HERBS HIT THE SWEET SPOT TO EXTEND SHELF LIFE OF SUGARCANE JUICE

Lead researcher and University of South Australia PhD candidate Zarnab Asif says herbs could be the answer.

Sugarcane juice, one of the world’s most popular street-side refreshments, may soon last far longer in your fridge, and without the need for synthetic preservatives.

A team of food scientists from Australia and Pakistan has found that adding microwave-dried extracts of mint and coriander can extend the shelf life of sugarcane juice from three days to two weeks.

Their findings, published in Food Safety and Health, suggest a natural solution for one of the biggest challenges facing the global juice industry.

Widely consumed across Southeast Asia, Africa and Brazil, and increasingly popular in North America and Europe, sugarcane juice is loved for its natural sweetness and perceived health benefits.

But its short shelf life, thanks to its high sugar and water content, and rapid fermentation once exposed to air, has limited its appeal in packaged form.

Traditionally, producers have relied on synthetic preservatives to slow spoilage, but these additives are falling out of favour due to their potential health risks.

Lead researcher and University of South Australia PhD candidate Zarnab Asif says herbs could be the answer.

“Not only are they natural antioxidants; they also extend the shelf life of sugarcane juice for up to a fortnight.

This has huge implications for the global juice industry, particularly in tropical regions where sugarcane juice is often produced and sold fresh on the street,” Asif says.

The research team compared conventional methanol extraction with a new microwave-assisted drying method.

By heating the leaves with microwaves, antioxidants such as polyphenols, flavonoids and vitamin C are released more efficiently while protecting heat-sensitive compounds.

Co-author Dr Tayyaba Alvi, from Green International University in Lahore, says the results were striking.

“The microwave-derived mint extracts displayed antioxidant activity of 74%, higher than both methanol extracts and fresh leaves. Coriander extracts also performed strongly, though slightly less effectively than mint,” she says.

“When added to sugarcane juice and refrigerated, the microwave extracts kept the juice fresh for two weeks, with minimal changes to colour or flavour. By contrast, juice treated with methanol extracts deteriorated within a few days.”

The study also reflects shifting consumer expectations, according to principal investigator Dr Kashif Khan from the University of Agriculture, Faisalabad.

“People are becoming more cautious about synthetic additives, some of which are linked to health risks. Herbal extracts provide a safer, plant-based option that not only preserves juice, but may also add nutritional benefits,” Dr Khan says.

Beyond health benefits, microwave-assisted drying is faster, more sustainable and energy-efficient than conventional methods, making it suitable for producers of all sizes.

“Because this technology is simple and low-cost, it could be adopted by small and medium-sized juice producers in developing countries,” the team notes.

Future research will explore how these herbal extracts could be combined with pasteurisation or smart packaging to keep sugarcane juice fresher for even longer.