With the anticipation of upcoming federal mandates to restrict artificial colorants in foods and beverages, product makers are moving forward with reformulations that replace artificial colors with natural ones. This first installment of our three-part series exploring how to apply natural colorants to dairy, bakery, and beverage products opens with dairy.

“Dairy is one of those tricky types of products when it comes to working with natural colors,” warns food scientist Abbey Thiel, PhD. Thiel explains that dairy products “experience multiple stress factor at once.” Milk, for example, undergoes multiple temperature changes, from 101.5°F/38.6°C in the cow, to chilled transport for processing, where it either undergoes further processing into any number of different items and conditions—many of which include a flash pasteurization step followed by rapid chilling. Milk and its subsequent products also are exposed to bright light from first expression, through processing, and in the dairy case, where they also endure a shelf life ranging from a couple weeks to even months. “If you have a color that’s not stable, that’s definitely going to show,” says Thiel, an expert in ingredient functionality and food innovation.

Milk starts out with a neutral pH, around 6 or 7. Many natural colors, such as anthocyanins or butterfly pea flower extract, only behave correctly under more acidic conditions. They provide rich reds or purples in low pH but in a dairy beverage they turn a muddy greyish-purple, brown, or dingy blue color, plus break down quickly. “The solution for dairy products is to find a pigment that doesn’t react or shift with pH,” advises Thiel. “Carotenoid-derived colorants work really well in these cases. Carotenes, lutein, lutein, lycopene—all of these will stay stable at a more neutral pH and really give like nice shades from a bright yellow to a deep strawberry red.”

Pasteurization or other UHT (ultra-high temperature) processing, as mentioned above, is usually mandatory for dairy. Again, Thiel recommends carotenoid-derived colorants such as lutein, carotenes, or lycopene. “These are fairly heat stable, especially if they’re in an emulsion.” She explains that they can be ideal for items such as strawberry milk, banana milk, mango yogurt, and similar colored fruit-flavored dairy products. “Heat stability is a major reason why you see these carotenoids colorants dominate dairy applications.” Such carotenoid-based food colorants are subject to oxidation, and Thiel stresses that it’s important to support them with antioxidants to keep fading under control.

Coloring Between the Lines: Dairy

As new federal rules push food and beverage makers away from artificial dyes, dairy developers are facing one of the toughest reformulation challenges yet.