Y. Benchikh, C. Paris, H. Louaileche, Céline Charbonne, M. Ghoul, L. Chebil, Sift Desk Journals Open Access Journals
In the present study, we investigated the effect of ripening stage on the physicochemical characteristics, phenolic profile, and antioxidant activity of carob (Ceratonia siliqua L.) pulp. Total soluble solids, maturity index, and sugar content of carob pulp increased at the ripe stage, whereas titratable acidity, protein, total phenolic contents, and antioxidant activity decreased. Analysis of phenolic compounds of three carob varieties (Wild, Sisam, and Fleshy) has been carried out by HPLC-DAD-MS. Gallic acid and its derivatives including monogalloylglucoside, digalloyl-glucoside, tetragalloyl-glucoside, and tetragalloylglucoside were the main identified phenolic compounds in the studied carob varieties. Gallotannin contents were higher in the extract of green carob pulp than in the ripe one.
{"title":"Comparative characterization of green and ripe carob (Ceratonia siliqua L.): physicochemical attributes and phenolic profile","authors":"Y. Benchikh, C. Paris, H. Louaileche, Céline Charbonne, M. Ghoul, L. Chebil, Sift Desk Journals Open Access Journals","doi":"10.25177/jfst.1.3.1","DOIUrl":"https://doi.org/10.25177/jfst.1.3.1","url":null,"abstract":"In the present study, we investigated the effect of ripening stage on the physicochemical characteristics, phenolic profile, and antioxidant activity of carob (Ceratonia siliqua L.) pulp. Total soluble solids, maturity index, and sugar content of carob pulp increased at the ripe stage, whereas titratable acidity, protein, total phenolic contents, and antioxidant activity decreased. Analysis of phenolic compounds of three carob varieties (Wild, Sisam, and Fleshy) has been carried out by HPLC-DAD-MS. Gallic acid and its derivatives including monogalloylglucoside, digalloyl-glucoside, tetragalloyl-glucoside, and tetragalloylglucoside were the main identified phenolic compounds in the studied carob varieties. Gallotannin contents were higher in the extract of green carob pulp than in the ripe one.","PeriodicalId":16004,"journal":{"name":"Journal of Food Science and Technology-mysore","volume":"3 1","pages":""},"PeriodicalIF":3.1,"publicationDate":"2016-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88750998","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S. Barbuti, Elena Dalzini, M. Frustoli, Elena Cosciani-Cunico, M. Grisenti, P. Daminelli, Sift Desk Journals Open Access Journals
{"title":"Listeria monocytogenes on cured meat products. A case study on Speck (a typical Italian smoked ham) according to EC Regulation 2073/2005","authors":"S. Barbuti, Elena Dalzini, M. Frustoli, Elena Cosciani-Cunico, M. Grisenti, P. Daminelli, Sift Desk Journals Open Access Journals","doi":"10.25177/jfst.1.3.2","DOIUrl":"https://doi.org/10.25177/jfst.1.3.2","url":null,"abstract":"","PeriodicalId":16004,"journal":{"name":"Journal of Food Science and Technology-mysore","volume":"35 1","pages":""},"PeriodicalIF":3.1,"publicationDate":"2016-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74570590","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The relation between age gelation and proteolytic activity was investigated in this study, as proteolysis is considered to be one of the principal factors that cause gelation. Two different methods for measuring the proteolytic activity of milk samples were applied; the measurement of absorbance at 280 nm and the trinitrobenzene sulfonic acid (TNBS) method. The milk samples used were raw and UHT cow’s and goat’s milk. Proteolysis was also induced in UHT milk by inoculating cells of four different strains of Pseudomonas fluorescens into the milk and the changes taking place were observed. It has been found that the proteolytic activity of raw milk was not affected by a refrigerated storage for 10 days and only after this period it was gradually increased. The higher proteolytic activity of goat’s milk in comparison with cow’s milk during storage and its increased susceptibility to gelation were also established. Furthermore, the importance of storage temperature and the different effect of the four strains of P. fluorescens on proteolytic activity and pH of the UHT milk were shown. Finally, it has been demonstrated that there is a certain level of proteolytic activity in milk that leads to gelation when it is exceeded.
