An instant, plant-based version of golden milk

Researchers have developed a new method to make a plant-based, instant version of turmeric milk that maintains the beneficial properties of the ingredients while also extending its shelf life.

Golden milk, also called golden or turmeric latte, consists of milk, turmeric and spices, and is an option for people who want to avoid caffeine or coffee or maybe enjoy a unique flavour.

Anthony Suryamiharja, a graduate student at the University of Georgia who’s presenting the new research at the American Chemical Society (ACS) Fall 2024 meeting, said turmeric also features the bioactive compound curcumin — a polyphenol that has been studied for its potential anti-inflammatory and antioxidant effects.

“If we can incorporate bioactive compounds like curcumin into plant-based milks to bring them up to the same nutritional level as cow’s milk, why not?” Suryamiharja said.

Curcumin is difficult to separate from turmeric and requires the use of complicated extraction techniques, involving organic solvents, over multiple days consuming lots of energy. In addition, the compound tends to break down over time, shortening its shelf life. So, inspired by golden milk, Suryamiharja and colleagues wanted to investigate whether there was a way to extract and store curcumin within plant-based milk.

They first added turmeric powder to an alkaline solution, where the high pH made the curcumin more soluble and easier to extract than in plain water. This deep red solution was then added to a sample of soy milk, turning it a dark yellow colour. They brought it down to a neutral pH around 7. Just like low-pH acids, high-pH bases are not the most pleasant things to consume. The neutralised pseudo-golden milk could be enjoyed as is, but to further preserve it, the team removed the water from the solution through freeze-drying, producing an instant golden milk powder.

The method claims to extract curcumin from turmeric more efficiently than existing methods, while also encapsulating the curcumin in oil droplets within the soy milk. This means that when consumed, our bodies recognise the curcumin as fat and digest it as such, theoretically making the curcumin more bioavailable, or likely to be absorbed and able to have an effect in the body. Encapsulating the curcumin also protects it from air and water, preserving it and keeping it shelf-stable for longer.

While this work focused specifically on soy milk because of its high amino acid content, the researchers say that it could be applied to other plant-based milks, providing options for those with allergies to soy. In addition, their pH-driven extraction method could be used on different plant compounds with similar ease and efficiency. For example, blueberries are rich in anthocyanins, another water-soluble polyphenol. 

Though more research is needed before their instant golden milk appears on store shelves, the researchers believe the initial result is promising. The team hopes that this work can help explain the chemistry behind what may seem like nothing more than a simple beverage, as well as improve that drink’s nutritional value and convenience for those who enjoy it. As noted by Suryamiharja, “People usually do a lot of simple things in the kitchen, but they don’t really realise there’s a chemistry behind it. So, we’re trying to explain those unspoken things in a simple way.”

Click here to watch a video from the American Chemical Society on turmeric milk.

Image credit: iStock.com/ALEKSEI BEZRUKOV