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Microbiological Quality (microbiological + quality)
Selected AbstractsINFLUENCE OF FROZEN PERIOD ON THE PROXIMATE COMPOSITION AND MICROBIOLOGICAL QUALITY OF NILE TILAPIA FISH (OREOCHROMIS NILOTICUS)JOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 4 2010SHIMELIS A. EMIRE ABSTRACT The rationale of the study was to investigate the influence of frozen period on quality of fish fillet. The proximate composition and microbiological analyses were carried out at 15 days interval on tilapia fish fillets during frozen storage. It was found that the protein, moisture and ash contents decreased significantly (P < 0.05) during the entire storage period. However, the fat content increased from 0.37 ± 0.01 to 0.56 ± 0.01 g/100 g of fillet. The total volatile bases nitrogen and pH values also increased significantly The total bacterial load in fresh fillets was reduced from 2.57 × 106 to 8.2 × 105 cfu/g after 90 days of frozen storage. The total coliforms decreased from 460 to 23 MPN/g and the fecal coliforms decreased from 23 MPN/g to undetectable level, respectively. Thus, a significant quality loss was observed for tilapia during storage. However, the present frozen conditions retained the fish material under acceptable microbiological conditions for human consumption. PRACTICAL APPLICATIONS The main challenge that fish industries face in developing countries like Ethiopia is to comply with consumer expectations, particularly on product quality. The quality of fresh fish is one of the key factors that govern the shelf life of the final product at low temperature preservation. The Ethiopian fish production and marketing enterprise is vested with the responsibility of inland fisheries processing and marketing. The enterprise, without any scientific basis, labeled the frozen tilapia fish shelf life to be 9 months. Therefore, the aim of this study was to investigate the low-temperature (,18C) preservation technique practiced by the enterprise in order to evaluate the influence of frozen period on quality of a fish fillet. The results on changes in proximate composition and microbial load of Nile tilapia fish fillet enabled to determine the frozen period of a fish fillet that can be fit for human consumption devoid of deterioration. The results can also be used for further investigation and detailed research is required to help commercial processors beyond 90 days of frozen storage. [source] AQUEOUS GARLIC EXTRACT AND MICROBIOLOGICAL QUALITY OF REFRIGERATED POULTRY MEATJOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 2 2005KEILY ALVES DE MOURA OLIVEIRA ABSTRACT The antibacterial effect of garlic extract (5, 10 and 15%) was investigated on poultry carcasses obtained from a slaughterhouse, stored under refrigeration, and evaluated at selected time intervals. The effect of the garlic extract on the microbial contaminants of the poultry carcass surface , Salmonella, strict and facultative aerobic, mesophilic, and total and fecal coliforms , was evaluated. The garlic extract exhibited a concentration-dependent reduction of microbial contamination. Garlic extract concentrations of 10 and 15% were the most effective. The bacteriostatic action of garlic extract against mesophilic microbiota can be observed until the third storage day. The count of total and fecal coliforms remained low during the storage period. Chicken feed was the apparent source of Salmonella contamination, and the aqueous garlic extract was not effective against Salmonella. [source] Effectiveness of Radiation Processing for Elimination of Salmonella Typhimurium from Minimally Processed Pineapple (Ananas comosus Merr.)JOURNAL OF FOOD SCIENCE, Issue 3 2007Ravindranath Shashidhar ABSTRACT:, The microbiological quality of market samples of minimally processed (MP) pineapple was examined. The effectiveness of radiation treatment in eliminating Salmonella Typhimurium from laboratory inoculated ready-to-eat pineapple slices was also studied. Microbiological quality of minimally processed pineapple samples from Mumbai market was poor; 8.8% of the samples were positive for Salmonella. D10 (the radiation dose required to reduce bacterial population by 90%) value for S. Typhimurium inoculated in pineapple was 0.242 kGy. Inoculated pack studies in minimally processed pineapple showed that the treatment with a 2-kGy dose of gamma radiation could eliminate 5 log CFU/g of S. Typhimurium. The pathogen was not detected from radiation-processed samples up to 12 d during storage at 4 and 10 °C. The processing of market samples with 1 and 2 kGy was effective in improving the microbiological quality of these products. [source] The effects of starter culture on