Assessment of Hygiene Management Practices and Comparative Analysis of Regulatory Frameworks for Shared Kitchens across Different Countries.

Shared kitchens, where users share kitchen space, are becoming popular worldwide due to the economic cost savings of startup businesses. This study conducted monitoring of microbial and chemical hazards from prepared foods and the environment of shared kitchen facilities, surveyed shared kitchen operators, and compared shared kitchen regulations between Korea and other countries. The monitoring results indicate that the hygiene status of the facilities and the microbial and chemical hazards in the prepared foods were all within the standard specifications, showing significantly lower levels compared to regular restaurants (p < 0.05). In particular, concurrent-use and time-division types of open shared kitchens showed significantly lower levels of both hazards than separated-individual kitchens. Survey results of hygiene inspection also confirmed better hygiene management in concurrent-use and time-division types of open shared kitchens in Korea. However, more frequent cleaning and disinfection, hygiene inspections, and training are high economic burdens in the operation of shared kitchens compared to regular restaurants. Moreover, mandatory insurance subscriptions, the operator's responsibility in hygiene-related incidents, and high operational costs collectively challenge shared kitchens' competitiveness in the food service market. Critical reassessments of regulations utilizing the benefits of shared kitchens are needed to promote a safe dining culture and the growth of shared kitchen startup businesses.

Gelatin/poly(vinyl alcohol)-based functional films integrated with spent coffee ground-derived carbon dots and grapefruit seed extract for active packaging application.

Nanoparticles are attractive, functional additives with great potential to be applied in biomaterial and food packaging. However, these particles are not soluble in water, thus limiting their widespread application. Here, we report a facile fabrication of carbon dots (CDs) using the spent coffee ground as the carbon source through a hydrothermal method. The CD was added to the gelatin/poly(vinyl alcohol) (Gel/PVA) film and grapefruit seed extract (GSE) to prepare multifunctional packaging films. The functional films' physiochemical and functional properties and packaging application were investigated. The composite film showed good UV protection properties with a slight decrease in transparency. The composite film containing CD/GSE showed strong antioxidant activity, scavenging >38 % DPPH and 100 % ABTS radicals. The film also exhibited significant antibacterial activity against the foodborne pathogens Listeria monocytogenes and Escherichia coli, completely eradicating the growth of these bacteria within 9 h of exposure. The CD/GSE-incorporated Gel/PVA films were used for pork packaging. The films were able to enhance the pork shelf life by reducing the L. monocytogenes bacterial growth in meat by 2 Log CFU/mL lower than the control wrapping film. The multifunctional Gel/PVA films are expected to be used for the active packaging of meat products.

Effect of Probiotic Lactic Acid Bacteria (LAB) on the Quality and Safety of Greek Yogurt.

Greek yogurt is a strained yogurt with a high protein content that brings nutritional benefits. To enhance the functional benefits of Greek yogurt, Greek yogurt was prepared with various combinations of probiotic lactic acid bacteria (LAB) (Streptococcus thermophilus, Lactobacillus bulgaricus, Lactobacillus gasseri BNR17, and Lactobacillus plantarum HY7714). Effects of probiotic LAB on quality, sensory, and microbiological characteristics of Greek yogurt were then compared. Among samples, Greek yogurt fermented by S. thermophilus and L. bulgaricus showed the highest changes of pH and titratable acidity during 21 d of storage at 4 °C. Greek yogurt fermented with L. plantarum HY7714 had a higher viscosity than other samples. Greek yogurt fermented with S. thermophilus, L. bulgaricus, L. gasseri BNR17, and L. plantarum HY7714 showed superior physicochemical properties and received the highest preference score from sensory evaluation among samples. Overall, the population of enterohaemorrhagic Escherichia coli (EHEC) was more effectively reduced in Greek yogurt fermented with probiotic LAB than in commercial Greek yogurt during storage at 4, 10, and 25 °C. Thus, the addition of L. gasseri BNR17 and L. plantarum HY7714 as starter cultures could enhance the microbial safety of Greek yogurt and sensory acceptance by consumers.

Synthesis of Fully Deacetylated Quaternized Chitosan with Enhanced Antimicrobial Activity and Low Cytotoxicity.

