Evaluation of methods for the quantification of ether extract contents in forage and cattle feces

ABSTRACT The objective of this study was to compare the estimates of ether extract (EE) contents obtained by the Randall method and by the high-temperature method of the American Oil Chemist's Society (AOCS; Am 5-04) in forages (n = 20) and cattle feces (n = 15). The EE contents were quantified by using the Randall extraction or AOCS method and XT4 filter bags or cartridges made of qualitative filter paper (80 g/m²) as containers for the samples. It was also evaluated the loss of particles, and concentration of residual chlorophyll after extraction and the recovery of protein and minerals in the material subjected to extraction. Significant interaction was observed between extraction method and material for EE contents. The EE estimates using the AOCS method were higher, mainly in forages. No loss of particles was observed with different containers. The chlorophyll contents in the residues of cattle feces were not affected by the extraction method; however, residual chlorophyll was lower using the AOCS method in forages. There was complete recovery of the protein and ash after extraction. The results suggest that AOCS method produces higher estimates of EE contents in forages and cattle feces, possibly by providing greater extraction of non-fatty EE.

Selection and role of a mix rosemary (Rosmarinus officinalis) - palmitate ascorbyl as antioxidant in a frying process / Selección y función de una mezcla de ascorbil palmitato-romero (Rosmarinus officinalis) como antioxidante en un proceso de fritura

Background: Several investigations report to rosemary as a plant rich in bioactive components with antioxidant potential, in this work, a rosemary extract was obtained that combined with ascorbyl palmitate provides a synergistic protection to a high fat diet (palm olein). Objectives: The objective of this study was to evaluate the effect of the addition of two extracts of rosemary (Rosmarinus officinalis): AP10R and AP30R at three concentrations of 1000, 1500 and 2000 ppm, on the oxidative stability of palm oil subjected to accelerated oxidation conditions and in a frying process. Methods: Lipid peroxidation of palm olein with and without antioxidants was monitored by measuring the concentration of hydroperoxides and total polar compounds; the thermal stability of the phenolic compounds in the oil was evaluated by fluorescence spectroscopy. Results: The AP10R extract at 2000 ppm inhibited olein oxidation by 30% and 60% in terms of total hydroperoxide and polar concentrations, respectively. The AP30 extract at 2000 ppm had similar inhibition behaviors with values of 27% of total hydroperoxides and 54% by total polar compounds in a time from 20 to 25 h. Conclusions: The results indicated that heating reduces the concentration of polyphenols; this decrease was more evident in olein without antioxidants, reflecting the effect of the polyphenols of rosemary extract on the thermal stability of palm olein.

Antecedentes: Diversas investigaciones reportan al romero como una planta rica en componentes bioactivos con potencial antioxidante, en este trabajo, se obtuvo un extracto de romero que combinado con ascorbil palmitato brinda una protección sinérgica a un sistema alimenticio con alto contenido graso (oleína de palma). Objetivos: El objetivo de este estudio fue evaluar el efecto de la adición de dos extractos de romero (Rosmarinus officinalis): AP10R y AP30R a tres concentraciones de 1000, 1500 y 2000 ppm, sobre la estabilidad oxidativa del aceite de palma sometido a condiciones de oxidación acelerada y en un proceso de fritura. Métodos: La peroxidación lipídica de la oleína de palma con y sin antioxidantes fue monitoreada midiendo la concentración de hidroperóxidos y los compuestos polares totales; la estabilidad térmica de los compuestos fenólicos en el aceite se evaluó por espectroscopia de fluorescencia. Resultados: El extracto AP10R a 2000 ppm inhibió la oxidación de oleína en 30% y 60% en términos de la concentración de hidroperóxidos y polares totales, respectivamente. El extracto AP30 a 2000 ppm tuvo comportamientos similares de inhibición con valores de 27% para hidroperóxidos y 54% para el contenido de fenoles totales en un tiempo de 20 a 25 h. Conclusiones: Los resultados indicaron que el calentamiento disminuye la concentración de polifenoles; esta disminución fue más evidente en la oleína sin antioxidantes, reflejando el efecto de los polifenoles del extracto de romero sobre la estabilidad térmica de la oleína de palma.

Rapid analysis of polar components in ophiocordyceps sinensis by conventional liquid chromatography system / 中草药·英文版

Objective: To develop a rapid high-performance liquid chromatography coupled with diode array detection (HPLC-DAD) method for the simultaneous determination of six polar compounds in Ophiocordyceps sinensis. Methods: A poroshell SB Aq column (50 mm × 4.6 mm, 2.7 μm) and gradient elution were used; The detection wavelength of compounds was set at 260 nm. The chromatographic peaks of the six investigated compounds in sample were identified by comparing their retention times with reference compounds. Results: All calibration curves showed good linearity (r > 0.999) within the tested ranges. The intra- and inter-day precisions of the six analytes were less than 0.8% and 2.1%, respectively, and the recoveries of the six analytes were between 95% and 103%. The validated method was successfully applied to the determination of six polar compounds in O. sinensis samples. Conclusion: The poroshell SB Aq column is suitable for the rapid analysis of polar components in Chinese materia medica on conventional HPLC system and the developed HPLC method is also helpful to the quality control of O. sinensis. © 2014 Tianjin Press of Chinese Herbal Medicines.

