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Microbial Load (microbial + load)
Selected AbstractsPotential Application of Hot Rehydration Alone or in Combination with Hydrogen Peroxide to Control Pectin Methylesterase Activity and Microbial Load in Cold-stored Intermediate-moisture Sun-dried FigsJOURNAL OF FOOD SCIENCE, Issue 3 2004D. DEMIRBÜKER ABSTRACT: Sun-dried figs contain a considerable amount of pectin methylesterase (PME) activity (22 JAM COOH/ min/g). The enzyme causes softening and loss of desired gummy texture in cold-stored intermediate-moisture (IM) sun-dried figs brought to a 28% to 29% moisture range. Partial reduction of PME activity (28%) delayed undesirable textural changes in IM figs rehydrated at 80 °C for 16 min. The heat treatment did not cause a considerable reduction in microbial load. However, the addition of 2.5% H2O2 to the rehydration medium at 80 °C reduced the initial total mesophilic aerobic count of figs by at least 90% and turned the figs from a brown color to a desirable and stable yellow-light brown. The in situ fig catalase remains after rehydration at 80 °C. Thus, by reducing the contact period of figs with H2O2 or by pureeing figs, it is possible to eliminate residual H2O2 and to obtain safe and SO2-free light-colored fig products. [source] Determination of biochemical properties of foam-mat dried mango powderINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 8 2010Dattatreya M. Kadam Summary Investigations were carried out to see the impact of drying air temperature (65, 75 and 85 °C) and milk as foaming agent in different concentration levels (0%, 10%, 15%, 20% and 25%) on the chemical properties of foam-mat dried mango juice powder. Chemical properties such as total sugars, ascorbic acid, total carotenes, minerals, total acid, pH, total soluble solids (TSS) and microbial load (fungal and bacterial) of foam-mat dried mango powder were determined. Data were analysed as per two-way anova, Duncan's multiple range test and l.s.d. of AgRes Software statistical package. Almost all chemical properties show decreasing trend with increase in drying air temperature. Microbial load was not detected in foam-mat dried mango powder. It was found that addition of 10% milk as foaming agent and drying at 65 °C temperature gave better results. [source] Quality of thawed deepwater pink shrimp (Parapenaeus longirostris) treated with melanosis-inhibiting formulations during chilled storageINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 9 2007Maria Elvira López-Caballero Summary This work investigates how the treatment of thawed deepwater pink shrimp (Parapenaeus longirostris) with several melanosis-inhibiting formulations, affects the quality of the shrimp during chilled storage. Formulations were as follows: a formulation containing 4-hexylresorcinol (0.1 and 0.05%), in combination with organic acids and chelating agents, a commercial formula based on sulphites, and a mixture of gluconic acid and commercial sulphites. No noticeable differences were observed for both trimethylamine and total volatile bases during chilled storage. pH evolution was irrespective of the treatment condition. Microbial load enlarged after the sixth day of chilled storage. Higher total bacteria counts were associated with the control and sulphite treatment conditions, while lactic acid bacteria growth seemed to be favoured under formulations based on 4-hexylresorcinol. The appearance of melanosis occurred more rapidly in control shrimp or in shrimp treated with commercial sulphites. 4-hexylresorcinol formulations preserved the quality of thawed shrimp and could replace traditional sulphites. [source] Determination of biochemical properties of foam-mat dried mango powderINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 8 2010Dattatreya M. Kadam Summary Investigations were carried out to see the impact of drying air temperature (65, 75 and 85 °C) and milk as foaming agent in different concentration levels (0%, 10%, 15%, 20% and 25%) on the chemical properties of foam-mat dried mango juice powder. Chemical properties such as total sugars, ascorbic acid, total carotenes, minerals, total acid, pH, total soluble solids (TSS) and microbial load (fungal and bacterial) of foam-mat dried mango powder were determined. Data were analysed as per two-way anova, Duncan's multiple range test and l.s.d. of AgRes Software statistical package. Almost all chemical properties show decreasing trend with increase in drying air temperature. Microbial load was not detected in foam-mat dried mango powder. It was found that addition of 10% milk as foaming agent