Fully deacetylated quaternary chitosan (DQCTS) was prepared by replacing the carboxyl group of chitosan with a quaternary ammonium salt. The DQCTS was characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), and nuclear magnetic resonance (NMR). The antimicrobial activity of DQCTS was evaluated using the minimum inhibitory concentrations (MIC) methods and time-kill assay. DQCTS exhibited strong antibacterial and antifungal activity against Staphylococcus aureus, Escherichia coli O157: H7, Candida albicans, and Aspergillus flavus. Especially, the antifungal activity against C. albicans of DQCTS was greatly improved at 15.6 µg/mL of MIC and 31.3 µg/mL of minimum fungicidal concentration (MFC). Expression levels of virulence genes of microorganisms were also significantly decreased by DQCTS treatment, and the risk of virulence of microorganisms might be decreased. The result of the cytotoxic effect of DQCTS on human skin cells (HaCaT cells) indicated that the cytotoxicity of DQCTS on HaCaT cells was nearly non-toxic at 50 µg/mL. The DQCTS, with strong antimicrobial and low toxicity, has a high potential for use in functional food packaging and biomedical applications.

Transposition of insertion sequences by dielectric barrier discharge plasma and gamma irradiation in the radiation-resistant bacterium Deinococcus geothermalis.

Insertion sequences (ISs) of the radiation-resistant bacterium Deinococcus geothermalis are transposed into other loci by oxidative stress through hydrogen peroxide treatment. Gamma irradiation and dielectric barrier discharge (DBD) plasma radiation are known to produce a variety of oxidative stress agents such as reactive oxygen species and reactive nitrogen species. Therefore, to determine whether the transposition of ISs was induced in D. geothermalis by both gamma irradiation and DBD plasma radiation, we selected non-pigmented mutants with disrupted target genes encoding carotenoid biosynthesis enzymes such as a phytoene synthase (dgeo_0523) and a phytoene desaturase (dgeo_0524). Different DNA-binding protein-deficient mutants exhibited novel transposition of ISs. Dps (dgeo_0257), OxyR (dgeo_1888), and the LysR (dgeo_2840) family regulator, in addition to cystine importer-disrupted and -overexpressed mutants (dgeo_1986-87 and dgeo_1985R) and wild-type D. geothermalis were tested in this study. Active IS transposition was not detected in two wild-type control species (Deinococcus radiodurans and Deinococcus radiopugnans) after phenotypic selection in gamma irradiation. Our finding demonstrated that gamma irradiation triggers the transposition of particular IS elements, especially ISDge2 and ISDge3 of the IS1 family, ISDge5 of the IS701 family, and ISDge6 of the IS5 family in wild-type strain and the Δdgeo_0257, Δdgeo_1986-87, Δdgeo_1985R, and Δdgeo_2840 mutants. Furthermore, DBD plasma radiation triggered the transposition of ISDge11 of the IS4 family in the wild-type strain; ISDge6 of the IS5 family on Δdgeo_0257, Δdgeo_1888 and Δdgeo_2840; ISDge5 of the IS701 family on Δdgeo_0257 strain.

Quantitative Microbial Risk Assessment of Listeria monocytogenes and Enterohemorrhagic Escherichia coli in Yogurt.

Listeria monocytogenes can survive in yogurt stored at a refrigeration temperature. Enterohemorrhagic Escherichia coli (EHEC) has a strong acid resistance that can survive in the yogurt with a low pH. We estimated the risk of L. monocytogenes and EHEC due to yogurt consumption with @Risk. Predictive survival models for L. monocytogenes and EHEC in drinking and regular yogurt were developed at 4, 10, 17, 25, and 36 °C, and the survival of both pathogens in yogurt was predicted during distribution and storage at home. The average initial contamination level in drinking and regular yogurt was calculated to be -3.941 log CFU/g and -3.608 log CFU/g, respectively, and the contamination level of both LM and EHEC decreased in yogurt from the market to home. Mean values of the possibility of illness caused by EHEC were higher (drinking: 1.44 × 10-8; regular: 5.09 × 10-9) than L. monocytogenes (drinking: 1.91 × 10-15; regular: 2.87 × 10-16) in the susceptible population. Both pathogens had a positive correlation with the initial contamination level and consumption. These results show that the foodborne illness risk from L. monocytogenes and EHEC due to yogurt consumption is very low. However, controlling the initial contamination level of EHEC during yogurt manufacture should be emphasized.

Effect of Quinoa (Chenopodium quinoa Willd.) Starch and Seeds on the Physicochemical and Textural and Sensory Properties of Chicken Meatballs during Frozen Storage.

