Alternative of Solar Drying in Agricultural Product Field.

A nowadays the drying methods do not exist at low cost that allow to store products with high humidity content as they are fruits and vegetables for great periods, without alteration of its nutritional, medicinal properties or even the organoleptic. Agribusiness is limited the use of the fresh product, preventing its development and innovation. The solar drying is an accessible alternative, nonpolluting and smooth, this is that the damages or changes in the nutritional, medicinal properties and quality of the product (texture, color, flavor) are minimum when is compared with others. To difference of the works reported, where the study takes generally at level laboratory with controlled factors, this work offer to contemplate a measure the natural climatic variables for example humidity, speed of wind and temperature during the drying process, as a contribution to the approach of the real application in field. The incidence of the solar radiation on the state of Guanajuato is around 1.200 W/m² average, besides the insolation of 9 hours daily and highest room temperature at the sun is 44 ^oC in the spring-summer season, attributes that to promote to the region by to use this natural resource in the agricultural product drying. The preliminary development of the work has been with prickly pear stems of the specie Opuntia ficus indica collect of extensive farming in the town of Urireo, Salvatierra, Gto. (Mexico). The flour´s quality obtained has been determined on the basis of color, activity of water and relation of dehydration. The sorption curves of drying product demonstrate lesser damage of the functional groups hydrated presents in their composition than it drying by oven. Also it was made the comparison on efficiency in time and costs of the drying by solar radiation and oven for prickly pear stems.