Biodiesel, un combustible renovable

The substitution of traditional petroleum-based diesel fuel for others of biological nature, represents nowadays one of the greatest scientific challenges. Biodiesel is a renewable fuel derived from vegetable oils (edibles or non edibles; new or used) with similar properties to petroleum-based diesel fuel. Besides, it has significantly lower emissions of carbon monoxide, sulfur, aromatic hydrocarbons and particulate matter. The most common way to produce biodiesel is by transesterification of vegetable oils with methanol and homogeneous basic catalysis. A technological and economic assessment on the fundamentals of biodiesel production from vegetable oils, animal fats or used vegetable oils is presented in this work.La sustitución de los combustibles denominados fósiles o tradicionales, derivados del petróleo, por otros, de origen biológico, representa uno de los grandes retos que enfrenta la humanidad actualmente. Una de las alternativas más factibles para reemplazar el diesel de petróleo es la producción de biodiesel. É ste es un combustible renovable derivado de aceites vegetales (comestibles o no comestibles; nuevos o usados) y grasas animales que posee propiedades similares a las del petróleo. Además, se ha encontrado que con el uso de biodiesel se logran reducir las emisiones de monóxido de carbono, azufre, hidrocarburos aromáticos y partículas sólidas. La manera convencional de sintetizar biodiesel es mediante la transesterificación de aceites vegetales con metanol y catálisis homogénea básica. El presente trabajo describe los fundamentos de la producción de biodiesel sintetizado a partir de aceites vegetales, grasas animales o aceites de reúso, además del análisis de la factibilidad técnica y económica de la producción del mismo

Desarrollo de un método inmuno blot para detectar glucomacropéptido (GMP) como índice de adulteración de leche de vaca con suero de quesería

Milk is a product of high nutritional value and is considered commodity product for human consumption, which is why the dairy sector is of great socio-economic importance. Worldwidemilk processor industries and distributors have problems of milk adulteration with cheese whey. Most used method to detect cheese whey is the identification of a glycomacropeptide (GMP), which is present only in the cheese whey but not in milk. At present, methods to detect GMP require major work and time, presenting problems of sensitivity and accuracy at low concentrations. We developed a novel western blot analysis for GMP detection, using anti-GMP polyclonal antibodies. This assay can detect GMP with greater sensitivity, precision and speed that the methods used so far.La leche es un producto que contiene un alto valor nutricional y es considerada como un producto básico en la alimentación humana, razón por la cual, el sector lechero tiene gran importancia socioeconómica a nivel mundial. Las industrias procesadoras y comercializadoras de leche tienen problemas con su adulteración ocasionado por el suero de queserías. Uno de los métodos más usados para detectarlo es a través de la identificación de un glucomacropéptido (GMP), presente sólo en el suero de quesería y no en la leche. Los métodos para detectar GMP requieren de mucho trabajo y tiempo, y, a su vez, presentan problemas de sensibilidad y precisión en concentraciones bajas. En esta investigación se desarrolló un nuevo método de análisis mediante inmuno blot para la detección de GMP, usando anticuerpos policlonales anti-GMP. De este modo, puede detectarse GMP con una mayor sensibilidad, precisión y rapidez que con los métodos utilizados hasta ahora

Reactividade de anticuerpos policlonales anti-glicomacropéptido de suero de quesería bovino frente al glicomacropéptido de suero de quesería de oveja

The production and consumption of milk from sheep in Mexico and the world, is increasing every time because this has important advantages over cow�s milk. A common practice of milk producers is its adulteration with cheese whey. However, this affects milk processor industries because it decreases the yield of the products obtained. There are several methods for determining the presence of cheese whey based on the detection of a glycomacropeptide (GMP) that is present only in SQ and not in milk. However, none of these methods is focused on the detection of sheep�s GMP. In this study, polyclonal antibodies toward anti-glycomacropeptide bovine were used to determine the reactivity of these in front to the GMP of cheese whey from sheep as an indicator of the presence of cheese whey.La producción y consumo de leche de oveja en México y en el mundo cada vez se incrementa debido a que ésta tiene importantes ventajas frente a la leche de vaca. Una práctica común de los productores de leche es su adulteración con suero de quesería (SQ), lo que hace que tengan una mayor utilidad económica. Sin embargo, esto afecta a los industriales porque disminuye el rendimiento de los productos por obtener. Existen varios métodos para determinar la presencia de SQ basados en la detección de un glicomacropéptido que está presente sólo en SQ y no en la leche. Sin embargo, ninguno de estos métodos está enfocado a la detección del glicomacropéptido ovino. En este trabajo se utilizaron anticuerpos policlonales anti-glicomacropéptido bovino (anti-GMPb) para determinar la reactividad de éstos frente al glicomacropéptido ovino como indicador de la presencia de suero de quesería de oveja

Iron effect on the fermentative metabolism of Clostridium acetobutylicum ATCC 824 using cheese whey as substrate

Butanol is considered a superior liquid fuel that can replace gasoline in internal combustion engines. It is produced by acetone-butanol-ethanol (ABE) fermentation using various species of solventogenic clostridia. Performance of ABE fermentation process is severely limited mostly by high cost of substrate, substrate inhibition and low solvent tolerance; leading to low product concentrations, low productivity, low yield, and difficulty in controlling culture metabolism. In order to decrease the cost per substrate and exploit a waste generated by dairy industry, this study proposes using cheese whey as substrate for ABE fermentation. It was observed that the addition of an iron source was strictly necessary for the cheese whey to be a viable substrate because this metal is needed to produce ferredoxin, a key protein in the fermentative metabolism of Clostridium acetobutylicum serving as a temporary electron acceptor. Lack of iron in the cheese whey impedes ferredoxin synthesis and therefore, restricts pyruvate-ferredoxin oxidoreductase activity leading to the production of lactic acid instead of acetone, butanol and ethanol. Moreover, the addition of FeSO4 notably improved ABE production performance by increasing butanol content (7.13 ± 1.53 g/L) by 65% compared to that of FeCl3 (4.32 ± 0.94 g/L) under the same fermentation conditions

Effect of huitlacoche (Ustilago maydis DC Corda) paste addition on functional, chemical and textural properties of tortilla chips

AbstractThis study analyzed the addition of huitlacoche paste (HP) in baked tortilla chips (TC), evaluating its effects on functional, physicochemical and structural changes during processing. Two blue corn grains were nixtamalized, stone milled, air dried and milled to obtain flour; commercial blue corn flour (TM1) and commercial TC (TM2) were used as controls. Additions of 0, 3, 6 and 9% of HP were formulated; masas were prepared at 55% moisture content (MC), precooked and baked in an industrial machine. TC crispiness was influenced by grain characteristics and percentage of HP. Huitlacoche paste addition caused an increase in total dietary fiber (from 5.27 to 14.54%), total soluble phenolics content (from 17.52 to 37.60 mg GAE/100 g) and antioxidant capacity (from 6.74 to 7.98 μmol TE/g) in TC. Results suggest that tortilla chips added with huitlacoche can be an alternative to prepare this traditional edible fungus and produce healthier snacks, not fried and enriched with bioactive compounds