and drying at 65 °C temperature gave better results. [source] Periodontal infection profiles in type 1 diabetesJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 12 2006Evanthia Lalla Abstract Objectives: We investigated the levels of subgingival plaque bacteria and serum IgG responses in patients with type 1 diabetes and non-diabetic controls of comparable periodontal status. Material and Methods: Fifty type 1 diabetes patients (mean duration 20.3 years, range 6,41) were age-and gender-matched with 50 non-diabetic individuals with similar levels of periodontal disease. Full-mouth clinical periodontal status was recorded, and eight plaque samples/person were collected and analysed by checkerboard hybridization with respect to 12 species. Homologous serum IgG titres were assessed by checkerboard immunoblotting. In a sub-sample of pairs, serum cytokines and selected markers of cardiovascular risk were assessed using multiplex technology. Results: Among the investigated species, only levels of Eubacterium nodatum were found to be higher in diabetic patients, while none of the IgG titres differed between the groups, both before and after adjustments for microbial load. Patients with diabetes had significantly higher serum levels of soluble E-selectin (p=0.04), vascular cell adhesion molecule-1 (VCAM-1; p=0.0008), adiponectin (p=0.01) and lower levels of plasminogen activator inhibitor-1 (PAI-1; p=0.02). Conclusions: After controlling for the severity of periodontal disease, patients with type 1 diabetes and non-diabetic controls showed comparable subgingival infection patterns and serum antibody responses. [source] REUSE OF SUCROSE SYRUP IN PILOT-SCALE OSMOTIC DEHYDRATION OF APPLE CUBESJOURNAL OF FOOD PROCESS ENGINEERING, Issue 2 2002A. VALDEZ-FRAGOSO ABSTRACT Osmotic dehydration (OD) treatments of apple cubes were carried out in a pilot plant, which consisted of an OD vessel, a filter, a vacuum evaporator, and recirculating pumps. The osmotic solution (OS) was maintained at 59.5 ± 1.5 °Brix and 50C by reconcentration in the evaporator, and suspended particles were eliminated by filtration. OS was reused to process 20 batches of apple cubes, maintaining a constant OS/fruit ratio of 5/1 (w/w) by addition of new OS. Evolution of pH, titratable acidity, soluble solids, water activity, color, reducing sugars, and microbial load in the OS was evaluated along the OD process. The OD parameters and the apple color were determined. Values of the physicochemical properties of the OS stabilized after 10 treated batches. A microbial load of 2590 ± 330 CFU/mL was observed in the OS at the end of 20 OD treatments. Water loss, solids gain and color of dehydrated apple cubesobtained in OD process with reuse of the OS were similar to those found in an OD process carried out with a nonrewed OS. [source] INFLUENCE 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] EFFECTS OF ANTIOXIDANTS ON IRRADIATED BEEF COLORJOURNAL OF FOOD QUALITY, Issue 3 2010LAKSHMANAN RAMAMOORTHI ABSTRACT Fresh beef was dipped into ascorbic acid (AA; 500 ppm), butylated hydroxyanisole (BHA, 150 ppm), butylated hydroxytoluene (BHT, 100 ppm) or propyl gallate (PG; 100 ppm); control samples were dipped in deionized water. Samples were vacuum packaged, then irradiated (0, 1.25 or 2.50 kGy). After irradiation, samples were stored (0, 7 or 14 days) at 4C. Color was assessed instrumentally (L*, a*, b*values, hue angles, chroma) and visually. All antioxidants increased L*value by two units (lighter); however, irradiation dose had no effect. Irradiation increased wet dog and rancid odors of beef; however, it decreased sour odor, a*value, chroma and hue angle, and increased visual green and brown colors, indicating that it reduced redness and color intensity. Antioxidants reduced L*(decreased lightening) and a*values (redness) compared to controls. BHA had the greatest effect on a*value. AA decreased visual green color the most; however, BHA and BHT were also effective. Antioxidants had inconsistent effects on b*value, chroma and hue angle. Storage decreased L*and a*values, and chroma. BHA and PG were most effective at maintaining low thiobarbituric acid-reactive substances when samples were irradiated. PRACTICAL APPLICATIONS Irradiation has the potential to reduce microbial load, increasing both the safety and shelf life of red meat products; however, it has the potential to damage fresh meat color, resulting in unacceptable discoloration. Irradiation can increase off-odors (wet dog, rancid) of beef; however, it can decrease sour odor, instrumental measures of red color, and increase visual green and