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Green papaya salad or Som Tum is the most popular spicy mixed salads in Thailand due to its unique rich flavor. Green papaya salad dressing (GPSD) is made from various ingredients such as fresh chili pepper, fresh garlic, rind tamarind, fish sauce and lime oil, including the limitation in controlling the taste and flavor of salad dressing and its poor shelf-life. In this study, a convenient ready-to-eat GPSD was developed. Hurdle technology was applied to extend shelf-life of the GPSD based on monitoring of microbial contamination and food pathogens throughout the process. Hurdle technology able to decrease total plate count (TPC) from 5.6 ± 0.2 to 1 ± 0.3 log CFU/g and yeast and mold (Y&M) from 4.2 ± 0.3 to <1 log CFU/g. After 12 weeks of storage at 5 ± 2 °C, slightly increase of TPC was detected as 1.5 ± 0.2 log CFU/g and no changes were found for Y&M and other pathogens. At week 12, GPSD stored at 32 ± 2 °C was found to have higher TPC and Y&M (3.7 ± 0.3 and 2.4 ± 0.3 log CFU/g, respectively). Therefore, a combination of hurdles that combines low a w , low pH, heat treatment, low temperature after hot filling, and chilled storage could extend the shelf-life of GPSD with satisfy sensorial test result and be suitable for minimally processed salad dressing. • Hurdle effect in preparations was significantly reduced TPC and Y&M of GPSD. • Hurdle effects were successfully extended shelf-life of GPSD up to 12 weeks. • Hurdle technology applied with GPSD did not alter the taste of final product. • Hurdles offer industry applicable procedure to minimally processed salad dressing. [ABSTRACT FROM AUTHOR] more...

Vegetables that can be eaten raw in salads are considered at higher risk for contamination by foodborne pathogens and pesticide residues. In this study fresh leafy green vegetables, both pre-cut and uncut, were sampled at retail in all 20 Italian regions and tested for pathogens and pesticide residues contamination. Both in pre-cut and in uncut vegetables 1.00% of samples tested positive for pathogens investigated. Pesticide residues were detected in 53.33% of samples, pre-cut vegetables were more often contaminated (59.06%) than uncut vegetables (47.68%). Samples tested positive from one (monoresidual samples, 27.33%) to seven chemical compounds (multiresidual samples, 26.00%). Maximum Residual Levels (MRL) established by European legislation were exceeded in two multiresidual samples of uncut romaine lettuce (overall non-compliant prevalence 0.67%). A few samples resulted non-compliant for MRL or contaminated by pathogens. Nevertheless in more than half of the samples analysed pesticide residues were found; furthermore vegetables encompassed in this survey are eaten raw and process does not include any effective microbial elimination step. These findings can suggest that public health risk remains, especially regarding pre-cut vegetables. [ABSTRACT FROM AUTHOR] more...

Raw, ready-to-eat (RTE) seafood products have become increasingly popular globally, but they are vulnerable to species substitution and mislabeling. DNA barcoding allows for fish species identification by extracting, amplifying, and sequencing a standardized gene target. A wide variety of fish products have been studied with DNA barcoding, but little investigation of ceviche and poke has occurred in the United States. Sushi is known to be a target of mislabeling but has not been extensively studied in Orange County, CA. The objective of this study was to investigate species substitution and mislabeling of sushi, poke, and ceviche dishes sold at restaurants in Orange County, CA. A total of 105 raw, RTE seafood products were collected, including sushi (n = 35), poke (n = 35), and ceviche (n = 35). All samples were sequenced with DNA barcoding or mini-barcoding. The identified species were compared against the menu names, verbal declarations by restaurant staff, and the Food and Drug Administration (FDA) Seafood List to verify whether acceptable market names were used for each product. Of the 103 samples identified with DNA barcoding, species substitution was detected at a rate of 23.3% and unacceptable market names were found in 45.6% of samples. Overall, 63.1% of samples had some form of mislabeling. When the mislabeling rates were divided based on product category, ceviche had the highest overall mislabeling rate (85.3%), followed by poke (61.8%), and sushi (42.9%). Mislabeling of ceviche and poke was primarily driven by the use of unacceptable market names, while species substitution was more common in sushi dishes. These rates reveal widespread mislabeling among raw, RTE seafood products and suggest the need for outreach efforts to ensure proper labeling of fish using acceptable market names, as well as further research into mislabeling within the raw, RTE seafood supply chain. • Ceviche, poke, and sushi were examined for species substitution and mislabeling. • Overall, 63.1% of samples had unacceptable market names and/or species substitution. • The overall mislabeling rates were 85% for ceviche, 62% for poke, and 43% for sushi. • Unacceptable market names were most common in ceviche, followed by poke and sushi. • Species substitution was most common in sushi, followed by ceviche and poke. [ABSTRACT FROM AUTHOR] more...

