Chemical, functional, and structural properties of spent coffee grounds and coffee silverskin

Spent coffee grounds (SCG) and coffee silverskin (CS) represent a great pollution hazard if discharged into the environment. Taking this fact into account, the purpose of this study was to evaluate the chemical composition, functional properties, and structural characteristics of these agro-industrial residues in order to identify the characteristics that allow their reutilization in industrial processes. According to the results, SCG and CS are both of lignocellulosic nature. Sugars polymerized to their cellulose and hemicellulose fractions correspond to 51.5 and 40.45 % w/w, respectively; however, the hemicellulose sugars and their composition significantly differ from one residue to another. SCG and CS particles differ in terms of morphology and crystallinity, but both materials have very low porosity and similar melting point. In terms of functional properties, SCG and CS present good water and oil holding capacities, emulsion activity and stability, and antioxidant potential, being therefore great candidates for use on food and pharmaceutical fields.The authors acknowledge the financial support of the Science and Technology Foundation of Portugal (FCT) through the grant SFRH/BD/80948/2011 and the Strategic Project PEst-OE/EQB/LA0023/2013. The authors also thank the Project "BioInd - Biotechnology and Bioengineering for improved Industrial and Agro-Food processes", REF. NORTE-07-0124-FEDER-000028 co-funded by the Programa Operacional Regional do Norte (ON.2-O Novo Norte), QREN, FEDER. Thanks are also given to Prof. Jose J.M. Orfao, from the Department of Chemical Engineering, Universidade do Porto (Portugal), for his assistance with the porosity analyses

Effect of different drying methods on the composition of steviol glycosides in Stevia rebaudiana Bertoni leaves

Drying techniques can modify the composition of certain plant compounds. Therefore, the aim of the study was to assess the effect of different drying methods on steviol glycosides in Stevia rebaudiana Bertoni leaves. Four different drying methods were applied to Stevia rebaudiana Bertoni leaves, which were then subjected to aqueous extraction. Radiation or convection drying was performed in stoves at 60ºC, whereas shade or sun drying methods were applied at 29.7ºC and 70% of relative humi- dity. Stevioside, rebaudioside A, rebaudioside B, rebaudioside C, rebaudioside D, dulcoside A, and steviolbioside were quantified by a validated HPLC method. Among steviol glycosides, the content (g 100 g-1 dry basis) of stevioside, rebaudioside A, rebaudioside B, and rebaudioside C varied according to the drying method. The total glycoside content was higher in sun-dried samples, with no significant differences compared to shade or convection drying, whereas radiation drying adversely affected the content of rebaudioside A and rebaudioside C (p <0.01) and was therefore a method lowering total glycoside content. The effect of the different drying methods was also reflected in the proportion of the sweetener profile. Convection drying could be suitable for modern food processing industries while shadow or sun drying may be a low-cost alternative for farmers

Lima Bean

According to the taxonomy, the bean belongs to the genus Phaseolus, which includes approximately 35 species of which 4 are cultivated: P. vulgaris L.; P. lunatus L.; P. coccineus L., and P. acutifolius L. (Arias-Restrepo et al. 2007). Phaseolus lunatus L. belongs to the Fabaceae family, and there are two domesticated genetic stocks from two different wild forms with two seed morphologies, small and large (Debouk 2019). The small seeds are known as ib., patashete and futuna (Yucatan, Chiapas, and Jalapa, Mexico, respectively), caballero bean (Cuba), ixtapacal (Guatemala), chilipuca (El Salvador), haba (Puerto Rico and Panama), sieva and comba (Colombia), and guaracaro (Venezuela), among others. The large seeds are known as lima, layo and pallar (Peru), torta (Colombia), palato (Bolivia), and manteotto (Argentina) (Debouk 2019). It is proposed that P. lunatus could have originated in the Neotropical region of America, ranging from Mexico to Chile, passing through the Andean region of Peru. It is believed that its origin is found in Guatemala since in this area the wild progenitor of this species was found; on the other hand, molecular studies propose that its origin is found in the Andean zone and that its distribution throughout the Americas was given by domestication (FAO 2018)

Detección de metales pesados y dicloro difenil tricloro etano (DDT) en músculos y órganos de bovinos en Yucatán

