This work evaluated the texture, aroma and flavour quality of two Spanish commercial lamb categories: milk-fed lambs slaughtered at 10-12 kg live weight, and 'ternasco' lambs slaughtered at 20-24 kg live weight from two Spanish breeds, Lacha and Rasa Aragonesa. Texture was only affected by the breed effect in the mealiness parameter, with lamb from the Rasa Aragonesa breed perceived mealier than lamb from the Lacha breed. Texture quality was very influenced by the increase in live weight from 12 to 24 kg. The 'ternasco' lamb meat was found harder, mealier, more cohesive and more difficult to swallow than milk-fed lamb meat. Increased live weight developed woolly aroma, woolly flavour and more intense aftertaste in cooked lamb meat. Milk-fed lambs produced meat with a more characteristic aroma and flavour than 'ternasco' lambs. The increase of live weight from 12 to 24 kg had more influence on the lamb sensory quality than the breed factor.