chemical composition, microbiological and sensory characteristics of Turkish Ka,ar Cheese during ripeningINTERNATIONAL JOURNAL OF DAIRY TECHNOLOGY, Issue 4 2007DURMU Ka,ar cheese samples were produced from raw milk and starter culture-added pasteurized milk. Chemical, microbiological and organoleptic properties of ka,ar cheeses were analysed at certain times during the ripening periods (on the 1st, 7th, 15th, 30th, 60th, 90th days). Generally, chemical parameters were not affected by starter culture. The pH, ripening index, water-soluble nitrogen and non-protein nitrogen did not show significant differences between the cheese samples. The addition of starter affected the microbiological quality of the cheeses. Starter culture-added ka,ar cheeses contained low levels of total aerobic mesophilic bacteria, moulds and yeasts, and coliforms, and achieved higher organoleptic scores than those of cheeses made from raw milk. The starter cultures contributed to acidity and microbial quality of the cheese. [source] Shelf life extension of durum semolina-based fresh pastaINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 8 2010Cristina Costa Summary In this work, the combined effects of chitosan, modified atmosphere packaging (MAP) and packaging barrier properties on shelf life of fresh pasta is presented. In particular, all pasta samples were packaged under active and passive MAP in two different polymeric films with high and low barrier properties. In order to assess the influence of the variables described beforehand on the shelf life of pasta, the sensorial and microbiological quality has been monitored during storage. Results confirmed the antimicrobial properties of chitosan. Moreover, the findings recorded in this study suggest that the shelf life of fresh pasta is limited by the sensorial characteristics. Statistically significant differences between the shelf life of pasta packaged in low barrier and high barrier films were found. The best result was obtained for samples packaged in high barrier film, due to the ability of the packaging to maintain the gas headspace conditions during the storage. [source] Effects of drying process on biochemical and microbiological quality of silverside (fish) Atherina lagunaeINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 6 2010Salah Selmi Summary Changes in biochemical and microbiological quality of silverside during two drying process were investigated. Total fatty acid and amino acid contents in silverside were 5.42 and 10.9 g 100 g,1 fresh sample, respectively, in which, palmitic acid and glutamic acid were the most abundant. N-3 and n-6 polyunsaturated fatty acids (PUFA) levels were 0.59 and 0.62 g 100 g,1 fresh silverside respectively. After hot air and solar drying treatments, Peroxide value and thiobarbituric acid reactive substances of the total lipids increased significantly (P < 0.05) to reach 2.58 and 3.41 meq active O2 kg,1 oil and 0.87 and 1.27 mg MA kg,1 oil, respectively. Fatty acid profile of non-polar lipid remains unchanged during experimental drying process. However, PUFA (% of total fatty acids) of polar lipid decreased significantly (P < 0.05) during both drying process with lower levels in solar drying process. Drying conditions had a significant effect on the microbiological quality. Therefore, mesophiles and total coliforms increased within drying treatment with higher counts in solar drying process. [source] Effect of washing with citric acid and antioxidants on the colour and microbiological quality of whole mushrooms (Agaricus bisporus L.)INTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 12 2009Ana Simón Summary The effect of washing with citric acid followed by anti-browning treatment involving rinsing with sodium d -isoascorbate or sodium l -ascorbate on the colour, microbiological quality and bacterial blotch of whole mushrooms when stored at 5 °C for up to 13 days at 80% RH was evaluated. Washing with 1% citric acid reduced Pseudomonas counts avoiding bacterial blotch, but caused an important deterioration of colour. When washing with citric acid was followed by an anti-browning treatment, mushrooms colour was improved, at the same time as bacterial blotch was reduced, although the decrease of Pseudomonas counts was smaller than in mushrooms washed only with citric acid. The most effective treatment was washing with 1% citric acid followed by anti-browning treatment with 1.5% sodium l -ascorbate. [source] The effects of soluble gas stabilisation on the quality of packed sardine fillets (Sardina pilchardus) stored in air, VP and MAPINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 11 2008Rogério Mendes Summary Sardine (Sardina pilchardus) is a species that for its