Physicochemical Changes of Cocoa Beans during Roasting Process

During cocoa beans roasting, there are physicochemical changes that develop the chocolate quality attributes. Roasting systems have a particular influence on the development of these characteristics, and the effects of operation variables for each system must be evaluated. The objective of this study was to evaluate the effect of roasting time and temperature in a rotatory system on cocoa beans physicochemical parameters of quality as moisture, water activity, pH, total acidity, color (L⁎,a⁎,b⁎), total phenolic content (TPC), and DPPH radical capacity. Cocoa beans were roasted as a function with a central rotatable design with 22 + 5 central points and 4 axial points (-1.414, -1, 0, +1, and +1,414) and a response surface methodology was applied. Temperature and time levels were 110–170°C and 5–65 minutes, respectively. The effect of the variables was nonlinear and modeled with a second-order response polynomial. Roasting time and temperature presented a significative effect (p<0.05) on the response variables except for both TPC and DPPH radical capacity in aqueous extract

Reproductive and morphological phenology of eight Mexican cacao clones (Theobroma cacao L.)

Objective: To describe the dynamics of floral biology and fruit development until physiological maturity, by performing a qualitative and quantitative characterization in eight Mexican cacao clones (Theobroma cacao L.), called: Caehui, Chak, Canek, Chibolon, Supremo, Tabscoob, K'in and Olmeca. Design/methodology/approach: In the phenological study, five trees were taken into account and five flower buds per tree were randomly identified (n=225). Twenty-one (21) qualitative and quantitative morphological descriptors were evaluated in fruits and grains. Descriptive statistics were established and a principal component analysis was applied to the quantitative descriptors. Results: The Chak clone presented the highest value for length and diameter of flowers buds in reproductive phenology, with 7.4 mm and 4.2 mm; the K ́in clone stood out in fruits, with 252 mm length; and Supremo in fruit diameter, with 102 mm. Significant differences were found in the morphological variables evaluated, in addition to significant positive correlation (p&lt;0.05 and p&lt;0.001) between most of the variables. The first two main components described 62.5% of the total variation. Findings/conclusions: The differences in measurements (length and diameter) of the flower buds are attributable to the genetic constitution; however, knowing the opening times allows us to have an exact reference in production levels. The parameters that contributed most to the variability observed were weight and diameter of the fruit, length and width of the grain, thickness of the exocarp, and weight of grains per pod

Evaluation of fermentative activity of lactic cultures for dehydrated yogurt with the use of different additives

Objective: To evaluate the fermentative activity of dehydrated lactic cultures with the use of various additives and vacuum drying, using yogurt as a model system. Design/methodology/approach: The yogurt was made with commercial lactic cultures (YF-L705 Yo-Flex CHR HANSEN) inoculated in whole milk incubated for 4 h/42°C. The yogurt was centrifuged at 6,000 rpm/15 min/4°C. The supernatant was removed, and the following additives were added to the precipitate: 1) SN, without additives, 2) Glycerol, 3) Calcium carbonate, 4) Yeast extract, 5) Glycerol and calcium carbonate, 6) Glycerol, calcium carbonate and yeast extract. The drying of 6 treatments was done up to 96h inside vacuum desiccators. Weight and moisture loss were recorded at 0, 24, 48, 72 and 96h. The dehydrated portions with the additives 1,2,3,4,5,6 was used as inoculums in milk for the production of yogurt; recording the drop in pH up to 24h and FTIR. As a control, non-dehydrated and lyophilized portion of yogurt were used. Results: The drying time at constant weight was 3 days. Dehydrated cultures containing yeast extract and calcium carbonate are associated with faster milk fermentation activity (p ≤ 0.05). Yoghurts manufactured with fresh cultures take 4 hours to ferment, dehydrated ones take over 12 hours. Infrared spectra show that yogurts produced with fresh or dried strains are of similar qualities. Study limitations/implications: The fermentative activity in dehydrated foods improves when alkalis are added, such as calcium carbonate, which is an antacid and releases CO2 upon contact with water and acid, stimulating anaerobiosis. Infrared spectra show that yogurts produced with fresh or dried strains are of similar qualities. Findings/conclusions: The best model to present the fermentation pH change curve is a Boltzman sigmoidal function. Yogurts with fresh or dried cultures differed in the time at which the milk is fermented. The fermentative activity in dehydrated foods improves when alkalis are added, such as calcium carbonate, which is an antacid and releases CO2 on contact with water, stimulating anaerobiosis. Infrared spectra show that yogurts produced with fresh or dried strains are of similar qualities.Objective: To evaluate the fermentative activity of dehydrated lactic cultures with the use of different additives and vacuum desiccation, using yogurt as model system. Design/methodology/approach: The yogurt was elaborated with commercial lactic cultures (YF-L705 Yo-Flex CHR HANSEN) and whole milk incubated at 42 °C for 4 h. Yogurt was centrifuged at 6,000 rpm/15 min/4 °C. The supernatant was eliminated and with the precipitate, 6 treatments were established by addition of additives: T1, Without additive, T2, Glycerol, T3, Calcium carbonate, T4, Yeast extract, T5, Glycerol, and T6, Glycerol, Calcium carbonate and Yeast extract; non-dehydrated and freeze-dried yogurt was used as control: T7 and T8, respectively. The precipitate of the treatments with additives was dehydrated in a silica gel in a desiccator and under vacuum conditions. The weight loss was recorded at 0, 24, 48, 72 and 96 h. The precipitate with dehydrated additives was used as milk inoculates for yogurt elaboration. The change of pH was recorded at 0, 1, 2, 3, 4, 5, 6, 7, 8 and 24 h. With the pH and the fermentation time, a model was established to present the change curve in fermentation pH and the Fourier transform infrared spectroscopy (FTIR). Results: The drying time to constant weight was 3 days. The fermentation pH change curve was a Boltzman sigmoidal function and analysis of variance was conducted with its parameters to assess the different fermentation speeds of the different treatments. The dehydrated cultures with Yeast Extract and Calcium Carbonate are associated with a higher fermentation activity of the milk (p &lt; 0.05). The yogurts manufactured with fresh cultures take 4 to 5 h to ferment and the dehydrated ones take more than 10 h. The infrared spectra showed that the quality of the yogurts produced with fresh or dry cultures are similar, which agrees with other studies. Limitations on study/implications: The dehydrated inoculated with the additives can be used to make yogurt with similar quality as to when inoculate with fresh culture is used, with the disadvantage of the fermentation time being longer. It is possible that this methodology can be used to dehydrate other inoculates based on lactic bacteria, but their effectiveness would have to be assessed experimentally. Findings/conclusions: This study shows an alternative method to dehydrate lactic bacteria in the laboratory with equipment of relatively easy access for any laborator

