Journal of Food Safety最新文献

Fresh produce safety is important for consumer health. Intervention technologies that can lessen the pathogen threat and produce contamination is needed. In this research, cold plasma (CP), pulsed light (PL) and their combinations were assessed for inactivating Escherichia coli O157:H7 on Romaine lettuce. The effects of treatment on native microflora and sensory attributes of lettuce was also determined. An inoculum of multiple E. coli O157:H7 strains was employed for this study. Lettuce leaves were spot inoculated and then treated with PL (1–60 s), CP (15–60 s) or their optimized treatment combinations. A 30 s treatment with PL (fluence dose of 31.5 J/cm²), was optimum which provided 2.7 log CFU/g reduction of the pathogen, while 45 s treatment of CP was optimum, that delivered 2.1 log CFU/g log reduction. Combinations of PL and CP treatments were investigated for enhanced inactivation. For PL-CP combination, inoculated lettuce was treated with PL for 30 s followed by 45 s of CP exposure. While for CP-PL combination, treatments sequences were 45 s of CP treatment followed by 30 s PL treatment. Both combination treatments, PL-CP and CP-PL, resulted in synergistic inactivation of E. coli cells with > 5 log reductions of the pathogen. These combination treatments significantly (p < 0.05) reduced native microbiota and slowed their growth during storage. Additionally, treatment effects on lettuce quality was not adversely impacted. PL and CP are both non-aqueous, sustainable technologies. This study demonstrated that integration of PL and CP technology can enhance microbial safety and preserve quality of Romaine lettuce.

This study aimed to elucidate the antibacterial mechanism and antibiofilm activity of ginger essential oil (GEO) against Shewanella putrefaciens. On the basis of minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC), alkaline phosphatase (AKPase), succinate dehydrogenase (SDH), and glucose-6-phosphate dehydrogenase (G6PDH) activities were analyzed to evaluate the damage degree of S. putrefaciens on cell wall and membrane, and the microstructure was observed by scanning electron microscope (SEM) to evaluate the action effect against S. putrefaciens. The results showed that the MIC and MBC of GEO against S. putrefaciens were 27.8125 mg/mL and 55.625 mg/mL, respectively. The surface structures and cell membrane of S. putrefaciens were rigorously damaged by 1 MIC and 2 MIC GEO, leading to the leakage of cellular nucleic acids, protein, and β-galactosidases from the bacterial cells. GEO could not only decrease the biomass of biofilm but also remove mature biofilm. In addition, GEO could reduce the production of exopolysaccharides and extracellular proteins, and could lessen the metabolic activity of biofilm cells. These results demonstrated that GEO exhibited efficient antibacterial characteristics against S. putrefaciens, which could act as a natural antibacterial and antibiofilm agent on the preservation of aquatic products.

Information on the microplastic (MPs) migration, particularly phthalate acid esters (PAEs) in packaged seafood, is limited to a few studies. The aim of this study is to follow the possible migration potential and speed of phthalates in rainbow trout (Oncorhynchus mykiss) fillets stored in vacuum packaging depending on the storage temperature, as well as to determine the polyethylene polymer detection. For this purpose, the fillets were randomly distributed as three pieces in each bag, vacuum-packed, and stored at commonly used temperatures (+4°C and −20°C) for 3 months. On the first day of storage in fillet and packaging materials, in certain periods of storage, the phthalate content in the fillet of each temperature group was determined. It has been determined that the chemical composition of the bag used in the vacuum packaging process is affected by the temperature depending on the storage period, and different polymer types are formed in the packaged material. Ten types of PAEs including diisobutyl phthalate (DIBP), dibutylphthalate (DBP), di-n-pentyl phthalate (DPENP), di-n-hexyl phthalate (DHEXP), butylbenzylphthalate (BBP), di-(2-ethylhexyl)-phthalate (DEHP), dicyclohexyl phthalate (DCHP), di-n-octylphthalate (DNOP), di-iso-nonylphthalate (DINP), and di-isodecylphthalate (DIDP) were recorded in the packaging material and stored fillets. It was determined that the dominant PAE in the fillets were DPENP, and DEHP in the package at all temperature applications and storage periods. The findings help monitor the presence and migration of PAEs in foods and provide a motivating model for adopting the right technologies.

