Multidrug Resistance and Serotype Distribution of Salmonella Enterica Isolated from Homemade Recipe Fermented Ground Pork (Nham) in Northeastern Thailand

Salmonellosis is caused by a thousand serotypes of Salmonella enterica. The sour taste inherent to Nham leads people believe that this fermented ground pork dish is safe from pathogenic microorganisms. The aim of this study was to evaluate the prevalence, serotype, drug susceptibility, and antimicrobial resistance (AMR) genes of Salmonella spp. in homemade recipes of Nham. There were 52 samples from different Nham makers in 3 northeastern provinces of Thailand collected between August and November 2019. Further, 30 Salmonella isolates (57.7 %) and 14 different serovars were identified: S. Rissen (23.3 %) was the most prevalent, followed by S. Typhimurium (16.7 %), S. Give and S. Virchow (10 % each), and S. Agona and S. Kouka (6.7 % each). All isolates carried AMR genes but 7 (23.3 %) were antibiotic susceptible and 23 (76.7 %) borne a resistance phenotype. The Salmonella isolates were resistant to tetracycline (63 %), sulfamethoxazole/trimethoprim (36.7 %), streptomycin (33.3 %), nalidixic acid (30 %), cefotaxime (16.7 %), and enrofloxacin (3.3 %). Among the 23 AMR genes in our analysis, there were gyrB (100 %), tetA (93.3 %), aadA (93.3 %), sul1, sul2, sul3 (23.3 - 33.3 %), dfrA12 (16.7 %), qnrS, (6.7 %), and mcr6 (6.7 %). Two strains had the mcr6 gene but were susceptible to colistin. Our findings suggest that naturally occurring lactic acid bacteria in the Nham products are insufficient to inhibit Salmonella contamination of this pork-based food. HIGHLIGHTS Highly presence of Salmonella in fermented ground pork (Nham) All identified Salmonella isolates in the Nham have AMR genes A few Salmonella isolates carry AMR genes but are antibiotic susceptible Two Salmonella isolates contain the mcr6 gene but are susceptible to colistin

A Resonant Coupler for Subcutaneous Implant

A resonator coupler for subcutaneous implants has been developed with a new impedance matching pattern added to the conventional loop antenna. The tuning element of a concentric metal pad contributes distributed capacitance and inductance to the planar inductive loop and improves resonance significantly. It provides a better qualify factor for resonant coupling and a much lower reflection coefficient for the implant electronics. Practical constraints are taken into account for designs including the requirement of operation within a regulated frequency band and the limited thickness for a monolithic implant. In this work, two designs targeting to operate in the two industrial, scientific, and medical (ISM) bands at 903 MHz and 2.45 GHz are considered. The tuning metal pad improves their resonances significantly, compared to the conventional loop designs. Since it is difficult to tune the implant antenna after implantation, the effects of tissue depth variations due to the individual’s surgery and the appropriate implant depths are investigated. Simulations conducted with the dielectric properties of human skin documented in the literature are compared to measurements done with hydrated ground pork as phantoms. Experiments and simulations are conducted to explain the discrepancies in frequency shifts due to the uses of pork phantoms. The design method is thus validated for uses on human skin. A noninvasive localization method to identify the implant under the skin has been examined and demonstrated by both simulations and measurements. It can efficiently locate the subcutaneous implant based on the high quality-factor resonance owing to the tuning elements in both implant and transmitter couplers. The planar resonant coupler for wireless power transfer shows good performance and promise in subcutaneous applications for implants.

Impact of Interventions on the Survival of Salmonella enterica I 4,[5],12:I:- in Pork

A mixed culture of different isolates of Salmonella serovar I 4,[5], 12:i:- was compared to a mixed culture of reference Salmonella serovars as well as non-pathogenic Escherichia coli surrogates.. The two groups of Salmonella were compared for their resistance to commonly used pork carcass interventions, survival in ground pork and thermal resistance in ground pork. There were no observed differences between the response of the two different groups of Salmonella serovars and the non-pathogenic E. coli surrogates within intervention type. There were no observed differences in the recovery and survival of the two different groups of Salmonella serovars in pork which had been treated with interventions, ground and stored at 5 o C for two weeks. Finally, there were no observed differences in heat resistance between the two different groups of Salmonella serovars in ground pork which had been treated with interventions, ground and stored at 5 o C for two weeks. However, there were observed differences in heat resistance in both groups of Salmonella serovars associated with refrigerated storage. The heat resistance of both groups of Salmonella serovars decreased after refrigerated storage. The results of these experiments demonstrate that there were no observed differences between the responses of Salmonella serovar I 4,[5], 12:i:- when compared to the reference Salmonella serovars to commonly used interventions in the pork industry, and therefore do not present a unique challenge to the pork industry.