abundance assumes great importance in the Portuguese fishing sector. In order to contribute for a better utilisation of this species, the aim of this study was to investigate the effect of the pre-treatment with soluble gas stabilisation (SGS) (100% CO2 at 2 bar, during 15 and 30 min) on the quality and shelf-life of sardine fillets, packed in air (AP), vacuum (VP) and modified atmosphere (MAP: 5% O2/35% CO2/60% N2). During the chilled storage, the quality changes were evaluated by sensory evaluation, chemical and microbiological analysis. The total volatile basic nitrogen content remained almost constant, between 16 and 19 mg N/100 g muscle, during the storage period, for all samples. The TBARs values increased with storage time, for all batches and storage conditions. The application of SGS treatment to sardine fillets, resulted in a bacteriostatic effect, contributing to the improvement of the microbiological quality of fillets. Considering a sensory criteria, the shelf-life of SGS pre-treated sardine fillets was found to be 5 days in AP and MAP while in VP-treated fillets a shelf-life of 8 days was reported. At sensory rejection, sardine fillets presented a K -value of 30% in AP and MAP batches and 40% in VP batch. [source] Chemical and microbiological quality of Garris, Sudanese fermented camel's milk productINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 3 2006Abdel Moneim El-Hadi Sulieman Summary In the present study, some of the chemical and microbiological characteristics of garris, a Sudanese traditionally fermented camel's milk product, were investigated. The chemical analyses included, pH, titrable acidity and ethanol contents. A total of 100 strains of lactic acid bacteria (LAB) were isolated from twenty samples of traditionally fermented household garris. The selected isolates were phenotypically characterized by their ability to ferment 49 carbohydrates using API 50 CHL kits and additional biochemical tests. LAB dominated the microflora of garris samples, and the major genera were Lactobacillus (74%), followed by Lactococcus (12%), Enterococcus (10%) and Leuconostocs (4%). The most predominant Lactobacillus species were identified as Lactobacillus paracasei ssp. paracasei (64 strains), L. fermentum (seven strains) and only three strains as L. plantarum. Most strains produced the enzymes that are relevant to cultured dairy product processing. The Lactococcus species were identified as Lactococcus lactis. The average pH value of the samples was 4.42 ± 0.21. The pH values were accompanied with increasing of titrable acidity which averaged 1.72 ± 0.04%. The relatively high amounts of ethanol detected in all samples (average 1.40 ± 0.03%) together with the high yeasts counts (6.0 ± 0.53 log10 cfu mL,1), indicated that the fermentation process of garris is a yeast-lactic fermentation. [source] Decontamination of deboned chicken legs by vacuum-tumbling in lactic acid solutionINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 1 2006François Deumier Summary Vacuum tumbling in a 1,5% lactic acid solution for a short time (1,10 min) improves the microbiological quality of deboned chicken legs, while inducing a light acidification and water absorption. The most significant variable of the process is the tumbling speed. High tumbling speeds lead to a high decontamination level of the chicken legs with regard to total viable counts and Enterobacteriaceae. Sodium lactate alone is unable to induce any decontamination at the same concentrations. Decontamination is probably more linked to acidification than to lactate ions. The use of vacuum tumbled (1 min in a 1% lactic acid solution) deboned chicken legs in the industrial manufacture of fresh chicken sausages led to a clear decrease in the number of Salmonella -positive batches. The incidence of positive batches was reduced threefold and the acid decontamination process did not adversely affect the sensory quality of the sausages. [source] Microbiological analysis of composts produced on South Carolina poultry farmsJOURNAL OF APPLIED MICROBIOLOGY, Issue 6 2010M.W. Shepherd Jr Abstract Aims:, The purpose of this study was to determine whether the methods used in compost operations of small and medium-sized poultry forms resulted in the production of an amendment free of foodborne pathogens. Methods and Results:, Nine compost heaps on five South Carolina poultry farms were surveyed at different stages of the composting process. Compost samples were analysed for coliforms and enriched for Escherichia coli O157:H7, Salmonella spp. and Listeria monocytogenes. The waste materials and composting practices differed among the surveyed farms. On two farms, new materials were added to heaps that had previously