{"title":"Detecting a rapid method for measuring the proteolytic activity of raw and UHT milk.","authors":"I. Sakaridis, M. Lewis","doi":"10.25177/jfst.1.2.4","DOIUrl":"https://doi.org/10.25177/jfst.1.2.4","url":null,"abstract":"The relation between age gelation and proteolytic activity was investigated in this study, as proteolysis is considered to be one of the principal factors that cause gelation. Two different methods for measuring the proteolytic activity of milk samples were applied; the measurement of absorbance at 280 nm and the trinitrobenzene sulfonic acid (TNBS) method. The milk samples used were raw and UHT cow’s and goat’s milk. Proteolysis was also induced in UHT milk by inoculating cells of four different strains of Pseudomonas fluorescens into the milk and the changes taking place were observed. It has been found that the proteolytic activity of raw milk was not affected by a refrigerated storage for 10 days and only after this period it was gradually increased. The higher proteolytic activity of goat’s milk in comparison with cow’s milk during storage and its increased susceptibility to gelation were also established. Furthermore, the importance of storage temperature and the different effect of the four strains of P. fluorescens on proteolytic activity and pH of the UHT milk were shown. Finally, it has been demonstrated that there is a certain level of proteolytic activity in milk that leads to gelation when it is exceeded.","PeriodicalId":16004,"journal":{"name":"Journal of Food Science and Technology-mysore","volume":"104 1","pages":""},"PeriodicalIF":3.1,"publicationDate":"2016-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79195484","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Suman Mishra, J. Monro, K. Armstrong, L. Motoi, K. Sutton, Sift Desk Journals Open Access Journals
Forty six lines of oats from a program of breeding for low glycaemic impact were assessed by in vitro digestive analysis that allowed for theoretical effects of homeostasis on blood glucose concentrations. The oats were steamed and rolled (“rolled oats”; RO), and a portion made into porridge (PO) before in vitro digestive analysis. Carbohydrate digestibility was much greater and more rapid for PO than RO after 20 min digestion (RO, 16.9 g/100 g; PO, 42.5 g/100g on a dry oats basis) but similar after 120 min digestion (43 g versus49.8 g), reflecting a high proportion of slowly digested starch in RO. Taking into account theoretical blood glucose disposal, RO was equivalent in glycaemic effect to 10.8 g of glucose and the PO to 17.5 g of glucose per 40 g serving (10.8 versus 17.5 g glucose equivalents). Based on published GI values, in vitro glycaemic analysis allowing for homeostasis provided realistic relative estimates of effects of processing on glycaemic properties of cereal foods.
通过体外消化分析，对来自低血糖影响育种项目的46个燕麦品系进行了评估，该分析允许体内平衡对血糖浓度的理论影响。燕麦被蒸熟并卷起来(“燕麦卷”);在体外消化分析之前，将一部分做成粥(PO)。消化20 min后，PO的碳水化合物消化率明显高于RO (RO, 16.9 g/100 g;PO, 42.5 g/100g(以干燕麦为基础)，但在消化120分钟后相似(43 g对49.8 g)，反映了RO中缓慢消化的淀粉比例很高。考虑到理论上的血糖处理，RO的降糖作用相当于每40g葡萄糖10.8 g, PO相当于17.5 g葡萄糖(10.8 g vs 17.5 g葡萄糖当量)。基于已发表的GI值，允许体内平衡的体外血糖分析提供了加工对谷物食品血糖特性影响的现实相对估计。
{"title":"Digestive analysis of processing effects on the glycaemic impact of oats in vitro","authors":"Suman Mishra, J. Monro, K. Armstrong, L. Motoi, K. Sutton, Sift Desk Journals Open Access Journals","doi":"10.25177/jfst.1.2.3","DOIUrl":"https://doi.org/10.25177/jfst.1.2.3","url":null,"abstract":"Forty six lines of oats from a program of breeding for low glycaemic impact were assessed by in vitro digestive analysis that allowed for theoretical effects of homeostasis on blood glucose concentrations. The oats were steamed and rolled (“rolled oats”; RO), and a portion made into porridge (PO) before in vitro digestive analysis. Carbohydrate digestibility was much greater and more rapid for PO than RO after 20 min digestion (RO, 16.9 g/100 g; PO, 42.5 g/100g on a dry oats basis) but similar after 120 min digestion (43 g versus49.8 g), reflecting a high proportion of slowly digested starch in RO. Taking into account theoretical blood glucose disposal, RO was equivalent in glycaemic effect to 10.8 g of glucose and the PO to 17.5 g of glucose per 40 g serving (10.8 versus 17.5 g glucose equivalents). Based on published GI values, in vitro glycaemic analysis allowing for homeostasis provided realistic relative estimates of effects of processing on glycaemic properties of cereal foods.","PeriodicalId":16004,"journal":{"name":"Journal of Food Science and Technology-mysore","volume":"1 1","pages":""},"PeriodicalIF":3.1,"publicationDate":"2016-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88737356","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
H. Louaileche, Ouarda Djaoudene, Sift Desk Journals Open Access Journals
The aim of the present study was to assess the effect of storage period and temperature on the nutritional quality of orange jam during storage for 30 days at 25 °C and 35 °C. For that purpose, special attention was paid to total sugars (TS), hydroxymethylfurfural (HMF), free amino acids (FAA), ascorbic acid (AA) and carotenoids. It was observed that storage conditions of jam led to statistically significant alterations for all monitored parameters. The decrease rates at the end of storage under 25 °C and 35 °C, respectively, were 12.5% and 15% for TS, 50% and 59.5% for FAA, 23.5% and 29% for AA and 3% and 19% for carotenoids ; likewise, the increasing were of 144% and 169% for HMF. The practical implications of this work are that the derived knowledge could be very useful to optimize storage conditions in order to improve the quality of this product.
