Effect of the Application of a Coating Native Potato Starch/Nopal Mucilage/Pectin on Physicochemical and Physiological Properties during Storage of Fuerte and Hass Avocado (Persea americana).

The avocado fruit is an agro-industrial product with high export demand in Peru due to its sensory and nutritional qualities, which can be affected during storage. The study aimed to evaluate the effect of the application of a coating formulated with potato starch (Solanum tuberosum ssp andigena), nopal mucilage (Opuntia ficus indica), and pectin on the physicochemical and physiological properties during the storage of Fuerte and Hass avocados. Samples were taken in their harvest state from the plantation in "Occobamba", which is cultivated by the Avocado Producers Association in Chincheros, Apurímac, Peru. Physicochemical properties (titratable acidity, pH, total soluble solids) and physiological properties (weight loss, firmness, and color L* a* b*) were determined during 20 days of storage at 20 °C. The elaborated films present high transparency and low aw values. In the coated avocado of the Hass and Fuerte varieties, acidity and total soluble solids decreased significantly (p-value < 0.05) during the storage time. Weight loss and firmness of coated fruits decrease to a lesser extent. Luminosity L*, color index, and color variation showed better attributes for the coated samples. The use of coatings made with potato starch, nopal mucilage, and pectin allows the physicochemical and physiological properties of avocado fruits to be maintained for a longer time during storage.

Formulation of Novel Composite (Activated Nanoclay/Hydrocolloid of Nostoc sphaericum) and Its Application in the Removal of Heavy Metals from Wastewater.

The removal of heavy metals from wastewater is an environmental challenge which demands the use of environmentally friendly materials that promote a circular economy. This study aimed to apply a novel composite of an activated nanoclay/hydrocolloid in the removal of heavy metals from wastewater. A composite blended under pressure was prepared with spray-dried hydrocolloid derived from Nostoc sphaericum algae and activated nanoclay in an acid medium and 1M NaCl. The composite and components were analyzed through infrared (IR), X-ray (XR), ζ potential, cation exchange capacity (CEC), particle size, and SEM images. The composite was subjected to the adsorption of heavy metals (Pb, As, Zn, and Cd) at pH 4.5 and the removal percentage, kinetics, and adsorption isotherms were evaluated. It was observed that the activated nanoclay and the composite that presented a particle size of around 400 nm significantly increased (p-value < 0.05) the CEC, ζ potential, the functional groups, and chelating components, removing heavy metals above 99% for Pb, As 33%, Cd 15%, and Zn 10%. Adsorption kinetics was adjusted to the pseudo second-order model (R2 > 0.98), and the Langmuir and Freundlich models better represented the sorption isotherm at 20 °C. The formulated composite presents a good ability to remove heavy metals in wastewater.

Contaminación ambiental y gas natural de Camisea / Environmental pollution and the Camisea natural gas

Uno de las mayores preocupaciones para la ciudadanía del Cusco, en términos ambientales, es la reducción de emisiones de material particulado PM10 por procesos de combustión y por ello se ha planteado la sustitución de los combustibles actualmente utilizados por el Gas Natural como una alternativa de solución. En el presente trabajo se hace de una comparación de calidad energética, económica y de escenarios de emisiones con cada uno de los combustibles utilizados y recomendados para la actividad productiva. Para este efecto se utilizan factores de emisión, costo de generación de energía para cada combustible cobre el que se hace discusión. Se concluye que el Gas Natural es un combustible económico y más limpio que podrían beneficiar a la ciudad del Cusco en su empeño de reducción de emisiones de gases contaminantes emitidos hacia la atmósfera por procesos de combustión.

One of the greater preoccupations for the citizenship of the Cusco, in environmental terms, is the reduction of emissions of Particulate Matter (PM10) by combustion processes and for that reason the substitution of fuels at the moment used by the Natural Gas like a solution alternative has considered. In the present work one becomes of a comparison of power quality, economic and of scenes of emissions with each one of fuels used and recommended for the productive activity. For this effect emission factors are used, cost of generation of energy for each fuel on which the discussion becomes. One concludes that the Natural Gas is an economic fuel and cleaner than they could benefit to the city of the Cusco in its persistence of reduction of emitted polluting gas discharges towards the atmosphere by combustion processes.