ABSTRACT: Although low-moisture foods do not support growth, Listeria monocytogenes can remain viable for extended periods, and long-term survival data for dried fruit systems remain limited. In this study, we evaluated the survival of a three-strain cocktail of L. monocytogenes on dried apple products under different water activities (a w ), storage temperatures, apple cultivars, and product styles during 48 weeks of storage. L. monocytogenes (∼9.0 log 10 CFU/g) was inoculated onto homemade and commercially prepared dried apple slices and equilibrated to a w 0.25 or 0.45 before storage at 22 °C or 4 °C. Across the evaluated conditions, L. monocytogenes populations consistently declined more at 22 °C than at 4 °C. At 22 °C, populations on homemade Granny Smith and Gala slices decreased by ∼7.8- and 5.3-log, respectively, over 48 weeks, compared with reductions of ∼1.9 and 0.9-log, respectively, at 4 °C. Greater population reductions occurred at a w 0.45 than at a w 0.25, particularly at 22 °C (e.g., ∼7.0- vs 4.7-log, respectively, on commercial slices). L. monocytogenes exhibited greater persistence on Gala than on Granny Smith slices. Survival patterns also differed between homemade and commercially prepared products and among product styles. At 22 °C and a w 0.45, reductions on small (1 × 1 cm) commercial slices reached ∼7.0-log, compared with ∼5.0-log on larger (3 × 3 cm) slices. Differences among product styles were less pronounced at 4 °C, where reductions ranged from ∼1.5 to 2.0-log across conditions. Overall, L. monocytogenes demonstrated long-term persistence in dried apple products, with the magnitude of population decline varying with storage temperature, a w , cultivar, preparation method, and product style. These findings provide commodity-specific data relevant to evaluating L. monocytogenes survival in dried fruit products.
Lakshadweep is an archipelago consisting of 35 vibrant coral reef atolls, situated 200-440 km off the south-west coast of India, and dispersed over an area of about 78,000 km2 in the Arabian Sea. Skipjack tuna is one of the major species contributing to the fishery of the island, and a large portion of around 90% of the catch is processed into the traditional smoke-dried product masmin. The processing techniques, which have remained largely unchanged for centuries, involve a sequence of seawater boiling, intensive wood smoking, and solar drying.While smoking methods effectively preserve the fish and impart a unique organoleptic profile highly valued in domestic and international markets, they also introduce significant food safety risks, such as contamination with polycyclic aromatic hydrocarbons (PAHs) formed during the incomplete combustion of wood fuels. Given the potential health risks associated with PAHs, this study evaluated the concentration of 16 priority PAHs in masmin using gas chromatography tandem mass spectrometry (GC-MS/MS) across the islands. The results highlight variations in PAH concentrations across different locations, with Minicoy exhibiting the highest average contamination of total PAH, at 2839.44 ± 15.70 μg kg-1, whereas the Amini samples were contaminated with 224.74 ± 33.93 μg kg-1. The average concentration of benzo [a] pyrene ranged from 2.56 ± 12.29 μg kg-1in Amini samples to 40.87 ± 5.69 μg kg-1 in Minicoy samples. The findings underscore the need for continuous monitoring, especially in the smoking process, to ensure food safety and long-term viability of masmin exports in a global regulatory environment.
