Some of the inferences that can be made from juice colours include the acidity or base of that particular juice.
lemon juice
the colour of lemons
Gold grape juice is orange.
I am able to observe the color of tomato juice (red) and the phase of tomato juice (liquid).
Cabbage juice is a natural pH indicator that changes color when mixed with acids or bases. When a base is added to cabbage juice, it typically turns a greenish-yellow color. This color change occurs because the pigments in the cabbage juice, known as anthocyanins, react to the pH change.
When lemon juice is added to grape juice, it typically turns a lighter shade, often appearing more pinkish or reddish. This color change occurs because lemon juice is acidic, which can alter the pH of the grape juice and affect the anthocyanins—pigments responsible for the color in grape juice. The shift in pH can lead to a more vibrant hue, depending on the specific grape juice used.
Apple juice is slightly acidic and therefore red litmus will not change color.
When you mix lemon juice with bromothymol blue (BTB) solution, the color will change from blue to yellow. This is because the acidity of the lemon juice causes the BTB indicator to shift to its yellow color.
pink
pink
The pineapple juice is acidic; the color with pH paper Merck no. 9565 is red to brown.
Universal indicators of colour juices include whether or not the juice is opaque or clear and the actual color of the juice.