completed the active composting phase. Five compost heaps did not reach an internal temperature of 55°C, and c. 62% of all internal samples in the first composting phase contained moisture contents <40%. Escherichia coli was detected in 63% of the surface samples (n = 38) and 9·8% of the internal samples (n = 82) from the first composting phase, as compared with 16·7% of the surface samples (n = 12) and 0% internal samples (n = 24) from the second composting phase. Salmonella was detected in 26 and 6·1% of all surface and internal samples collected from heaps in the first composting phase, respectively, but was absent in all compost samples undergoing a second composting phase. The predominant Salmonella serotypes were Thompson, Montevideo and Anatum. Neither E. coli O157:H7 nor L. monocytogenes was detected in any of the samples. Conclusions:, Our results indicate that the conditions at the compost surface are suitable for pathogen survival, and the complete composting process can result in the elimination of pathogens in poultry wastes. Significance and Impact of the Study:, This research provides information regarding the effectiveness of the composting practices and microbiological quality of poultry compost produced by small- and medium-sized farms. Ensuring the safety of compost that may be applied to soils should be an integral part of preharvest food safety programme. [source] Occurrence of bacterial indicators and bacteriophages infecting enteric bacteria in groundwater in different geographical areasJOURNAL OF APPLIED MICROBIOLOGY, Issue 1 2006F. Lucena Abstract Aims:, The aim of this research was to determine the suitability of coliphages (bacteriophages) for assessing the microbial quality of groundwater. Methods and Results:, The number of several bacterial indicators (faecal coliforms, Escherichia coli, enterococci and spores of sulfite-reducing clostridia) and bacteriophages (somatic coliphages, F-specific RNA bacteriophages and bacteriophages infecting Bacteroides fragilis) were determined in groundwater of aquifers in various geographical areas. Results show that the relative abundance, determined as percentages of positive detections, of the bacterial indicators and bacteriophages varies depending on the aquifer. Conclusions:, A single bacterial indicator may not be enough to assess microbiological quality in certain aquifers. One bacterial indicator and a bacteriophage parameter provide more information than two bacterial indicators. Significance and Impact of the Study:, Coliphages (CPH) provide different information from that provided by bacterial indicators on the microbial quality of groundwater in different geographical areas. Easy, fast and inexpensive methods for the detection of CPH are feasible in both industrialized and developing countries. [source] Microbial interaction in cooked cured meat products under vacuum or modified atmosphere at 4°CJOURNAL OF APPLIED MICROBIOLOGY, Issue 3 2002J. Metaxopoulos Aims: To investigate the antagonistic activity of two lactic acid strains against the spoilage microflora in cooked cured meat products, vacuum or modified atmosphere packed at 4°C and to determine the inhibitory capacity of their bacteriocins. Methods and Results: Frankfurter-type sausages and sliced cooked cured pork shoulder were inoculated with Leuconostoc mesenteroides L124 and Lactobacillus curvatus L442 or with their bacteriocins. The microbial, physico-chemical (pH, l - and d -lactate, acetate and ammonia) and colour changes were studied. Results under vacuum packaging showed that in the uninoculated samples of the pork product the spoilage microflora grew but in the inoculated ones the spoilage microorganisms (e.g. Brochothrix thermosphacta and enterococci) reduced during the storage. This observation was more pronounced in the samples with the addition of bacteriocins. In the frankfurter-type sausages the spoilage microflora did not grow in the uninoculated and inoculated samples. In the modified atmosphere enriched in CO2 the population of spoilage microflora remained at low levels in both products, indicating that CO2 has an effect on thespoilage microorganisms' growth. In the pork product the concentrations of acetate and d -lactate increased while l -lactate decreased, but in the frankfurter-type sausages increase of acetate and d -lactate was not observed. Conclusions: Lactic acid strains had an effect on the spoilage microflora growth but did not affect, negatively, the organoleptic properties of the products. These strains may be used as biopreservative cultures or their bacteriocins could be an important contribution to microbiological quality of meat products. Significance and Impact of Study: Establishment