Shaping the Properties of Osmo-Dehydrated Strawberries in Fruit Juice Concentrates

Abstract

The growing interest in high-quality food leads to looking for new solutions in the production of natural fruit snacks. Osmotic dehydration is one of the processes, which can be used to obtain a minimally processed product as well as to give it specific characteristics. Usually, a sucrose solution is used as an osmotic agent; however, the use of chokeberry, strawberry, or cherry juice concentrates can be beneficial in the process of the osmotic dehydration of fruits. The process of the dehydration of strawberries with the use of fruit juice concentrates (chokeberry, strawberry, or cherry) and a sucrose solution as a standard was carried out at a temperature of 30 °C for 3 h. The kinetics of the processes (weight reduction, water loss, and solid gain) were evaluated as well as physical (water activity, color parameters L*, a*, b*, ΔE, texture with maximum force and compression work, and structure) and chemical properties (dry matter content, total polyphenols content, total anthocyanin content, vitamin C, antioxidant activity with DPPH and ABTS radicals, spectral analysis with FTIR method, sucrose, glucose and fructose content, and thermal decomposition with TG analysis). The use of fruit juice concentrates positively influences the enrichment of the final product with bioactive compounds, such as anthocyanin and vitamin C. Strawberry and chokeberry juice concentrates have proven to be good hypertonic media for increasing the antioxidant activity of dehydrated fruit. Moreover, the use of fruit concentrates has a positive effect on the sugar profile of dehydrated strawberries.

Keywords

• osmotic dehydration
• juice concentrates
• antioxidants
• structure
• chemical changes
• color