Six cereals (wheat, barley, rye, triticale, millet, and wildrice) with moisture contents of 7−13% and six legumes (green pea, yellow pea, lentil, black bean, kidney bean, and pinto bean) with moisture contents of 8−10% were micronized to surface temperatures of 115 and 140 °C, respectively. Compared to nontreated grain/seed, micronized samples showed lower nitrogen solubilities in water at pH 6.0, 0.5 M NaCl, and 70% ethanol, indicating denaturation of albumins and globulins and, to a lesser extent, prolamins for some cereals such as barley and triticale. Results of extracting insoluble nitrogen with 0.5% sodium dodecyl sulfate and 0.6% 2-mercaptoethanol in borate buffer (pH 10) suggested that micronization induced hydrophobic aggregation in legume proteins and both hydrophobic and disulfide bonds in cereals. Increasing grain moisture content and micronization temperature progressively reduced nitrogen solubility in cereals and legumes. Keywords: Nitrogen solubility; protein; micronization; cereals; legumes