brown colors. Use of antioxidants including ascorbic acid, butylated hydroxytoluene, butylated hydroxyanisole and propyl gallate can help maintain the color of irradiated beef held in refrigerated storage for up to 2 weeks. [source] Development and Evaluation of an Ozonated Water System for Antimicrobial Treatment of Durum WheatJOURNAL OF FOOD SCIENCE, Issue 7 2009B. Dhillon ABSTRACT:, Ozonated water is reported to be effective in reducing the microbial load in foods such as fruits, vegetables, and grains. Ozonated water may be an effective alternative to chlorinated water in treating durum wheat before milling. Therefore, durum wheat was washed with ozonated water and analyzed for yeast and mold count (YMC) and aerobic plate count (APC). A system for producing and monitoring ozonated water was developed. The effect of water quality (tap, distilled, and ultra-pure), temperature (7, 15, and 25 °C), and pH (2, 4, and 6.5) was evaluated on the following: steady-state dissolved ozone concentration, ozone decay constant, half-life, mass transfer coefficient, equilibrium ozone concentration, and solubility ratio. The study of these parameters was important to attain a stable, high dissolved ozone concentration at the outset of washing and to have information for system improvement and scale-up. A 1% acetic acid solution (pH 2) at 15 °C resulted in high dissolved ozone concentration (21.8 mg/L) and long half-life (9.2 min). Subsequently, wheat was washed with 5 wash water types: distilled water, ozonated water (16.5 mg/L), chlorinated water (700 mg/L), acetic acid solution (1%), and acetic acid + ozonated water (1%, 20.5 mg/L). The treated samples were analyzed for YMC and APC. The acetic acid + ozonated water treatment was the most effective, with a reduction of 4.1 and 3.2 log10 colony forming units/g in YMC and APC, respectively. Though ozonated water was not very effective alone, it was useful in combination with acetic acid. [source] A Continuous High Pressure Carbon Dioxide System for Microbial Reduction in Orange JuiceJOURNAL OF FOOD SCIENCE, Issue 5 2005Dilek Kincal ABSTRACT: A continuous high-pressure carbon dioxide system, run at ambient conditions, was tested on its performance in reducing both natural and inoculated microbial loads. The prototype system continuously processes orange juice with carbon dioxide (CO2) at high pressures. A central composite design was originally used to examine the variables of pressure, residence time, and CO2/juice ratio. For microbial reduction, residence time was the major factor followed by pressure. The CO2/juice ratio showed no influence on microbial load, and in this equipment, was difficult to control. The unit was able to cause a 5-log reduction of the natural flora in spoiled juice, and could attain a 5-log decrease in numbers of pathogenic Escherichia coli O157:H7, Salmonella typhimurium, and Listeriamonocytogenes. No viable cells of E. coli O157:H7 orS. typhimurium were cultured after the treated juices were stored at room temperature (22 °C) for 14 d. Thus, non-thermal pathogen reduction is possible with this system. [source] Effects of Hot Rehydration in the Presence of Hydrogen Peroxide on Microbial Quality, Texture, Color, and Antioxidant Activity of Cold-stored Intermediate-moisture Sun-dried FigsJOURNAL OF FOOD SCIENCE, Issue 3 2005Dilek Demirbüker ABSTRACT: Pectin methylesterase (PME) causes considerable softening in intermediate-moisture (IM) figs rehydrated at 30°C and cold stored at 28% to 29% moisture content. Rehydration of figs at 80°C for 16 min inactivated PME partially (25,30%), but this did not prevent the softening over 3 mo of cold storage. Also, heating did not reduce the microbial load of figs significantly and increased their browning. In contrast, rehydration of figs 1st in 2.5% H2O2 at 80°C for 8 min and then in water at 80°C for 8 min reduced the microbial load of IM figs significantly, turned their brown color to yellow-light brown, and maintained their desired textural properties. The residual H2O2 in IM figs decomposed in 3 or 1.5 wk by the in situ catalase or by application of the iron (II) sulfate-ascorbic acid residue elimination method, respectively. Hot rehydration did not affect the antioxidant activity of IM figs, but treatment of figs with H2O2 increased their antioxidant activity slightly. These results indicate that the hot rehydration of figs in the presence of H2O2 and cold storage may be applied to obtain safe and SO2 -free light-colored IM fig products. [source] Potential Application of Hot Rehydration Alone or in Combination with Hydrogen Peroxide to Control Pectin