Functional Properties of Lupinus angustifolius

Protein isolates prepared by alkaline solubilization followed by isoelectric precipitation and freeze-drying from six varieties of Lupinus angustifolius (Haags Blaue, Sonate, Probor, Borlu, Boregine, and Boruta) grown in Mexico were evaluated for functional properties: nitrogen solubility, water-holding capacity (WHC), oil holding capacity (OHC), emulsion activity index (EAI), emulsion stability index (ESI), foaming capacity (FC), foam stability (FS), and gelling minimum concentration (GMC). The nitrogen solubility values, WHC, OHC, and FC did not show significant differences between the protein isolates. The solubility of the isolates was minimal at pH of 4.0 and 5.0 while the regions of maximum solubility were found at pH of 2.0 and 10.0. There were significant differences in EAI and ESI depending on the varieties used. The isolates of the Boregine and Borlu varieties showed the highest EAI with 29.3 and 28.3 m2 g−1, respectively, while the lowest index was recorded in the isolate obtained from the Sonate variety (24.6 m2 g−1). Like solubility, these indices also increased at both extremes of pH evaluated; both properties were minimal in the isoelectric pH range (4.0 to 5.0)

Microalgae Cultivation for Secondary Metabolite Production

Microalgae including cyanobacteria have been recognized as an excellent source of fine chemicals, renewable fuels, vitamins, and proteins and usually are found in health food stores around the world. However, the accumulation of these compounds generally occurs at end of the exponential growth phase; furthermore, biomass density in cultivation commonly is low. Open cultures have been used for pigment, biofuels, and biomass production, but these types of culture system are not a good choice for the production of fine chemicals, due to contamination problems and the expensive production costs. Closed photobioreactors can be operated in a continuous cultivation providing an increase on biomass density and contamination-free condition and generally working at a maximum growth rate under specific conditions; besides, these systems can recycle the consumed culture medium at least three times before a new enriched medium is supplied, generating a more cost-effective production system. In addition, microalgae metabolism can be manipulated to provoke a specific secondary metabolite accumulation by the addition of organic carbon source or changing light intensity or both. In other words, photobioreactors can operate in continuous mode, with efficient light supply and the supplementation of organic carbon source to produce fine biochemicals such as anticancer, antibacterial, antioxidant, lectins, antiviral compounds, and biofuels

Porous Silicates Modified with Zirconium Oxide and Sulfate Ions for Alcohol Dehydration Reactions

Porous silicates were synthesized by a nonhydrothermal method, using sodium silicate as a source of silica and cetyltrimethylammonium bromide as a template agent. Catalysts were characterized using thermogravimetric analysis, N2 physisorption, X-ray diffraction, FTIR spectroscopy, pyridine adsorption, potentiometric titration with n-butylamine, scanning electronic microscopy, and transmission electronic microscopy. The surface area of the materials synthesized was greater than 800 m2/g. The introduction of zirconium atoms within the porous silicates increased their acid strength from −42 to 115 mV, while the addition of sulfate ions raised this value to 470 mV. The catalytic activity for the dehydration of alcohols yields conversions of up to 70% for ethanol and 30% for methanol

Fertilidad edáfica y nutrición en el cultivo de cacao (Theobroma cacao L.) en tres suelos de Tabasco, México