of biopreservation as a method for extension of shelf life of meat products. [source] GAMMA IRRADIATION ON FROZEN AND PACKAGED HEADED SHRIMPJOURNAL OF FOOD QUALITY, Issue 4 2009V.K.G. ABREU ABSTRACT The objective of this work was to evaluate the effects of , irradiation (0, 2, 4 and 6 kGy doses), applied on frozen and packaged headed shrimps, on pathogenic Vibrio cholerae O1 and Salmonella enteritidis bacteria, as well as on some of the physical and sensory characteristics of this kind of food. The 6 kGy dose was highly efficient in inhibiting V. cholerae O1 and S. enteritidis and in decreasing lipid oxidation in shrimps compared with the nonirradiated product. Shrimp texture was not affected by any of the irradiation doses studied, but the lightness of the surface color increased in shrimps irradiated with 6 kGy compared with those irradiated with 2 kGy. Shrimps irradiated with 6 kGy showed lower overall acceptability than those irradiated with 2 kGy or were nonirradiated. The application of , irradiation in doses up to 6 kGy on frozen and packaged headed shrimps could improve the microbiological quality of this commodity. PRACTICAL APPLICATIONS The use of , irradiation has the potential to ensure safety effectively by inactivating bacteria, increasing shelf life and maintaining food quality without significant chemical changes in the food matrix. Besides, this process can be applied to frozen and packaged products. Thus, irradiation of frozen and packaged shrimps could benefit the local processing industry, which could offer the international market a high-quality product, with an additional safety treatment. [source] IMPROVING THE QUALITY AND SHELF LIFE OF TURKISH ALMOND PASTEJOURNAL OF FOOD QUALITY, Issue 4 2008ESRA CAPANOGLU ABSTRACT Almond paste is an economically valuable product produced from almonds, sugar and a small amount of water. Oxidative rancidity and oil separation are the major problems that are encountered in the paste products affecting the shelf life. Another problem appears to be drying on the surface of the product resulting in poor consumer acceptability. In this study, the formulation of product was altered by adding a commercial stabilizer, antioxidant mixture and maltose syrup to prevent undesirable quality changes during storage at 4C and 30C. Peroxide value, free fatty acid and Rancimat analysis showed that the addition of antioxidant mixture prevented oxidation effectively and improved sensory scores significantly (P , 0.05). Although stabilizer addition had a detrimental effect on the textural properties, samples that have maltose had high sensory scores. The results showed that incorporation of maltose syrup and antioxidant may improve the texture and shelf life of almond paste. PRACTICAL APPLICATIONS The available literature on almond paste is mainly focused on the microbiological quality of the product and the prevention of spoilage reactions by modifying packaging materials. However, there is no report on the optimization of the composition to extend the shelf life of almond paste. Turkish almond paste, a healthy and expensive dessert, is a specialty product that is manufactured by using traditional grinding equipment. However, the limited shelf life of this product decreases its export potential resulting in economical losses. Therefore, improved shelf life and quality of the product is of importance from the economical point of view. In our study, we aimed to improve the quality and shelf life of Turkish almond paste by modifying its formulation in order to minimize the undesirable changes that occur during storage. [source] Effectiveness of Radiation Processing for Elimination of Salmonella Typhimurium from Minimally Processed Pineapple (Ananas comosus Merr.)JOURNAL OF FOOD SCIENCE, Issue 3 2007Ravindranath Shashidhar ABSTRACT:, The microbiological quality of market samples of minimally processed (MP) pineapple was examined. The effectiveness of radiation treatment in eliminating Salmonella Typhimurium from laboratory inoculated ready-to-eat pineapple slices was also studied. Microbiological quality of minimally processed pineapple samples from Mumbai market was poor; 8.8% of the samples were positive for Salmonella. D10 (the radiation dose required to reduce bacterial population by 90%) value for S. Typhimurium inoculated in pineapple was 0.242 kGy. Inoculated pack studies in minimally processed pineapple showed that the treatment with a 2-kGy dose of gamma radiation could eliminate 5 log CFU/g of S. Typhimurium. The pathogen was not detected from radiation-processed samples up to 12 d during storage at 4 and 10 °C. The processing of market samples with 1 and 2 kGy was effective in improving the microbiological