The Experts below are selected from a list of 270 Experts worldwide ranked by ideXlab platform
Petr Kralik - One of the best experts on this subject based on the ideXlab platform.
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Monitoring of selected parasites and other foodborne microorganisms in vegetable products at point of sale
2019Co-Authors: Monika Moravkova, Renata Karpíšková, Petra Vasickova, Pavel Mikel, Michal Slany, Ivana Kolackova, Petr KralikAbstract:Abstract It is supposed that epidemiological data linked to cases of alimentary infection from fresh produce are scarce and usually underestimated. The present study reveals data concerning the occurrence of less studied foodborne pathogens such as parasites ( Giardia intestinalis , Cryptosporidium parvum/hominis ) and viruses (norovirus, hepatitis A virus) in 175 samples of fresh-cut Vegetables, Frozen Vegetables and sprouts. In addition, samples were also analyzed for the presence of bacterial indicators of production hygiene such as Escherichia coli and Staphylococcus aureus . Our results revealed that DNA of G. intestinalis was found in two samples (1.1%) of mixed fresh vegetable salads and mixed Frozen Vegetables at a level of 100 CFU/g. Norovirus was detected in two samples (1.1%) of rucola and Frozen mixed Vegetables. No sample was positive for C. parvum/hominis or hepatitis A virus. Our results highlight the need for microbial analysis of food of non-animal origin for specific parasitic and viral agents not generally monitored in these food category types, but their presence poses risks for alimentary infection.
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occurrence of cronobacter spp in ready to eat vegetable products Frozen Vegetables and sprouts examined using cultivation and real time pcr methods
Journal of Food Science, 2018Co-Authors: M. Moravkova, Veronika Verbikova, Veronika Huvarová, Vladimir Babak, Hana Cahlikova, Renata Karpíšková, Petr KralikAbstract:Environmental matrices and food products are hypothesized to be sources of Cronobacter spp. The severity of neonatal infections, increasing number of cases in elderly and immunocompromised individuals, as well as isolation of Cronobacter spp. from clinical materials demands that more attention should be paid to Cronobacter spp. detection and occurrence of the bacteria in food products. Here, a total of 175 samples of ready-to-eat Vegetables, Frozen Vegetables, and sprouted seeds were collected during a period of 1 year and examined for the presence of Cronobacter spp. using a cultivation method with two different sample preparations and real-time polymerase chain reaction (qPCR). In total, Cronobacter spp. were detected in 22.3% of tested samples using cultivation. In comparison, direct qPCR detected Cronobacter spp. in 37.7% of these samples (p < 0.01; Fisher's exact test) and the numbers of genome equivalents per gram reached 108 in some samples of sprouts. Cronobacter spp. were isolated from 51.4%, 37.2%, and 5.2% samples of sprouts, Frozen Vegetables, and cut green leaves/salads, respectively. Using qPCR, the most frequently contaminated sample types were sprouts (91.4%) and Frozen Vegetables (60.5%), whereas the rate of positivity for cut green leaves/salads was, in comparison, only 8.2% (p < 0.01; χ2 -test for independence). PRACTICAL APPLICATION: This study provided valuable information on the occurrence of Cronobacter spp. in ready-to-eat Vegetables using cultivation and qPCR. Cronobacter spp. are emerging opportunistic pathogens that can be present in food of plant origin. Cronobacter spp. were isolated from sprouts, Frozen Vegetables, and cut green leaves/salads, and the numbers of genome equivalents per gram reached 108 in some samples of sprouts.; © 2018 Institute of Food Technologists®.
