Utilization of red carrot roots (Daucus carota L.)‎ by-products as a source of natural pigments

Abstract EN

Nowadays growing demand for eco-friendly/non-toxic colorants, specifically for health sensitive applications such as coloration of food.

Recently, colors derived from natural sources for these applications have emerged as an important alternative to potentially harmful synthetic colors.

Natural color is one of the crucial factors for the consumers palatability of any processed foods.

The potential sources of coloring pigment anthocyanin is present in red carrot pomace material.

Extraction of these natural colors and using as alternative natural red colorants in jam is very important.

Chemical composition of red carrot pomace powder was determined.

Moisture, crude protein and ash content of dried red carrot pomace were 10.14, 4.86 and 5.89 %, respectively.

Meanwhile, it contained higher values of carbohydrates and crude fiber.

As for, minerals content it was observed that potassium and sodium content of red carrot pomace was found in larger amounts.

On the other hand, the total phenolic compounds and total flavonoids were 10.08 and 5.15 mg/g, respectively.

As well as, antioxidant activity was 86.48%.

HPLC separation indicated that there were two major anthocyanin components namely cyanidin 3-glucoside which represented to be 270.62 μg /ml, meanwhile the other one was delphinidin 46.39 μg /ml.

The effect of pH and temperature on anthocyanin stability was studied and the results indicated that its stability was more pronounced at acidic pH values (1.0 to 5.0), while, the highest degradation occurred at pH 7.

Moreover, the anthocyanin extract was more stable at temperatures 40 and 60°C after holding for 30 to 120 min.

Consequently, the holding of pigments at 80 and 100°C for 30 to 120 min.

caused reduction in the remaining of anthocyanin.

Concerning, the addition of anthocyanin extract with 1% was more palatable and recorded the highest sensory quality standards compared to other concentrations followed by the addition 0.5% of it.

It could be noticed that the effect of storage on color intensity of guava jam and the rate of decrement in color intensity were higher in samples stored at ambient temperature compared to same at 4°C.

Finally, it could be concluded that, red carrot pomace is considered as a very important good source of anthocyanin which recorded 130.54 mg/100g on dry weight basis.