Based on 14 varieties maize samples collected by National Livestock and Poultry Breeding Data Center, the contents of starch, NSP, and nutritional components in grains of each maize cultivar were determined. The relationships among the components were examined using principal component analysis and simple correlation analysis.

Starch was the most important component in the grain, accounting for 70.97%~76.98% of the dry matter, followed by crude protein, which comprised 7.86%~10.34% of the dry matter, and NSP, which comprised 6.98%~9.76% of the dry matter. The NSP were predominantly composed of arabinoxylans and cellulose. The content of insoluble non-starch polysaccharides (INSP) was significantly higher than that of soluble non-starch polysaccharides (SNSP). The crude fat and crude ash contents in the grain were low and accounted for 3.55%~4.98% and 1.08%~1.49% of the dry matter, respectively. Significant negative correlations were observed between starch content and crude protein, crude fat, crude ash, total non-starch polysaccharides (TNSP), INSP, and insoluble arabinoxylans (IAX) contents (P < 0.05). The TNSP and INSP contents showed strongly significant positive correlations with cellulose content (P < 0.01). The INSP content showed significant positive correlations with crude ash, cellulose, and IAX contents (P < 0.05). The SNSP content was significantly positively correlated with β-glucan and cellulose contents (P < 0.05), and significantly negatively correlated with total arabinoxylans (TAX) and soluble arabinoxylans (SAX) (P < 0.05). The TAX and IAX contents showed a strongly significant positive correlation (P < 0.01). Crude protein, crude ash, TAX, and IAX contents were significantly negatively correlated with arabinose: xylose ratio (A/X) of TAX and A/X of IAX (P < 0.05). A highly significant positive correlation was observed between A/X of TAX and A/X of IAX (r = 0.99, P < 0.01).

Differences in the grain nutritional content were detected among the maize cultivars. Starch, crude protein, and NSP were the highest contributors to dry matter, and the predominant NSP components were arabinoxylans and cellulose. Correlations among certain nutritional components were observed, but further research on the relationship between them is needed.