This study was conducted to fundamentally understand the relationship between biomass composition and key pyrolysis oxygenates that affect the quality of bio-oil. Unlike many studies where surrogates are used to probe the effect of biomass characteristics on pyrolysis; in this investigation, we used well-characterized biomass feedstocks with different natural varying levels of plant cell-wall components. With this approach, possible interaction effects of the biomass components which are not revealed in model studies are captured. Selected oxygenates from the pyrolysis of debarked sugar maple, poplar, willow, switchgrass, and hot-water extracted sugar maple were correlated with their composition (namely, glucan, xylan, arabinan, mannan, acetyl, lignin, extractives and ash). The pyrolysis was conducted at 550 degrees C using a bench scale pyroprobe-GC/MS and Pearson correlation coefficients were used to statistically analyze the data. Quantitatively, relationships between the biomass components and oxygenated species such as acetic acid, levoglucosan, hydroxyacetone, methyl pyruvate, furfural, 2-furanone, 5-hydroxymethyl furfural, 4-allyl-2,6-dimethoxyphenol, coniferyl alcohol, and 2-methoxy-4-vinylphenol were established. Statistically significant correlation between the acetyl content and acetic acid yield indicate that deacetylation of the lignocellulosic cell wall could help in reducing the acidity of bio-oils. Likewise, other strong correlations suggest that carbonyls could be reduced by lowering the hemicellulose fraction. The data also indicated possible interaction between lignin and polysaccharides on the formation of specific oxygenates. For example, it was found that feedstocks with high lignin content tend to produce high yields of hydroxyacetaldehyde. Similarly, feedstocks with high glucan fraction yield more phenolic aldehydes and ketones. Overall, it can be inferred from the results that both genomic science and pretreatment could be used as tools to modify the heterogeneity of lignocellulosics to reduce the complexity of biomass pyrolysis and improve prospects for producing better quality bio-oils. (C) 2014 Elsevier B.V. All rights reserved.