{"title":"Effect of storage time and temperature on the nutritional quality of commercial orange jam.","authors":"H. Louaileche, Ouarda Djaoudene, Sift Desk Journals Open Access Journals","doi":"10.25177/jfst.1.2.5","DOIUrl":"https://doi.org/10.25177/jfst.1.2.5","url":null,"abstract":"The aim of the present study was to assess the effect of storage period and temperature on the nutritional quality of orange jam during storage for 30 days at 25 °C and 35 °C. For that purpose, special attention was paid to total sugars (TS), hydroxymethylfurfural (HMF), free amino acids (FAA), ascorbic acid (AA) and carotenoids. It was observed that storage conditions of jam led to statistically significant alterations for all monitored parameters. The decrease rates at the end of storage under 25 °C and 35 °C, respectively, were 12.5% and 15% for TS, 50% and 59.5% for FAA, 23.5% and 29% for AA and 3% and 19% for carotenoids ; likewise, the increasing were of 144% and 169% for HMF. The practical implications of this work are that the derived knowledge could be very useful to optimize storage conditions in order to improve the quality of this product.","PeriodicalId":16004,"journal":{"name":"Journal of Food Science and Technology-mysore","volume":"13 1","pages":""},"PeriodicalIF":3.1,"publicationDate":"2016-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85220361","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S. Ravishankar, Xeeroy Rada, J. Todd-Searle, M. Friedman, J. Patel, D. Jaroni
Organic fresh produce sales have been increasing in recent years and ensuring safety of produce is important. We investigated the combined antimicrobial effects of plant essential oils and olive extract against Salmonella on organic leafy greens. Organic baby spinach, mature spinach, romaine lettuce, and iceberg lettuce were inoculated with antibiotic-resistant Salmonella Newport and dip-treated in phosphate buffered saline, 3.0% hydrogen peroxide, 0.1% cinnamon leaf oil and 3.0% olive extract or 0.1% oregano oil and 3.0% olive extract combination treatments. Leaves were sampled on days 0, 1, and 3 for enumeration of survivors. Treatment with both antimicrobials induced reductions in Salmonella population of up to 3.5-4 logs, 3-logs and 3-4.4 logs CFU/g on baby spinach, mature spinach and romaine lettuce, respectively. Cinnamon leaf oil and olive extract treatment yielded about 3.0 logs, while oregano oil and olive extract treatment yielded about 3.5 logs CFU/g reduction on iceberg lettuce. Compared to previously reported treatments with individual antimicrobials, the combination treatments had greater antimicrobial effect. The results showed that combination treatments involving essential oils and olive extract are a potential option for use in the wash water for organic leafy greens.