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Occurrence of Cronobacter Spp. in Ready‐to‐Eat Vegetable Products, Frozen Vegetables, and Sprouts Examined Using Cultivation and Real‐Time PCR Methods
Journal of food science, 2018Co-Authors: M. Moravkova, Veronika Verbikova, Veronika Huvarová, Vladimir Babak, Hana Cahlikova, Renata Karpíšková, Petr KralikAbstract:Environmental matrices and food products are hypothesized to be sources of Cronobacter spp. The severity of neonatal infections, increasing number of cases in elderly and immunocompromised individuals, as well as isolation of Cronobacter spp. from clinical materials demands that more attention should be paid to Cronobacter spp. detection and occurrence of the bacteria in food products. Here, a total of 175 samples of ready-to-eat Vegetables, Frozen Vegetables, and sprouted seeds were collected during a period of 1 year and examined for the presence of Cronobacter spp. using a cultivation method with two different sample preparations and real-time polymerase chain reaction (qPCR). In total, Cronobacter spp. were detected in 22.3% of tested samples using cultivation. In comparison, direct qPCR detected Cronobacter spp. in 37.7% of these samples (p < 0.01; Fisher's exact test) and the numbers of genome equivalents per gram reached 108 in some samples of sprouts. Cronobacter spp. were isolated from 51.4%, 37.2%, and 5.2% samples of sprouts, Frozen Vegetables, and cut green leaves/salads, respectively. Using qPCR, the most frequently contaminated sample types were sprouts (91.4%) and Frozen Vegetables (60.5%), whereas the rate of positivity for cut green leaves/salads was, in comparison, only 8.2% (p < 0.01; χ2 -test for independence). PRACTICAL APPLICATION: This study provided valuable information on the occurrence of Cronobacter spp. in ready-to-eat Vegetables using cultivation and qPCR. Cronobacter spp. are emerging opportunistic pathogens that can be present in food of plant origin. Cronobacter spp. were isolated from sprouts, Frozen Vegetables, and cut green leaves/salads, and the numbers of genome equivalents per gram reached 108 in some samples of sprouts.; © 2018 Institute of Food Technologists®.
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detection and quantification of listeria monocytogenes in ready to eat Vegetables Frozen Vegetables and sprouts examined by culture methods and real time pcr
Journal of Food and Nutrition Research, 2017Co-Authors: Monika Moravkova, Veronika Verbikova, Vladimir Babak, Hana Cahlikova, Renata Karpíšková, Veronika Michna, Petr KralikAbstract:In this study, a total of 175 samples of ready-to-eat Vegetables, Frozen Vegetables and sprouted seeds originating in 10 states of the European Union and from 32 manufacturers were collected during a period of one year and examined for the presence of Listeria monocytogenes using standard culture methods and qPCR. In addition to these methods, isolation of Listeria monocytogenes was also carried out following a unified sample preparation for combined downstream use in culture and qPCR analysis. Standard culture and culture preceded by unified sample preparation, showed that L. monocytogenes was present in 6.9% and 11.4% of analyzed samples, respectively, in low numbers. Application of qPCR revealed only 2.3% of samples to be positive for L. monocytogenes in small quantities (less than 10 cells/gram). A statistically significant higher occurrence of L. monocytogenes was seen in Frozen Vegetables compared to ready to eat Vegetables (p<0.01; Fisher’s exact post-hoc tests with Bonferroni’s correction) or sprouts (p<0.05; Fisher’s exact post-hoc tests with Bonferroni’s correction). Therefore, temperature abuse in food containing pieces of Frozen Vegetables without any processing such as cooking, may pose health risks, especially for sensitive individuals such as pregnant women, children, the elderly, and immunocompromised individuals.
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Detection and Quantification of Listeria monocytogenes in Ready-to-eat Vegetables, Frozen Vegetables and Sprouts Examined by Culture Methods and Real-time PCR
Journal of Food and Nutrition Research, 2017Co-Authors: Monika Moravkova, Veronika Verbikova, Vladimir Babak, Hana Cahlikova, Renata Karpíšková, Veronika Michna, Petr KralikAbstract:In this study, a total of 175 samples of ready-to-eat Vegetables, Frozen Vegetables and sprouted seeds originating in 10 states of the European Union and from 32 manufacturers were collected during a period of one year and examined for the presence of Listeria monocytogenes using standard culture methods and qPCR. In addition to these methods, isolation of Listeria monocytogenes was also carried out following a unified sample preparation for combined downstream use in culture and qPCR analysis. Standard culture and culture preceded by unified sample preparation, showed that L. monocytogenes was present in 6.9% and 11.4% of analyzed samples, respectively, in low numbers. Application of qPCR revealed only 2.3% of samples to be positive for L. monocytogenes in small quantities (less than 10 cells/gram). A statistically significant higher occurrence of L. monocytogenes was seen in Frozen Vegetables compared to ready to eat Vegetables (p
Eva Almenar - One of the best experts on this subject based on the ideXlab platform.
