A novel thermal pretreatment method called air frying improves the enzymatic saccharification effect of straw

Thermal pretreatment is a shared method to improve the efficiency of straw biochemical conversion. However, the process is often accompanied by problems such as the loss of carbon source. The objective of this study was to develop a novel thermal pretreatment method, called air frying, with less loss of biodegradable organic matter and favorable surface hydrophilicity. After pretreatment of two straws, the sugar yields were improved, and the improvement effect of corn stover was more significant. The total saccharification rate of corn stover increased from 31.31 ± 1.06% to 44.77 ± 1.23%, and the cellulose conversion rate increased from 44.10 ± 1.85% to 67.44 ± 2.37%. Functional groups with lower polarity on the surface were oxidized into the one with stronger polarity, so the hydrophilicity was enhanced. The surface roughness decreased, the surface tended to be flat, the original pores collapsed, and the average pore size increased, which was more conducive to the binding of enzyme and active site. The matching relationship between the optimal conditions and substrate, and the possibility of scaling up need further study.