The Impact of Convection Drying Temperature on Content of Selected Phytochemicals in Dried Wild Garlic Leaves (Allium ursinum L.)

Abstract Wild garlic is a well-known and highly valued herbal plant. It is used fresh, unprocessed, and in the form of dried plants. The paper presents the results of the impact of the applied convection drying conditions at 30, 40 and 60°C on the parameters of the drying process as well as selected properties and composition of dried garlic obtained from wild garlic. It has been unequivocally shown that the increase in drying temperature significantly affects the content of thermally labile compounds, especially low-molecular weight antioxidants, including polyphenols and vitamin C. The analysis of the results clearly indicates that the dried plants obtained at 30°C contain relatively the highest amounts of antioxidant components and show the most volatile compounds profile similar to fresh wild garlic. However, the analysis of the parameters of drying process revealed that the temperature of the process significantly affects the time needed for the completion of drying process. The recommended of the most favourable process conditions should be based on an extended analysis and optimization of the entire process, taking into account not only the quality parameters of the dried material, but other parameters such as energy inputs and labour costs.