{"title":"Combining essential oils and olive extract for control of multi-drug resistant Salmonella enterica on organic leafy greens","authors":"S. Ravishankar, Xeeroy Rada, J. Todd-Searle, M. Friedman, J. Patel, D. Jaroni","doi":"10.25177/jfst.1.2.2","DOIUrl":"https://doi.org/10.25177/jfst.1.2.2","url":null,"abstract":"Organic fresh produce sales have been increasing in recent years and ensuring safety of produce is important. We investigated the combined antimicrobial effects of plant essential oils and olive extract against Salmonella on organic leafy greens. Organic baby spinach, mature spinach, romaine lettuce, and iceberg lettuce were inoculated with antibiotic-resistant Salmonella Newport and dip-treated in phosphate buffered saline, 3.0% hydrogen peroxide, 0.1% cinnamon leaf oil and 3.0% olive extract or 0.1% oregano oil and 3.0% olive extract combination treatments. Leaves were sampled on days 0, 1, and 3 for enumeration of survivors. Treatment with both antimicrobials induced reductions in Salmonella population of up to 3.5-4 logs, 3-logs and 3-4.4 logs CFU/g on baby spinach, mature spinach and romaine lettuce, respectively. Cinnamon leaf oil and olive extract treatment yielded about 3.0 logs, while oregano oil and olive extract treatment yielded about 3.5 logs CFU/g reduction on iceberg lettuce. Compared to previously reported treatments with individual antimicrobials, the combination treatments had greater antimicrobial effect. The results showed that combination treatments involving essential oils and olive extract are a potential option for use in the wash water for organic leafy greens.","PeriodicalId":16004,"journal":{"name":"Journal of Food Science and Technology-mysore","volume":"50 1","pages":""},"PeriodicalIF":3.1,"publicationDate":"2016-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89814675","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The efficacy of a citric acid-based organic sanitizer (organic Chico WashTM) against Salmonella enterica serovar Newport and background microflora on fresh-cut celery and leeks was investigated. Three concentrations (1:10, 1:20 and 1:40) of Chico Wash were used. For evaluating the efficacy against background microflora, fresh-cut celery or leeks were treated with sanitizers without an initial wash. For evaluating the efficacy against Salmonella, fresh-cut produce samples were initially washed and dip inoculated with 10 7 CFU/ml S. Newport. Samples were immersed in the sanitizer solutions for 2 min. Samples were taken for enumeration of survivors immediately after treatment and after storage at 4oC for 1, 3 and 6 days. Compared to controls washed in water at day 6, Chico Wash reduced Salmonella and background microflora by 0.7-1.5 and 1.2-2.6 log CFU/g, respectively. All three concentrations of Chico Wash showed 0.2- 1.1 log additional reductions in Salmonella population compared to 200 ppm chlorine. At day 6, background microflora population on celery and leeks were 1-1.7 and 1.5-2.2 logs lower, respectively, than that on chlorine treated samples. The results showed that Chico Wash could potentially serve as an alternative for chlorine sanitizer to wash produce.
{"title":"Efficacy of a Citric Acid-based Organic Sanitizer against Salmonella enterica and Background Microflora on Fresh-cut Celery and Leeks.","authors":"S. Ravishankar, Libin Zhu","doi":"10.25177/jfst.1.2.1","DOIUrl":"https://doi.org/10.25177/jfst.1.2.1","url":null,"abstract":"The efficacy of a citric acid-based organic sanitizer (organic Chico WashTM) against Salmonella enterica serovar Newport and background microflora on fresh-cut celery and leeks was investigated. Three concentrations (1:10, 1:20 and 1:40) of Chico Wash were used. For evaluating the efficacy against background microflora, fresh-cut celery or leeks were treated with sanitizers without an initial wash. For evaluating the efficacy against Salmonella, fresh-cut produce samples were initially washed and dip inoculated with 10 7 CFU/ml S. Newport. Samples were immersed in the sanitizer solutions for 2 min. Samples were taken for enumeration of survivors immediately after treatment and after storage at 4oC for 1, 3 and 6 days. Compared to controls washed in water at day 6, Chico Wash reduced Salmonella and background microflora by 0.7-1.5 and 1.2-2.6 log CFU/g, respectively. All three concentrations of Chico Wash showed 0.2- 1.1 log additional reductions in Salmonella population compared to 200 ppm chlorine. At day 6, background microflora population on celery and leeks were 1-1.7 and 1.5-2.2 logs lower, respectively, than that on chlorine treated samples. The results showed that Chico Wash could potentially serve as an alternative for chlorine sanitizer to wash produce.","PeriodicalId":16004,"journal":{"name":"Journal of Food Science and Technology-mysore","volume":"158 1","pages":""},"PeriodicalIF":3.1,"publicationDate":"2016-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86360666","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
V. Dembitsky, D. Levitsky, aPaulina Goldshlag, bVM Dembitsky, Sift Desk Journals Open Access Journals
Pulmonate gastropod mollusks of the genus Helix are being used by human as food more than 10,000 years and they are quite important in the diet of some European countries. Plasmalogens, glyceryl ethers, and diacyl phospholipid forms as well as their fatty aldehydes, alkyl ether glycerides, and fatty acid derivatives were studied. PE of snails, containing aldehydes C16 (variations from 17 to 40%), C18 (11-36%), C9-18:1 (22-31%), C11-20:1 (1-3%), and several minor aldehydes, were detected. The major saturated 1-O-alkyl glycerol ethers were C16:0 and C18:0. Distribution of plasmalogens, alkyl glyceryl ethers, and their fatty aldehydes and fatty alcohols in gastropod species and other mollusks is also discussed.
