Aplicación de fibra y cáscara de coco para decolorar aceite de soja

The bleaching process is an important stage in the edible oil refining operation, and is carried out by using acid-activated bleaching earths. The aim of this study was to evaluate the efficiency of coconut fiber ash, shell ash, acid-activated fiber ash and acid-activated shell ash as compared to the commercial bleaching earth in the bleaching of neutralized soybean oil. Bleaching materials were added to neutralized oil at the concentration of 1% (w/v) with agitation under vacuum at 110 °C for 30 minutes. The values for red and yellow colors, carotenoids, chlorophylls, peroxide value, p-anisidine value, free fatty acid contents, copper and iron levels of the bleached samples were determined. The results indicated that all coconut-based adsorbents have been significantly more effective than commercial bleaching earth in reducing color and the greatest reductions in carotenoid (84.25%) and chlorophyll (82.30%) contents were obtained by using acid-activated fiber ash. The peroxide value for all treatments decreased. The amounts of iron and copper as peroxide compounds decreased considerably (44.59% and 23.53%) by using acid-activated fiber ash and acid-activated shell ash, respectively. Therefore, coconut fiber and shell as agricultural wastes which have been ignored in the past might be employed as effective agents to bleach crude oils, particularly soybean oil, in refining operations.El proceso de decoloración es una etapa importante en la operación de refinación de aceites comestibles que se lleva a cabo utilizando tierras decolorantes activadas con ácido. El objetivo de este estudio fue evaluar la eficiencia de las cenizas de fibra de coco, cenizas de cáscara, cenizas de fibra activada por ácido y cenizas de cáscara activada con ácido, en comparación con la tierra decolorante comercial, en la decoloración de aceite de soja neutralizado. Los materiales de decoloración se añadieron al aceite neutralizado a una concentración del 1 % (p/v) con agitación a vacío a 110 °C durante 30 minutos. Se determinaron los valores de colores rojo y amarillo, carotenoides, clorofilas, índice de peróxido, índice de p-anisidina, contenido de ácidos grasos libres, niveles de cobre y hierro de las muestras decoloradas. Los resultados indicaron que todos los adsorbentes a base de coco han sido significativamente más efectivos que la tierra decolorante comercial para reducir el color y la mayor reducción en los contenidos de carotenoide (84,25 %) y clorofila (82,30 %) se obtuvo mediante el uso de ceniza de fibra activada con ácido. El índice de peróxido en todos los tratamientos disminuyó. Las cantidades de hierro y cobre como compuestos peroxidantes disminuyeron considerablemente (44,59% y 23,53%) al usar ceniza de fibra activada por ácido y ceniza de cáscara activada por ácido, respectivamente. Por lo tanto, la fibra y la cáscara de coco como desechos agrícolas que se han ignorado en el pasado podrían emplearse como agentes efectivos para decolorar los aceites crudos, particularmente el aceite de soja en las operaciones de refinación

The effects of refining steps on kilka (Clupeonella delicatula) fish oil quality

Kilka fish are known as the main industrial and pelagic species of Iran that are captured abundantly in the southern Caspian Sea. This study was conducted to survey the effectiveness of refinement steps on Kilka (Clupeonella delicatula) crude oil quality and fatty acid profiles. Neutralization, bleaching, winterization and deodorization were performed on crude oil with deodorization done under two different conditions of A: at 180˚C for 120 min and B: at 140˚C for 240 min. During refinement, peroxide value (PV) significantly decreased from 7.66 meq/kg in crude oil to 0.5 in deodorized oil A and to 0.21 in deodorized oil B (p<0.05). Significant reduction in free fatty acids (FFA) was recorded from 0.86% oleic acid in crude oil to 0.15% in deodorized oil A and to 0.33% in deodorized oil B (p<0.05). N-3 fatty acids content and fatty acids composition were determined by GC-FID and n-3 fatty acids content increased from 18.74% in crude oil to 21.58% in deodorized oil A and to 21.75% in deodorized oil B. The red color in oil significantly decreased from 5.4 to 0.4 and 0.5 in deodorized oil A and deodorized oil B, respectively (p<0.05). Results confirm that refinement steps improved oil quality and raised n-3 PUFA concentration and n-3/n-6, properly. Deodorization at 180˚C for 120 minutes (A) was more effective than deodorization at 140˚C for 240 minutes (B) in removing off flavors

On partial order semantics for SAT/SMT-based symbolic encodings of weak memory concurrency

Concurrent systems are notoriously difficult to analyze, and technological advances such as weak memory architectures greatly compound this problem. This has renewed interest in partial order semantics as a theoretical foundation for formal verification techniques. Among these, symbolic techniques have been shown to be particularly effective at finding concurrency-related bugs because they can leverage highly optimized decision procedures such as SAT/SMT solvers. This paper gives new fundamental results on partial order semantics for SAT/SMT-based symbolic encodings of weak memory concurrency. In particular, we give the theoretical basis for a decision procedure that can handle a fragment of concurrent programs endowed with least fixed point operators. In addition, we show that a certain partial order semantics of relaxed sequential consistency is equivalent to the conjunction of three extensively studied weak memory axioms by Alglave et al. An important consequence of this equivalence is an asymptotically smaller symbolic encoding for bounded model checking which has only a quadratic number of partial order constraints compared to the state-of-the-art cubic-size encoding.Comment: 15 pages, 3 figure

Check Amount of heavy metals in muscle and fish oil Rutilus frisii kutum, Clupeonella cultriventris and Liza saliens

Heavy metal pollution in marine environments and the potential for bioaccumulation of contaminants have been considered as a serious threat for a long time. These contaminants accumulate in fish body and then transferred through the food chain to humans. The aim of this study was to determine the heavy metals cadmium, lead, arsenic, mercury and copper and iron metals in muscle and fish oil (Rutilus frisii kutum ،Clupeonella cultriventris ،Liza saliens). Three samples of Rutilus frisii kutum ،Clupeonella cultriventris and Liza saliens were caught in Mahmoud Abad area. One part of the muscle was dried by freeze drying method and another part was used to extract the oil. Then, using the atomic absorption spectrometric and Mercury Analyzer heavy metals concentrations were determined in muscle and fish oil. The results of muscle showed the highest accumulation of mercury (0.347±0.018), cadmium (0.08±0.001), copper (1.2156±0.059) and iron (2.643±0.231) in Rutilus frisii kutum and the highest level of lead (0.3593±0.015) and arsenic (0.0892±0.001) in Liza saliens. Moreover, in the fish oils samples, lead and mercury had the highest concentrations. The heavy metals in the samples were lower than or close to international standards. Therefore, their use does not pose a health problem for the consumers