I just opened a new unflavored and finished the old one. I noticed that the old one had a distinctly yellow color and the new one is distinctly more white.  What is the reason for this difference in color?  I'm concerned about the quality of the product.

Thank you for your message, and I'm sorry for any confusion in the different colors of our product!  We have had a few customers comment on the different colors that Promix may appear. The Promix formula always remains the same, and we use the same farms and the same 100% grass-fed cows.  The difference in color is purely based on the color of the cheese from which the whey is derived during the cheese making process.  Grass-fed milk naturally has a slight yellow color because of the extra beta carotene (plant based form of vitamin A, naturally yellow in color) found in the milk of grass-fed cows.  The dark yellow color in some batches of Promix like the ones in your previous order is from the natural annatto color used in making yellow cheeses (whey is produced from cheese making), whereas the whiter color is from the white cheese batches.  However, both colors have the same nutritional value in the final product and are made using our same standards for quality.  
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