The effects of starch (corn and quinoa) and quinoa seeds on chicken meatballs' physicochemical, textural, and sensory properties were investigated during frozen storage. The chicken meatballs were prepared with corn starch (CS), quinoa starch (QS), quinoa seeds (Q), and combinations of corn starch and quinoa seeds (CS-Q), and quinoa starch and quinoa seeds (QS-Q), which were subjected to five freeze-thaw (F-T) cycles of temperature fluctuation conditions during frozen storage. Regardless of the type used (CS or QS), adding starch resulted in fewer cooking, drip, and reheating losses in chicken meatballs during frozen storage. The values of the hardness, gumminess, and chewiness of chicken meatballs with CS or QS were half those of chicken meatballs without starch, indicating that the addition of starch inhibited the change in the meatballs' texture. The total volatile basic nitrogen (TVB-N) and thiobarbituric acid reactive substance (TBARS) values were progressive but did not dynamically increase during five F-T cycles. Chicken meatballs containing CS-Q or QS-Q showed significantly lower TBARS values than those with CS, QS, or Q after five F-T cycles. Adding quinoa seeds significantly increased the antioxidant activity and the chewiness of meatballs (p < 0.05) compared with starch only. The addition of the combination of QS-Q to chicken meatballs increased the values of taste, texture, and overall acceptability, indicating that quinoa starch and seeds may be introduced as premium ingredients to frozen meat products.

Lactic acid bacteria starter in combination with sodium chloride controls pathogenic Escherichia coli (EPEC, ETEC, and EHEC) in kimchi.

Kimchi is one of the primary sources of high sodium content in the Korean diet. Low-sodium kimchi is commercially manufactured to minimize the health effects of high salt. We investigated the influence of lactic acid bacteria (LAB) as starter culture in combination with 1% or 2.5% salt on the survival of pathogenic Escherichia coli and physicochemical properties of kimchi during fermentation at 10 °C and 25 °C. Among ten strains of LAB isolated from kimchi, Leuconostoc mesenteroides (KCTC 13374) and Lactobacillus plantarum (KCTC 33133) exhibited antimicrobial activities against pathogenic E. coli (EPEC, ETEC, and E. coli O157:H7) and strong tolerance to low pH (2 and 3) and 0.3% bile salts. Thus, L. mesenteroides and L. plantarum were used as starter cultures for kimchi that contained 1% and 2.5% salt. All pathogenic E. coli strains survived in kimchi regardless of starter cultures or salt concentration for over 15 days at 10 °C, but they died off within 4 days at 25 °C. Survival of pathogenic E. coli was better in naturally fermented kimchi (titratable acidity:0.65%) than kimchi fermented with starter cultures (titratable acidity:1.0%). At 10 °C, the average delta value of E. coli O157:H7 (16.15 d) was smaller than those of EPEC (20.76 d) and ETEC (20.20 d) in naturally fermented kimchi. Overall, survival ability of E. coli O157:H7 was lower than EPEC and ETEC, although differences were not significant. Reduced salt concentration from 2.5% to 1% in kimchi did not affect the growth of LAB and the fermentation period. Pathogenic E. coli died at a faster rate in kimchi fermented with starter cultures and 1% salt than in naturally fermented kimchi with 2.5% salt.

Combined Hurdle Technologies Using UVC Waterproof LED for Inactivating Foodborne Pathogens on Fresh-Cut Fruits.

This study investigated the combined bactericidal efficacy of slightly acidic electrolyzed water (SAEW), fumaric acid (FA), and ultravioletC waterproof light-emitting diodes (UVC W-LED) for the control of Staphylococcus aureus and Listeria monocytogenes in fresh-cut fruits. Cherry tomato, grape, apple, and pineapple were inoculated with S. aureus and L. monocytogenes and then washed with 30 ppm SAEW containing 0.5% FA in a container equipped with two UVC W-LEDs. Behaviors of S. aureus and L. monocytogenes and quality properties of fresh-cut fruits were monitored after storage at 10 °C and 15 °C for 7 days. The most effective reductions of S. aureus (1.65 log CFU/g) and L. monocytogenes (2.63 log CFU/g) were observed in the group with the combined treatment of SAEW + FA and UVC W-LED. At 10 °C and 15 °C, populations of both pathogens in the combined treatment group were lower than those in a control. Combined treatment showed no negative effect on moisture retention in the fruit. Moreover, visual changes were less significant than in the control. These results demonstrate that the combined treatment can improve the microbial safety and the quality of fruits. If it is properly used in the sanitizing step of the fresh produce industry, a positive effect can be expected.

