UK scientific studies reveal major elements for developing fine chocolate
Cocoa harvests in Colombia were analyised by UK scientists for their fermentation characteristics. Pic: Adobestock
Some of the most significant elements responsible for shaping the flavour of fine grade chocolate have been identified in advanced studies at the University of Nottingham in the UK, writes Neill Barston.
Scientific analysis conducted at the University of Nottingham have completed analysis of Colombian cocoa production that has revealed precisely how taste characteristics evolve during the key fermentation process.
The results, which were published in Nature Microbiology, are believed to offer key breakthroughs for the sector that could potentially drive the development of widespread commercial confectionery production.
As the researchers noted, the team’s findings could pave the way for the production of next generation, consistently premium, flavour-rich chocolate that has remained in high demand in many areas of the world, despite financial pressures on consumers household spending budgets.
Moreover, as Confectionery Production has reported over the past year, these latest studies come amid a notable period of development for the sector, in which an ambitious group of businesses has pushed to develop alternative forms of production.
The emergence of companies such as US-based California Cultured, Kokomodo, and Planet A Foods, striving to devise either lab-grown cocoa strains, or using side-stream products that have been forged to provide a viable production stream that is seen as a means of meeting the enhanced level of international demand, rather than replacing existing traditional agricultural production.
As Nottingham university explained, scientific staff from its School of Biosciences examined how cacao bean temperature, pH, and microbial communities interact during fermentation and how these factors shape chocolate flavour.
From there, the team identified key microbial species and metabolic traits associated with fine-flavour chocolate and found that both abiotic factors (such as temperature and pH) and biotic factors (the microbial communities) are strong, consistent indicators of flavour development.
As the studies noted, flavour of chocolate has traditionally been influenced by climate condition, as with many other commodity crops – with global supplies, including in West Africa, having been hit this year with adverse conditions in Ghana and Ivory Coast impacting yields within the past two years.
This in turn has created a significant crop deficit, that has pushed up prices of cocoa to around $12,000 a tonne on US and UK Futures commodities markets, though this has dipped some way under $10,000 in recent months – still significantly higher than the rates of $3,000 a tonne that were the norm just a couple of years ago.
As for the fermentation process, this remains critical to the initial steps of flavour development. In addition, as researchers noted, it lays the foundation for aroma development, flavour complexity, and the reduction of bitterness in the final chocolate product.
Dr David Gopaulchan, the first author of the paper, from the School of Biosciences explains: “Fermentation is a natural, microbe-driven process that typically takes place directly on cocoa farms, where harvested beans are piled in boxes, heaps, or baskets. In these settings, naturally occurring bacteria and fungi from the surrounding environment break down the beans, producing key chemical compounds that underpin chocolate’s final taste and aroma. However, this spontaneous fermentation is largely uncontrolled. Farmers have little influence over which microbes dominate or how the fermentation process unfolds. As a result, fermentation, and thus the flavour and quality of the beans, varies widely between harvests, farms, regions, and countries.”
pic: Shutterstock
As the university explained, researchers wanted to find out whether this unstable, natural process could be replicated and controlled in the lab. Working with Colombian farmers during the fermentation process they identified the factors that influence flavour.
They were then able to use this knowledge to create a lab fermentation process and developed a defined microbial community, a curated mix of bacteria and fungi, capable of replicating the key chemical and sensory outcomes of traditional fermentations. This synthetic community successfully mimicked the dynamics of on-farm fermentations and produced chocolate with the same fine-flavour characteristics.
Dr David Gopaulchan added: “The discoveries we have made are really important for helping chocolate producers to be able to consistently maximise their cocoa crops as we have shown they can rely on measurable markers such as specific pH, temperature, and microbial dynamics, to reliably predict and achieve consistent flavour outcomes.
Significantly, the university noted that the research signals a shift from spontaneous, uncontrolled fermentations to a standardised, science-driven process.
Furthermore, the university compared the development to strides made in beer and cheese production, with greater control of microbes leading to the development of enhanced cocoa flavours, guided by that additional data. This is said to effectively be ‘domesticating’ the fermentation process, that had previously been dominated by conditions at source producing nations.
