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Showing 1 to 20 of 83 for “"water activity"”.
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Physical Aging, Solubility, and Water Activity of Selected Disaccharides
For both experiments, the Tg onset, midpoint, and endpoint measured from the heat flow in SDSC, and the total and reversing heat flows in MDSC slightly increased with longer aging times and the Tg calculated for SDSC decreased whereas Tg calculated for MDSC slightly increased with aging time. In …
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Prediction of Water Activity in Cured Meat using Microwave Spectroscopy
… = 0.41. The second approach is to determine water activity (aw) in cured meat, which is the parameter that describes available water for microorganisms and influences different chemical reactions in the product. For the cured meat industry, aw is the only moisture related measurement that is …
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Reduced Water Activity and the Development of Stress in Salmonella Typhimurium 7136
Made available in DSpace on 2014-12-13T19:47:42Z (GMT). No. of bitstreams: 1 7811304.pdf: 4769910 bytes, checksum: d12e5fa89a98d695ea2dc904a3ccabae (MD5) Previous issue date: 1978
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Survival of encapsulated probiotic bacteria during storage at low water activity at ambient temperature
… of storage at 25oC (ambient temperature) at low water activities (aw). Three probiotic bacteria (Bifidobacterium animalis ssp. lactis Bb12, Bifidobacterium longum and Lactobacillus acidophilus) and one strain of most sensitive lactic acid bacteria (L. lactis ssp. cremoris) to acid and bile …
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The Physiological Response of Staphylococcus Aureus Mf-31 to Conditions of Reduced Water Activity
… was able to grow in environments at reduced water activity (a(,w)) was investigated. This project was approached by studying the influence of reduced a(,w) on the intracellular free amino acid pools, amino acid transport, glutamine synthesis, and proline oxidation in S. aureus. In addition, …
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Separating the effects of water activity and humectant on the growth of staphylococcus aureus
Thesis (B.S.)--Massachusetts Institute of Technology, Dept. of Chemical Engineering, 1976.
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Effect of glycerol and water activity on the processing and properties of egg white-based bioplastics
… a first study, the effects of plasticizer type (water and glycerol (GLY)) and amount (0.34, 0.48 and 0.64 Aw and 0, 35, 40 and 45% GLY) on the thermoplasticization of the egg white protein (EWP) were investigated using thermal studies, gravimetric analysis, and morphological studies. The results …
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Thermal Modeling of Vacuum Assisted Steam Pasteurization for Improved Product Safety of Low Water Activity Foods
… method used to kill harmful pathogens on low water activity foods (LWAFs). During this treatment process it is generally believed that the steam will quickly penetrate through the small gaps within a package of product and condense on the surfaces leading to efficient heat transfer. Through …
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Impacts of inoculation strategy on survival of Salmonella enterica and Enterococcus faecium at low water activity on dry peppercorn and cumin seeds
Salmonella contamination of spices and other low water activity foods is a growing concern for the food industry due to increased frequency of salmonellosis outbreaks and detection-based product recalls. The impact of inoculation preparation on the survival of a Salmonella enterica and its proposed …
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Impacts of low-water activity food type on inactivation kinetics and models of foodborne pathogens treated with low-temperature, vacuum-assisted steam processing
Low water activity foods (LWAF), specifically nuts and dried fruits, have been generally considered safe because they do not support the growth of foodborne pathogens. However, many pathogens have been noted to survive in LWAF for considerable periods of time, and a number of recent outbreaks and …
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Critical Quality Attributes of Topical Semi-solid Dosage Forms: Solvent Activity
… formulations contain solvent systems (water, ethanol, propylene glycol, glycerol and liquid chemical permeation enhancers) but the significance of solvent activity (thermodynamic solvent properties) on product performance has not been investigated so far, to be translated into a quality …
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The Effects of Solutes, Polymers and Their Mixtures on Mold Conidia Germination
Water activity (Aw) was long held to be the primary predictor of microbial activity in food systems. Recently, it was shown that different components present in food systems also influenced microbial growth and the minimum Aw at which microbial activity occurred. Thus, water activity alone is not a …
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Effect of antimicrobial agents on physical, chemical and microbiological characteristics of ready-to-eat bologna
… than 40C for up to 112 days of retail display. Water activity (aw), expressible moisture (WHC), pH, fat and moisture content, cooking yield, texture profile analysis, puncture test, Hunter color values, total aerobic plate count (PCA), yeast and mold count (YM), and lactobacilli count (MRS) were …
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Characterisation of natural radioactivity in Karoo Basin groundwater prior to shale gas exploration
… the need to obtain baseline data on natural radioactivity in Karoo groundwaters. The Karoo Basin groundwater radiological baseline developed through this study could serve as a reference to research potential future radiological contamination effects due to hydraulic fracturing. The major …
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Investigating the chemical basis of functionality differences between beet and cane sugar sources in model egg white foams and other products
… and cane meringue cookies, moisture content and water activity was obtained for unbaked meringues and meringue cookies. Additionally, texture profile analysis, three point break analysis, and differential scanning calorimetry was carried out on beet and cane meringue cookies. To gain insight into …
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Solute-Polymer States of Water and the Physico-Chemical Properties of Food Model Systems (Crystallinity, Sorption, Hysteresis, Starch)
… of solute-polymer mixtures as related to water binding, solute content and water activity (a(,w)). It was hypothesized that these properties were due to the presence of solute (SOL) and polymer (POL) water. The second objective was to develop a non-invasive analytical method for SOL and …
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Insights into the ecophysiology and biophysics of microbes involved in fermentation
… but glycerol was found to enhance metabolic activity and cell division at low water activity. Paradoxically, however, glycerol also exerted chaotropic activity when present at high concentrations and this ultimately limited the biotic activity of fungi, regardless of species, as …
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Evaluating post-harvest practices on the quality and safety of Kona coffee
… will reduce both the moisture content and the water activity (aw). Reducing aw below 0.75, especially in the first week of drying, is important for preventing or limiting mold growth. The purpose of this study was to 1) compare drying rates of Kona coffee bean batches using aw and moisture …
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Physicochemical properties of soy- and pea-based imitation sausage patties
… and textural properties, Hunter color, pH value, water activity and water holding capacity were considered to evaluate the contributions of the main ingredients. Altering the SPI or PPI level did not decrease the cooking yield; however, KOM did lower the yield. Lightness and yellowness of the …
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