Effects of Combined Aerosolization with Ultraviolet C Light-Emitting Diode on Enterohemorrhagic Escherichia coli and Staphylococcus aureus Attached to Soft Fresh Produce.

Washing soft fresh produce such as strawberries, baby leaves, and sliced onions with sanitizing agents is challenging due to their fragile texture. Thus, treatments like aerosolization using slightly acidic electrolyzed water (SAEW) and ultraviolet C light-emitting diode (UVC LED) irradiation may be good alternatives. In the present study, the reduction effects of a combined treatment of aerosolization using SAEW and UVC LED irradiation on enterohemorrhagic Escherichia coli (EHEC) and Staphylococcus aureus attached to strawberries, baby leaves, and sliced onions were investigated. The behaviours of EHEC and S. aureus, moisture loss, colour measurement, and visual appearance were also analyzed at 10 and 15 °C for 7 days. The reduction effect of the combined treatment with 100 SAEW and UVC LED was higher (0.53-0.92 log CFU g-1) than a single aerosolization treatment (0.11-0.41 log CFU g-1), regardless of samples or pathogens. A greater effect on EHEC and S. aureus reduction was observed in strawberries (0.74 and 0.92 log CFU g-1) than in baby leaves (0.62 and 0.53 log CFU g-1) and sliced onions (0.55 and 0.62 log CFU g-1). The combined treatment further reduced the EHEC and S. aureus populations in strawberries during 7 days of storage at 10 and 15 °C. However, the EHEC and S. aureus populations were maintained in baby leaves and sliced onions at 10 °C for 7 days. Additionally, the greatest effect on the maintenance of colour and appearance was obtained in the combined treatment. Since the combined treatment reduces EHEC and S. aureus populations and preserves visual quality, it could be expected to extend the shelf life of soft fresh produce at the retailer stage of the supply chain.

Control Measures of Pathogenic Microorganisms and Shelf-Life Extension of Fresh-Cut Vegetables.

We investigated the combined effect of using slightly acidic electrolyzed water (SAEW), ultrasounds (US), and ultraviolet-C light-emitting diodes (UV-C LED; 275 nm) for decreasing pathogenic Escherichia coli and Staphylococcus aureus (SEA) in fresh-cut vegetables, including carrots, celery, paprika, and cabbage. Survival of pathogenic E. coli and SEA and quality properties of fresh-cut vegetables at 5 and 15 °C for 7 days were also investigated. When combined treatment (SAEW + US + UV-C LED) was applied to fresh-cut vegetables for 3 min, its microbial reduction effect was significantly higher (0.97~2.17 log CFU/g) than a single treatment (p < 0.05). Overall, the reduction effect was more significant for SEA than for pathogenic E. coli. At 5 °C, SAEW + US and SAEW + US + UV-C LED treatments reduced populations of pathogenic E. coli and SEA in all vegetables. At 15 °C, SAEW + US + UV-C LED treatment inhibited the growth of both pathogens in carrot and celery and extended the shelf life of fresh-cut vegetables by preventing color changes in all vegetables. Although the effects of treatments varied depending on the characteristics of the vegetables and pathogens, UV-C LED can be suggested as a new hurdle technology in fresh-cut vegetable industry.

Selective Butyrate Esterase Probe for the Rapid Colorimetric and Fluorogenic Identification of Moraxella catarrhalis.

Clinical identification of the pathogenic bacterium Moraxella catarrhalis in cultures relies on the detection of bacterial butyrate esterase (C4-esterase) using a coumarin-based fluorogenic substrate, 4-methylumbelliferyl butyrate. However, this classical probe may give false-positive responses because of its poor stability and lack of specificity. Here, we report a new colorimetric and fluorogenic probe design employing a meso-ester-substituted boron dipyrromethene (BODIPY) dye for the specific detection of C4-esterase activity expressed by M. catarrhalis. This new probe has resistance to nonspecific hydrolysis that is far superior to the classical probe and also selectively responds to esterase with rapid colorimetric and fluorescence signal changes and large "turn-on" ratios. The probe was successfully applied to the specific detection of M. catarrhalis with high sensitivity.

Comparative antibacterial and antifungal activities of sulfur nanoparticles capped with chitosan.