{"title":"Profiling of bioactive lipids of the wild edible land snails of the genus Helix","authors":"V. Dembitsky, D. Levitsky, aPaulina Goldshlag, bVM Dembitsky, Sift Desk Journals Open Access Journals","doi":"10.25177/jfst.1.1.1","DOIUrl":"https://doi.org/10.25177/jfst.1.1.1","url":null,"abstract":"Pulmonate gastropod mollusks of the genus Helix are being used by human as food more than 10,000 years and they are quite important in the diet of some European countries. Plasmalogens, glyceryl ethers, and diacyl phospholipid forms as well as their fatty aldehydes, alkyl ether glycerides, and fatty acid derivatives were studied. PE of snails, containing aldehydes C16 (variations from 17 to 40%), C18 (11-36%), C9-18:1 (22-31%), C11-20:1 (1-3%), and several minor aldehydes, were detected. The major saturated 1-O-alkyl glycerol ethers were C16:0 and C18:0. Distribution of plasmalogens, alkyl glyceryl ethers, and their fatty aldehydes and fatty alcohols in gastropod species and other mollusks is also discussed.","PeriodicalId":16004,"journal":{"name":"Journal of Food Science and Technology-mysore","volume":"1 1","pages":""},"PeriodicalIF":3.1,"publicationDate":"2016-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82253790","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
B. K. Yoo, Yanhong Liu, V. Juneja, Lihan Huang, C. Hwang, Sift Desk Journals Open Access Journals
The objectives of this study were to examine the effect of stresses on the growth and cytotoxicity of pathogenic Escherichia coli in beef and spinach. A mixture of three strains of Shiga toxin-producing E. coli (STEC) O157:H7 or 4 strains of nonO157 STEC, O26:H11, O103:H1, O104:H4, and O145:NM, was subjected to stress of 2 ppm chlorine, aw 0.97, pH 5, or 15-day starvation. Stressed or non-stressed STEC was inoculated into 5 g of irradiated ground beef or spinach. The cell populations during storage at 8, 12, or 16C for 4 weeks were compared to evaluate the growth variation between O157 and non-O157 STEC. Supernatant from each sample after 24-h incubation at 22C was used to determine Vero-cytotoxicity using [3-(4,5dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, MTS] or lactate dehydrogenase (LDH) assay to evaluate the effects of stresses on the cytotoxicity exhibited by STEC. After one week at 8C, the population of non-stressed non-O157 (3.1 log CFU/g) was significantly (p 0.05) different in beef and spinach. MTS assay showed that stressed O157 and non-O157 STEC exhibited significantly (p<0.05) higher cytotoxicity than the non-stressed controls. The numbers of surviving Vero cells were 47-52% (stressed) vs. 65% (control) in beef and 20-30% (stressed) vs. 52-53% (non-stressed) in spinach. Similarly, LDH assay also indicated an increased cytotoxicity (p<0.05) in stressed O157 and non-O157 STEC than non-stressed controls in spinach. There was no significant difference among the four stresses in inducing the levels of cytotoxicity in O157 or non-O157 STEC. Results showed that STEC cells exposed to sub-lethal stresses might have increased cytotoxicity during subsequent growth in ground beef or spinach. The findings illustrate the importance of applying suitable control measures to eliminate the presence of stressed STEC in beef and spinach processing environment or their subsequent contamination in the products.
