Summary Stenocereus griseus pitaya has been evaluated as potential natural colourant on the basis of tristimulus colorimetry, differential colorimetry, and individual betalains, not previously conducted in conjunction with this raw material. Different technological treatment conditions were reproduced based on different pHs, temperatures and storage time. According to the results, cold temperatures (4 °C) maintained for longer the initial colour characteristics (L*, Cnormalab∗ and hab) of the extracts, whereas hab modifications began from the commencement of treatment at room temperature. Highly acidic extracts (pH 4) were the most stable samples in the light of the lower hab and Cnormalab∗ changes over time, even at room temperature. Betanin, isobetanin, betanidin and 2‐decarboxy‐neobetanin were more affected by temperature, whereas the content of the minor betalains significantly (P < 0.05) varied when pH was modified. Moreover, visually appreciable and quantitative colour changes (ΔEnormalab∗ > 3) were observed among all pH values and temperatures.