The antimicrobial activity of sulfur nanoparticles (SNPs) was compared with elemental sulfur and sulfur-containing salts (sodium thiosulfate and sodium metabisulfite) against bacteria (Escherichia coli, Staphylococcus aureus) and fungi (Aspergillus flavus, Candida albicans) using the paper disc, broth microdilution, and time-kill assay methods. The results of the paper disc and MIC tests showed stronger antimicrobial activity of SNPs compared to the elemental sulfur and sulfur-containing salts. SNPs showed more potent activity against bacteria than fungi. Among the test microorganisms, E. coli (Gram-negative) was the most susceptible to SNPs, followed by S. aureus (Gram-positive), C. albicans (yeast), and A. flavus (mold). Scanning electron micrographs of microorganisms treated with SNPs showed different cell disruption patterns depending on the type of microorganisms.

A risk assessment study of Bacillus cereus in packaged tofu at a retail market in Korea.

The objective of the study was to conduct a quantitative microbial risk assessment of Bacillus cereus for packaged tofu in Korea. Packaged tofu, including soft and firm tofu from six retail markets in Korea, were monitored to determine the initial contamination level of B. cereus. Predictive growth and survival models were developed to predict the change in B. cereus populations as a function of time and temperature (4-45 °C) from market to home. B. cereus was detected in 11 (12.9%) samples among 85 samples purchased at retail markets, and the average contamination level was 1.84 log CFU/g. Growth of B. cereus in tofu was observed at a temperature above 11 °C. The probability risk of B. cereus diarrheal illness due to packaged tofu consumption at the retail market is 1.0 × 10-4 per person per day. Key risk factors at the retail market and home are storage temperature and time of packaged tofu.

Analysis of saponin composition and comparison of the antioxidant activity of various parts of the quinoa plant (Chenopodium quinoa Willd.).

Quinoa plant is a valuable food crop because of its high nutritional and functional values. Total saponin content, sapogenins, polyphenol, and flavonoid contents and antioxidant activities were analyzed in various parts of quinoa plants, including sprout, seeds, bran, pericarp, leave, stem, and root. Quinoa seeds (QS) had significantly higher sapogenin content than quinoa stem (QT), quinoa leaves (QL), and quinoa roots (QR). Quinoa saponin was mainly composed of phytolaccagenic acid. Quinoa root (QR) had the highest amount of total saponin (13.39 g 100 g-1), followed by quinoa bran. The highest total phenolic content (30.96 mg GAE 100 g-1) and total flavonoid content (61.68 mg RE 100 g-1) were observed in quinoa root extract and 1-month-old sprout extract, respectively. Quinoa sprouts showed better antioxidant activity than fully grown parts of the quinoa plant. Overall, root and sprout had a higher antioxidant capacity compared to other parts of the quinoa plant, suggesting the potential use of quinoa root and sprout as a nutraceutical ingredient in the health food industry.

Risk Comparison of the Diarrheal and Emetic Type of Bacillus cereus in Tofu.

We investigated the ability of biofilm formation, survival, and behavior of diarrheal and emetic Bacillus cereus vegetative cells and spores in tofu. Both diarrheal and emetic B. cereus did not proliferate at a temperature below 9 °C in tofu. However, the emetic B. cereus grew faster than diarrheal B. cereus at 11 °C and had better survival ability at low temperatures. Both diarrheal and emetic B. cereus were able to form a biofilm on stainless steel. These biofilm cells were transferred to tofu in live state. The transferred biofilm cells could not grow at a temperature below 9 °C but grew over 11 °C, like planktonic cells. B. cereus contamination in tofu at a high concentration (>6 logs CFU/g) was not entirely killed by heating at 80, 85, or 90 °C for 2 h. Spores and emetic B. cereus had higher resistance to heat than vegetative cells and diarrheal B. cereus, respectively.

Quantitative Microbial Risk Assessment for Campylobacter jejuni in Ground Meat Products in Korea.

This study evaluated Campylobacter jejuni risk in ground meat products. The C. jejuni prevalence in ground meat products was investigated. To develop the predictive model, survival data of C. jejuni were collected at 4°C-30°C during storage, and the data were fitted using the Weibull model. In addition, the storage temperature and time of ground meat products were investigated during distribution. The consumption amount and frequency of ground meat products were investigated by interviewing 1,500 adults. The prevalence, temperature, time, and consumption data were analyzed by @RISK to generate probabilistic distributions. In 224 samples of ground meat products, there were no C. jejuni-contaminated samples. A scenario with a series of probabilistic distributions, a predictive model and a dose-response model was prepared to calculate the probability of illness, and it showed that the probability of foodborne illness caused by C. jejuni per person per day from ground meat products was 5.68×10-10, which can be considered low risk.

Quantitative prevalence and characterization of Campylobacter from chicken and duck carcasses from poultry slaughterhouses in South Korea.

