Drying seedless Sultaniye grapes with oak wood ash solution

Due to the import of potassium carbonate (K2CO3) compound in the potash solution used in grape drying by conventional method; our country loses a significant amount of foreign currency. The aim of this study is to reveal the possibilities of using oak wood ash (MOK) which contains potassium intensively and can be used in alternative dipping solution to this compound. Analysis, the K+ content in pine wood ash does not meet our drying standards. As a first step, a mixture of 5%, 10%, 20%, 20%, 30%, 30%, 35% and 40% of oak wood ashes was obtained in 6 different ratios. Then, the process conditions in which the maximum amount of potassium passes into the solution were determined by using Taguchi Method. As a result of the analyses, it was decided that 10%, 20% and 30% MOK solutions were the most suitable solutions for drying process in terms of K+ content. The dipping solutions obtained from the filtrates obtained from the natural MOK mixtures, the dipping solution preparation sold in the market under the trade name Pusal and the potassium carbonate (potash) solution used in the conventional method were used in the drying process of sultaniye grapes and their effects on drying processes and grape quality characteristics were determined. It was concluded that oak wood ash (MOK) and Pusal, a commercial product, can be used as alternative grape drying reagents. Key Words: Oak Wood Ash, Raisins, Grape drying, Taguchi Method, Sultaniye Grape