Tag: Color change

Approximately 70-80% of a potato's dry matter is composed of starch, a storage carbohydrate that reacts distinctly with a specific solution. This high starch content is the reason that when performing an iodine test, the color of potato changes dramatically, providing a clear visual indicator of its composition.

A distinct purple or violet color is a key indicator of protein presence, according to tests such as the Biuret method. This color change is a cornerstone of biochemistry. It allows for the detection of proteins through a visible reaction. The characteristic color change results from copper ions reacting with proteins' peptide bonds.

When testing for glucose, the initial blue colour of Benedict's reagent changes to a range of colours, including green, yellow, orange, and brick-red, depending on the concentration of reducing sugar. This visual shift provides a semi-quantitative indication of the sugar level present in a solution.

According to scientific tests, plain alkaline water is naturally clear and colorless, just like neutral water. Therefore, the popular question, "Does alkaline water change color?", is based on a misconception derived from chemical reactions with special indicator agents.

According to scientific tests like the Biuret method, a solution containing protein will change to a violet or purple color when specific reagents are added. This distinctive color change is a reliable indicator for the presence of proteins, revealing the number of peptide bonds within the sample.

When a solution of iodine is dropped onto a cut potato, the initial yellowish-brown color of the iodine rapidly transforms into a deep blue-black or purple hue. This dramatic color change serves as a definitive indicator for the presence of starch, a complex carbohydrate abundant in potatoes and other plants.

In its crystalline form, astaxanthin exhibits a deep, glossy black-purple hue, which is a stark contrast to the vivid red-orange seen in many supplements. This dramatic difference raises the question: does astaxanthin change color under various conditions, and if so, how does this powerful antioxidant shift its appearance so significantly? The answer lies in the dynamic interplay of chemistry and biology.