Generally, the product of pyrolysis of wheat stalk may be synthetic gases (H2, CO, CO2, H2, N2, Eethane etc) and liquid fuels (mostly aromatic hydrocarbons). Please see the color of fumes on combustion, if they are black then it means that you are dealing with aromatic hydrocarbons.
thank you Sir abdul majeed and Hassan usually in analytical fast pyrolysis of Lignocellulosic biomass, LG is more than 20% but in my experiment it is not more than 5%. while linear aldehydes are more in comparison with other study