A simple, rapid, diagnostic test developed for the detection of heat damage in bread wheat was shown to be suitable for a variety of durum wheat cultivars from New Zealand and Australia. This protein solubility test (PST) quantitatively measures the loss of solubility of albumins and globulins in heat-damaged wheat. The PST clearly distinguished sound from heat-damaged durum wheat that would cause problems in baking, seed germination, and dough-mixing and extrusion for pasta manufacture. In 1988, a New Zealand milling company used the PST to check lines of artificially dried durum wheat at the time of wheat delivery. No heat-damaged samples were found by the test or subsequently as a problem during the manufacture of pasta.