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Effect of microwave steamable bag design on the preservation of ascorbic acid and antioxidant capacity and on the physical properties of cooked Frozen Vegetables: A case study on broccoli (Brassica oleracea)
LWT - Food Science and Technology, 2017Co-Authors: Xueying Zhong, Kirk D. Dolan, Muhammad Siddiq, Dalbir Singh Sogi, Bruce Harte, Eva AlmenarAbstract:Abstract Published data on new cooking methods such as steamable bag microwaving is minimal. This study investigated the effect of steamable bag design, including shape and surface area, on the changes in ascorbic acid, antioxidant capacity, and physical quality of Frozen broccoli during microwaving. The results showed that most of the studied parameters were more affected by the shape of steamable bags than by surface area. Broccoli cooked in more square-shaped steamable bags retained significantly higher vitamin C content, was less green and more yellow, and firmer than broccoli cooked in more rectangular-shaped steamable bags. The smaller the surface area, the softer the broccoli became after cooking; however, vitamin C content and color did not follow this trend. Neither the shape nor surface area of steamable bags had an effect on lightness and antioxidant content. These results demonstrated the importance of controlling the surface area and shape of steamable bags to optimize Frozen Vegetables’ qualities.
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Effect of steamable bag microwaving versus traditional cooking methods on nutritional preservation and physical properties of Frozen Vegetables: A case study on broccoli (Brassica oleracea)
Innovative Food Science & Emerging Technologies, 2015Co-Authors: Xueying Zhong, Kirk D. Dolan, Eva AlmenarAbstract:Abstract The effect of steamable bag microwaving on the nutritional value and physical properties of Frozen Vegetables was studied and compared to that of traditional cooking methods (i.e., steamer steaming and traditional microwaving) for the first time. Broccoli was chosen for this study since it is one of the most consumed Frozen Vegetables. Titration, oxygen radical absorbance capacity assay, colorimetry (L*, a*, b*, hue angle, and total color difference) and texturometry were used for evaluation. The results show that steamable bag microwaving performs better than traditional microwaving and is equal to steamer steaming in retaining ascorbic acid content and increasing antioxidant activity compared to thawed Frozen broccoli. Steamable bag microwaving tenderizes Frozen broccoli faster, and better maintains the broccoli lightness and yellowness than steamer steaming and traditional microwaving. These findings show that steamable bag microwaving is a more appropriate cooking method for Frozen broccoli than traditional cooking methods. Industrial relevance Steamable bag microwaving is an emerging cooking technology for Frozen Vegetables. While steamable bag microwaving provides consumers with convenience and safety compared to other cooking technologies (i.e., traditional microwaving, steaming, and boiling), there is no information on the effect of steamable bag microwaving on nutritional and physical changes of Frozen Vegetables. Our findings show that steamable bag microwaving is more appropriate than traditional cooking methods and satisfies current consumers' needs better (i.e., high nutritional content, fresh-like produce, and time savings).
Nicoletta Pellegrini - One of the best experts on this subject based on the ideXlab platform.