In-vitro antidermatophytic and preliminary phytochemical studies of petroleum ether and Inter-polar methanolic leaf extracts of Thevetia nerrifolia.

Antidermatophytic activity (Agar well diffusion technique) of petroleum ether and 98% methanolic leaf extracts of Thevetia nerrifolia (Apocynaceae) was evaluated against mycotic fungi namely, Trichophyton rubrum, Trichophyton tonsurans, Trichophyton mentagrophytes, Microsporum gypseum, dimorphic fungi such as, Candida albicans and pathogenic bacteria like, Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Brevibacillus spp. The significant antidermatophytic activity was shown by 98% methanolic extract, which inhibited all the test fungi and bacteria with time and dose dependent activity. The 98% methanolic extract retarded the growth of all the organisms at 40 mg/ml up to three weeks and beyond. The MIC’s, MFC’s and MBC’s were determined against all the test strains. Preliminary Phytochemical tests were carried out using both the crude extracts. This study provides basis for the isolation and purification of antidermatophytic inter polar compounds from the leaves of T. nerrifolia.

Contenido de compuestos polares totales en aceites de cocina previo uso más vendidos en Medellín (Colombia) / Content of total polar compounds in previously used cooking oils most marketed in Medellin (Colombia)

Antecedentes: la concentración de compuestos polares en un aceite es un indicador de deterioro térmico del mismo y de riesgo para la salud, con excepción de algunos aceites en los cuales el aumento de dichos compuesto está dado por la presencia de sustancias benéficas para la salud. Aunque no existe una norma internacional, las investigaciones reportan entre 0,5-3,0% de compuestos polares para aceites previo uso, que dependiendo del compuesto pueden tener efectos benéficos o adversos. Objetivo: determinar el contenido de compuestos polares totales en aceites uso previo de mayor comercialización en Medellín (Colombia). Materiales y método: se analizaron 14 marcas comerciales de aceite (oliva, canola, girasol y mezclas) y se determinó la cantidad de compuestos polares según metodología IUPAC 2000, con modificaciones. Resultados: el contenido de compuestos polares fue menor en los aceites de canola (1,22±1,70), seguido por los de girasol (1,96±3,30). Los aceites de oliva y las mezclas de aceite fueron los de mayor contenido (3,29±0,14 y 4,69±3,90 respectivamente). En siete muestras, el contenido de estos fue mayor al 3%, y correspondió a los aceites de oliva, las mezclas y una marca de girasol. No se encontraron diferencias significativas entre los promedios según tipo de aceite y marcas. Conclusiones: los diferentes tipos de aceites estudiados presentaron un porcentaje de compuestos polares dentro del rango reportado en la literatura.

Background: Concentration of polar compounds in cooking oils is an indicator of high temperatures damage and health risks. However, for some oils, the increase of those compounds is due to beneficial health substances. Although there is not an international standard, investigations report between 0,5-3,0% of polar compounds in previously used oil. Depending on the type of compound they may have beneficial or adverse effects. Objective: to determine total PC content in previously used cooking oils most marketed in Medellín (Colombia). Method and materials: 14 commercial brands of cooking oil were studied (olive, canola, sunflower and blended oils) and polar compound quantity was determined following IUPAC, 2000 methodology, with some modifications. Results: PC content was lower in canola oils (1,22±1,70), followed by sunflower oils (1,96±3,30). Olive and blended oils presented the highest content of PC (3,29±0,14 and 4,69±3,90 respectively). In 7 samples, PC content was higher than 3%. This percentage corresponded to olive, blended and one brand of sunflower oil. No significant differences were found among PC averages according to oil type and brand. Conclusion: the different types of cooking oil studied showed a percentage of CP within the range reported in the literature.

Avaliação da qualidade de óleos e gorduras de fritura em bares, restaurantes e lanchonetes / Assessment of used frying oils and fats in bars, restaurants and snack bars

Com o objetivo de avaliar a qualidade de óleos e/ou gorduras utilizados para fritura por imersão em bares, restaurantes e lanchonetes, foram coletadas 180 amostras de óleo e/ou gordura, sendo 90 antes e 90 após fritura. Aplicou-se um questionário para avaliar as técnicas de fritura e a infra estrutura dos estabelecimentos. Foram realizados os métodos analíticos para avaliar a alteração dos óleos e gorduras a saber, compostos polares totais (%), acidez (mgKOH/g) e índice de peróxido (mEq/kg). Das 90 amostras coletadas antes da fritura, 18,18 % demonstraram valores de compostos polares superiores ao limite estabelecido (5%), predominantemente nas amostras coletadas de lanchonetes. Quanto aos compostos polares totais, acidez e índice de peróxidos para óleos e gordura de fritura, 7,78%, 12,22 % e 2,22 % das amostras, respectivamente, apresentaram valores acima dos limites estabelecidos para efetuar o descarte. A avaliação das técnicas de fritura demonstrou dados insatisfatórios, tais como falta de controle da temperatura, tipo de óleo e equipamentos empregados. Os resultados obtidos indicam a necessidade de ações educativas no setor, assim como efetiva fiscalização por parte dos órgãos competentes.