This study describes the recall of salt-treated fermented canned anchovies (STFCAs) because of elevated histamine levels and bursting cans. STFCAs are a unique food item in that they are salt treated, fermented and canned, but not thermally processed. Thus, the mesophilic bacteria or bacterial spores, including those that can form histamine, are not destroyed by a thermal treatment. STFCAs have a limited shelf life due to a lack of a thermal inactivation step for the halophilic or proteinaceous bacteria, thus at the end of the shelf life the anchovy fillets can turn mushy in the can. Even though the STFCAs are held in an anaerobic environment during fermentation and after canning, and are not thermally treated, they are protected from Clostridium botulinum and Staphylococcus aureus growth and toxin formation by their elevated salt content and low water activity (aw). The histamine forming bacteria (HFB) growth and sensorial degradation in the STFCAs can be limited with temperature control. We propose STFCAs should be held at or below 10°C (50°F) from manufacturing to consumption. We present calculated No Observed Adverse Effect Level (NOAEL) for STFCAs for the typical United States serving size of 15 g (∼1/2-oz), and discuss our proposed temperature control limit for transportation and storage of STFCAs [< 10°C (50°F)] in light of the lowered defect action level (DAL: 35 ppm) and action level (AL: 200 ppm) for histamine in seafood published by the US Food and Drug Administration in 2024. We suggest including the STFCAs in the regulatory exemption listed in CPG 540.525 (FDA, 2024) for dried fish and fermented fish sauce/paste products that are intended for use only as condiments or as minor flavoring ingredients in other food products.
Raw ready-to-eat beef (yukhoe) is considered a high-risk food because it is consumed without thermal processing, and information on the growth behavior of major foodborne pathogens during chilled distribution remains limited. Therefore, this study evaluated the microbiological safety of yukhoe through retail surveillance and assessment of foodborne pathogen behavior under chilled distribution temperatures (-2 to 10℃). Analysis of 601 retail samples identified enterohemorrhagic Escherichia coli (EHEC) (3.0%), Listeria monocytogenes (2.2%), Clostridium perfringens (1.2%), Staphylococcus aureus (0.7%), and Yersinia enterocolitica (0.3%), whereas Salmonella spp. were not detected. Bacillus cereus was detected in two samples at low levels, both below the regulatory limit of 1,000 colony-forming units per gram. Inoculated yukhoe was stored at 5℃, 7℃, and 10℃ under aerobic and vacuum packaging for 7 days to assess the suitability of chilled distribution temperatures. Pathogen growth was observed at 7℃ and 10℃, whereas no growth occurred at 5℃ under any packaging condition. EHEC was the only pathogen that grew at 7℃ and exhibited the earliest growth among the tested pathogens. At 10℃, EHEC, L. monocytogenes, Y. enterocolitica, and Salmonella spp. proliferated, with greater growth observed under aerobic packaging. By contrast, S. aureus, C. perfringens, and B. cereus did not grow under any tested condition. Overall, microbiological stability strongly depended on storage temperature and packaging atmosphere, with no measurable pathogen growth observed at 5℃ under any packaging condition. These findings highlight the need for strict temperature control and appropriate packaging strategies to ensure the safety of raw, ready-to-eat beef during chilled distribution.
Meat adulteration is a growing concern because it compromises food authenticity, consumer confidence, and ethical or religious preferences. This study aimed to detect goat and horse DNA in meat marketed as goat meat in Addis Ababa, Ethiopia, using mitochondrial cytochrome oxidase I (COI)-based polymerase chain reaction (PCR). A cross-sectional study was conducted from August 2025 to March 2026. A total of 427 raw meat samples were collected from licensed butcheries using a multistage random sampling approach. Genomic DNA was extracted using phenol-chloroform and salting-out methods and analyzed by conventional PCR using species-specific primers targeting the mitochondrial COI gene. A structured questionnaire was administered to assess meat-handler awareness of meat adulteration. Of the 427 samples analyzed, 368 (86.2%) were positive for goat DNA, whereas 5 (1.2%) were positive for horse DNA, indicating the presence of undeclared horse-derived genetic material. No amplification was detected in 54 (12.6%) samples, which were classified as inconclusive. Because only five samples were positive for horse DNA, statistical assessment of factors associated with horse DNA detection was not considered sufficiently reliable, and questionnaire findings are therefore presented descriptively. Awareness of meat adulteration was moderate, although the ability to identify adulterated meat by visual inspection alone was limited. Because the assay was qualitative, horse DNA could be detected but not quantified. These findings demonstrate the utility of COI-based PCR for meat species identification and support strengthening surveillance, laboratory capacity, and food authenticity monitoring systems in Ethiopia.
