Contenido de sesamol en sésamo, tahina, y halva por un nuevo método de análisis polarográfico y voltamétrico.

The contents of antioxidant lignans (Sesamol) in sesame, commercial formulations of tahina and halva, which are processed tahina foods, were determined by Differential Pulse Polarography (DPP) with a capillary hanging mercury drop electrode (HMDE). A platinum wire was used as the counter electrode and Ag/AgCl was the reference electrode. Samples have been analyzed by standard addition procedures and found to be quantitative (pSe determinó el contenido del lignano antioxidante (Sesamol) en sésamo, formulaciones comerciales de tahina y halva, que es el producto procesado de tahina, por polarografía de pulsos diferencial (DPP) con un capilar conteniendo un electrodo de gota de mercurio (HMDE). Un hilo de platino fué usado como el electrodo contador y Ag/AgCl como electrodo de referencia. Las muestras fueron analizadas por procedimientos de adición de patrones y se encontró que wl procedimiento era cuantitativo (p< 0.01). Debido a que el sesamol es un compuesto fenólico soluble en aceite, se estudiaron los porcentajes de aceite en sésamo, tahina y halva. Las muestras de sésamo contenían un 51.05-56.46 % de aceite mientras que las muestras de tahina tenían un 52.12 53.79 % de aceite. Se encontró que el porcentaje de aceite de halva fue un 28.79-30.13 % (p< 0.01). El sesamol encontrado en el sésamo fue de 0.26-0.32 mg/100 g de aceite, mientras que el sesamol en tahina fue de 10.98-12.33 mg/100 g de aceite. El sesamol de muestra de halva de procedencia comercial diferente varió entre 8.24-9.12 mg/100 g de aceite y 4.97 mg sesamol/100 g de aceite, respectivamente (R2= 0.9999) (p< 0.01). El método polarográfico propuesto (DPP) es un método rápido y reproducible para la determinación simultánea de lignanos fenólicos en sésamo y otros productos alimentarios que contienen sésamo. Éste proporciona una detección cuantitativa adecuada y sensible de este compuesto nutraceútico en alimentos comerciales

Detección de isómeros biológicamente activos del ácido linoleico conjugado en kaymak

Numerous physiological effects are attributed to conjugated linoleic acids (CLA). Biologically active isomers of CLA ( cis -9, trans -11 (C18:2) and trans- 10, cis- 12 (C18:2)) have been reported to have anticarcinogenic, antioxidative and antiatherosclerotic properties. Relatively rich sources of CLA include milk fat-containing foods such as kaymak. Kaymak is a kind of concentrated cream which is traditionally manufactured from buffalo or cow's milk mainly in Turkey . The objective of this study was to determine CLA concentrations during kaymak production. Kaymak was manufactured from cow's milk which was enriched with unfermented cream. Biologically active isomers of CLA in raw milk, cream and kaymak were analyzed using gas chromatography. The method was quick, repeatable and sensitive for the CLA determination of samples. Significant differences were found among the concentrations of both isomer and total CLA during the production process (pNumerosos efectos fisiológicos se atribuyen a los ácidos linoleico conjugados (CLA). Así los isómeros biológicamente activos ( cis -9, trans -11 (C18:2) y trans- 10, cis) del ácido linoleico han sido descritos con propiedades anticarcinogénicas, antioxidantes y antiarterioscleróticas. Fuentes relativamente ricas de CLA incluyen alimentos con grasas lácteas tales como el kaymak. El kaymak es una crema concentrada elaborada de leche de búfalo o vaca principalmente en Turquía. El objetivo de este estudio fue la determinación de la concentración de CLA durante la producción de kaymak. El kaymak objeto de estudio fue elaborado a partir de leche de vaca que fue enriquecida con crema no fermentada. Los isómeros biológicamente activos del CLA fueron analizados por cromatografía gaseosa en leche cruda, crema y kaymak. El método empleado fue rápido, reproducible y sensible. Se encontraron diferencias significativas en las concentraciones de ambos isómeros y de CLA total durante el proceso de producción (p < 0.01). Los contenidos totales de CLA para leche cruda, crema y kaymak fueron 0.08 ± 0.02, 0.234 ± 0.04 y 0.091 ± 0.08 g/100 g de lípido, respectivamente

Enhancement of the Phytochemical and Fibre Content of Beef-Patties with Himanthalia Elongata Seaweed

The effect of adding Himanthalia elongata seaweed (10 - 40% w/w) as a source of antioxidants and dietary fibre on physical, chemical, microbial and sensory traits of cooked beef patties was studied throughout chilled storage. Patties with seaweed showed reduced cooking losses and were nearly 50% more tender as compared to patties without seaweed. Microbiological counts and lipid oxidation were significantly lower in patties containing seaweed (P \u3c 0.05), by day 30 of storage there was no bacterial growth in samples with ≥ 20% seaweed and lipid oxidation levels were low (0.61 mg malondialdehyde/kg of sample). Seaweed incorporation significantly increased the dietary fibre (1.64 g per 100 g fw in 40% seaweed-patties), total phenolic content (up to 28.11 mg GAE/100 g fw) and DPPH radical scavenging activity (up to 52.32%) of patties compared to the control. Sensory analysis indicated that the seaweed-patties were accepted by consumers in terms of aroma, appearance, texture and taste. Patties containing 40% seaweed were rated highest in terms of overall acceptability, most likely due to improvement in texture and mouthfeel. Addition of seaweed in the formulation of beef patties leads to the enhancement of the nutritional and technological quality together with an acceptable sensory quality