Methylesterase Activity and Microbial Load in Cold-stored Intermediate-moisture Sun-dried FigsJOURNAL OF FOOD SCIENCE, Issue 3 2004D. DEMIRBÜKER ABSTRACT: Sun-dried figs contain a considerable amount of pectin methylesterase (PME) activity (22 JAM COOH/ min/g). The enzyme causes softening and loss of desired gummy texture in cold-stored intermediate-moisture (IM) sun-dried figs brought to a 28% to 29% moisture range. Partial reduction of PME activity (28%) delayed undesirable textural changes in IM figs rehydrated at 80 °C for 16 min. The heat treatment did not cause a considerable reduction in microbial load. However, the addition of 2.5% H2O2 to the rehydration medium at 80 °C reduced the initial total mesophilic aerobic count of figs by at least 90% and turned the figs from a brown color to a desirable and stable yellow-light brown. The in situ fig catalase remains after rehydration at 80 °C. Thus, by reducing the contact period of figs with H2O2 or by pureeing figs, it is possible to eliminate residual H2O2 and to obtain safe and SO2-free light-colored fig products. [source] Microbial and Sensory Assessment of Milk with an Electronic NoseJOURNAL OF FOOD SCIENCE, Issue 2 2002F. Korel ABSTRACT: An electronic nose (e-nose) was used to assess milk odor inoculated with Pseudomonas fluorescens or Bacillus coagulans, and odors were correlated with microbial loads and sensory scores. Sterile whole, reduced-fat, and fat-free milk were inoculated, stored at 1.7, 7.2, and 12.8 °C, and evaluated at d 0, 3, 5, 7, and 10 by e-nose and sensory panel. Aerobic plate counts were performed. E-nose readings, microbial counts, and sensory data were analyzed using discriminant function analysis. The e-nose discriminated differences in odor due to microbial load and sensory data. This may lead to a rapid method for determining sensory evaluation and microbial loads of milk. [source] Quality of grated carrot (var. Nantes) packed under vacuumJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 3 2007Ada MCN Rocha Abstract The quality of grated carrot (variety Nantes) was evaluated throughout 10 days of storage in two different atmospheres: air and vacuum at 2 °C. The parameters of quality were microbiological and physico-chemical. Sensory evaluation of vacuum-packed grated carrots was performed after the microbiology study. The objective was to study the use of a vacuum for preservation of this type of product. The use of a vacuum was sufficiently promising with respect to the capacity to extend the shelf life of grated carrot by reducing microbial load and by minimising physico-chemical changes. The shelf life of grated carrot under vacuum was extended to 8 days at 2 °C. Copyright © 2006 Society of Chemical Industry [source] The effect of gamma irradiation on the microbial load, mineral concentration and sensory characteristics of liquorice (Glycyrrhiza glabra L)JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 1 2003Mahfouz Al-Bachir Abstract Ground liquorice roots were exposed to various doses (0, 5, 10, 15 and 20,kGy) of gamma radiation from a 60Co source. Irradiated and non-irradiated samples were stored at room temperature. Microbial population, viscosity, concentrations of some minerals and the sensory properties of the extracts were evaluated after 0 and 12 months of storage. Tests carried out immediately after irradiation showed that the microbial count had been reduced and that the dose required to reduce the count by 1 log cycle (D10) was about 2,kGy. No effect was observed on the total dissolved solids in extracts of liquorice roots. Glycyrrhizinic acid concentration in the extracts and the viscosities of suspensions produced from irradiated roots were lower than those from non-irradiated ones. Sensory evaluation indicated that there were no significant differences (P,<,0.05) in colour, taste or flavour between extracts produced from irradiated and non-irradiated roots. However, after 12 months of storage, some mineral ion (Na+, Ca2+ and K+) concentrations in extracts produced from irradiated roots were lower than in those from non-irradiated ones; no significant differences (P,<,0.05) in viscosity were found between suspensions of irradiated and non-irradiated roots. © 2002 Society of Chemical Industry [source] Odorous compounds in paperboard as influenced by recycled material and storagePACKAGING TECHNOLOGY AND SCIENCE, Issue 4 2001Gottfried Ziegleder Abstract Many volatile compounds can be identified in unprinted paperboard by means of steam distillation in combination with capillary gas chromatography, mass spectrometry and olfactometry. Paperboards produced