quality of these products. [source] Quality and Microbial Population of Cornish Game Hen Carcasses as Affected by Electron Beam IrradiationJOURNAL OF FOOD SCIENCE, Issue 7 2006C. Gomes ABSTRACT:, We evaluated the chemical and microbiological quality of Cornish game hen carcasses irradiated up to 7 kGy with a 10 MeV linear accelerator (dual beam configuration). Eighty frozen and vacuum packaged (approximately 0.45 kg) Cornish game hens (Gallus domesticus) were irradiated and stored in low-density polyethylene bags at 4 ± 1 °C for 21 d; nonirradiated chickens served as controls. Fat oxidation (in terms of malonaldehyde content) increased with storage time and dose for all chicken parts analyzed (breast, thigh, and skin). As expected, the skin had the highest level of fat oxidation while the breast samples had the lowest. Oxidation level in all samples exposed to 2 kGy reached a maximum on day 14. Sensory evaluation showed that irradiation caused significant textural toughening, and increased the redness of raw chicken meat. In terms of overall quality and aroma, lipid oxidation was not a major problem since it was not detected by the panelists. Irradiation significantly reduced the total viable microbial counts (TVC) in the breast and thigh samples. Exposure to 3-kGy dose decreased the TVC by 0.3-log cycles on the surface of the skin. In less than 14 d, the nonirradiated chicken carcasses had counts greater than 6 log CFU/50 cm2, while the 2 and 3 kGy irradiated samples reached these numbers only after 21 d of storage. Samples irradiated at 7 kGy had consistently the lowest counts (2.5 log CFU/50 cm2) throughout storage time. This study shows that irradiation up to 7 kGy and refrigerated storage (4 °C) inhibits microbial growth and extends shelf life of Cornish game hens without affecting consumers' acceptability. [source] Effect of lyophilisation, refrigerated storage and frozen storage on the coagulant activity and microbiological quality of Cynara cardunculus L. extractsJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 8 2008Luis Tejada Abstract BACKGROUND:Cheese-makers have traditionally kept vegetable coagulants refrigerated until use, even though little was known of their microbiological quality or coagulant activity during storage. This study aimed to assess the efficacy of lyophilisation, refrigerated storage and frozen storage of fresh vegetable extract as a means of standardising coagulant activity in terms of coagulation times, pH and microbiological quality. RESULTS:Neither the pH nor the coagulation time of lyophilised extracts was significantly modified during 1 year; however, changes were observed following frozen storage, and more notable following refrigerated storage. Lyophilisation of aqueous extracts prompted the destruction of most micro-organisms; low counts initially noted for total mesophiles, lactic acid bacteria and yeasts disappeared during the first few days of storage, due to low water activity. There was a generalised decrease in micro-organism counts during frozen storage. Refrigeration was found to be unsuitable for storing of cardoon extract; an increase of roughly 2 log unit counts was recorded in total mesophile, lactic acid bacteria, yeast and mould counts after 1 year of refrigerated storage. CONCLUSION:Refrigerated storage cannot be considered a suitable method for prolonged conservation of aqueous cardoon extract. Both lyophilisation and frozen storage of aqueous extracts proved ideal for prolonged storage of vegetable coagulant. Lyophilisation additionally had certain advantages over frozen storage. Copyright © 2008 Society of Chemical Industry [source] Evaluation of different varieties of cauliflower for minimal processingJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 2 2007Susana Sanz Abstract The impact of minimal processing technology on the sensory quality and the growth of micro-organisms in eight varieties of cauliflower packaged in four different films (one PVC and three P-Plus) was measured and quantified during more than 25 days of storage at 4 °C. Other important parameters such as weight loss and gas concentration in the packages were also determined. The composition of the atmosphere in the packages of minimally processed cauliflower depended on both the permeability of the film used for the packaging and the variety of cauliflower. When establishing shelf-life, loss of sensory quality was the deciding factor rather than loss of microbiological quality. The initial microbial load proved more important than the composition of the atmosphere inside the packages. In sensory evaluation the most important aspect was colour. In instrumental evaluation, coordinate b* was the main means of estimating