# Shaping the Properties of Osmo-Dehydrated Strawberries in Fruit Juice Concentrates
## 3 Results and Discussion
### The Impact of Fruit Concentrates on the Chemical Properties
#### 3.3.2 The Impact of Fruit Concentrates on the Sugar Content in Osmotically Dehydrated Strawberries  
The fresh strawberries were characterized by the sucrose content at the level of 1.3 \(\pm\) 0.04 g/100 g d.m., glucose 29.5 \(\pm\) 1.81 g/100 g d.m., and fructose 33.8 \(\pm\) 1.51% g/100 g d.m. Figure 9 shows the content of individual sugars in osmotically dehydrated strawberries after 3 h. Based on these data, significant differences in sugar content as a result of the dehydration process were observed. As a result of the dehydration of strawberries with sucrose solution, the level of sucrose content increased to 36.7 \(\pm\) 1.6 g/100 g d.m. However, in the case of fruit juice concentrate solutions, the sucrose content was reduced compared with fresh strawberries. These observations may result from the leaching of sucrose from the strawberry tissue, in the case of fruit juice concentrates, resulting in its lower content. On the other hand, the increase in the sucrose content is caused by the  
Figure 8: Fourier transform infrared (FTIR) spectra of the solutions (**a**) and strawberries after osmotic dehydration (**b**) conducted in a different type of osmotic agent (sucrose and fruit concentrates). saturation of the raw material with a sucrose solution and, as a result, an increase in its content. A similar effect was observed by [PERSON] et al. in sour cherry dehydrated in an apple juice concentrate and a mixture of apple and cherry juice concentrates [15]. Strawberries osmotically dehydrated in strawberry and cherry juice concentrates were characterized by an increase in the content of glucose and fructose. Additionally, [PERSON] et al. [29] noticed a higher content of glucose and fructose in apple slices after osmotic dehydration in apple, grape, and cranberry juice concentrates. Furthermore, strawberries dehydrated in sucrose and chokeberry solutions recorded a decrease in these sugars. The fructose content was significantly higher in strawberries dehydrated in the strawberry juice concentrate solution. These differences can be explained by the different molar masses of the used osmotic solutions. Those with lower molar masses allow for an increased diffusion of the substance into the tissue of the raw material. The result is an increased sugar content [54]. Statistical analysis showed significant differences in glucose content between the strawberry dehydrated in the cherry juice concentrate solution and the other strawberry samples. Figure 10 shows the thermograms of fresh and osmotic dehydrated strawberries. The presented thermogravimetric curves show that the mass of the raw material decreased with the increase in temperature. All samples showed three phases of thermal decomposition. The first phase is from ambient temperature to 100 \({}^{\circ}\)C and is related to the evaporation of moisture [51]. In this stage, the total weight loss was from 3.1 to 4.4%. The second stage was recorded in the temperature range of 100-220 \({}^{\circ}\)C, where two small peaks were observed from 105-165 \({}^{\circ}\)C and 151-197 \({}^{\circ}\)C and a high peak was observed in the range of 170-212 \({}^{\circ}\)C [55]. The first two peaks are from fructose and glucose, while those degraded in the temperature range of 170-212 \({}^{\circ}\)C is sucrose. The mass loss was the highest for strawberries dehydrated in a sucrose solution. There was a noted mass loss from 28.6% for strawberries dehydrated in a chokeberry juice concentrate to 35.6% for material dehydrated in a sucrose solution. This is in agreement with the results presented in Figure 9. Next, the phase from 220-450 \({}^{\circ}\)C is observed, where the material is lost from 27.2 to 38% of its initial weight. In these temperatures, decomposition of the polysaccharides such as hemicellulose, cellulose, and lignin occurs [27]. The highest peak in this phase is observed for the chokeberry juice concentrate, where the mass loss was the highest and equal to 39.2%.