El cacao es un cultivo tradicional en el sur de México, que exhibe baja productividad debido a limitantes edáficas y de nutrición, por lo que el objetivo de la investigación fue diagnosticar la fertilidad edáfica y contenido nutrimental de las plantaciones de cacao, en los principales grupos de suelos cultivados en la Chontalpa, principal zona productora de Tabasco, para identificar las variables del suelo y nutrimentales que restringen la productividad del cultivo. Mediante análisis de imágenes satelitales, se seleccionaron sitios de muestreos en suelos representativos del área de estudio y se geoposicionaron las coordenadas para ubicarlos. Se describieron perfiles de suelos para clasificar los suelos de los sitios de estudio, y se colectaron muestras de suelos a las profundidades de 0-10, 10-30 y 30-50 cm, para determinar variables indicadoras de la fertilidad del suelo. En árboles productores se colectaron muestras foliares para determinar las concentraciones de macronutrientes. Los resultados indican que las plantaciones se cultivan sobre Vertisols, Cambisols y Fluvisols, que no presentan restricciones en la mayoría de las propiedades edáficas. Sin embargo, debido a la baja relación C/N (< 12) de los suelos, hay una disminución en los contenidos de MO y N, que se suman a un déficit de K, que provocan bajas concentraciones de ambos macronutrientes en el follaje de las plantas. Se concluye que las principales restricciones edáficas que pueden afectar al cultivo del cacao en la Chontalpa son la rápida pérdida de MO y déficit de N y K en el suelo, que provocan bajas concentraciones de ambos nutrientes en el follaje de los árboles

Gestión del conocimiento: perspectiva multidisciplinaria. Volumen 11

El libro “Gestión del Conocimiento. Perspectiva Multidisciplinaria”, Volumen 11, de la Colección Unión Global, es resultado de investigaciones. Los capítulos del libro, son resultados de investigaciones desarrolladas por sus autores. El libro cuenta con el apoyo de los grupos de investigación: Universidad Sur del Lago “Jesús María Semprúm” (UNESUR), Zulia – Venezuela; Universidad Politécnica Territorial de Falcón Alonso Gamero (UPTAG), Falcón – Venezuela; Universidad Politécnica Territorial de Mérida Kleber Ramírez (UPTM), Mérida – Venezuela; Universidad Guanajuato (UG) - Campus Celaya - Salvatierra - Cuerpo Académico de Biodesarrollo y Bioeconomía en las Organizaciones y Políticas Públicas (C.A.B.B.O.P.P), Guanajuato – México; Centro de Altos Estudios de Venezuela (CEALEVE), Zulia – Venezuela, Centro Integral de Formación Educativa Especializada del Sur (CIFE - SUR) - Zulia - Venezuela, Centro de Investigaciones Internacionales SAS (CIN), Antioquia - Colombia.y diferentes grupos de investigación del ámbito nacional e internacional que hoy se unen para estrechar vínculos investigativos, para que sus aportes científicos formen parte de los libros que se publiquen en formatos digital e impreso

Gestión del conocimiento. Perspectiva multidisciplinaria. Volumen 17

El libro “Gestión del Conocimiento. Perspectiva Multidisciplinaria”, Volumen 17 de la Colección Unión Global, es resultado de investigaciones. Los capítulos del libro, son resultados de investigaciones desarrolladas por sus autores. El libro es una publicación internacional, seriada, continua, arbitrada, de acceso abierto a todas las áreas del conocimiento, orientada a contribuir con procesos de gestión del conocimiento científico, tecnológico y humanístico. Con esta colección, se aspira contribuir con el cultivo, la comprensión, la recopilación y la apropiación social del conocimiento en cuanto a patrimonio intangible de la humanidad, con el propósito de hacer aportes con la transformación de las relaciones socioculturales que sustentan la construcción social de los saberes y su reconocimiento como bien público

Gestión del conocimiento: perspectiva multidisciplinaria. Volumen 12

El libro “Gestión del Conocimiento. Perspectiva Multidisciplinaria”, Volumen 12, de la Colección Unión Global, es resultado de investigaciones. Los capítulos del libro, son resultados de investigaciones desarrolladas por sus autores. El libro cuenta con el apoyo de los grupos de investigación: Universidad Sur del Lago “Jesús María Semprúm” (UNESUR), Zulia – Venezuela; Universidad Politécnica Territorial de Falcón Alonso Gamero (UPTAG), Falcón – Venezuela; Universidad Politécnica Territorial de Mérida Kleber Ramírez (UPTM), Mérida – Venezuela; Universidad Guanajuato (UG) - Campus Celaya - Salvatierra - Cuerpo Académico de Biodesarrollo y Bioeconomía en las Organizaciones y Políticas Públicas (C.A.B.B.O.P.P), Guanajuato – México; Centro de Altos Estudios de Venezuela (CEALEVE), Zulia – Venezuela, Centro Integral de Formación Educativa Especializada del Sur (CIFE - SUR) - Zulia - Venezuela, Centro de Investigaciones Internacionales SAS (CIN), Antioquia - Colombia.y diferentes grupos de investigación del ámbito nacional e internacional que hoy se unen para estrechar vínculos investigativos, para que sus aportes científicos formen parte de los libros que se publiquen en formatos digital e impreso