Food scientists have found a waste-free way to give cheddar cheese its consumer-pleasing orange color.
The new method creates no waste when squeezing out the watery whey, while preserving whey’s natural color for other commercial uses, according to a paper in the journal ACS Applied Materials and Interface.
“Observing cheddar cheese in the grocers’ dairy cases, you see different hues of orange and yellow, and they’re all very popular with consumers,” says Alireza Abbaspourrad, assistant professor of food chemistry and ingredient technology in the food science department at Cornell University.
The cheddar cheese’s hint of tint comes from the South America-grown red annatto seed. Adding the seed’s color to milk during the cheese-making process turns the mixture orange or deep yellow.
Currently, when the curds form, cheese processors are left with an orange color whey, the liquid part of milk, which is a valuable protein source. But as an additive to other foods, it’s not commercially viable because of its color.
“As whey drains, it still contains a lot of lactose, protein, and minerals, which can be a valuable additive when it is spray dried. Food companies can use the powder to add to food products, like infant formula or weight-training drinks, for example,” says Abbaspourrad. “But no one wants to use orange color whey.”
Abbaspourrad’s group has created an annatto-infused microcapsule—coated with a natural shell of casein, and a layer of fat—that when added to milk befriends the curd and leaves the liquid whey alone.
Inside the curd, microcapsules open during the cheese-aging process. As curds mature, enzymes that naturally dissolve and release reddish annatto (bixin) to color the curds degrade the fat layer. “There’s nothing artificial, it’s all natural, it’s all green,” says Abbaspourrad.
Assembling the microcapsules is a simple process. Imagine making a vinegar and olive oil salad dressing, and then vigorously shaking it—by way of a homogenizer—into an emulsion. The emulsion is then coated with fat and casein protein, which naturally sticks to the surface of droplets and becomes a group of microcapsules.
This system is quite pliant, says Abbaspourrad: “The microcapsule shell’s composition is controllable, tunable, and it can be optimized to use with other enzymes in other food systems or other media.”
Abbaspourrad and coauthor, doctoral student Raheleh Ravanfar, filed a provisional patent for the enzymatically-triggered microcapsules as a novel method to selectively deliver color to cheddar cheese and obtain white whey powder.
Dairy Management Inc. funded the study.
Source: Cornell University