Aiming at assessing the quality of oils and fats employed for frying food in bars, restaurants and snack bars, 180 samples were analyzed, from which 90 were collected before use and 90 after the frying process. A questionnaire was used in order to collect information on food frying procedures and on the respective food-serving places infrastructure. The analysis on alterations in oil and fat samples was performed by using the following analytical methods: total polar compounds (%), free fatty acid (mg KOH/g) and peroxide index (meq/kg). Among the 90 samples collectedbefore the frying procedure, 18.18% showed higher values of polar compounds over the established limit (5%), predominantly in samples collected from snack bars. In 7.78%, 12.22% and 2.22% of the analyzed frying oil and fat samples, the total polar compounds, free fatty acids and peroxide indices, respectively, were in a higher rate than those limit values established for discarding them. The inadequacy on the employed frying procedure was observed as this process was performed without control over the frying temperature, type of oil, and employed equipment.These findings indicate that the food-service locations require close surveillance supervisions.

Comportamento dos óleos de girassol, soja e milho em frituras de produto cárneo empanado pré-frito congelado / Sunflower, soybean and corn oils behavior in frozen pre-fried coated meat product frying

A utilização crescente de alimentos rápidos determinou a expansão de uma indústria de produtos fritos e pré-fritos. A compreensão das mudanças que o óleo sofre durante os processos de fritura é importante, pois pode levar à otimização destes processos, e a melhoria da qualidade do óleo de fritura e do produto final. Neste trabalho, objetivou-se determinar os níveis de alteração de diferentes óleos vegetais, girassol, soja e milho, no processo de fritura dos snacks produto cárneo empanado pré-frito congelado. As frituras foram conduzidas em temperatura de 180°C, relação superfície/volume (S/V) de 0,3 cm-1 e tempo total de aquecimento de 12 horas. Nos snacks procederam-se as análises de teor de umidade e lipídios; nos óleos as determinações de compostos polares totais, ácidos graxos livres e índice de peróxidos. Nenhuma análise apresentou alteração acima dos limites recomendados por alguns países. Desta forma, concluiu-se que as condições estabelecidas no processo de fritura são seguras, indicando que todos os óleos foram adequados à fritura, sendo o óleo de milho de maior estabilidade oxidativa.

The ever growing utilization of fast food determined the expansion of an industry of pre-fried and fried products. The understanding of the changes that the oil undergoes during the frying processes is outstanding because it may lead to the optimization of such processes as well as to improvements on the quality of both frying oil and the finished product. The purpose of the present study was to determine the alteration levels of different vegetable oils, sunflower, soybean and corn, in the frying process of snacks frozen pre-fried meat coated product. The frying sessions were carried out at 180ºC temperature, 0.3 cm-1surface/volume ratio and 12 hours overall heating time. As for the snacks, the moisture rate and lipids analyses were performed; for the oils, total polar compounds, free fatty acids and peroxide indices were determined. No analysis presented any alteration above the limits recommended by some countries. Therefore, it was concluded that the conditions established in the frying process are safe, suggesting that all of the oils were fit for the frying, being the corn oil the one of the highest oxidative stability.

Local Repeatedly-Used Deep Frying Oils Are Generally Safe

A review of the literature indicates that food scientists and health authorities in several countries, especially member countries of the European Union, are still very concerned about the potential health hazards of oxidized products and lipid polymers formed in repeatedly-used deep frying oils. During the frying process at temperatures of 170° – 200°C, steam formed from moisture in the food being fried help volatile products rise to the surface of the frying medium and into the kitchen atmosphere, imparting a mixture of fried-flavours and off-flavours. The non-volatile compounds formed, however, gradually build up in the oil as it is being repeatedly-used for food frying operations. These non-volatiles, primarily “polar compounds” (PC) and to a lesser extent lipid polymers, get absorbed into fried foods and eventually end up in our body system. Available local data suggests that deep-frying oil samples obtained from food hawkers and those produced under simulated deep-frying conditions in the laboratory, are generally safe as they contain PC within safe limits and rarely exceed the upper limit (UL) of 25%. This contrasts with the situation in some European countries where a very high proportion of frying oil samples collected from fast-food restaurants were reported to contain PC exceeding this UL. A p p r o p r i a t e l y, promotion of Hazard Analysis and Critical Control Points (HACCP) certification and gazetting of food regulations to limit the PC content in frying oils have been introduced in these countries to protect the health of consumers. Meanwhile, simple gadgets/test kits are available commercially to monitor the quality of the frying oil. This would greatly assist kitchen supervisors at restaurants and franchised friedfood outlets to know when best to change a batch of frying oil before the ULs of frying oil quality are breached.