The objective of this study was to assess the quantitative prevalence, antibiotic resistance, and molecular subtyping pattern of Campylobacter isolates from chicken and duck products from poultry slaughterhouses in South Korea. A total of 240 chicken (n = 120) and duck (n = 120) carcass samples collected from 12 poultry slaughterhouses between June 2014 and February 2015 in 12 South Korean cities was tested, and 131 samples were positive for Campylobacter. Duck samples showed a higher prevalence (P < 0.05; 93 out of 120) compared to chicken samples (38 out of 120), whereas Campylobacter cell populations from positives were lower (P < 0.05) in ducks (mean count: 183.8 CFU/mL) than in chicken samples (mean count: 499.7 CFU/mL). Most isolates were resistant to nalidixic acid (93.9%), ciprofloxacin (95.4%), tetracycline (72.5%), or enrofloxacin (88.5%), but only a few strains were resistant to chloramphenicol (0.8%) or erythromycin (3.1%). Most of the tested strains were classified into diverse pulsotypes according to repetitive element sequence-based-PCR banding patterns, indicating the diversity of Campylobacter isolates present in chicken and duck samples from poultry slaughterhouses. The emergence of Campylobacter contamination and antibiotic-resistant strains in food animals poses a potential risk to public health and should be regularly monitored for developing proper control measures.

Control of Listeria innocua Biofilms on Food Contact Surfaces with Slightly Acidic Electrolyzed Water and the Risk of Biofilm Cells Transfer to Duck Meat.

Biofilm formation on food contact surfaces is a potential hazard leading to cross-contamination during food processing. We investigated Listeria innocua biofilm formation on various food contact surfaces and compared the washing effect of slightly acidic electrolyzed water (SAEW) at 30, 50, 70, and 120 ppm with that of 200 ppm of sodium hypochlorite (NaClO) on biofilm cells. The risk of L. innocua biofilm transfer and growth on food at retail markets was also investigated. The viability of biofilms that formed on food contact surfaces and then transferred cells to duck meat was confirmed by fluorescence microscopy. L. innocua biofilm formation was greatest on rubber, followed by polypropylene, glass, and stainless steel. Regardless of sanitizer type, washing removed biofilms from polypropylene and stainless steel better than from rubber and glass. Among the various SAEW concentrations, washing with 70 ppm of SAEW for 5 min significantly reduced L. innocua biofilms on food contact surfaces during food processing. Efficiency of transfer of L. innocua biofilm cells was the highest on polypropylene and lowest on stainless steel. The transferred biofilm cells grew to the maximum population density, and the lag time of transferred biofilm cells was longer than that of planktonic cells. The biofilm cells that transferred to duck meat coexisted with live, injured, and dead cells, which indicates that effective washing is essential to remove biofilm on food contact surfaces during food processing to reduce the risk of foodborne disease outbreaks.

Effects of natural antimicrobials with modified atmosphere packaging on the growth kinetics of Listeria monocytogenes in ravioli at various temperatures.

The objective of this study was to investigate the antimicrobial effects of cultured sugar/vinegar (CSV) blend and nisin to control the risk of Listeria monocytogenes in ready to cook (RTC) ravioli. Ravioli dough was prepared with 0.1, 0.3, 0.5, 1% CSV blend and 0.1, 0.2, and 0.3% nisin. Inoculated spinach or artichoke raviolis with 2.0 ± 0.5 log cfu/g of L. monocytogenes were packed aerobically or using modified atmosphere packaging (MAP), and then stored at 4, 10, 17, and 24 °C for 60 days. Growth kinetic parameters of the observed data fit well to the Baranyi equation. Ravioli with spinach filling materials yielded a higher risk than that with artichoke. L. monocytogenes was able to survive in ravioli with artichoke, but did not grow. The addition of 1% CSV blend or 0.3% nisin in spinach ravioli with the combination of MAP effectively controlled the growth of L. monocytogenes at the temperature below 10 °C. The organoleptic quality of spinach ravioli was not also affected by the application of 1% CSV blend. Therefore, the CSV blend can be recommended to improve the microbial safety and quality of natural RTC ravioli at retail market. Practical applications: The risk of ravioli was affected by the filling materials of ravioli at retail market. Addition of 1% cultured sugar/vinegar blend in dough substantially contributes to the extension of shelf-life of MAP spinach raviolis. classification and regression tree analysis results indicate that refrigeration temperature is the main control factor to affect lag time and growth rate, while packaging method is critical for maximum population density.