Incidence of foodborne illness due to bacterial contamination of fresh produce continue to exist despite continuous research on processing interventions to mitigate the problem. In this study, we combined atmospheric cold plasma treatments with an antimicrobial solution containing specific organic acids generally recognized as safe (GRAS) by the FDA and tested its antimicrobial efficacy against Salmonella enterica inoculated on tomato surfaces. Tomato surfaces were inoculated with at 5.6 log CFU/g of Salmonella by spotting 0.1 mL of 7 log CFU/ml Salmonella onto the tomato stem scars, and by dipping whole tomatoes into a solution of 7 log CFU/ml Salmonella for 3 min to achieve 4.1 log CFU/g. Antimicrobial efficacy of the organic acid-based sanitizer + cold plasma treatments for 30, 60, 120, 180, and 360 s, were investigated, and significant bacterial inactivation was achieved above 120 s treatments. At 120 s, surviving populations of aerobic mesophilic bacteria recovered on the tomatoes surfaces averaged < 2 logs/g while yeast and mold survival averaged < 1 CFU/g. Treatment combination with this organic acid-based sanitizer + cold plasma for 120 s resulted in a 4.9 log reduction of Salmonella on the stem scar area and a 3.9 log reduction on the smooth peel surface. Similarly, populations of aerobic mesophilic bacteria recovered on treated tomato surfaces averaged < 0.3 log CFU/g. The results of this study indicate that combining an organic acid-based sanitizer with cold plasma treatments for ≥ 120 s can inactivates significant populations of Salmonella to enhance the microbial safety of tomato surfaces designated for fresh-cut salad.

Traditionally methods for assessing mutton quality rely on physical and chemical examination analyses that necessitate precise experimental environment conditions and specialized knowledge, often resulting in the compromise of the sample's structural integrity. To address these challenges, this study explores the application of near-infrared spectroscopy (NIR) as a non-destructive alternative for mutton quality evaluation, leveraging its operational simplicity, rapid analysis capabilities, and minimal requirement for technical expertise. Among various spectral data preprocessing techniques evaluated, multiple scattering correction (MSC) was found to significantly enhance model detection performance. Furthermore, principal component analysis (PCA) combined with the Mahalanobis Distance method was utilized for outlier identification. Finally, a mutton freshness detection model is constructed based on stacking ensemble learning, yielding an impressive accuracy rate of 0.976, outperforming other advanced approaches. In conclusion, our findings establish a robust theoretical framework for the rapid and non-destructive assessment of meat freshness, contributing to advancements in meat quality detection.

The impact of pulsed light treatment (PLT) on natural microbiota and inoculated microbes such as Salmonella Typhimurium, Bacillus cereus, and Aspergillus flavus on red chilies was investigated. Sequential drying did not completely inactivate the aerobic mesophiles and yeast and mold count. Hence, PLT (0.53–2.59 J cm⁻²) was employed as a decontamination technology on red chilies. PLT resulted in 8 log reduction of inoculated microorganisms on chilies at 2.59 J cm⁻². The microbial inactivation kinetics followed Weibull distribution (R² > 0.97) with β value of 1.1, 1.2, and 1.5 for S. Typhimurium, B. cereus, and A. flavus, respectively. Changes in structure and composition of cell components were identified by SEM and FTIR analysis. After PLT, phenolics, antioxidants, flavonoids, and capsaicinoids were better retained but a significant change in ascorbic acid and carotenoid's content was observed. Hence, PL can be a potential technology for decontamination of fresh and dried chilies along with maximum retention of bioactives.

