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Microbial Quality (microbial + quality)
Selected AbstractsEffects 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] Shelf Life and Microbial Quality of Fresh-cut Mango Cubes Stored in High CO2 AtmospheresJOURNAL OF FOOD SCIENCE, Issue 1 2005Jutatip Poubol ABSTRACT: Fresh-cut,Carabao'and,Nam Dokmai'mango cubes were stored in air or in high CO2 atmospheres (3%, 5%, and 10%) at 5 °C and 13 °C. Freshly sliced,Carabao'mango cubes had a lower respiration rate and total bacterial count and higher L-ascorbic acid content and firmness than,Nam Dokmai'mango cubes. The shelf life of fresh-cut mango, based on browning discoloration and water-soaked appearance, was 6 d at 5 °C and 4 d at 13 °C for,Carabao'and 2 d at 5 °C and less than 1 d at 13 °C for,Nam Dokmai'. High CO2 atmospheres retarded the development of water-soaked,Carabao'cubes at 5 °C and 13 °C and,Nam Dokmai'cubes at 5 °C. Texture of,Carabao'cubes was enhanced by high CO2, but ethanol and L-ascorbic acid contents were not affected at 5 °C and 13 °C. Total bacterial count was lower in,Carabao'cubes than in,Nam Dokmai'cubes during storage at both temperatures, and a 10% CO2 only reduced the bacterial count on,Carabao'and,Nam Dokmai'cubes stored at 13 °C. Bacterial flora in,Nam Dokmai'mango cubes consisted mostly of Gram-negative rods assigned primarily to phytopathogenic bacteria such as Pantoea agglomerans and Burkholderia cepacia. The genera of bacteria isolated from cubes stored in 10% CO2 were similar to those from cubes on the initial day. [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] 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] THE EFFECT OF PRETREATMENT OF SHREDDED CELERIAC USING SOLUTIONS OF ENZYMATIC BROWNING INHIBITORS ON THE QUALITY OF MINIMALLY PROCESSED PRODUCTJOURNAL OF FOOD QUALITY, Issue 5 2007BIETA, RADZIEJEWSKA-KUBZDELA EL ABSTRACT The study investigated the effect of soaking celeriac flakes in solutions containing various concentrations of enzymatic browning inhibitors on the quality of stored minimally processed product. Ascorbic acid (0.2,0.5%), 4-hexylresorcinol (0.003,0.01%), sodium chloride (0.1,0.5%) and sodium lactate (2,3%) were used as browning inhibitors. On the basis of the conducted tests, it was found that among the applied browning inhibitors, only ascorbic acid had an advantageous effect on the quality of stored celeriac flakes. Along with an increase in its concentration in the solution (0.2,0.5%) used for the pretreatment of the flakes, the value of color parameter a* decreased, while the value of parameter b* increased. At the concentration of ascorbic acid in the solution exceeding 0.25%, flake color in the sensory examination was evaluated as desirable. An increase of ascorbic acid concentration in the solution in the range from 0.2 to 0.4% resulted in a decrease in the total mesophilic and psychrophilic bacteria counts, respectively, by 3 and 1 log cfu/g of the stored product. PRACTICAL APPLICATIONS Minimal processing of celeriac provides convenience for consumers and many economic benefits for producers. Minimal processing of celeriac can induce disadvantageous changes in tissue, which may lead to darkening of the flakes and deterioration of product sensory attributes. Moreover, shredded raw material constitutes an excellent medium for the development of microorganisms. This article contains information about the effectiveness of enzymatic browning inhibitors for extending the shelf life of celeriac flakes. We show a range of concentrations of inhibitors, which improve the preservation of color, intrinsic taste and microbial quality of minimally processed celeriac. [source] | ||||||||||