Optimum procedure for production natural sweetener of concentrated mulberry extract by assessing the sensory and physicochemical properties

The berry tree is native to the dry climates such as Iran. Its fruit is juicy and rich in sugars, minerals and vitamins. Condensed mulberry extract has a lot of applications in various food industries as sweetener. The purpose of this study was to introduce a suitable method for production of high quality mulberry extract in order to prevent the loss of mulberries at the time of production peak and use the unique properties of berry fruit outside of the production season. In this project, three concentrating methods such as sunny, under conventional conditions and vacuum concentration were used to produce samples with desired brix of 65. Samples were packed in plastic pet bottles and kept in a lab environment away from sunlight for 3 months. Physicochemical experiments including pH, acidity, consistency, color, transparency and sensory properties such as flavor, aroma, concentration and total acceptance of samples were performed in two stages of 3 months and the results compared with each other. The results showed that the color factors L a b were more suitable in traditional samples. These factors decreased over time. The highest pH belonged to the industrial sample (4.84) and the lowest pH belonged to the sunny sample (4.61), and the pH of the samples decreased over time. The transparency of sunny sample (1.57) and industrial (0.804) were the highest and the lowest, respectively and transparency increased over time. In terms of sensory properties, the taste and aroma of traditional sample with scores (3) and (2.916) and the concentration of sunny sample with score (3.416) were the best samples. In conclusion, the traditional sample was selected, and the sunny sample was ranked second.