Black bean skin anthocyanins (BBSAs), as by-products of black beans, have not been fully exploited. BBSAs are rich in anthocyanins and have a wide range of health benefits. In this study, the antibacterial and antibiofilm action mode of BBSAs against Vibrio parahaemolyticus (V. parahaemolyticus) was evaluated. The antibacterial and antibiofilm efficiency was evaluated under different conditions, shedding light on their mode of action against V. parahaemolyticus. The results showed that the inactivation efficacy of BBSAs on V. parahaemolyticus was positively correlated with its concentration and incubating time. The MIC value for BBSAs was determined to be 10 μg/mL. The formation of V. parahaemolyticus biofilm was hindered by the presence of the BBSAs, especially at higher concentrations of BBSAs and during the early intervention stage. After exposure to 1 MIC of BBSA, the inhibition rate of biofilm reached 91.94%. The release of cellular components and alterations in membrane morphology indicated that BBSAs can damage the integrity of V. parahaemolyticus cell membrane. Furthermore, BBSAs may interact with membrane proteins, causing a notable conformational change in membrane proteins. HPLC and UPLC-MS analysis confirmed that the major antibacterial compound in BBSAs was Cyanidin-3-O-glucoside (C3G), which can form a stable complex with LolB protein in the outer membrane via hydrogen bonding. This study can provide strong technical support for the accurate control of V. parahaemolyticus and pave the way for the application of natural antibacterial agents in the realm of food-borne bacterial control.

Sprouts are popular due to their high nutritional content, including vitamins, minerals, antioxidants, and enzymes. However, the conditions favorable for sprouting, such as warm and humid environments, are also ideal for the growth of bacteria, including food-borne pathogens. Here, we analyzed the growth and developed predictive models of locally isolated and commercial strains of Salmonella enterica and Listeria monocytogenes in alfalfa sprouts under various constant temperatures, ranging from 5°C to 25°C. Our findings indicated that these pathogens could grow at 5°C in sprouts, albeit with a low growth rate. A rapid increase in concentration occurred at temperatures of 10°C and above. The fitted models demonstrated high performance, with R² values ranging from 0.964 to 0.997 and RMSE values ranging from 0.15 to 0.51, respectively. Based on the fitted values, bias factor (A_f) values varied between 1.01 and 1.06, with all accuracy factor (B_f) values at 1.00. Acceptable prediction zone (APZ) values ranged from 81.8% to 100%. Validation of the models under dynamic temperature conditions for specific strains showed acceptable performance. This study enhances our understanding of S. enterica and L. monocytogenes growth in alfalfa sprouts. The findings of this study could be used to improve the risk assessment of these pathogens in alfalfa sprouts.

Tempe has gained global popularity, with local vegetable oils commonly used for frying. This study evaluates the cooking temperature and stability of five vegetable oils (olive [Oo], palm [Po], canola [Cnlo], sunflower [Sfo], and coconut [Cco]) for deep-frying Tempe, using acid and peroxide values (AV and PV), antiradical activity, and saturated and unsaturated fatty acids. AV, PV, and linolenic acid (LNA) were referenced to international standards for vegetable oil (0.6 mg KOH/g, 10 mEq of oxygen/kg oil, and 2% for AV, PV, LNA respectively). The initial oil temperature was 130°C ± 1°C, with final temperatures between 145.7°C ± 6.8°C at the lowest and 156.8°C ± 13.0°C at the highest, well below existing studies (≥170°C–250°C). Based on AV and PV, Oo, Po, and Cco were stable up to the fourth, fifth, and eighth frying repeat (FR). The PV of Cnlo (10.2 mEq of oxygen/kg oil) and Sfo (15.5 mEq of oxygen/kg oil) exceeded the maximum limit after one use. The Fresh Cnlo LNA (7.35%) was higher than the limit, while the rest of the oils remained lower and stable until the seventh FR. Po exhibited the highest average antiradical activity (85.42% ± 4.63%), followed by Oo (31.01% ± 10.26%), Sfo (27.96% ± 9.67%), Cnlo (21.85% ± 5.71%), and Cco (14.40% ± 3.46%). Cco had the highest saturated fatty acids (SFA), Oo had the highest monounsaturated fatty acids (MUFA), and Sfo had the highest polyunsaturated fatty acids (PUFA). No significant SFA, MUFA, or PUFA changes were observed up to the seventh FR. Trans-fatty acids C18:1n 9T and C18:2n 6T were undetected in fresh and used oil, indicating a unique character in low-temperature deep-frying in domestic settings. This study provides a comprehensive analysis of low-temperature deep-frying of Tempe. It suggests that Oo, Po, Cnlo, Sfo, and Cco were stable to deep-fried Tempe for four, five, zero, one, and eight FR, respectively. Deep-frying Tempe at lower temperatures and for a shorter duration may enhance its health benefits and help retain its flavor.”