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ResumenEl objetivo de este trabajo fue proponer un prototipo de medición de color y temperatura construido con los sensores DHT11 de temperatura y TCS230-3200 de color conectados a un Arduino Nano, con una conexión serial se transfirió la información a un ordenador con los programas PXL-DAQ y Microsoft Excel ® 2013, siendo las mediciones de color registradas en el modelo de color RGB para su conversión al sistema CIE L*a*b*. Un equipo de medición simultánea de color y temperatura a nivel piloto, como el que se propone, se convierte en una alternativa económica frente a los costosos equipos comerciales. Con el prototipo se analizó la pérdida de luminosidad y la variación temperatura del yacón (Smallanthus sonchifolius), y los cambios de índice de pardeamiento y diferencia de color. Estos mostraron un comportamiento similar al encontrado en la literatura.Palabras clave: Smallanthus sonchifolius; prototipo de medición; luminosidad; índice de pardeamiento; diferencia de color. AbstractThe objective of this work was to propose a color and temperature measurement prototype constructed with the temperature sensor DHT11 and the color sensor TCS230-3200 connected to an Arduino Nano, with a serial connection information was transferred to a computer with PXL-DAQ and Microsoft Excel® 2013 programs, the color measurements were recorded in RGB color model for a conversion to CIE L*a*b* system. A simultaneous color and temperature measurement equipment at pilot level, as the one proposed in this paper, becomes an economical alternative to costly commercial equipment. With the prototype the luminosity loss and changes of temperature of yacon (Smallanthus sonchifolius) were quantified, and the changes of browning indexes and color difference. These parameters presented a behavior similar to that found in the literature.

Mango cv. 'Tommy Atkins' is a highly appreciated fruit for its organoleptic characteristics and its resistance to minimal processing. However, some operations as peeling and cutting can generate microbial contamination and loss of bioactive compounds. Ultraviolet short wave (UV-C) is an alternative technology for fresh-cut products that leads to microbial inactivation and the increase of beneficial compounds. The effect of a UV-C dose of 6 kJ/m 2 was evaluated on quality attributes of fresh-cut 'Tommy Atkins' mango during days 0, 3, 6, 9, and 12 of storage (5°C, relative humidity: 85-90%), and compared with a positive control (conventional method by immersion in 10 mg/L sodium hypochlorite solution) and a negative control (without treatment). Physicochemical analysis (titratable acidity, pH, total soluble solid content, and firmness), superficial color evaluation, determinations of microbial counts, contents of total carotenoids, phenolics and flavonoids, and antioxidant capacity assays were performed. The results showed that UV-C treatment allowed to preserve microbial safety and superficial color of stored fresh-cut mango, and to increase the content of total carotenoids, which was 19.34 and 26.50 mg β-carotene/100 g fresh weight (FW) for control and UV-C treated sample at day 12 of storage, respectively. The DPPH • scavenging activity of the UV-C treated mango was also higher (0.60 mM TE/g FW) compared to control (0.27 mM TE/g FW) at the end of storage. However, UV-C treatment caused loss of firmness. Some native microorganisms of mango adapted to the stress caused by the treatments and the storage.

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Horticultural products disinfection with short wave ultraviolet light (UV-C) depends mainly on dose. This parameter is defined as the product between time and intensity radiation. In general, short doses cause beneficial or hormetic effects, such as decrease of microbial load and fruits and vegetables quality preservation. While UV-C light high doses or long exposure times generate changes in those products, such as enzymatic browning, loss of texture, among others, which cause a decrease in shelf life and functional properties. Therefore, this article presents the most cited techniques to determine doses in horticultural products, some experimental and others that employ microbiology and mathematical knowledge, radiochromic films and computational fluid dynamics (CFD). The review highlights that CFD allow the development of simulations in real environments, quickly and economically, including radiation models prone to experimental validation and help to improve the arrengement of horticultural products in the equipment to achieve a uniform irradiation.ABSTRACTLa desinfección de productos hortofrutícolas con luz ultravioleta de onda corta (UV-C) depende principalmente de la dosis. Este parámetro se define como el producto entre el tiempo e intensidad de radiación. En general, las dosis cortas ocasionan efectos benéficos u horméticos, tales como la disminución de carga microbiana y preservación de la calidad de las frutas y hortalizas durante su vida útil. Mientras que las dosis altas o los largos tiempos de exposición a la luz UV-C generan cambios en dichos productos, tales como el oscurecimiento enzimático, pérdida de textura, entre otros, los cuales provocan una disminución de la vida útil y la pérdida de las propiedades funcionales. Por lo tanto, este artículo presenta las técnicas más citadas para determinar las dosis en productos hortofrutícolas, algunas de carácter experimental y otras que emplean conocimientos de microbiología y matemáticas, películas radiocrómicas y la dinámica de fluidos computacional (CFD). La revisión destaca que la CFD permite el desarrollo de simulaciones en entornos reales de forma rápida y económica, comprende modelos de radiación que pueden ser validados de forma experimental y ayuda a mejorar la disposición de los productos hortofrutícolas en el equipo para lograr una irradiación más uniforme.