Pigment from red fermented rice as colouring agent for stirred skimmed milk yoghurts

Yoghurt is one of the most popular fermented milk products worldwide and is becoming more and more popular in China. In this study, the pigment of red fermented rice (RFR) by Monascus spp., which have been used as natural edible pigments in Asian countries for more than a thousand years, were applied to colour yoghurts. The colour stabilities, physicochemical characters and organoleptic qualities of the yoghurts containing 0 (control), 1.25, 2.5 and 5.0 pigment units/mL of milk, were measured after 1, 4, 7 and 14 days of storage at 4 °C. The results revealed that the colours of the yoghurts were stable during the storage period, and there was no significant effect (P > 0.05) of RFR pigment concentration tested on physicochemical properties and organoleptic characteristics of the yoghurts. This investigation demonstrates that RFR pigment could be used as a colourant in yoghurts.