As climate change and crop diseases tighten their grip on global cocoa supplies, scientists are exploring unexpected alternatives to protect the future of chocolate. Researchers at the National University of Singapore (NUS) have found that carob, a hardy and underused plant, could be transformed into a viable and sustainable substitute for cocoa through innovative enzyme-based techniques.
Cocoa production depends heavily on the Theobroma cacao tree, which grows only in narrow climatic conditions and is increasingly vulnerable to rising temperatures, erratic rainfall and disease outbreaks. These pressures have prompted scientists to look beyond traditional cocoa cultivation. Carob, derived from the tree Ceratonia siliqua, has emerged as a promising candidate due to its natural resilience to heat and drought.
Carob has long been known to develop a cocoa-like aroma when roasted, but its flavour has lacked the depth and bitterness associated with chocolate. This sensory gap has limited its acceptance as a true cocoa alternative. To address this, the NUS research team, led by Associate Professor Liu Shao Quan from the Department of Food Science and Technology, developed two novel techniques to enhance carob pulp’s flavour without adding artificial ingredients.
According to Liu, the innovation targets a largely untapped market for alternative chocolate sources while keeping ingredient lists simple. The goal, he said, is to improve carob’s natural taste so consumers can enjoy chocolate-like products that are both sustainable and appealing.
Carob trees are native to the Mediterranean region and thrive in hot, dry environments where water is scarce. Unlike cocoa trees, they can tolerate harsh growing conditions, making them better suited to a warming planet. Beyond climate resilience, carob offers nutritional benefits. It is naturally sweet, caffeine-free, and rich in d-pinitol, a compound linked to anti-diabetic effects. This makes it attractive to health-conscious consumers seeking alternatives to conventional chocolate.
Carob pulp is produced as a byproduct of locust bean gum manufacturing, commonly used as a thickener in food products. Despite its availability, differences in flavour compared to cocoa have prevented its widespread use in chocolate-making. The NUS team’s research aims to change that.
The first technique developed by the researchers uses enzyme-treated soy protein to enhance bitterness and deepen cocoa-like aromas in roasted carob pulp. This process increases amino acids and peptides, creating flavour compounds essential to dark chocolate. The findings were published in the Journal of Food Science in July 2025.
The second method focuses on boosting natural sweetness. By using enzymes to generate simple sugars within the carob pulp, roasting triggers reactions that produce sweet, caramel-like and roasted aromas. This approach was detailed in the journal Food Chemistry in June 2025.
Together, these methods recreate key flavour compounds that define chocolate, while also reducing some of carob’s less desirable natural odours. The result is a smoother, more familiar chocolate-like taste achieved through minimal processing. Since the enzymes used are already common in food production, the techniques can be scaled up easily for commercial use.
Researchers say improved carob pulp could be incorporated into products such as chocolate bars, cocoa powder, malt drinks and other cocoa-based foods. Widespread adoption could reduce the chocolate industry’s dependence on cocoa, helping stabilise supply chains threatened by climate change.
Manfred Ku, the study’s first author and a doctoral researcher at NUS, said the work is not just about copying cocoa’s flavour but about diversifying the ingredients used in chocolate alternatives. Turning to climate-resilient crops like carob, he said, could help the industry adapt to environmental pressures while still delivering enjoyable products.
Lower production costs may further strengthen carob’s appeal. As a byproduct of an existing supply chain, carob pulp could reduce agricultural waste and lower costs for manufacturers and consumers alike.
Looking ahead, the NUS team plans to explore additional techniques to refine carob’s flavour and introduce new taste profiles. They also aim to work with industry partners to commercialise the technology through licensing or collaborative ventures.
As climate risks grow and cocoa becomes harder to cultivate, carob’s transformation from a little-known crop into a chocolate alternative could offer a practical and sustainable path forward for the global confectionery industry.