An extruded foodstuff having a protein content in the range of 45% to 80% protein by mass and specific density of 0.10-0.40 g/cm.sup.3, including: a vegetable protein isolate which has been at least partly hydrolysed by enzymic hydrolysis, which provides the majority of the protein content and which has a relatively low level of low molecular weight peptides and which has a relatively low water imbibing capacity; up to 30% by mass of wheat gluten; up to 5% by mass of the foodstuff is sodium bicarbonate.