Description
The HI83742-27 is a high quality reagent that is pre-measured, allowing for users to achieve fast and accurate colorimetric measurements. This reagent allow for a direct reading of the sample. These reagents are designed to be used with samples that have an expected range of 0.00 to 15.00 for color density.
Analytical techniques have become a valuable tool of modern wine makers. Especially the definition and the processing techniques to obtain the desired wine color are of key importance. The right decisions taken during maturation of the grapes, processing, aging and blending, all strongly influence the final result of wine color. The color of wine is always read after removal of suspended matter. There are mainly two color components present, yellow and red but also a blue or green hue may appear. The color hue is the ratio between the yellow color concentrations over the red one, and is an indication about the degree of evolution. The yellow color in wine comes from the presence of tannins (polymers of flavonoid -procyanidins type, and non-flavonoid phenols) and can be read without dilution. The increase of the yellow-brown color in older wines is due to aging or oxidation. The red colors of wines are caused by free anthocyanins, co-pigments of anthocyanins, and polymerized phenolic compounds. The color of these pigments is pH dependent and can be intense dark. It is therefore necessary to dilute the wine sample taking care not to change the original wine pH. Hanna recommends using the special wine solvent to minimize possible errors due to dilution. Wine Solvent 3 is a stabilized and ready-to-use solution at a fixed pH value (=3.2) to compare different types of dark colored wine samples often used for blending.