KINETICS OF DRYING THE CRUSHED FRUITS TOMATO

Abstract

Intensive development of breeding work for the creation of new promising varieties of tomatoes and the introduction of modern technologies for their cultivation prompts the urgency of developing new resource-saving technologies for their processing for food purposes. These technologies, first of all, drying, allow to process the processing of large volumes of non-standard tomatoes, which at present do not find demand among consumers. In the conditions development of breeding and technological processes for the creation of new promising varieties tomatoes, the development and technological basis for processing their fruits into food products. Settlement of tomato fruit processing promotes the use in the food industry of non-standard fruits, which do not find the demand of the consumer and remain in the field. Progress in this direction is impossible without deepening scientific ideas about the dynamics and energy of dehydration of plant material. The aim of the work is to study the kinetic characteristics the drying of tomatoes to obtain competitive products. Materials and methods of research. The plum tomato fruits of Poplinsky type and hybrid Mikolka been grown in the subzone of inadequate moisture on the experimental sites the Institute Horticulture of NAAS (Borka village, Kyiv region). Where used the kinetics is drying has studied at the experimental booth of convective dryers in the Institute of Technical Thermophysics the National Academy of Sciences of Ukraine. For this purpose, the fruits of tomatoes were creamed cabbage, sliced in cubes of 5x5x5 mm and dried. Drying mode parameters: temperature of heat medium (air) t = 60°C, coolant velocity v = 2.5 m / s, moisture content d = 10 g / kg s.p, thickness of layer 15 mm. Research results. Plant tissues belong to colloidal capillary-porous bodies, which, depending on the type and conditions of vegetation, contain from 20 to 95% water. The kinetics of shredded fruits in the dryer shows the prospect of using convection drying, during 295 minutes. The obtained kinetic dependence shows the predominant influence of moisture content on the length process and has a correlation of 0.9701. It has been shown that the moisture content of the drying agent influences the intensity of drying rate at its initial stage. The value of the approximation of experimental data is 0.995. The drying process typically takes place in three stages and has a linear function in terms the coefficient of internal diffusion. The approximation of experimental data by a linear function shows a decrease in the level of transition moisture in the shredded particles of the fruit tomato to their surface and the value of the correlation connection is 0.7079. The kinetic equation for determining the critical moisture content in crushed tomato-cream fruit is presented. Conclusions. It is proved that convective drying of chopped tomatoes is one of the most promising ways of obtaining tomato products. The technological conditions of drying are studied and the optimum mode is determined: the size is 5x5x5 mm, the thickness of the layer is 15 mm, the temperature of heat medium (air) t = 60°C, the air velocity v = 2,5 m / s, the moisture content d = 10 g / kg s. etc., duration – 225 minutes. The kinematic coefficients according to graphical-analytical method were determined: a = 0.839, ln (α) = 1.3 and α (1 / c) = 0.262. It has been determined that the critical moisture content for crushing tomatoes is 1.503% / mm, and the process of combustion plant tissue begins there after.