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The objective of this research was to investigate the influence of osmotic dehydration as a pre-treatment to the air drying of strawberries. Fresh, untreated strawberries were sliced and dried in a sucrose solution at a temperature of 50 oC and concentrations of 50 and 65 oBx. After osmotic dehydration, the slices were dried in a thin layer at air temperatures of 60, 70 and 80 oC, and an air velocity of 1 m/s. After osmotic dehydration, the moister content and solid gain at a sucrose solution concentration of 55 oBx were 3.44 gw/gdm and 0.062 gdm/g, respectively. However, the moister content and solid gain in at a sucrose solution concentration of 65 oBx were 4.08 gw/gdm and 0.0944 gdm/g (65 oBx), respectively. The effective moisture diffusivity of air drying varied from 1.57 x 10-9 to 4.43 x 10-10 m/s2, increasing with an increase in air temperatures and decreasing with an increase in pretreatment source concentrations. Lower air temperatures exert a positive influence on the rehydration time. A shorter air drying process positively affects the total changes in colour. The impact of pretreatment on colour changes in strawberries was not recorded after drying.

The aim of this paper is to present the influence of convective drying of organic pear pulp and adding ascorbic acid on changes in color, the difference in vitamin C content and also show the kinetics of convective drying. It was a two-factor experiment. The first factor was the air temperature needed for drying, between 45 °C and 65 °C, with a constant speed of drying air of 1.5 m/s; the second factor of the experiment was the adding of ascorbic acid to the pear pulp in the amount of 1 % and 2 % of the full mass of the prepared pulp. The lowest change in color was achieved by adding ascorbic acid in the amount of 2 % of the full mass of the pulp and drying air temperature of 45°C (ΔE= 23.981). The highest change was accomplished at the air temperature of 65 °C and by adding ascorbic acid in the amount of 1% (ΔE= 30.039). With samples where ascorbic acid was added reduction of vitamin C was over 99 % with all samples. By examining the kinetics of convective drying based on statistical indicators R, X2, RMSE, models Page and Logarithmic are the best in representing convective drying of pear pulp at air temperatures of od 65 °C and 45 °C respectively.

Aflatoxins (AFs), fumonisins (FUMs), zearalenone (ZEA) and deoxynivalenol (DON) have been recognized as major contaminants of maize. Therefore, the presence of AFs, ZEA, DON and FUMs was examined in a total of 100 maize samples from the Autonomous Province of Vojvodina. Sample analyses were performed using the Enzyme Linked Immunosorbent Assay method. The results obtained indicate that 74 % of the maize samples were contaminated with FUMs (540.1-5076 μg/kg), followed by 52 % contaminated with DON (275.2-882.1 μg/kg), 15 % contaminated with ZEA (35.6-183.5 μg/kg) and 5 % contaminated with AFs (2.28-4.31 μg/kg). Although 78 % of the samples were contaminated with at least one mycotoxin, the concentration of FUMs exceed the maximum level (ML) proscribed by the Serbian regulations only in 4 % of the samples. Furthermore, the detected concentrations of AFs, ZEA and DON were in accordance with national regulations. This study is the first research of its kind on the presence of AFs, ZEA, DON and FUMs in maize harvested in the APV in 2016.

The paper deals with the screening analyses of apple samples with the suspicion of having been treated beyond regular protection. The extraction of pesticides was carried out by the QuEChERS method. By GC-MSD and based on DRS analyses the presence of phosalone (tR=29.73 min) and dimethoate (tR=12.78 min) was detected. According to the National Regulation MRL value for the dimethoate in apples is 0.02 mg/kg and 0.01 mg/kg for phosalone. From the above facts it can be concluded that the dimethoate value was five times higher than allowed while that of phosalone was even ten times more.