Determination of The Physical, Physio-Chemical and Chemical Properties of Gilaburu Fruits (Viburnum opulus) Dried by Convectional Drying Technique

Abstract

Our country has many species in fruit and vegetable cultivation. One of them is Gilaburu fruit (Viburnum Opulus), which has spread to different regions, especially in Kayseri. Longer preservation of products in fruits and vegetables; Drying process has been applied since ancient times to prevent deterioration caused by microbial and/or biochemical changes. One of them and the most common one is convectional drying in other words drying in a drying chamber under controlled hot air stream. In this study, Gilaburu fruits were obtained from a local producer in Kayseri. Drying processes were carried out in a convectional oven at 60, 70 and 80℃ in three repetitions. The effects of different drying conditions on the drying characteristics of Gilaburu fruits were examined. Drying time for Gilaburu fruits decreased with increasing temperature. As a color parameter total color change with respective to fresh fruit (ΔΕ) was investigated. The results indicated that it remained almost identical with temperature change. Similar trend was observed for rehydration rate. Titration acidity and pH values showed compatible changes. With temperature increase, titration acidity increased, as pH decreased. As textural properties, skin-hardness and elasticity of dried fruits were measured. As hardness increased, elasticity decreased with temperature elevation. Total phenolic content and antioxidant activity of dried samples were also examined. The results showed that there were increases in both of them with an increase in temperature.

Keywords

• convectional drying
• temperature change
• total phenolic
• antioxidant activity
• texture