Food Chemistry Advances (Jun 2024)
Determinant factors for berry derived anthocyanin persistency in stirred yoghurts
Abstract
The development of healthy and functional ingredients has been limited because of their low stability under given environmental and processing conditions, anyhow the use of anthocyanin as a natural food colorant has been recognized through the last decades. Therefore, the main objective of this study is stabilizing the natural colour of stirred yogurts fortified with berry fruit pulps during the entire shelf life of the product by evaluating the factors that affect the stability of anthocyanins. Initially the effect of time-temperature combinations applied in processing fruit pulps was analyzed through 6 different treatments; 85 °C for 1 second, 85 °C for 20 minutes, 90 °C for 2 seconds, 90 °C for 20 minutes, 95 °C for 2 seconds, and 95 °C for 20 minutes. Besides, varying sugar levels (0 %, 20 %, 40 %, 60 %) incorporated fruit pulps, and six yoghurt bases composed with different ratios of Skimmed Milk Powder (SMP), modified starch and gelatin were tested against the color stability of the stirred yoghurt fortified with berry fruit pulps. The color variations in the stirred yoghurts were evaluated in terms of “L, a, b” values represented by the colorimeter. There was a significant (p<0.05) effect of berry fruit pulp processing time and temperature on the colour of the stirred yogurt and processing berry fruits at 95 °C for 20 minutes was identified as the most appropriate treatment to get an optimum colour in stirred yoghurt. Further analysis with varying sugar levels and different yoghurt bases revealed that, both factors are potential determinants that exert a significant effect on the color stability in stirred yoghurts throughout the shelf life. Interestingly, the L color value was greatly affected with varying quantities of sugar and there was no considerable effect of SMP level on the color properties of the yoghurt. However, the modified starch level emphasized an increase in all the three-color properties. Conclusively, the relationship between these determinant factors and the anthocyanin biochemistry should be further studied to obtain the therapeutic as well as industrial advantage of anthocyanin.
