One of the thirty-nine melachot, “tzove’a – dyeing.” During the construction of the Mishkan, the artisans would dye the animal skins used in building this structure. Since the Mishkan’s construction serves as the basis for the Shabat prohibitions, it is forbidden to dye materials on Shabat.
The exception to this rule is food and beverages. The halachah states, “There is no ‘dyeing’ with regard to foods and there is no ‘dyeing’ with regard to beverages.” Therefore, it would be permissible to add a yellow spice to a food on Shabat, even though you are transforming the food’s color. Similarly, one can mix white wine with red wine, even though he changes the color of the white wine. In such cases, the prohibition of tzove’a does not apply, since it is food or liquid that is being “dyed.”
Does this halachah however apply in a case where one specifically intends to change the food’s color. In the cases described, the individual mixes the foods or liquids together in order to achieve the desired taste, such as the spice in his food or the mixing of the wines. Would the halachah be different if one specifically intends to change the color of a food or beverage?
Such a situation would arise on Friday night when there is a halachic preference to recite kidush specifically over red wine. If a person has only a very small amount of red wine, but enough white wine, he may want to pour the red wine into the white wine to make it red, so that he can recite kidush over the red wine, in accordance with the halachah. Is this permissible?
Rabbi Moshe Halevi (a”h), in his sefer, Menuchat Ahavah states that it would be forbidden to pour the red wine into the white wine with the specific intention to change the wine’s color.
He therefore advises that one pour the white wine into the small amount of red wine so that this will not change the color of the white wine. Ha’Rav Ovadyah Yosef, however, in his sefer, Chazon Ovadyah, maintains that the prohibition of “tzove’a” does not apply at all to foods and beverages, even in cases where one specifically intends to alter the color. In his opinion, it is permissible to pour red wine into white wine to change its color.
As such, it would be preferable in such a case to pour the white wine into the red wine and thereby satisfy all opinions.