Purple Sweet Potato Color, a pure natural and water soluble food color produced by our company, is extracted from purple root tuber of edible purple sweet potato (Impomoes batatas ) planted locally. The process is checking, washing, slicing, extracting, filtrating, purifying, concentrating, sterilizing(purple sweet potato color liquid), spraying & drying(purple sweet potato color powder). The main ingredient is cyanidin acyl glucoside & peomidin acyl glucoside.
Purple sweet potato color powder is red to purplish red, liquid is brown purple, both has the characteristic odor of sweet potato. It can be dissolved in water & alcohol, propylene glycol solution easily, but not in oil. The color of water solution changes when PH is different. When PH is between2-6 , the color is red or purplish red. The solution color becomes blue, and is unstable when PH is above 6. The color of solution can fade under light for a long time, and also has good resistance to high temperature in an acidic medium.Some nutritional benefits from sweet potatoes simply may not be achievable unless you use steaming or boiling as your cooking method. Recent studies show excellent preservation of sweet potato anthocyanins with steaming, and several studies comparing boiling to roasting have shown better blood sugar effects (including the achievement of a lower glycemic index, or GI value) with boiling.
The impact of steaming is particularly interesting, since only two minutes of steaming have been show to deactivate peroxidase enzymes that might otherwise be able to break down anthocyanins found in the sweet potato. In fact, with these peroxidase enzymes deactivated, natural anthocyanin extracts from sweet potato used for food coloring may be even more stable than the synthetic dye Red 40! This benefit isn't limited to the food's appearance since the anthocyanins have great health benefits as antioxidants and anti-inflammatory nutrients

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