{"title":"Effects of Stresses on the Growth and Cytotoxicity of Shiga-Toxin Producing Escherichia coli in Ground Beef and Spinach","authors":"B. K. Yoo, Yanhong Liu, V. Juneja, Lihan Huang, C. Hwang, Sift Desk Journals Open Access Journals","doi":"10.25177/jfst.1.1.5","DOIUrl":"https://doi.org/10.25177/jfst.1.1.5","url":null,"abstract":"The objectives of this study were to examine the effect of stresses on the growth and cytotoxicity of pathogenic Escherichia coli in beef and spinach. A mixture of three strains of Shiga toxin-producing E. coli (STEC) O157:H7 or 4 strains of nonO157 STEC, O26:H11, O103:H1, O104:H4, and O145:NM, was subjected to stress of 2 ppm chlorine, aw 0.97, pH 5, or 15-day starvation. Stressed or non-stressed STEC was inoculated into 5 g of irradiated ground beef or spinach. The cell populations during storage at 8, 12, or 16C for 4 weeks were compared to evaluate the growth variation between O157 and non-O157 STEC. Supernatant from each sample after 24-h incubation at 22C was used to determine Vero-cytotoxicity using [3-(4,5dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, MTS] or lactate dehydrogenase (LDH) assay to evaluate the effects of stresses on the cytotoxicity exhibited by STEC. After one week at 8C, the population of non-stressed non-O157 (3.1 log CFU/g) was significantly (p 0.05) different in beef and spinach. MTS assay showed that stressed O157 and non-O157 STEC exhibited significantly (p<0.05) higher cytotoxicity than the non-stressed controls. The numbers of surviving Vero cells were 47-52% (stressed) vs. 65% (control) in beef and 20-30% (stressed) vs. 52-53% (non-stressed) in spinach. Similarly, LDH assay also indicated an increased cytotoxicity (p<0.05) in stressed O157 and non-O157 STEC than non-stressed controls in spinach. There was no significant difference among the four stresses in inducing the levels of cytotoxicity in O157 or non-O157 STEC. Results showed that STEC cells exposed to sub-lethal stresses might have increased cytotoxicity during subsequent growth in ground beef or spinach. The findings illustrate the importance of applying suitable control measures to eliminate the presence of stressed STEC in beef and spinach processing environment or their subsequent contamination in the products.","PeriodicalId":16004,"journal":{"name":"Journal of Food Science and Technology-mysore","volume":"73 1","pages":""},"PeriodicalIF":3.1,"publicationDate":"2016-01-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87025759","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Vilela, A. Jordão, F. Cosme, Sift Desk Journals Open Access Journals
Each grape variety has its own phenolic profile. However, the concentration of the phenolic compounds present in wine mainly dependson winemaking processes. Phenolic compounds influence wine sensorial characteristics namely taste or mouthfeel, bitterness, astringency and color. Humans can perceive six basic tastes: sweet, salty; sour; umami; fat-taste and bitter taste. This last basic taste is considered as a defense mechanism against the ingestion of potential poisons. Some of the genes,encoding G-protein-coupled receptors TAS2Rs, which translate for these distinct bitter compounds detectors have been identified. Different phenolic compounds activate distinguished combination of TAS2Rs.Astringency in wine is primarily driven by proanthocyanidins, soluble protein-proanthocyanidins complexes which diminish the protective salivary film and bind to the salivary pellicle; insoluble protein-proanthocyanidins complex and proanthocyanidins are rejected against salivary film and trigger astringency sensation via increasing friction. Thus, the aim of this review is to expand the knowledge about the role of wine phenolic compounds in wine sensorial properties, namely in bitterness and astringency phenomenon’s.
{"title":"Wine phenolics: looking for a smooth mouthfeel","authors":"A. Vilela, A. Jordão, F. Cosme, Sift Desk Journals Open Access Journals","doi":"10.25177/jfst.1.1.3","DOIUrl":"https://doi.org/10.25177/jfst.1.1.3","url":null,"abstract":"Each grape variety has its own phenolic profile. However, the concentration of the phenolic compounds present in wine mainly dependson winemaking processes. Phenolic compounds influence wine sensorial characteristics namely taste or mouthfeel, bitterness, astringency and color. Humans can perceive six basic tastes: sweet, salty; sour; umami; fat-taste and bitter taste. This last basic taste is considered as a defense mechanism against the ingestion of potential poisons. Some of the genes,encoding G-protein-coupled receptors TAS2Rs, which translate for these distinct bitter compounds detectors have been identified. Different phenolic compounds activate distinguished combination of TAS2Rs.Astringency in wine is primarily driven by proanthocyanidins, soluble protein-proanthocyanidins complexes which diminish the protective salivary film and bind to the salivary pellicle; insoluble protein-proanthocyanidins complex and proanthocyanidins are rejected against salivary film and trigger astringency sensation via increasing friction. Thus, the aim of this review is to expand the knowledge about the role of wine phenolic compounds in wine sensorial properties, namely in bitterness and astringency phenomenon’s.","PeriodicalId":16004,"journal":{"name":"Journal of Food Science and Technology-mysore","volume":"106 1","pages":""},"PeriodicalIF":3.1,"publicationDate":"2016-01-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73426489","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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