Improving the hot air drying of garlic slices by perforation synergistic alcohol pretreatment

Long processing time represents a serious challenge in hot air drying since it led to high energy consumption and quality deterioration. A synergistic pretreatment of artificial perforation and alcohol maceration (PAT) was proposed in this study to improve hot air drying of garlic. Samples without pretreated, perforated, and subjected to alcohol pretreatments were used as control. The results showed that PAT pretreatment significantly reduced the drying time and energy consumed by 36.67%. Analysis showed that the mechanisms underlying the highest drying rate of PAT pretreated sample included pre-dehydration, capillary flow promotion and cell permeability enhancement. Samples pretreated with PAT exhibited the highest whiteness value, minimum shrinkage, lowest brittleness, and especially the highest content of volatile components, which is essential for its application as a spice. The antioxidant activity, total phenolics and allicin content were low in the PAT samples compared with other samples. This study provides a simple and effective approach to improve the drying of garlic.