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Microbiological Properties (microbiological + property)
Selected AbstractsSoy Protein Fortification Affects Sensory, Chemical, and Microbiological Properties of Dairy YogurtsJOURNAL OF FOOD SCIENCE, Issue 7 2000M.A. Drake ABSTRACT: Chemical, microbiological, and sensory properties for low fat yogurts fortified with 0,1, 2.5, or 5% soy protein concentrate were determined through 1 mo storage at 5 °C. Yogurts were adjusted to equivalent total solids with nonfat dried milk. Microbiological counts, fermentation time, and final developed acidity were not affected by soy protein. Instrumental viscosity and sensory thickness, soy aroma, and soy flavor increased with soy protein addition (P 0.05). Soy flavor and aroma did not increase with storage time. Yogurt with 5% soy protein was darker, more chalky, and less sweet compared to control yogurt or yogurts with lower concentrations of soy protein (P 0.05). Yogurts with 1 or 2.5% soy protein were most similar to control yogurt. [source] Pantoea ananatis: an unconventional plant pathogenMOLECULAR PLANT PATHOLOGY, Issue 3 2009TERESA A. COUTINHO SUMMARY Pantoea ananatis causes disease symptoms in a wide range of economically important agricultural crops and forest tree species worldwide. It is regarded as an emerging pathogen based on the increasing number of reports of diseases occurring on previously unrecorded hosts in different parts of the world. Its unconventional nature lies in the fact that, unlike the majority of plant pathogenic microbes, P. ananatis is capable of infecting humans and occurs in diverse ecological niches, such as part of a bacterial community contaminating aviation jet fuel tanks and contributing to growth promotion in potato and pepper. Taxonomy: Bacteria; Gammaproteobacteria; family Enterobacteriaceae; genus Pantoea. Microbiological properties: Gram-negative; facultatively anaerobic; most strains are motile and produce a yellow pigment in culture; indole positive. Biology:Pantoea ananatis is a common epiphyte; it also occurs endophytically in hosts where it has been reported to cause disease symptoms and in hosts where no such symptoms have been described. Some strains are ice-nucleating, a feature which has been used as a biological control mechanism against some insect pests of agricultural crops and by the food industry. Disease symptoms:Pantoea ananatis infects both monocotyledonous and dicotyledonous plants. The symptoms are diverse depending on the host infected, and include leaf blotches and spots, die-back, and stalk, fruit and bulb rot. Biological control agent:Pantoea ananatis has both antifungal and antibacterial properties. These characteristics have the potential of being exploited by biological control specialists. [source] Xanthomonas axonopodis pv. citri: factors affecting successful eradication of citrus cankerMOLECULAR PLANT PATHOLOGY, Issue 1 2004James H. Graham SUMMARY Taxonomic status:, Bacteria, Proteobacteria, gamma subdivision, Xanthomodales, Xanthomonas group, axonopodis DNA homology group, X. axonopodis pv. citri (Hasse) Vauterin et al. Microbiological properties:, Gram negative, slender, rod-shaped, aerobic, motile by a single polar flagellum, produces slow growing, non-mucoid colonies in culture, ecologically obligate plant parasite. Host range:, Causal agent of Asiatic citrus canker on most Citrus spp. and close relatives of Citrus in the family Rutaceae. Disease symptoms:, Distinctively raised, necrotic lesions on fruits, stems and leaves. Epidemiology:, Bacteria exude from lesions during wet weather and are disseminated by splash dispersal at short range, windblown rain at medium to long range and human assisted movement at all ranges. Crop loss:, Severe infections cause defoliation, blemished fruit, premature fruit drop, die-back of twigs and general debilitation of the tree. Distribution:, Citrus canker is not present in all subtropical to tropical regions of citriculture in the world, so considerable regulatory efforts are expended to prevent the introduction and spread of X. axonopodis pv. citri into areas in the Americas, Australia and elsewhere, with climates conducive to the disease. Importance:, Limited strategies exist for suppression of citrus canker on more susceptible cultivars. Blemished fruit are unmarketable and