with recycled material exhibit additional volatiles which partly contribute to off-odours. Using sniffing techniques, benzaldehyde, acetophenone, 1-octen-3-ol, 1-octen-3-one, 2-nonenal, methylguajacol, butanoic and 3-methyl butanoic acid were identified as the most odorous volatiles. The aromatic substances mainly exude from inks and printing solvents in waste materials used for paperboard manufacturing. During storage under controlled conditions, the microbial load of paperboard decreased slightly, and no odorous metabolic products were generated. Copyright © 2001 John Wiley & Sons, Ltd. [source] Application of prospective probionts at early stages of Atlantic cod (Gadus morhua L.) rearingAQUACULTURE RESEARCH, Issue 10 2010Hélène L Lauzon Abstract This work aimed at validating the use of two prospective probionts (Arthrobacter sp. and Enterococcus sp.) at early stages of cod (Gadus morhua L.) rearing. Ova at late post-fertilized stage and larvae during their first 4 weeks of life were bathed with both probionts, isolated previously from the cod-rearing environment. This treatment was compared with groups fed rotifers supplemented with a commercial probiotic (Remus®) and those untreated. Microbiological analyses (total viable counts, presumptive Vibrio and lactic acid bacteria) were performed in rearing systems and larval survival, growth and development were assessed. Larval development was evaluated by proteolytic activity of larval lysates and immunological analysis of important proteins: apolipoprotein A-I, haemoglobin, C-reactive protein, C3 and cod serum proteins. Bacterial bathing led to a significantly higher larval weight, length and culturable microbial load in larval gastrointestinal (GI) tract when compared with the control and Remus groups. Development occurred earlier in bathed larvae. However, their survival was negatively affected compared with the control group, but was significantly higher than for the Remus group. The non-pathogenicity of both probionts was demonstrated by intraperitoneal injection of 13 g cod juveniles. The results suggest that Arthrobacter and Enterococcus probionts affected the larval GI microbiota and contributed to growth, development and digestion, either directly or indirectly. [source] Detection Methods for Irradiated FoodsCOMPREHENSIVE REVIEWS IN FOOD SCIENCE AND FOOD SAFETY, Issue 1 2009Sulaxana Kumari Chauhan ABSTRACT:, Proper control of irradiation processing of food is very critical to facilitate international trade of irradiated foods and to enhance consumer confidence, consumer choice, and safety. Analytical detection of radiation-processing of food is very important to implement quality control at all levels. An ideal detection method should measure a specific radiation effect, which is proportional to the dose and should not be affected by processing parameters and storage conditions or the length of time between irradiation processing and analysis. The detection of irradiated foods is mainly based on radiolysis of lipids, modification of amino acids, modification of DNA, modification of carbohydrates, formation of free radicals, release of hydrogen gas, alterations in microbial load, measurement of biological difference, and other physical methods. [source] USING GELATIN-BASED ANTIMICROBIAL EDIBLE COATING TO PROLONG SHELF-LIFE OF TILAPIA FILLETSJOURNAL OF FOOD QUALITY, Issue 3 2002CHAN-YIN OU Skinless tilapia (Dreochromis niloticus x D. aureus) fillets were covered with a gelatin coating containing benzoic acid as an antimicrobial agent. Benzoic acid content of fish fillets was used to estimate the amount of gelatin coated on fillet surface, and it was found that the gelatin contents were between 16.3 mg and 17.3 mg per g of fillets. Aerobic and anaerobic microbial loads, volatile basic nitrogen (VBN) contents, and sensory evaluation were used as indicators to survey the feasibility of an antimicrobial gelatin coating to prolong the shelf-life of tilapia fillets under refrigeration. After 7 days of storage under refrigeration, tilapia fillets coated with gelatin containing benzoic acid had acceptable VBN contents, increased moderately in microbial loads, and showed no significant sensory difference (P < 0.05) from fresh fillets. The results indicate that an antimicrobial gelatin coating is suitable for preservation of tilapia fillets. [source] Quality Attributes and Microbial Storage Stability of Caviar from Cultivated White Sturgeon (Acipenser transmontanus)JOURNAL OF FOOD SCIENCE, Issue 1 2010Joong-Han Shin ABSTRACT:, Caviar was prepared from white sturgeon (Acipenser transmontanus) roe by adjusting