Effect of Hot-Water Blanching Pretreatment on Drying Characteristics and Product Qualities for the Novel Integrated Freeze-Drying of Apple Slices

Figure 5

Vitamin C content of freeze-dried samples in 3 freeze-drying methods. VF-FD: apple samples without hot-water pretreatment were performed with vacuum freezing treatment and freeze-drying process; HWB-VF-FD: apple samples with hot-water pretreatment were performed with vacuum freezing treatment and freeze-drying process; HWB-PF-FD: apple samples with hot-water pretreatment were performed with plate freezing treatment and freeze-drying process. Note. Different letters on the same bar indicate significant differences at by Tukey’s HSD test.