Modified atmosphere packaging (MAP) based on carbon dioxide (CO 2 ) – nitrogen (N 2 ) gas mixtures has been applied to maintain the safety and quality of ready-to-eat (RTE) meat products. The use of argon (Ar) gas as a supplement to CO 2 –N 2 mixtures or as substitute for N 2 is a current approach to enhance the effectiveness of MAP. As there is limited information on the effect of Ar MAP on the growth behaviour or the survival of pathogenic bacteria in RTE foods, the aim of the present study was to assess the influence of Ar in MAP on the growth of Listeria monocytogenes and Escherichia coli strains under different conditions. For this purpose, a CO 2 –N 2 (20:80) atmosphere was compared with a CO 2 –N 2 –Ar (30:30:40) and CO 2 –Ar (30:70) atmosphere based on the assessment of bacterial growth (δ) on a gelatin-agar medium and ham. Additionally, a shelf life monitoring study was performed to evaluate the effect of these treatments on the background microflora of ham. The findings suggest that under the CO 2 –N 2 MAP the product matrices supported the growth (δ > 0.5 log CFU g −1 ) of L. monocytogenes throughout an observation period of 21 days at 4 ± 2 °C. On the contrary, both MAP containing Ar were equally able to reduce the δ below 0.5 log CFU g −1 . In this regard it was irrelevant whether L. monocytogenes was inoculated in depth (per slice) or at the surface (top slice) of the ham. Regarding the influence of the different gas atmospheres on E. coli all gas mixtures applied had the capacity to reduce the δ of E. coli below −0.5 log CFU g −1 . Further, shelf-life extension could not be managed with the gas atmospheres considered. [ABSTRACT FROM AUTHOR] more...

Listeria monocytogenes is a psychrotrophic foodborne pathogen that has been isolated from ready-to-eat meat and poultry products (RTE meats). The purpose of this study was to quantify lactate and acetate levels in retail RTE meats that had been tested in a previous study for the presence of L. monocytogenes to correlate the occurrence of L. monocytogenes to the acid levels. Products were extracted after blending 50 g of each sample with de-ionized water, and the extracts were quantified for lactate and acetate using HPLC. In general, the concentrations of both acids in samples varied with product types and manufacturers (p < 0.05). The mean concentrations of lactate and acetate ranged from 10.71 to 23.03 mg/g (1.07–2.30%) and 0.66–1.56 mg/g (0.066–0.156%), respectively. The mean concentrations of lactate and acetate in L. monocytogenes -positive samples were 1.13–24.05 mg/g (0.11–2.4%) and 0–5.74 mg/g (0–0.574%), respectively. Results of this study indicate that RTE meats containing low levels of lactate were more likely to be positive for L. monocytogenes while samples with higher concentrations of lactate and acetate were less likely to be positive for the pathogen. Therefore, the addition of lactate and acetate as antimicrobials is helpful as part of an overall Listeria control program. However, a rigorous sanitation and an effective HACCP program are also essential for control of Listeria . [ABSTRACT FROM AUTHOR] more...

Fresh-cut fruits in ready-to-eat packaging are convenient healthy snacks that can be composed of one type of fruit or a mixture of different fruits to attract consumer's attention. However, to date, no studies have been performed to determine whether fruit mixing could impair fruit quality traits or their shelf-life. Here, we aimed at evaluating quality and hormonal changes in unmixed and mixed cut fruits in packaging of kiwis, mangoes, oranges and pineapples over a 6-day period in cold storage to (i) determine endogenous events compromising cut fruit quality and (ii) assess whether fruit mixing could have an impact in their storage. Results showed fruit cutting led to rapid losses in water content and firmness, while respiration rates increased. Fruit mixing altered several quality parameters, delaying firmness loss in mangoes, oranges and pineapples, and increasing ratios of sugars by acids (TSS/TA) over time. Fruit mixing increased vitamin C contents in mangoes and oranges but decreased total phenols accumulation in oranges and pineapples. Kiwis had an opposite pattern of vitamin C accumulation, with unmixed kiwis having the highest ascorbate contents, while no significant differences were found for total phenols. Increased abscisic acid contents were also found in mangoes, oranges and pineapples of unmixed packaging, and kiwis displaying a much lower accumulation compared to the other fruits. Other phytohormones were also affected by fruit composition, suggesting an active involvement in fruit quality regulation. In conclusion, fruit composition in ready-to-eat packaging is an important factor determining the final quality and shelf-life of cut fruits. • Fruit cutting effects on quality properties and antioxidant composition in ready-to-eat packaging were partially improved by fruit mixing. • Mangoes, oranges and pineapples considerably benefit from the fruit mix, retaining higher firmness and improving their ascorbate contents. • Abscisic acid, jasmonic acid, gibberellins and cytokinins were actively involved in the preservation of quality traits and antioxidants in the mix. • Fruit shelf-life and quality traits can be modulated considering the fruit packaging composition and its effects on the hormonal balance. [ABSTRACT FROM AUTHOR] more...

