International Journal of Pure and Applied Mathematics Volume 101 No. 2 2015, 281-288 ISSN: 1311-8080 (printed version); ISSN: 1314-3395 (on-line version) url: http://www.ijpam.eu doi: http://dx.doi.org/10.12732/ijpam.v101i2.12 P A ijpam.eu A FRUIT DRYING MATHEMATICAL MODEL A. Atykhanov 1 , D. Karaivanov 2 § , B. Kassymbayev 3 , D. Kolev 4 1,3 Kazakh National Agrarian University Almaty, KAZAKHSTAN 2,4 University of Chemical Technology and Metallurgy (UCTM) Sofia, BULGARIA Abstract: In this paper we assess the time of drying for any fruits under natural heat radiation. In order to assess the time period of drying process we use the method described in [1] being supplemented by an experimental technique. We show that the drying speed is a polynomial of third degree w.r.t. the quantity of the solid substance. This help us to estimate the time period of drying. AMS Subject Classification: drying process, evolution, differential equa- tion, time period assessment Key Words: 76N15, 80A20, 76Z99, 34A34, 34A12, 93A30 1. Introduction Drying technologies play a basic role in the food industry. Nowadays using of the solar energy in drying process gets more and more popular. The food drying is a physical process producing a very simple and at the same time useful effect. The drying is characterized by removing the water to a level that minimizes the deterioration phenomena due to microorganisms, enzymes or ferments [1], [3]- [6]. The drying process is very complicated of physical point of view. However, Received: November 23, 2014 c  2015 Academic Publications, Ltd. url: www.acadpubl.eu § Correspondence author