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Effect of two cooking procedures on phytochemical compounds, total antioxidant capacity and colour of selected Frozen Vegetables
Food Chemistry, 2011Co-Authors: Teresa Mazzeo, Denis N’dri, Emma Chiavaro, Attilio Visconti, Vincenzo Fogliano, Nicoletta PellegriniAbstract:Abstract The effect of boiling and steaming on content of phytochemicals (carotenoids, chlorophylls, polyphenols and ascorbic acid) all evaluated by HPLC, total antioxidant capacity (TAC) measured by means of TEAC and FRAP assays and colour ( L ∗ , a ∗ , b ∗ , C, H°) of three Frozen Vegetables (carrot, cauliflower and spinach) was evaluated. Steaming increased the content of polyphenols in all Vegetables and limited the depletion of carotenoids in spinach. Accordingly, TAC remained unvaried or increased both for steamed carrot and spinach. Boiling had a more marked effect on nutritional pattern of Frozen Vegetables in comparison with steaming, leading to a general loss of phytochemical compounds and TAC for all Vegetables. Ascorbic acid was detected only in cauliflower and decreased after both treatments. Colour of Frozen Vegetables was only slightly influenced by cooking, probably due to blanching pre-treatment. Slight decrements of redness ( a ∗ ) for carrot in relation with loss of carotenoids and greenness (− a ∗ ) for steamed spinach, due to a significant loss of total chlorophylls, were observed. Steaming increased TAC and bioaccessibility of polyphenols in all Frozen Vegetables while boiling led to a general loss of carotenoids and phenolic compounds and a TAC decrease.
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effect of different cooking methods on color phytochemical concentration and antioxidant capacity of raw and Frozen brassica Vegetables
Journal of Agricultural and Food Chemistry, 2010Co-Authors: Nicoletta Pellegrini, Teresa Mazzeo, Emma Chiavaro, Vincenzo Fogliano, Claudio Gardana, Daniele Contino, Monica Gallo, Patrizia Riso, Marisa PorriniAbstract:This study evaluated the effect of common cooking practices (i.e., boiling, microwaving, and basket and oven steaming) on the phytochemical content (carotenoids, chlorophylls, glucosinolates, polyphenols, and ascorbic acid), total antioxidant capacity (TAC), and color changes of three generally consumed Brassica Vegetables analyzed fresh and Frozen. Among cooking procedures, boiling determined an increase of fresh broccoli carotenoids and fresh Brussels sprout polyphenols, whereas a decrease of almost all other phytochemicals in fresh and Frozen samples was observed. Steaming procedures determined a release of polyphenols in both fresh and Frozen samples. Microwaving was the best cooking method for maintaining the color of both fresh and Frozen Vegetables and obtaining a good retention of glucosinolates. During all cooking procedures, ascorbic acid was lost in great amount from all Vegetables. Chlorophylls were more stable in Frozen samples than in fresh ones, even though steaming methods were able to bet...
M. Moravkova - One of the best experts on this subject based on the ideXlab platform.
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occurrence of cronobacter spp in ready to eat vegetable products Frozen Vegetables and sprouts examined using cultivation and real time pcr methods
Journal of Food Science, 2018Co-Authors: M. Moravkova, Veronika Verbikova, Veronika Huvarová, Vladimir Babak, Hana Cahlikova, Renata Karpíšková, Petr KralikAbstract:Environmental matrices and food products are hypothesized to be sources of Cronobacter spp. The severity of neonatal infections, increasing number of cases in elderly and immunocompromised individuals, as well as isolation of Cronobacter spp. from clinical materials demands that more attention should be paid to Cronobacter spp. detection and occurrence of the bacteria in food products. Here, a total of 175 samples of ready-to-eat Vegetables, Frozen Vegetables, and sprouted seeds were collected during a period of 1 year and examined for the presence of Cronobacter spp. using a cultivation method with two different sample preparations and real-time polymerase chain reaction (qPCR). In total, Cronobacter spp. were detected in 22.3% of tested samples using cultivation. In comparison, direct qPCR detected Cronobacter spp. in 37.7% of these samples (p < 0.01; Fisher's exact test) and the numbers of genome equivalents per gram reached 108 in some samples of sprouts. Cronobacter spp. were isolated from 51.4%, 37.2%, and 5.2% samples of sprouts, Frozen Vegetables, and cut green leaves/salads, respectively. Using qPCR, the most frequently contaminated sample types were sprouts (91.4%) and Frozen Vegetables (60.5%), whereas the rate of positivity for cut green leaves/salads was, in comparison, only 8.2% (p < 0.01; χ2 -test for independence). PRACTICAL APPLICATION: This study provided valuable information on the occurrence of Cronobacter spp. in ready-to-eat Vegetables using cultivation and qPCR. Cronobacter spp. are emerging opportunistic pathogens that can be present in food of plant origin. Cronobacter spp. were isolated from sprouts, Frozen Vegetables, and cut green leaves/salads, and the numbers of genome equivalents per gram reached 108 in some samples of sprouts.; © 2018 Institute of Food Technologists®.
