2.1.1. Materials

Lemongrass (*Cymbopogon citratus*) was purchased at Vuon Lai Market, District 12, Ho Chi Minh City, Vietnam. Harvested lemongrass was planted within 10 to 12 months. The initial moisture content of the material was 6.40 ± 0.15 (g water/g dry matter). Before drying, lemongrass was pre-treated

by washing and cut into uniformly sized samples with a length of 38.95 ± 1.35 cm and a thickness of 1.46 ± 0.14 mm (Figure 1). The moisture content was determined using the oven method [13].

**Figure 1.** The lemongrass material.