A Salute to PVT TIM HiLL: Indispensable amino acids and global human health

Students are taught the study mnemonic PVT TIM HiLL to memorize nineindispensable amino acids (IAA); Phenylalanine, Valine, Threonine, Tryptophan,Isoleucine, Methionine, Histidine, Leucine, and Lysine.  The Food and Animal Organization (FAO)recommended IAA be treated as individual nutrients on food labels because‘crude protein’ alone does not indicate protein quality.  Protein quality, determined by digestible IAAscore (DIAAS) is calculated for three life stages; birth to 6 months; 6 monthsto 3 years, and 3 years and older.  Foodspossessing DIAAS greater than 100 are “excellent” protein quality, DIAASbetween 75 and 99 are ‘good’, while foods with DIAAS < 75 cannot make aprotein claim.  Processing, heating,and(or) grinding can decrease or improve plant and animal IAA digestibility.For children six months to three years, ground pork, smoked-cooked bacon,cooked pork leg, cured ham, cooked pork loin, salami, beef/pork bologna, beefjerky, and medium and medium rare beef ribeye steaks can be described‘excellent’.  Cooked ground beef can beclassified as ‘good’ or ‘excellent’ depending on the study, while theImpossible and Beyond meat-alternative burgers and well-done ribeye can beclassified as ‘good’ sources of IAA for young children.  For persons > 3 years, all meat categoriesbut cooked ground beef can be classified ‘excellent’ sources of IAA.  For meat alternatives, Impossible Burger®could be classified as ‘excellent’ but Beyond Burger® could only claim to be‘good’.  Protein quality claims forindividual food ingredients can be diminished when consumed with a lowerprotein quality item such as a wheat flour bun. To provide meals that are adequate in all IAA, the protein quality ineach food item must be determined.  Mixedmeals must be adjusted for protein quality by combining low quality proteins(present in cereals and grains) with higher quality proteins (present in foodsof animal origin).

Shiga Toxin-Producing Escherichia coli (STEC) and STEC-Associated Virulence Genes in Raw Ground Pork in Canada

Shiga toxin-producing Escherichia coli (STEC) O157:H7/NM and some non-O157 STEC are foodborne pathogens. In response to pork-associated O157 STEC outbreaks in Canada, we investigated the occurrence of STEC in Canadian retail raw ground pork during the period of November 1, 2014 and March 31, 2016. Isolated STEC were characterized to determine the Shiga-toxin gene ( stx ) subtype and the presence of virulence genes encoding intimin ( eae ), and enterohemorrhagic E. coli hemolysin (hlyA) . O157 STEC and non-O157 STEC were isolated from 0.11% (1/879) and 2.24% (13/580) of the pork samples. STEC virulence gene profiles containing both eae and hlyA were found only in the O157 STEC ( stx 2a , eae , hlyA ) isolate. The eae gene was absent from all non-O157 STEC isolates. Of the 13 non-O157 STEC isolates, two virulence genes of stx 1a and hlyA were found in four (30.8%) O91:H14 STEC isolates, while one virulence gene of stx 2e, stx 1a , and stx 2a was identified in five (38.5%), two (15.4%) and one (7.7%) STEC isolates respectively of various serotypes. The remaining non-O157 STEC isolate carried stx 2 , but the subtype is unknown as this isolate could not be recovered for sequencing. O91:H14 STEC ( stx 1a, hlyA ) was previously reported in association with diarrhea illnesses, while the other non-O157 STEC isolates identified in this study are not known to be associated with severe human illnesses. Virulence gene profiles identified in this study indicate that the occurrence of non-O157 STEC capable of causing severe human illness is rare in Canadian retail pork. However, O157 STEC in ground pork can occasionally occur, therefore education regarding the potential risks associated with STEC contamination of pork would be beneficial for the public and those in the food industry in order to help reduce foodborne illnesses.

Predictive modelling of TBARS changes in the intramuscular lipid fraction of raw ground pork enriched with plant extracts

The aim of the study was to develop and compare the predictive models of lipid oxidation in minced raw pork meat enriched with selected plant extracts (allspice, basil, bay leaf, black seed, cardamom, caraway, cloves, garlic, nutmeg, onion, oregano, rosemary and thyme) by investigation TBARS values changes during storage at different temperatures. Meat samples with extract addition were stored under various temperatures (4, 8, 12, 16, and 20°C). TBARS values changes in samples stored at 12°C were used as external validation dataset. Lipid oxidation was evaluated by the TBARS content. Lipid oxidation increased with storage time and temperature. The dependence of lipid oxidation on temperature was adequately modelled by the Arrhenius and log-logistic equation with high R2 coefficients (0.98–0.99). Kinetic models and artificial neural networks (ANNs) were used to build the predictive models. The obtained result demonstrates that both kinetic Arrhenius (R2 = 0.83) and log-logistic (R2 = 0.84) models as well as ANN (R2 = 0.99) model can predict TBARS changes in raw ground pork meat during storage.

Predictive Modeling of Thiol Changes in Raw Ground Pork as Affected by 13 Plant Extracts—Application of Arrhenius, Log-logistic and Artificial Neural Network Models

In this study, predictive models of protein oxidation, expressed as the content of thiol groups (SH), in raw ground pork were established and their accuracy was compared. The SH changes were monitored during, maximum, 11 days of storage at five temperature levels: 4, 8, 12, 16, and 20 °C. The effect of 13 plant extracts, including spices such as allspice, black seed, cardamom, caraway, cloves, garlic, nutmeg, and onion, and herbs such as basil, bay leaf, oregano, rosemary, and thyme, on protein oxidation in pork was studied. The zero-order function was used to described SH changes with time. The effect of temperature was assessed by using Arrhenius and log–logistic equations. Artificial neural network (ANN) models were also developed. The results obtained showed very good acceptability of the models for the monitoring and prediction of protein oxidation in raw pork samples. High average R2 coefficients equal to 0.948, 0.957, and 0.944 were obtained for Arhhenius, log-logistic and ANN models, respectively. Multiple linear regression (MLR) was used to assess the influence of plant extracts on protein oxidation and showed oregano as the most potent antioxidant among the tested ones in raw ground pork.