Review of the Application of Stevia as a Natural Food Additive and Selection of Suitable Strawberry Cultivar for Strawberry Jam
Background : Currently, obesity and adult diseases as a result of sugar intake have been a consistent problem in Korea. Natural sweeteners as sugar substitutes have many advantages over sugar as a small quantity. Therefore, this study was conducted to investigate possibility of industrialization as food additives by using the nature sweetness components of stevia (Stevia rebaudiana Bertoni). Method and Results : Stevia was cultivated in a plastic house. The leaves and stems were harvested at October. They were ground into fine powder using a mill, and were extracted by high temperature and pression extraction method. The extracts were evaporated under vacuum and lyophilized. Three strawberry cultivars of ‘Seolhyang’, ‘Maehyang’, and ‘F22-196’ were cultivated in a plastic house and were harvested from March to May. The fruits harvested were stored at 50℃ until processing. In order to test the processing suitability of stevia extract, the characteristics of the three strawberry varieties (line) were investigated. As a result, the ‘F22-196’ line, which was bred as a processing strawberry, generally contained more antioxidant materials and activity than those of ‘Maehyang’ and ‘Seolhyang’ varieties. Comparing the sugar contents which affects the quality of strawberry jam, the average sugar contents of ‘F22-196’ line was higher than 'Maehyang' and 'Seolhyang' varieties. In the preparation of strawberry jam using ‘F22-196’, strawberry jam was prepared by adding only sugar or stevia extract powder, which was 1/100 of the amount of the sugar in only sugar strawberry jam, to the sensory test. As a result, we identified that sugar jam and stevia jam added stevia extract showed 50 : 50 at the sensory test and stevia jam does not make a difference to the marketing jam at the point of view of general consumers. Conclusion : ‘F22-196’ line represented the best quality for strawberry jam in test caltivars. Stevia powder is judged to be used as a sweetener of sugar substitutes in the production of strawberry jam and processing food.