Impact of dietary incorporation of Spirulina (Arthrospira platensis) and exogenous enzymes on broiler performance, carcass traits and meat quality

This study assessed the effect of Spirulina (Arthrospira platensis), individually and in combination with exogenous enzymes, on growth performance, carcass traits, and meat quality of broiler chickens. One hundred and twenty Ross 308 male chickens were allocated into 40 battery brooders, with 3 birds per cage, and fed ad libitum a corn-based diet during the first 21 D of the trial. The experimental period lasted from day 21 to 35, during which birds were fed 4 different diets: a corn-soybean basal diet, taken as the control group, a basal diet containing 15% Spirulina (MA), a basal diet containing 15% Spirulina plus 0.005% Rovabio Excel AP (MAR), and a basal diet containing 15% Spirulina plus 0.01% lysozyme (MAL). Body weight gain (P , 0.001) and feed conversion rate (P , 0.001) were improved in control chickens, when compared with those fed with Spirulina. In addition, Spirulina increased the length of duodenum plus jejunum in relation to the other treatment (P , 0.01). Chickens on the MAL diet showed a considerable increase in digesta viscosity (P , 0.05) compared with the control group. Breast and thigh meats from chickens fed with Spirulina, with or without the addition of exogenous enzymes, had higher values of yellowness (b*) (P , 0.001), total carotenoids (P , 0.001), and saturated fatty acids (P , 0.001), whereas n-3 polyunsaturated fatty acid (P , 0.01) and a-tocopherol (P , 0.001) decreased, when compared with the control. In conclusion, the incorporation of 15% Spirulina in broiler diets, individually or combined with exogenous enzymes, reduced birds’ performance through a higher digesta viscosity, which is likely associated with the gelation of microalga indigestible proteins. In addition, cell wall of Spirulina was successfully broken by the addition of lysozyme, but not by Rovabio Excel AP. Therefore, we anticipate that the combination of lysozyme with an exogenous specific peptidase could improve the digestibility of proteins from this microalga and avoid their detrimental gelationinfo:eu-repo/semantics/publishedVersio

Best practices in heterotrophic high-cell-density microalgal processes: achievements, potential and possible limitations

Microalgae of numerous heterotrophic genera (obligate or facultative) exhibit considerable metabolic versatility and flexibility but are currently underexploited in the biotechnological manufacturing of known plant-derived compounds, novel high-value biomolecules or enriched biomass. Highly efficient production of microalgal biomass without the need for light is now feasible in inexpensive, well-defined mineral medium, typically supplemented with glucose. Cell densities of more than 100 g l−1 cell dry weight have been achieved with Chlorella, Crypthecodinium and Galdieria species while controlling the addition of organic sources of carbon and energy in fedbatch mode. The ability of microalgae to adapt their metabolism to varying culture conditions provides opportunities to modify, control and thereby maximise the formation of targeted compounds with non-recombinant microalgae. This review outlines the critical aspects of cultivation technology and current best practices in the heterotrophic high-cell-density cultivation of microalgae. The primary topics include (1) the characteristics of microalgae that make them suitable for heterotrophic cultivation, (2) the appropriate chemical composition of mineral growth media, (3) the different strategies for fedbatch cultivations and (4) the principles behind the customisation of biomass composition. The review confirms that, although fundamental knowledge is now available, the development of efficient, economically feasible large-scale bioprocesses remains an obstacle to the commercialisation of this promising technology

JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY

The contents of potentially toxic elements lead and cadmium and the essential element copper in various milk and dairy products consumed in Turkey were determined by differential pulse polarography (DPP), primarily to assess whether the intakes comply with recommended desired concentrations for essential and permissible levels for toxic elements. A simple and rapid DPP method has been developed for the simultaneous determination of cadmium, lead, and copper in samples. Using the differential pulse mode, half-wave peak potentials as E-1/2 were -0.58, -0.40, and -0.07 V for cadmium (Cd), lead (Pb), and copper (Cu), respectively. Marketed formulations of dairy products have been analyzed by calibration and standard addition methods. Recovery experiments were found to be quantitative. The linear domain ranges were 0.00-674.28 mug/L for Cd (R-2 = 0.9999), 0.19-2.94 mg/L (p < 0.01) for Pb (R-2 = 0.9997), and 0.41 -133.46 mug/L for Cu (p < 0.01) (R-2 = 0.9999). The studies have shown that the method is a rapid, reproducible, and accurate determination of these elements in milk and dairy products and can be used in the analysis of marketed formulations in the milk and dairy industry