Have you ever wondered how to change the taste or color of fruit without genetic modification of plants, using only natural extracts and food processing capabilities? Or how to obtain different shapes, flavours and colours of dried apples? Pink apples flavored raspberry or strawberry, purple apples flavored chokeberry or blackberry? Such modifications and enrichment of fruit in healthy, valuable components, for example vitamins, is made possible by the process of osmotic dehydration.
– What does osmotic dehydration mean?
Osmosis is the movement of water in the direction that tends to equalize the concentration between the two environments (fruit and solution). The principle is quite simple: the fruits are thrown into solutions with a high concentration of osmotically active compounds (hypertonic solutions). Thereupon the osmotic pressure on the outside of the cell is increased and, as a result, water from the interior of the fruit is removed. At the same time the fruit is enriched with the required components. Various substances can be used for the preparation of such solutions, sugar being the most common one.
I try to find and use other substances, which are as effective as sugar and at the same time can be consumed by people, who for various reasons can not consume sugar. The effect of my work will be improved quality of life for people who have to give up eating dried fruit, mostly produced with the addition of sugar.
I want to create a product using innovative technology which is visually attractive and enriched with bioactive ingredients. My research experience is in osmotic dehydration of apples and strawberries in a variety of solutions. Fruit will undergo a dehydration process with osmotic solutions alternative to sucrose. Fruit dried this way should have low glycemic index and will be perfect for people with diabetes. The result of my research – a fruit snack – will have low sugar, but high fiber content. Thus, people suffering from abnormal sugar metabolism will be able to enjoy a healthy and tasty snack.
What makes my research innovative is the use, in the osmotic pre-treatment, of solutions which have hitherto not been commonly used in fruit processing. Techniques I use aim to reduce the energy intensity of the process, minimise water consumption and eliminate waste in the interest of sustainable economic development. The calculation is simple: part of the water is removed from fruit, the share of dry matter increases as a result and, consequently, drying time is shorter and more nutrients are preserved.
About the Author
Joanna Cichowska is a second year PhD student in the Faculty of Food Sciences. She is interested in phenomena occurring in food, in particular in fruit, which undergo mild processing. Her research is focused on osmotic dehydration of fruit and vegetables which is attractive from the point of view of sustainable economic development and the obtainment of new, attractive food products. She wants to create innovative snacks from fruits which can be healthier alternatives to sweets. She has gained experience through participation in the grant of the ERA-Net SUSFOOD. Currently, she is looking for an alternative to sucrose substances which can be used in the production of food for diabetics.