The purpose of this research was to determine copper (Cu), lead (Pb), cadmium (Cd), mercury (Hg), arsenic (As), dichlorodiphenyl-trichloroethane (DDT), and DDT metabolites, in the muscles and organs of cattle slaughtered in Mérida, Yucatan, Mexico, during 13 months. Pectoral muscle, kidney and liver were sampled in the Faculty of Veterinary Medicine and Animal Husbandry Processing Plant (RVet) (n=255), and in Mérida City Municipal Slaughter House (RMun) (n=225), from April 2001 to April 2002. Samples were analyzed using an atomic absorption spectrophotometer provided with hollow cathode lamps and an air-acetylene burner to determine Cu, Pb, and Cd, or by means of the use of cold vapor for Hg, or finally using a hydride generator for As. DDT and DDT metabolites were determined using a gas chromatographer with an electron capture detector. Results were analyzed calculating the general means and dispersion parameters as well as using the least square method to detect the effects of sample type, abattoir and season of the year, as well as all interactions. Cu content in 79 % of all the samples was higher than the limit recommended by Mexican Official Norms (MON¿s). The quantity was highest in liver samples. Cu levels were higher (P<0.05) in RVet during December to April. A great variability was found in Pb and most of the samples had a quantity higher that the one permitted by the MON¿s. Cd levels were lower than those allowed by the MON¿s. No Hg, As, DDT or DDT metabolites were found.El objetivo fue determinar cobre (Cu), plomo (Pb), cadmio (Cd), mercurio (Hg), arsénico (As), dicloro difenil tricloro etano (DDT) y sus metabolitos, en músculos y órganos de bovinos sacrificados en Mérida, Yucatán, México, durante trece meses. Se muestrearon músculo pectoral, riñón e hígado en el rastro de la Facultad de Medicina Veterinaria y Zootecnia (RVet) (n=255) y en el rastro Municipal de Mérida (RMun) (n=225), de abril de 2001 a abril de 2002. Se analizaron mediante espectrofotometría de absorción atómica, empleando lámparas de cátodo hueco y un quemador de aire-acetileno para determinar Cu, Pb y Cd, vapor frío (Hg) o mediante generación de hidruros (As). El DDT y sus metabolitos fueron determinados empleando un cromatógrafo de gases con un detector de captura de electrones. Los resultados se analizaron calculando su media general y parámetros de dispersión, así como por el método de mínimos cuadrados para detectar el efecto del tipo de muestra, del rastro, de la época del año, así como las interacciones. El contenido de Cu en el 79 % de las muestras fue mayor al límite permitido por la Norma Oficial Mexicana (NOM), destacándose el elevado contenido hepático. El contenido de Cu fue mayor en el RVet y durante diciembre a abril (P<0.05). El contenido de Pb presentó gran variación y un elevado porcentaje de las muestras estuvieron arriba de lo señalado en la NOM. El contenido de Cd fue menor a los límites permisibles en la NOM. No se encontró Hg, As, ni DDT y sus metabolitos

Rheological properties of aqueous dispersions of chia (Salvia hispanica L.) mucilage

The viscoelastic and flow behavior of aqueous dispersions with different concentrations of chia mucilage (Salvia hispanica L.) from Argentina seeds was characterized. The mucilage was obtained by two methods: (I) soaking-freezing-freeze drying-sieving, and (II) soaking-filtration-concentration-freezing-freeze drying. The effect of mucilage concentration, temperature, pH, ionic strength and presence of sucrose on the rheological properties of the aqueous dispersions with the addition of NaCl or CaCl2 was also evaluated. All the dispersion samples presented a shear-thinning behavior and a weak elastic gel-like structure because the storage modulus (G′) was larger than the loss modulus (G″) in the studied frequency range. The concentration of mucilage was the variable with the most significant effect on k (consistency index), whereas the presence of sucrose had the highest effect on n (flow behavior index) and tan δ. The type of salt and extraction method significantly affected k, not affecting n. Tan δ was affected mainly by the type of salt, and some interaction was observed between both factors. Method II and NaCl provided a higher consistency to the dispersions of chia mucilage. These results suggest that chia mucilage could be applied in the production of foods that require additives with thickening capacity, taking advantage of the zero calorific value of this hydrocolloid.Fil: Capitani, Marianela Ivana. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ingeniería Olavarría. Grupo Tecnologías de Semillas; Argentina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; ArgentinaFil: Corzo Rios, L. J.. Universidad Autónoma de Yucatán; México. Instituto Tecnologico Nacional; MéxicoFil: Chel Guerrero, L. A.. Universidad Autónoma de Yucatán; MéxicoFil: Betancur Ancona, D. A.. Universidad Autónoma de Yucatán; MéxicoFil: Nolasco, Susana Maria. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ingeniería Olavarría. Grupo Tecnologías de Semillas; ArgentinaFil: Tomás, Mabel Cristina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; Argentin

Characterization of Biodegradable Films Based on Salvia hispanica L. Protein and Mucilage

Biodegradable films of chia by-products (mucilage and protein-rich fraction (PF)) incorporated with clove essential oil (CEO) were obtained and characterized. The effects of polymer concentration (PC; 1.0–3.0 %, w/v) and CEO concentration (0.1–1.0 %, v/v) were evaluated as well as the pH (7–10), using a 23 factorial design with four central points. The films exhibited moisture values between 11.6 and 52.1 % (d.b.), which decreased (p < 0.05) with increasing PC and CEO. The thickness of the films increased (p < 0.05) with increasing PC. PC and pH influenced (p < 0.05) the lightness (L) and variation in color between red and green (a). The orientation of the color to yellow-blue hues (b) decreased significantly (p < 0.05) with increasing PC. Transparency was significantly lower and higher (p < 0.05) than PC and CEO, respectively. The film surface morphology was evaluated using atomic force miscrocope images, and thermogravimetric analysis (TGA) was performed to study the thermal stability of the films. The displacement and tensile strength were significantly lower (p < 0.05) at higher concentrations of CEO, this variable being the only one with a significant effect. The chemical composition of the films was confirmed utilizing Fourier transform infrared (FTIR) spectroscopy. The proportion of CEO added to the films had a significant influence on antimicrobial activity, inhibiting the growth of both Escherichia coli and Staphylococcus aureus.Fil: Capitani, Marianela Ivana. Universidad Nacional del Centro de la Provincia de Buenos Aires; Argentina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; ArgentinaFil: Matus Basto, A.. Universidad Autonoma de Yucatan; MéxicoFil: Ruiz Ruiz, J. C.. Instituto Tecnologico de Merida; MéxicoFil: Santiago García, J. L.. Centro de Investigación Científica de Yucatán; MéxicoFil: Betancur Ancona, D. A.. Universidad Autonoma de Yucatan; MéxicoFil: Nolasco, Susana Maria. Universidad Nacional del Centro de la Provincia de Buenos Aires; ArgentinaFil: Tomás, Mabel Cristina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; ArgentinaFil: Segura Campos, M. R.. Universidad Autonoma de Yucatan; Méxic