Search Results (4)

Staphylococcus aureus is a common causative agent of mastitis in dairy cattle, posing a substantial threat to animal health and resulting in significant economic losses. Preventive measures are usually in place to control the spread of the organism between animals and around the dairy environment; however, mastitis outbreaks can still be recurrent. During this investigation, a total of 30 S. aureus isolates were obtained from six deceased cows, all diagnosed with chronic mastitis during an outbreak in West Texas. The aim of this study was to evaluate the response of the S. aureus isolates causing severe mastitis infections to iodine treatments and their antibiotic susceptibility, planktonic growth, and biofilm formation. Udder skin was inoculated with S. aureus and subjected to various iodine concentrations of 0.25%, 0.38%, 0.50%, 0.75%, and 1.00%, with exposure times of 15 s, 10 s, and 60 s. The same concentrations were tested on S. aureus’s biofilm formation. The results of the antimicrobial susceptibility test indicate that the exposure time did not influence the treatment. Lower iodine concentrations were compared with 1.00%, as the standard treatment used by the dairy for teat disinfection, and statistical difference (p < 0.001) was evident in the 0.00% iodine treatment compared to the other iodine concentrations. Moreover, a significant difference (p < 0.001) emerged when comparing the 0.25% and 0.38% iodine concentrations with 1.00%. No difference (p > 0.161) was detected between 0.50%, 0.75%, and 1.00%. These results suggest that, under the conditions investigated, iodine can be lowered to around 50% of the currently used dose without negatively impacting microbial control. On the other hand, S. aureus strains were susceptible to the tested antibiotics, demonstrating that antimicrobial resistance does not always play a role in the persistent mastitis infections caused by S. aureus. Further microbial phenotypic typing conducted on S. aureus strains indicated a possible common source of the infections, demonstrating the potential of there being resident S. aureus strains at this dairy farm. Full article

The effect of carvacrol added to patties stored at 4 °C for 14 days, previously pressurized and vacuum-cooked (HPP-SVCOOK), was investigated. Three formulations were prepared (veal, plant-based product, and hybrid product). An emulsion made with olive and linseed oils was added. The physicochemical and microbiological qualities were assessed. Microbial tests indicated negligible growth of spoilage organisms in treated patties. No significant effect of carvacrol on the microbial loads of patties was noticed. Sulfite-reducing clostridia and Enterobacteriaceae were absent in the treated patties, whereas, in the treated veal and hybrid samples, 3 and 2 units of log cfu/g reduction for lactic acid bacteria and molds and yeasts were noted, respectively. On day 7 of storage, veal patties exhibited a significant reduction (p < 0.05) in the L* (53.9–49.3), hardness (32.3–21.4 N), springiness (0.8–0.7 N), cohesiveness (0.49–0.46), and chewiness (12.2–7.1) and a hike in the a* value (5.3–9.4). No significant changes in L* (59.1–58.6), a* (8.57–8.61), hardness (11.6–10.6 N), or cohesiveness (0.27–0.26) were observed in plant-based patties over the storage times, whereas reductions in springiness (0.5–0.4), chewiness (1.9–1.3), and b* (26.6–29.1) were noted in them. In hybrid patties, the L* (53.9–52.5) and b* values (24.9–24.3) were consistent but had a significant decrease in a* value (5.9–3.5) along the days of storage under study. The texture parameters of the hybrid patties altered were similar to those of veal patties during the 14-day storage time. In all samples, pH decreased with storage time. HPP-SVCOOK was effective on rendering safe and shelf-stable, ready-to-eat patties regardless of their matrix formulation. The addition of carvacrol had limited effects on the textural qualities of the HPP-SVCOOK products. Future studies need to be undertaken to assess the treated patties’ consumer acceptability and sensory profile. The study provides the basis for the development of novel meat-based and plant-based products that are microbiologically safe, with minimum physicochemical alterations during storage. Full article

The impact of high-pressure processing (HPP) alone and combined with sous-vide cooking (SVCOOK) on the physicochemical and sensory traits of patties from different fat and protein matrices was evaluated. Hydro-gelled and soya emulsions were tested in meat (M), hybrid (H) and plant-based (P) patties (six formulations). M patties with pork backfat were used as reference formulation. All samples were pressurized (350 MPa, 10 min) and the HPP + SVCOOK patties were subsequently vacuum-cooked (55 °C). Significant changes (p < 0.05) in physicochemical parameters were detected in HPP and HPP + SVCOOK samples. Hardness reached the maximum value (11.0 N) in HPP treated P patties with soya emulsion. The HPP + SVCOOK M patties with backfat recorded the highest hardness (29.9 N). Irrespective of the fat formulations, the sensory characteristics of the HPP and HPP + SVCOOK M patties showed a well differentiated profile compared to H and P patties. The highest intensities for fatness, flavor, chewiness and the lowest for friability were recorded in HPP + SVCOOK M patties with backfat. The differences in physicochemical and sensory parameters of HPP + SVCOOK patties were minimal. Successful fat replacement using either one of the soya or hydro-gelled emulsion could be conducted in HPP + SVCOOK patties. Full article

This review describes the effects of processing and preservation technologies on sensory and nutritional quality of meat products. Physical methods such as dry aging, dry curing, high pressure processing (HPP), conventional cooking, sous-vide cooking and 3D printing are discussed. Chemical and biochemical methods as fermentation, smoking, curing, marination, and reformulation are also reviewed. Their technical limitations, due to loss of sensory quality when nutritional value of these products is improved, are presented and discussed. There are several studies focused either on the nutritional or sensorial quality of the processed meat products, but more studies with an integration of the two aspects are necessary. Combination of different processing and preservation methods leads to better results of sensory quality; thus, further research in combinations of different techniques are necessary, such that the nutritional value of meat is not compromised. Full article