KSZTAŁTOWANIE WŁAŚCIWOŚCI PRZEKĄSKI Z TOPINAMBURU HELIANTHUS TUBEROSUS L. WYTWARZANEJ METODAMI OSMOTYCZNEGO ODWADNIANIA I SUSZENIA

Abstract

Background. Growing consumer awareness of food consumption and expectations related to its quality and health of food in a daily diet, including for people with various health problems, point to the need to look for new directions in food production, such as dried Jerusalem artichoke snacks. The aim of the work was to examine the effect of osmotic dehydration and drying methods on the selected properties of dried Jerusalem artichoke. The research material comprised Jerusalem artichoke tubers. Fresh Jerusalem artichoke, initially dehydrated in an osmotic dehydration process in 60 % sucrose solution at 50 °C for 1 h, was dried by means of convection, microwave-convection, microwave-vacuum and freeze-drying. Results and conclusion. Freeze-dried samples, both with and without pre-treatment, reached the lowest value of water activity. At the same time, they were characterized by the highest content of dry matter. Compared to the raw material, the dehydration and drying of Jerusalem artichoke reduced the total polyphenol content and antioxidant activity. High values of both indices (176 ÷ 183 mg GAE/100 g d.m./ EC50 = 4.4 ÷ 4.6 mg d.m./cm3 ), slightly lower than in the raw material, were found in convective and microwave-vacuum dried samples. Using osmotic dehydration and selecting a method of drying Jerusalem artichoke allows to shape the properties of the obtained dried snacks with health-promoting properties. Microwave-vacuum drying proved to be particularly useful, mainly due to the short time of the process and the preservation of polyphenolic compounds and high antioxidant activity compared to freeze-dried products, considered to be a standard.