Abstract: Tofu is a popular food choice for people with health concerns, especially vegetarians. In this study, the survival and growth of Listeria monocytogenes was investigated after it had been inoculated into various tofu products. Three kinds of pre-packaged tofu products were purchased, and a mixture of four strains of L. monocytogenes was injected into these products before storage treatment at either 4–7 °C or 22 °C. During storage treatment, the inoculated L. monocytogenes (starting at the level of approximately 3 log CFU/g) competed to grow among the background microflora that is inherently present in the tofu samples. The L. monocytogenes flora reached the concentrations of 7.1–7.9 log CFU/g after 24 days at 4–7 °C treatment or 6.9–7.5 log CFU/g after 48 h at 22 °C treatment. Nevertheless, compared to other single species of the indigenous microflora within the three kinds of tofu samples, the inoculated L. monocytogenes strains were the numerically dominant population. These results indicate that L. monocytogenes contamination in tofu products at the manufacturing process or at the retail level poses a potential risk to human health. [ABSTRACT FROM AUTHOR] more...

Abstract: The effect of gamma irradiation for inactivating the pathogens inoculated into the ready-to-eat Kimbab, steamed rice rolled by dried laver, was investigated. The pathogens used were Salmonella Typhimurium, Escherichia coli, Staphylococcus aureus and Listeria ivanovii which are important for public health. The growth of four test organisms inoculated (about 106–107 CFU/g) into the Kimbab were sustained by an irradiation treatment during 24h of storage regardless of the temperature at 10, 20 and 30°C. Four pathogen inoculated into Kimbab decreased 2–3log CFU/g by 1kGy treatment and was not detected after 3kGy. The D 10 value of pathogens inoculated into the Kimbab were 0.31–0.44kGy among the four organisms. This study indicated that a low dose irradiation can maintain microbial safety for ready-to-eat Kimbab, steamed rice rolled by dried laver. [Copyright &y& Elsevier] more...

Abstract: The ability of Listeria monocytogenes to survive and grow at refrigeration temperature in some ready to eat (RTE) poultry products is a public health concern. The inhibitory effect of clove oil (1% and 2%, v/w) applied to the surface of RTE chicken frankfurters was determined on seven strains of L. monocytogenes inoculated at low (102–103 cfu/g) or high cell numbers (104–106 cfu/g), and stored at 5°C for 2 weeks or at 15°C for 1week. All strains of L. monocytogenes survived and grew on control frankfurters at 5°C and 15°C but growth was inhibited under both storage conditions in the presence of either 1% or 2% clove oil. Depending on the sensory considerations, the addition of clove oil to frankfurters may be an effective strategy to control L. monocytogenes in chicken frankfurters. [Copyright &y& Elsevier] more...

The global demand for home meal replacement (HMR) products has been increasing because of changing consumer behavior toward convenience foods. Although the quality of food products is the most important factor in the decision to purchase, packaging also has a decisive influence on customer choice. Therefore, the importance of packaging technology in the HMR industry has increased significantly. Depending on the packed food requirements, appropriate packaging technology can provide significant benefits to both producers and consumers. Active packaging technology, such as modified atmosphere and antimicrobial packaging, has received considerable attention because of its potential to prolong the product shelf-life, while intelligent packaging technology such as colorimetric indicators and radio-frequency identification labels can monitor the real-time condition of the packed food and communicate with consumers. Packaging technology keeps evolving in response to the growing challenges from industry and society. This review aims to provide information about innovative and commercialized packaging technologies applied to HMR products. Recognized packaging technologies have been discussed, including easy-peel adhesive, microwave susceptor, and intelligent packaging. In addition, the influence of external factors, such as modern consumer behavior, recent global issues such as circular economy and pandemics, and emerging technology on packaging trends, are evaluated and discussed for future development. • Shifts in consumer preferences for convenience foods have increased global demand for HMR products. •Packaging is critical for quality control of HMR products. •Consumers benefit from advanced materials and functional packaging. •Intelligent packaging is becoming more prevalent in chilled and frozen foods. •Greener and safer food packaging is being considered due to global issues. [ABSTRACT FROM AUTHOR] more...