Caracterización fisicoquímica y organoléptica de una jalea de tres variedades de zapallo

The objective of the research was to determine the physicochemical and organoleptic characterization of jelly from three varieties of pumpkin: Cucurbita maxima, Cucurbita moschata and Cucurbita pepo. The study variables were pH (hydrogen ions), °Brix (%), viscosity (cP) and titratable acidity (%), which were analyzed through a Completely Random Design (DCA) proposing three treatments with four replicates. each. The results indicated that T2 (Cucurbita moschata) was the best treatment for pH (3.07), °Brix (65.75%) according to the provisions of the NTE INEN 415 standard, viscosity (9280.5cP) and acidity. titratable (1.12%) according to reports of other investigations of similar nature. Finally, the sensory analysis carried out through an affective acceptability test according to the attributes of color, flavor and texture indicated that the T2 (Cucurbita moschata) was the most accepted treatment by the tasters in all the attributes, thus, for the color attribute It presented an average acceptability of 4.40, in flavor of 4.68 and in texture 4.78.El objetivo de esta investigación fue determinar la caracterización fisicoquímicas y organolépticas de una jalea de tres variedades de zapallo:  Cucurbita maxima, Cucurbita moschata y Cucurbita pepo. Las variables dependientes fueron pH (iones de hidrógeno), °Brix (%), viscosidad (cP) y acidez titulable (%), las cuales se analizaron a través de un Diseño Completamente al azar (DCA) planteando tres tratamientos con cuatro réplicas cada uno. Los resultados indicaron que el T2 (Cucurbita moschata) fue el mejor tratamiento para pH (3,07), °Brix (65,75%) de acuerdo a lo establecido en la norma NTE INEN 415, viscosidad (9280,5cP) y acidez titulable (1,12%) de acuerdo a reportes de otras investigaciones de similares índoles. Finalmente, el análisis sensorial realizado mediante una prueba afectiva de aceptabilidad con una escala hedónica de cinco puntos, donde se evaluaron los atributos de color, sabor y textura señaló que el T2 (Cucurbita moschata) fue el tratamiento más aceptado por los catadores en todos los atributos, así, para el atributo color presentó una media de aceptabilidad de 4,40, en sabor de 4,68 y en textura 4,78

Aprovechamiento del Endocarpio del Plátano Verde (Musa Paradisiaca) parala Obtención de papel Ecologico.

The purpose is to obtain ecological paper from the endocarp of the green banana (Musa paradisiaca) as an alternative to reduce the environmental impact. An experimental design A x B (3x3) was applied where factor A represented the percentage of cellulose at 10%, 20% and 30% and factor B the recyclable paper cellulose at 10%, 20% and 30%, comprising 9 treatments with 3 replicates and a total of 27 experimental units. As raw material, the selected green plantain endocarp was used, which presented a humidity of 86.50%, a density of 0.93 ????/ ????????3 and a percentage of cellulose of 24.25. To make the pulp, the semi-chemical pulping method was used, this pulp was arranged in 27 racks and dried in the environment for 2 days and as a result, 27 sheets of 12 cm by 4 cm were obtained. The physical properties of the 27 paper samples obtained were experimentally analyzed, grammage, moisture and thickness were measured and compared with the respective TAPPI T standards (410, 411 and 412). These data were statistically evaluated using a Tukey test with 95% confidence in InfoStat. According to the results presented in this investigation, it is determined that the green peel used is not suitable for producing quality paper according to international regulations.El propósito es obtener papel ecológico a partir del endocarpio del plátano verde (Musa paradisiaca) como una alternativa para reducir el impacto ambiental. Se aplicó un diseño experimental A x B (3x3) donde el factor A representó el porcentaje de celulosa al 10%, 20% y 30% y el factor B la celulosa de papel reciclable al 10%, 20% y 30%, comprendiendo 9 tratamientos con 3 repeticiones y un total de 27 unidades experimentales. Como materia prima se utilizó el endocarpio de  plátano verde seleccionada la cuál presentó una  humedad de  86,50%, densidad de 0,93 ????/ ????????3 y un porcentaje de celulosa de 24,25. Para elaborar la pulpa se utilizó el método de pulpeo semi químico, esta pulpa se dispuso en 27 bastidores y se secó al ambiente por 2 días y como resultado se obtuvo 27 láminas de 12 cm por 4 cm. Se analizó experimentalmente las propiedades físicas de las 27 muestras de papel obtenido, se midió gramaje, humedad y espesor y se comparó con las normas TAPPI T respectivas (410,411 y 412). Estos datos se evaluaron estadísticamente mediante una prueba de Tukey con 95% de confianza en InfoStat. De acuerdo a los resultados presentados en esta investigación se determina que el  endocarpio de verde empleado no es apta para producir papel de calidad de acuerdo a las normativas internacionale

Evidence of human occupation in Mexico around the Last Glacial Maximum

The initial colonization of the Americas remains a highly debated topic1 , and the exact timing of the frst arrivals is unknown. The earliest archaeological record of Mexico—which holds a key geographical position in the Americas—is poorly known and understudied. Historically, the region has remained on the periphery of research focused on the frst Americanpopulations2 . However, recent investigations provide reliable evidence of a human presence in the northwest region of Mexico3,4 , the Chiapas Highlands5 , Central Mexico6 and the Caribbean coast7–9 during the Late Pleistocene and Early Holocene epochs. Here we present results of recent excavations at Chiquihuite Cave—a high-altitude site in central-northern Mexico—that corroborate previous fndings in the Americas10–17of cultural evidence that dates to the Last Glacial Maximum (26,500–19,000years ago)18, and which push back dates for human dispersal to the region possibly as early as 33,000–31,000years ago. The site yielded about 1,900stone artefacts within a 3-m-deep stratifed sequence, revealing a previously unknown lithic industry that underwent only minor changes over millennia. More than 50radiocarbon and luminescence dates provide chronological control, and genetic, palaeoenvironmental and chemical data document the changing environments in which the occupants lived. Our results provide new evidence for the antiquity of humans in the Americas, illustrate the cultural diversity of the earliest dispersal groups (which predate those of the Clovis culture) and open new directions of research

Evidence of human occupation in Mexico around the Last Glacial Maximum.

The initial colonization of the Americas remains a highly debated topic1, and the exact timing of the first arrivals is unknown. The earliest archaeological record of Mexico-which holds a key geographical position in the Americas-is poorly known and understudied. Historically, the region has remained on the periphery of research focused on the first American populations2. However, recent investigations provide reliable evidence of a human presence in the northwest region of Mexico3,4, the Chiapas Highlands5, Central Mexico6 and the Caribbean coast7-9 during the Late Pleistocene and Early Holocene epochs. Here we present results of recent excavations at Chiquihuite Cave-a high-altitude site in central-northern Mexico-that corroborate previous findings in the Americas10-17of cultural evidence that dates to the Last Glacial Maximum (26,500-19,000 years ago)18, and which push back dates for human dispersal to the region possibly as early as 33,000-31,000 years ago. The site yielded about 1,900 stone artefacts within a 3-m-deep stratified sequence, revealing a previously unknown lithic industry that underwent only minor changes over millennia. More than 50 radiocarbon and luminescence dates provide chronological control, and genetic, palaeoenvironmental and chemical data document the changing environments in which the occupants lived. Our results provide new evidence for the antiquity of humans in the Americas, illustrate the cultural diversity of the earliest dispersal groups (which predate those of the Clovis culture) and open new directions of research