Some properties of fruit juice produced by black raisins by traditional methods in Erbil region and changes during storage

Abstract

Grape (Vitis vinifera) is one of the most grown fruits in Iraq and is evaluated in different ways. This study aimed to determine some properties of the fruit juice that is traditionally produced from dried black grapes in the Erbil region and consumed directly, to make it durable by various methods, as well as to examine the changes that may occur during storage. For this purpose, some of the grape juices were pasteurized and the other part was stored using Na-benzoate in 500 ml glass bottles, at room temperature, under dark and light conditions for 6 months. In the stored products, pH, acidity, total dry matter, soluble dry matter, ash, color, total antioxidant (DPPH), Hydroxymethylfurfural (HMF) and browning reaction and total phenolic substance (folin-ciocalteu) analyzes as well as sensory evaluations were made periodically. As a result of the statistical evaluations, There is no difference between the applications in terms of color, but there is a slight decrease in the L value after the 4th month, depending on the storage period, while the pasteurized samples show higher values in terms of HMF and browning levels, the browning levels increase significantly in all samples after the 2nd month, and TFM values were decreased. It has been determined that all products are highly appreciated in terms of sensory properties, pasteurized samples are more appreciated, and the storage time does not have a significant effect on the sensory properties of the samples. In addition, it has been determined that beverages can be easily stored for a long time at room temperature with or without the addition of preservatives, only by pasteurization, and such a product will be in demand.