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Occurrence of Cronobacter Spp. in Ready‐to‐Eat Vegetable Products, Frozen Vegetables, and Sprouts Examined Using Cultivation and Real‐Time PCR Methods
Journal of food science, 2018Co-Authors: M. Moravkova, Veronika Verbikova, Veronika Huvarová, Vladimir Babak, Hana Cahlikova, Renata Karpíšková, Petr KralikAbstract:Environmental matrices and food products are hypothesized to be sources of Cronobacter spp. The severity of neonatal infections, increasing number of cases in elderly and immunocompromised individuals, as well as isolation of Cronobacter spp. from clinical materials demands that more attention should be paid to Cronobacter spp. detection and occurrence of the bacteria in food products. Here, a total of 175 samples of ready-to-eat Vegetables, Frozen Vegetables, and sprouted seeds were collected during a period of 1 year and examined for the presence of Cronobacter spp. using a cultivation method with two different sample preparations and real-time polymerase chain reaction (qPCR). In total, Cronobacter spp. were detected in 22.3% of tested samples using cultivation. In comparison, direct qPCR detected Cronobacter spp. in 37.7% of these samples (p < 0.01; Fisher's exact test) and the numbers of genome equivalents per gram reached 108 in some samples of sprouts. Cronobacter spp. were isolated from 51.4%, 37.2%, and 5.2% samples of sprouts, Frozen Vegetables, and cut green leaves/salads, respectively. Using qPCR, the most frequently contaminated sample types were sprouts (91.4%) and Frozen Vegetables (60.5%), whereas the rate of positivity for cut green leaves/salads was, in comparison, only 8.2% (p < 0.01; χ2 -test for independence). PRACTICAL APPLICATION: This study provided valuable information on the occurrence of Cronobacter spp. in ready-to-eat Vegetables using cultivation and qPCR. Cronobacter spp. are emerging opportunistic pathogens that can be present in food of plant origin. Cronobacter spp. were isolated from sprouts, Frozen Vegetables, and cut green leaves/salads, and the numbers of genome equivalents per gram reached 108 in some samples of sprouts.; © 2018 Institute of Food Technologists®.
Yasmine Probst - One of the best experts on this subject based on the ideXlab platform.
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Translating advice to eat more Vegetables into practice: observations from a 12-month weight loss trial
European journal of clinical nutrition, 2018Co-Authors: Jane E O'shea, Linda C Tapsell, Rebecca L Thorne, Yasmine ProbstAbstract:This study aimed to identify the main vegetable sources of overweight participants during a 12-month randomised controlled trial for weight loss. Secondary analysis using data from diet history interviews to determine changes to daily vegetable intake amounts and types throughout the trial at 0, 3 and 12 months. Pre-trial 77% participants consumed Frozen Vegetables. At baseline (n = 113, 85 F), participants reported 345 ± 170 (56–920) g/day Vegetables increasing to 498 ± 180 (146–930) g/day at 3 months and remaining stable at 475 ± 169(170–1053) g/day by 12 months (p = 0.001). At baseline, 32 of 34 different vegetable categories were reported, mainly tomato (69.9 g/day) and, potato (58.2 g/day). After 3 months (n = 109), seven Vegetables remained in the top 10 reported (contributing 72%). Tomato remained top ranked to 12 months. Following advice to consume more Vegetables, consumption increased above the Australian Dietary recommendation of ~375 g/day. Tomatoes remained a mainstay regardless of the time of year, but choices changed with time. Frozen Vegetables may be a feasible option.
