Search

All water destined for human consumption must be subjected to disinfection processes via chlorination with the aim of eliminating the risk of the transmission of waterborne diseases. However, the treatment of water using this method leads to the formation of trihalomethanes (THMs), which are toxic compounds that may be ingested, inhaled, or absorbed by the skin, increasing the risk of carcinogenic and mutagenic processes. High trihalomethane concentrations in water may be directly related to physicochemical properties, such as temperature, pH, hardness, and potentially toxic metal concentrations. In this work, physicochemical characterization was performed and water quality was assessed with regard to the presence of trihalomethanes in 17 samples collected from points before and after storage in reservoirs. Atomic absorption spectroscopy to determine potentially toxic metals and the measurement of physicochemical properties demonstrated that all results were in accordance with the standards established by Brazilian legislation. Gas chromatography–mass spectrometry was used to determine levels of trihalomethanes in the water samples (trichloromethane, bromodichloromethane, chlorodibromomethane, and bromoform), which were also in accordance with the limits established by Brazilian legislation. Hierarchical clustering on principal components confirmed changes in the water quality depending on location. This work constitutes a paradigm for future studies on the monitoring of toxic organic compounds in water to avoid health problems in humans and animals. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the influence of storage (5°C) and abuse (15°C) temperatures and the addition of potassium sorbate (PS) on different quality attributes of modified atmosphere packaged (MAP) sliced Mozzarella cheese. It was observed that the temperature affected more significantly the cheese properties than the addition of PS in sliced MAP cheese. After 15 and 45 days of storage, the pH has decreased and the acidity has increased at 15°C. The instrumental color parameters were practically temperature and PS independent. Empirical equations that estimate the kinetics of change of the quality attributes in terms of the temperature, storage time, and PS were derived. Regarding the microbiological quality, the psychrotrophic bacterial population continued to grow during the storage independently on the treatment. Depending on the treatment adopted, LAB, yeasts and molds, and Escherichia coli population decreased during the period of 75 days of storage. Practical applications: The results obtained in the current study provide a quantitative evaluation of the influence of these independent variables on cheese quality. Empirical equations that estimate the rate of changes in the physicochemical and microbiological parameters were derived and can be used to evaluate the shelf life of sliced MAP Mozzarella cheese subjected to different storage conditions. Such information can help consumers and industry to optimize storage parameters of the product. [ABSTRACT FROM AUTHOR]

The study of alcohols solubility in different vegetable oils is important for industrial processes, such as, refining of oil, extraction of oil and biodiesel production. The experimental measurements were performed in a liquid-liquid equilibrium cell under constant temperature and stirring. The solubility of methanol, ethanol and isopropanol was investigated in refined oils of soybean, corn, sunflower and rapeseed. Methanol and ethanol solubility were analysed in the temperature range between 293.15 K and 333.15 K. Isopropanol solubility was analysed in the temperature range between 290.15 K and 296.15 K. It was observed an increase of solubility with the increase of temperature and with the increase of alcohol chain length. [ABSTRACT FROM AUTHOR]

The purpose of this work was to perform the oil extraction from the pulp of the variety Hass avocado by using the solvents methanol and ethanol in the temperature range between 283.15 K and 313.15 K and under atmospheric pressure. The extraction was conducted for a period of 10 hours with sampling at different extraction times. For both solvents it was observed an increase of oil extraction with the increase of temperature. Ethanol was the solvent which showed higher capacity to solubilize the oil. The experimental data were fitted to a model that considers the extraction based on two simultaneous processes. First, the oil present on the seed surface is quickly solubilesed by the solvent and second, the extraction of the remaining oil present inside the cells is governed by a diffusion process. [ABSTRACT FROM AUTHOR]

Copyright of Revista Acadêmica: Ciência Animal is the property of Revista Academica: Ciencia Animal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Acadêmica: Ciência Animal is the property of Revista Academica: Ciencia Animal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)