shelf-life. The combination of P-Plus 120 film and varieties of cauliflower of large size and great vigour allowed the atmosphere inside the packages to have an O2 level below 10% and a CO2 level above 10%. That atmosphere composition proved essential for maintaining the sensory quality of minimally processed cauliflower. In these conditions, samples attained a shelf-life of more than 25 days. However, the different behaviours of the cauliflower varieties make it necessary to establish particular packaging conditions. The use of less permeable films than those used in this study, or the use of actively modified atmospheres, could be an alternative for those varieties that require special packaging conditions when processed using this technology. Copyright © 2006 Society of Chemical Industry [source] Electronic nose analysis of volatile compounds from poultry meat samples, fresh and after refrigerated storage,JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 3 2002Dorothy D, H Boothe Abstract Electronic nose technology has previously been applied to the assessment of the quality of red meats, pork and fish, but not poultry products. In the present study the ability of the electronic nose to assess the microbiological quality of raw poultry meat as a function of storage time and temperature was investigated. Four types of chicken pieces (boneless breast with and without skin, wings and thighs) were stored for up to 2 days at 13,°C (the maximum allowable temperature in poultry processing environments) or for up to 5 days at 4,°C (refrigeration temperature for raw poultry products prior to shipping or further processing). Saline rinses of meat samples were serially diluted in tryptic soy broth to 10,10. The rinses and their associated serial dilutions were analysed on an electronic nose with 12 metal oxide sensors in order to determine the specificity and sensitivity respectively of the assay. Principal component analysis (PCA) maps of the data confirmed that the electronic nose could differentiate volatile compounds associated with individual types of meat samples properly stored at 4,°C from those maintained at processing temperature, 13,°C, for a comparable time, even as early as day 1 of storage. Differences in headspace gases from any type of meat sample stored at one temperature could also be determined with increased storage time. However, data from samples stored at 4,°C clustered more tightly in PCA maps than those associated with samples maintained at 13,°C, indicating a greater diversity in volatile compounds at the higher temperature. We have shown herein that the electronic nose can detect changes in the volatile compounds associated with chicken meat based on product storage time and temperature; the technology can assess length of sample storage as well as deviation from refrigeration temperature. Published in 2002 for SCI by John Wiley & Sons, Ltd. [source] The microbiological quality of drinking water sold on the streets in Kumasi, GhanaLETTERS IN APPLIED MICROBIOLOGY, Issue 4 2003K. Obiri-Danso Abstract Aim: The aim of this study was to assess the microbiological quality of Ghanaian bottled and plastic-bagged drinking water sold on the streets of Metropolitan Kumasi, Ghana. Methods and Results: Eight bottled, 88 factory-filled plastic sachet and 40 hand-filled hand-tied polythene-bagged drinking waters were examined for the presence of heterotrophic bacteria total viable counts (TVCs), indicators of faecal contamination (total coliforms, faecal coliforms and enterococci) and for lead, manganese and iron. Heterotrophic bacteria were found in all three types of water with TVCs per millilitre ranging from 1 to 460 for bottled water, 2,6·33 × 105 for factory-bagged sachet water and 2·33 × 103,7·33 × 1012 for hand-filled hand-tied bagged water. None of the microbial indicators of faecal contamination were detected in bottled water, whereas 4·5% of the factory-bagged sachets contained total coliforms and 2·3% faecal coliforms, and 42·5% of the hand-filled hand-tied bags contained total coliforms, 22·5% faecal coliforms and 5% enterococci. Iron was found in all three types of drinking water but at concentrations well within the WHO recommendations. Lead and manganese were not detected. Conclusion: Ghanaian bottled water is of good microbiological quality but some factory-bagged sachet and hand-filled hand-tied polythene-bagged drinking water are of doubtful quality. Significance and Impact of the Study: Factory-bagged sachets and hand-filled hand-tied bags of drinking water sold in Ghana should be monitored for microbiological contamination, with the aim of raising standards in the industry and re-assuring the public. [source] | |||||||||||||