Estudios computacionales de propiedades físico-químicas en análisis de calidad de aceites de maíz y maní

Oils are commonly used in cooking as a frying medium which has been constantly subjected to different levels of heating. In this work, we have considered the most commonly used oils namely peanut oil and corn oil. Quality analyses of corn and peanut oils were made by relating macroscopic properties (ultrasonic velocity, viscosity, and density) to microscopic parameters (intermolecular free length, adiabatic compressibility etc.,) by subjecting them to six cycles of heating (190 ˚C). Variation in the mentioned property indexes, the degree of degradation and reusability for the next heating cycle that could be used in the food industry and processing were monitored. Using Newton-Laplace and Wood’s equation, the adiabatic compressibility, acoustic impedance, and intermolecular free length of the oil were estimated from the experimental data. Ultrasonic velocity was observed linearly as related to viscosity with the dependency factor (R2 = 0.932). With the aid of experiential data, the physical thermodynamic parameters, particularly particle size, packing factor, chemical potential, and L-J potential were computed. A high correlation factor was observed by fitting ultrasonic velocity, viscosity, and density to Parthasarathy and Bakshi, and Rodenbush equations. In the study, ultrasonic velocity, a macroscopic parameter, could be decoded to determine the microscopic variations in oil subjected to different temperatures in an industrial application.Los aceites se utilizan comúnmente en la cocina como un medio para freír y se someten de forma continua a diferentes niveles de calentamiento. En este trabajo, hemos considerado dos de los aceites comunmente utilizados, como los de maní y maíz. Los análisis de calidad de los aceites de maíz y maní se han realizado relacionando propiedades macroscópicas (velocidad ultrasónica, viscosidad y densidad) con parámetros microscópicos (longitud libre intermolecular, compresibilidad adiabática, etc.) sometiéndolo a seis ciclos de calentamiento (190 ºC). La variación en las propiedades mencionadas indica el grado de degradación y su reutilización para el siguiente ciclo de calentamiento que podría ser lo usado en la industria y procesamiento de alimentos. Se utiliza la ecuación de Newton-Laplace y Wood, y a partir de los datos experimentales se estimaron la compresibilidad adiabática, la impedancia acústica y la longitud libre intermolecular de los aceites. La velocidad ultrasónica se observó estar linealmente relacionada con la viscosidad con el factor de dependencia (R2 = 0,932). Con la ayuda de los datos experimentales, se calcularon los parámetros termodinámicos físicos como el tamaño de partícula, factor de empaquetamiento, potencial químico y potencial L-J. Se observó un factor de correlación alto ajustando la velocidad, viscosidad y densidad ultrasónicas a las ecuaciones de Parthasarathy y Bakshi y Rodenbush. En el estudio, la velocidad ultrasónica, un parámetro macroscópico, podría decodificarse para determinar las variaciones microscópicas en el aceite sometido a diferentes temperaturas en una solicitud industrial

Modelling, characterization and quality analysis of heated oil using electric moment and chemical properties

The effect of temperature (30–90 °C) on the electrical parameter: dielectric constant (ε r ) of Sunflower, Olive and Corn oil exposed to three cycles of heating to frying temperature (175 ± 5 °C) was studied to exhibit the quality analysis of oil. Dielectric constant of heated oil was measured using designed inter-digitated electrode capacitor at different frequency (10 kHz–5 MHz) and temperature (30–90 °C). Dielectric constant (ε r ) of oil samples increases with cycles of heating. Variation of dielectric constant with frequency was premeditated using quadratic equation and the dependency factor was observed to be R 2 > 0.914. Chemical kinetic dielectric constant with temperature was studied using Arrhenius law and observed that activation energy increases with cycles of heating. Andrade’s equation was also fitted with the variation of ε r with temperature and the dependency factor (R 2 between 0.978 to 0.999) was observed to be highly correlated. Experiential physical properties like density, refractive index and ε r were significantly correlated with the pragmatic peroxide value. The observed relation between ε r with chemical property divulges the suitability of measured dielectric constant in real time and continuous evaluation of edible oil quality analysis in food industry

Ethanolic Noni ( Morinda citrifolia

Antioxidant and antimicrobial activities of ethanolic noni leaf extract (ENLE) without and with chlorophyll removal by sedimentation method were comparatively investigated. Total chlorophyll content was reduced by 82% in the top fraction (CR-ENLE) collected after 24 h at 4 °C as compared to that of ENLE. Antioxidant and antimicrobial activities were lower in the bottom fraction rich in chlorophyll (Chlo-ENLE) than others (P < 0.05). Based on the microbiological limit, the shelf-life of striped catfish slices pre-treated with 400 mg kg⁻¹ C-R-ENLE was extended to 9 days as compared to the 3 days recorded for the control (without pre-treatment). Slices treated with CR-ENLE had lower lipid oxidation than those treated with ENLE during refrigerated storage (P < 0.05). The sedimentation process was therefore a potential green method for producing ENLE having improved antioxidant and antimicrobial activities without green colour. It can be used as a natural additive for shelf-life extension of fish slices