cream at refrigeration temperatures and could be used to enhance the thermal inactivation of L. monocytogenes. HIGHLIGHTS Copyright ©, International Association for Food Protection.ABSTRACT The Agricultural Marketing Service procures boneless and ground beef for federal nutrition assistance programs. It tests procured beef for concentrations of standard plate counts (SPCs), coliforms, and Escherichia coli and for the presence of Salmonella and Shiga toxin-producing E. coli. Any lot exceeding predefined critical limits (100,000 CFU g-1 for SPCs, 1,000 CFU g-1 for coliforms, and 500 CFU g-1 for E. coli) or positive for Salmonella or Shiga toxin-producing E. coli is rejected for purchase. Between 1 October 2013 and 31 July 2017, 166,796 boneless beef lots (each approximately 900 kg) and 25,051 ground beef sublots (each approximately 4,500 kg) were produced. Salmonella was detected in 1,955 (1.17%) boneless beef lots and 219 (0.87%) ground beef sublots. Salmonella sample size increased from an individual 25-g sample to a co-enriched 325-g sample on 1 March 2015. Salmonella presence was associated with season (lowest in spring), larger sample size, and increased log SPC in boneless and grounod Protection.ABSTRACT The effects of high hydrostatic pressure (HHP) treatments on histamine-forming bacteria (HFB) Morganella morganii and Photobacterium phosphoreum in phosphate buffer and tuna meat slurry were investigated using viability counting and scanning electron microscopy. The first-order model fits the destruction kinetics of high pressure on M. morganii and P. phosphoreum during the pressure hold period. The D-values of M. morganii (200 to 600 MPa) and P. phosphoreum (100 to 400 MPa) in phosphate buffer ranged from 16.4 to 0.08 min and 26.4 to 0.19 min, respectively, whereas those in tuna meat slurry ranged from 51.0 to 0.09 min and 71.6 to 0.19 min, respectively. M. morganii had higher D-values than P. phosphoreum at the same pressure, indicating it was more resistant to HHP treatment. HFB had a higher D-value in tuna meat slurry compared with that in phosphate buffer, indicating that the HFB were more resistant to pressure in tuna meat slurry. The Zp values (pressure range that results in a 10-fold change in D-value) of M. morganii and P. phosphoreum were 162 and 140 MPa in phosphate buffer and 153 and 105 MPa in tuna meat slurry, respectively. Damage to the cell wall and cell membrane by HHP treatments can be observed by scanning electron microscopy. To our knowledge, this is the first report to demonstrate that HHP can be applied to inactivate the HFB M. morganii and P. phosphoreum by inducing morphological changes in the cells. HIGHLIGHTS Copyright ©, International Association for Food Protection.ABSTRACT During poultry slaughter and processing, microbial cross-contamination between individual chickens is possible, as well as from one slaughter animal to the next without direct contact. One option for reducing the risk of cross-contamination is to decrease the number of microorganisms on contact surfaces by using disinfectants. The aim is to decontaminate the surfaces coming into direct contact with the carcasses. In the present study, the effectiveness of different disinfectants was investigated in laboratory settings, simulating the conditions in the slaughterhouses and in a chicken slaughterhouse. For this, an artificial residue substance (consisting of yeast extract, albumin, and agar) was developed, tested, and included in the assays. Two disinfectants were tested under laboratory conditions lactic acid (5 and 6.67%) and peracetic acid (0.33 and 0.5%). At the slaughterhouse, peracetic acid (0.021%) was used. In the laboratory tests, it was found that the peracetic acid solution had the highest disinfection potential with respect to an Escherichia coli strain (reduction >4 log CFU mL-1) at 0.5% without an artificial residue substance. The tested lactic acid solutions also showed the highest disinfection potential against a Pseudomonas aeruginosa strain, without an artificial residue substance. When applying the artificial residue substance, the reduction potential of lactic acid and peracetic acid was decreased to less than 1.4 log CFU mL-1. Application of peracetic acid in the slaughterhouse reduced the number of total aerobic bacteria by more than 4 log CFU mL-1 and the number of Enterobacteriaceae by more than 3 log CFU mL-1, depending on the place of sampling. HIGHLIGHTS Published 2020 by the International Association for Food Protection. This is an open access article under the CC BY-NC-ND license (https//creativecommons.org/licenses/by-nc-nd/4.0/).ABSTRACT Isothermal inactivation experiments often are used to investigate the thermal resistance of pathogens, such as Salmonella, in foods; however, little is known about the reproducibility of such experimental methodologies. PD-L1 inhibitor The objective of this study was to quantify the reproducibility of Salmonella isothermal resistance results via a six-laboratory comparison. Inoculation was performed at a single location and then distributed to each laboratory for isothermal analysis. Salmonella Agona 447967 was inoculated into oat flour, re-equilibrated to a water activity (aw) of 0.45, and then packaged and distributed to each laboratory. Before conducting the inactivation trials, each laboratory was required to verify the inoculated product's aw, enumerate Salmonella population levels, and verify that the isothermal treatment medium was at the target temperature (80°C). All laboratories were required to process at least three replications, collect at least six sample time points with three subsamples at each sampling point, enumerate survivors using an identical plating methodology and media, and verify that the temperature did not substantially change during isothermal treatment.
Website: https://www.selleckchem.com/products/pd-1-pd-l1-inhibitor-3.html