Five-carbon sugars affect cooked meat flavor by the Maillard reaction. This research extends to the effects ofpH and cooking temperature on meaty and species flavor, sweetness, barnyard, and rancid flavor in sheep-meat. Glucose and xylose were each blended into ground longissimus meat to 0%, 0.5%, or 1% and heated to 75 degrees C. Xylose treatments browned more than glucose treatments, and xylose flavor effects were more marked. With xylose, sheepmeat flavor declined significantly, but meaty flavor also declined. Differences were marked between pH 5.93 and 6.52, but pH effects at lower pHs were more subtle. Sweetness increased in many treatments, suggesting that 75 degrees C did not fully exploit the Maillard reaction. Therefore, pressure-cooked casserole treatments, chilled and frozen, were used to study the effects ofxylose, packaging, and storage time on flavor. There were no flavor differences due to chill packaging (foil laminate compared with barrier bag) (not significant). Xylose addition reduced sheepmeat flavor by 24% on the 1 to 9 intensity scale (P<0.001), while meaty flavor and sweetness were unaffected. Rancid flavor was reduced by xylose addition (P<0.01), and the reduction in barnyard flavor approached significance (P=0.07). Chilled storage time to 29 d did not affect any attribute. In the frozen casserole trial (stored exposed to air), xylose had no significant flavor effects (all P > or = 0.38). However, storage to 71 d increased the rancid flavor score from a negligible 0.06 to 0.60 (P=0.04), suggesting that rancidity development swamped more subtle effects.