The Influence of a Chocolate Coating on the State Diagrams and Thermal Behaviour of Freeze-Dried Strawberries

Chocolate-coated fruit is becoming more and more popular as a tasty snack. The subjects of the research were freeze-dried strawberries and dark and milk chocolate-coated freeze-dried strawberries. The DSC curves, sorption isotherms, and glass transition temperature were determined. The state diagrams of the freeze-dried strawberries and dark and milk chocolate-coated freeze-dried strawberries were investigated. The modulated differential scanning calorimetry (MDSC) technique was used to determine the glass transition temperature. The DSC diagrams of the studied samples showed differences in shape and course. The sorption isotherms of the freeze-dried strawberries and dark and milk chocolate-coated strawberries belonged to type II according to BET classification. A coating of milk or dark chocolate resulted in a significant reduction in the hygroscopic behaviour of the freeze-dried strawberries and could be considered a promising way to improve the shelf life of the product and improve the nutritional value for commercial production purposes.