the water phase salt (WPS) to 4.0% to 6.3% by adding food grade NaCl. Fish were obtained from 2 different farms from the Inland Northwest (N,= 5). Salt was absorbed at a different rate and to a different extent by roe from different fish. The lipid content in the fish roe varied from 10.2% to 14.4% (w/w), with palmitic acid and oleic acid being the most abundant saturated and monounsaturated fatty acids present, respectively. The caviar contained high levels of polyunsaturated fatty acids (PUFA) (35% to 37%) with docosahexanoic acid being the most abundant ,-3 long chain fatty acid. There were no significant differences in microbial storage stability for caviars from different fish stored at 3 °C. However, for caviar stored at 7 °C, there was less growth of,Listeria monocytogenes,(using a cocktail of ATCC 19114, 7644, 19113 strains) in 2 samples (2B46 and 0F05) until day 20. In 2 other samples (453F and 2519), which had lower initial microbial loads, less overall microbial growth was observed, indicating that culture and harvest practices result in compositional differences between fish, which may impact both product composition and storage stability. [source] A Continuous High Pressure Carbon Dioxide System for Microbial Reduction in Orange JuiceJOURNAL OF FOOD SCIENCE, Issue 5 2005Dilek Kincal ABSTRACT: A continuous high-pressure carbon dioxide system, run at ambient conditions, was tested on its performance in reducing both natural and inoculated microbial loads. The prototype system continuously processes orange juice with carbon dioxide (CO2) at high pressures. A central composite design was originally used to examine the variables of pressure, residence time, and CO2/juice ratio. For microbial reduction, residence time was the major factor followed by pressure. The CO2/juice ratio showed no influence on microbial load, and in this equipment, was difficult to control. The unit was able to cause a 5-log reduction of the natural flora in spoiled juice, and could attain a 5-log decrease in numbers of pathogenic Escherichia coli O157:H7, Salmonella typhimurium, and Listeriamonocytogenes. No viable cells of E. coli O157:H7 orS. typhimurium were cultured after the treated juices were stored at room temperature (22 °C) for 14 d. Thus, non-thermal pathogen reduction is possible with this system. [source] Microbial and Sensory Assessment of Milk with an Electronic NoseJOURNAL OF FOOD SCIENCE, Issue 2 2002F. Korel ABSTRACT: An electronic nose (e-nose) was used to assess milk odor inoculated with Pseudomonas fluorescens or Bacillus coagulans, and odors were correlated with microbial loads and sensory scores. Sterile whole, reduced-fat, and fat-free milk were inoculated, stored at 1.7, 7.2, and 12.8 °C, and evaluated at d 0, 3, 5, 7, and 10 by e-nose and sensory panel. Aerobic plate counts were performed. E-nose readings, microbial counts, and sensory data were analyzed using discriminant function analysis. The e-nose discriminated differences in odor due to microbial load and sensory data. This may lead to a rapid method for determining sensory evaluation and microbial loads of milk. [source] Effect of cut-type on quality of minimally processed papayaJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 12 2008A Carla SJ Argañosa Abstract BACKGROUND: This research was undertaken to study the effects of different cut-types (cube, parallelepiped, cylinder and sphere) on the quality and shelf-life of papaya cv. Sunrise Solo. Physicochemical analyses were carried out during 10 days of storage at 4 °C to determine colour, firmness, pH, titratable acidity, total soluble solids, weight loss and vitamin C content. Microbiological analysis and sensory evaluation were also performed. RESULTS: Papaya spheres (1.55 cm radius) presented the most favourable physicochemical and microbiological properties (smaller changes in colour parameters L*, a*, b*, chroma and hue angle, firmer texture, lower increase in pH, higher titratable acidity, almost constant total soluble solids, reduced weight loss, high vitamin C content and lower microbial loads) and sensory characteristics on day 10, while papaya cubes (1.4 cm side) proved to be the least acceptable. CONCLUSION: The results of physicochemical, microbiological and sensory analyses performed on different cut-types of papaya indicated acceptable fresh-cut produce during 10 days of storage at 4 °C. The potential shelf-life at 4 °C is therefore 10 days, provided that no contamination occurs in the postharvest period and during minimal processing operations. Copyright © 2008 Society of Chemical Industry [source] | |||||||||||||