When cooked and subjectively colour scored, both short-term exposure to background substrate colour and increased dietary carotenoid levels improved cooked prawn colour (Table 4). As might be expected from the quantified results in the previous section, animals exposed to white substrates with no dietary carotenoid recorded the lowest colour grade scores (colour chart 6.9, salmofan 25.6). There was then a significant improvement in the colour of animals fed any level of carotenoidand exposed to white substrates (Table 4). Exposure to black substrates without dietary carotenoids produced an intermediate colour score (colour chart 8.9, salmofan 28.9), similar to that of the highest carotenoid diet exposed to white substrates treatment. The addition of carotenoids in the diet of animals exposed to black substrates produced a further significant improvement in colour grade score (Table 4). The highest colour grade score (colour chart 11, salmofan 32.6) was recorded in the animals fed 100 mg/kg Axn and exposed to black substrates