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Aloe vera gel has nutritional and therapeutic properties due to presence of bioactive components. The aim of this study is to investigate the effect of pasteurization and storage time at different temperatures on some bioactive components of Aloe vera gel juice.

Aloe vera gel juice (Aloe barbadensis Miller) was pasteurized at 90°C for 1 min and stored up to 30 days at 4 and 25°C. The effect of pasteurization and storage time on glucomannan, vitamin C, DPPH inhibition (percent) and color of the juice was evaluated.

The results showed that pasteurization reduced vitamin C content and antioxidant activity 16% and 57%, respectively. During storage at 4 and 25°C, vitamin C and glucomannan contents reduced from 84.47 to 54.96 and 46.82 mg vitamin C/100 g dm and from 2.11 to 1.77 and 1.71 g/L, respectively. DPPH inhibition (percent) and Browning index (BI) increased significantly at both storage temperatures, which was more intensive at 25 than 4°C.

This paper is believed to be the only one which investigates the effect of thermal pasteurization and storage time at different temperatures on some bioactive components of Aloe vera gel juice.

The aim of the present research was to study and model drying of loquat fruit under vacuum conditions at three temperatures to select the best mathematical model for predicting drying rate of loquat during times which is used in designing of vacuum dryer. The dried product may be used in the preparation of soups, jam, premixed foods, snacks, etc.

Loquat samples were dried by vacuum oven (52 cm Hg) at three temperatures, 60, 70 and 80°C. First, moisture content was plotted against time for each treatment and after that moisture ratio curves were plotted. These curves were fitted with nine well-known models to select the best model.

Regression analysis of different models and values of RMSE and χ2 showed that page model had the best fitness due to highest R2 and lowest RMSE and χ2. Moisture diffusivity of loquat samples at 60, 70 and 80°C was calculated to be 6.87×10−10, 9.17×10−10 and 1.29×10−9 m2/s, respectively, which increased with temperature.

This paper is believed to be the only one which investigates and models drying loquat under vacuum conditions to select the best mathematical model for predicting drying rate of loquat.