exposed fruit are restricted in market access. The economic impact of loss of markets is much greater than that from yield and quality reductions of the crop. Useful websites:,http://doacs.state.fl.us/canker , http://www.apsnet.org/education/lessonsplantpath/citruscanker/top.htm , http://www.apsnet.org/online/feature/citruscanker/ , http://www.plantmanagementnetwork.org/pub/php/review/citruscanker/ , http://www.abecitrus.com.br/fundecitrus.html , http://www.biotech.ufl.edu/PlantContainment/canker.htm , http://www.aphis.usda.gov/oa/ccanker/ . [source] Xanthomonas citri: breaking the surfaceMOLECULAR PLANT PATHOLOGY, Issue 3 2003Asha M. Brunings SUMMARY Taxonomy: Bacteria; Proteobacteria, Gammaproteobacteria; Xanthomonadales; Xanthomonadaceae, Xanthomonas. Microbiological properties: Gram-negative, obligately aerobic, straight rods, motile by a single polar flagellum, yellow pigment. Related species:X. campestris , X. axonopodis , X. oryzae , X. albilineans . Host range: Affects Rutaceous plants, primarily Citrus spp., Fortunella spp., and Poncirus spp., world-wide. Quarantined pathogen in many countries. Economically important hosts are cultivated orange, grapefruit, lime, lemon, pomelo and citrus rootstock. Disease symptoms: On leaves, first appearance is as oily looking, 2,10 mm, similarly sized, circular spots, usually on the abaxial surface. On leaves, stems, thorns and fruit, circular lesions become raised and blister-like, growing into white or yellow spongy pustules. These pustules then darken and thicken into a light tan to brown corky canker, which is rough to the touch. On stems, pustules may coalesce to split the epidermis along the stem length, and occasionally girdling of young stems may occur. Older lesions on leaves and fruit tend to have more elevated margins and are at times surrounded by a yellow chlorotic halo (that may disappear) and a sunken centre. Sunken craters are especially noticeable on fruit, but the lesions do not penetrate far into the rind. Defoliation and premature abscission of affected fruit occurs on heavily infected trees. Useful websites: Some chemical and microbiological properties of ghee produced in Eastern AnatoliaINTERNATIONAL JOURNAL OF DAIRY TECHNOLOGY, Issue 3 2008AYSEGUL KIRAZCI Some properties of 30 ghee samples produced in Eastern Anatolia in Turkey were evaluated. Lipolytic bacteria and yeast,mould counts ranged from undetectable to 9.9 × 105 and 6.9 × 105 cfu/g, respectively. Most of the samples showed higher free fatty acids (FFA) and peroxide values (PV) than the limits mentioned in International Dairy Federation standards. Storage at 5°C for 30 days was not sufficient to stop the lipolytic and yeast,mould growth and lipid oxidation of the samples. Ghee samples with considerably higher trans -C18 : 1 and trans -C18 : 2 fatty acids contents were considered to be adulterated with hydrogenated oils. It is recommended that specific attention should be given to technology transfer and the education of traditional dairy product manufacturers. [source] Storage stability of a high dietary fibre powder from orange by-productsINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 4 2009Juana Fernández-López Summary The goal of this investigation was to evaluate the effects of storage time and conditions on the physicochemical and microbiological properties of a high dietary fibre powder (HDFP). HDFP for this study was manufactured from orange juice industry by-products. The storage period was 11 months and samples were stored under vacuum or air exposure and under dark or light exposure. The HDFP is a stable product (based on chemical, microbiological and physicochemical properties) with large amounts of dietary fibre (71.62 ± 0.24 g 100 g,1 dry sample) and polyphenols content (40.67 ± 0.45 mg g,1 dry sample). Hesperidin is the major compound identified in HDFP (higher than 50% of total phenolic compounds). The packaging material used protects the HDFP only up to 6 months. After this time, the increase in moisture content decreases the quality of the product. The best storage conditions are packaging under vacuum and darkness. Both conditions preserve the colour of the fibres probably by means of avoiding pigment degradation. [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]
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