
Science Daily · Mar 1, 2026 · Collected from RSS
Scientists in Brazil have transformed cocoa waste into a functional chocolate-infused honey packed with antioxidants and natural stimulants. Using ultrasound waves, they enhanced honey’s ability to pull beneficial compounds from cocoa shells—no synthetic solvents required. The process is considered green and sustainable, and the product could find its way into gourmet foods and cosmetics.
Researchers at the State University of Campinas (UNICAMP) in São Paulo, Brazil, have created a new product that blends native bee honey with cocoa bean shells. The result can be eaten on its own or added to foods and cosmetic formulations. The findings were published in ACS Sustainable Chemistry & Engineering, which highlighted the study on its cover. To make the product, the team used honey from native bees as a natural, edible solvent to draw out beneficial compounds from cocoa shells, a byproduct typically discarded during chocolate production. These compounds include theobromine and caffeine, which are linked to heart health. The ultrasound-assisted process also boosted the honey's levels of phenolic compounds, known for their antioxidant and anti-inflammatory effects. Researchers who sampled the mixture report a pronounced chocolate flavor that varies depending on the proportion of honey to cocoa shells. Additional testing is planned to further evaluate taste and other sensory characteristics. "Of course, the biggest appeal to the public is the flavor, but our analyses have shown that it has a number of bioactive compounds that make it quite interesting from a nutritional and cosmetic point of view," says Felipe Sanchez Bragagnolo, the study's first author. He carried out the research during his postdoctoral work at the Faculty of Applied Sciences (FCA) at UNICAMP in Limeira with support from FAPESP. Working with INOVA UNICAMP, the university's innovation agency, the team is now seeking a commercial partner to license the patented method and bring the product to market (read more at agencia.fapesp.br/52969). Native Bee Honey and Biodiversity Beyond reducing food waste, the project highlights the sustainable use of local biodiversity. Honey from native Brazilian bees was selected because it generally contains more water and is less viscous than honey from European bees (Apis mellifera), making it more effective for extracting compounds. The researchers tested honey from five Brazilian species: borá (Tetragona clavipes), jataí (Tetragonisca angustula), mandaçaia (Melipona quadrifasciata), mandaguari (Scaptotrigona postica), and moça-branca (Frieseomelitta varia). Cocoa shells were supplied by the São Paulo State Department of Agriculture and Supply's Comprehensive Technical Assistance Coordination Office (CATI) unit in São José do Rio Preto. Mandaguari honey was initially used to refine the extraction process because its water content and viscosity were moderate compared to the others. Once optimized, the same procedure was applied to the remaining honey varieties. Bragagnolo notes that honey is sensitive to environmental factors such as climate, storage, and temperature. "Therefore, it's possible to adapt the process to locally available honey, not necessarily mandaguari honey," he says. Green Chemistry and Ultrasound Extraction The extraction method relies on ultrasound technology. A probe that resembles a metal pen is inserted into a container holding the honey and cocoa shells. Sound waves generated by the probe help release compounds from the plant material so they dissolve into the honey. This approach works by forming microscopic bubbles that collapse and briefly raise the temperature, helping break down the shells. In the food industry, ultrasound-assisted extraction is viewed as an environmentally friendly technique because it is faster and more efficient than many conventional methods. Sustainability was formally evaluated in the study using Path2Green software, developed by a team led by Professor Mauricio Ariel Rostagno of FCA-UNICAMP, who also supervised Bragagnolo's postdoctoral research and coordinated the project. The analysis measured how well the process aligned with 12 principles of green chemistry, including transportation, post-treatment, purification, and application. The use of a local, edible, ready-to-use solvent was a major advantage. On a scale of -1 to +1, the product received a score of +0.118. "We believe that with a device like this, in a cooperative or small business that already works with both cocoa and native bee honey, it'd be possible to increase the portfolio with a value-added product, including for haute cuisine," Rostagno suggests. Shelf Life and Future Applications The team is also planning studies to examine how ultrasound affects honey microbiology. Just as it breaks down plant cells, ultrasound can disrupt the cell walls of microorganisms such as bacteria that may spoil the product. "Honey from native bees usually needs to be refrigerated, matured, dehumidified, or pasteurized, unlike honey from European bees, which can be stored at room temperature. We suspect that, simply by being exposed to ultrasound, the microorganisms contained in the honey are eliminated, increasing the stability and shelf life of the product," he explains. Looking ahead, the researchers intend to explore other uses for native bee honey as a solvent in ultrasound-assisted extraction, including processing additional plant residues. Along with postdoctoral fellowships and an international research internship for Bragagnolo, the project received multiple scholarships and grants from FAPESP (23/02064-8, 23/16744-0, 21/12264-9, 20/08421-9, 19/13496-0, and 18/14582-5.