Salmonella in Cocoa Beans, High Temperature
After an exhaustive search involving credible sources, we were unable to find any evidence concerning roasting cocoa beans at high temperatures (230 degrees) for a short amount of time (two minutes) is effective at removing the risk of salmonella.
Salmonella in Cocoa Beans, High Temperature
- Salmonella is considered to be an infectious organism and can be spread between various species of animals, including humans.
- Salmonella can be discovered in milk, raw meats, and other products originating from animals. Plants such as sprouts and vegetables that come into contact with contaminated water or animals can also help spread salmonella.
- Salmonella can also be found in low-moisture foods, as well as dry foods like nuts, chocolate, and infant formula.
- Cooking or heating food for about two minutes at 70° C (158 F) can eliminate salmonella. However, salmonella is more immune to heat and longer cooking times in conditions that involve low moisture or are dry. Hence, higher temperatures would be required.
- Artisan Chocolatier John Nanci, who also holds a degree in Chemistry, once conducted an analysis on cocoa beans contaminated with e.coli and salmonella while working as a chemist. The results displayed undetectable levels of pathogens after a five-minute high-temperature roast or a 40-minute cool roast.
- Mr. Nanci also states that the standard for sterilization in a hot air oven is around 160°C (320°F) for up to two hours. A quicker technique is six minutes at about 190°C (374°F).
- According to the National Confectioners Association, due to challenges in managing conditions on farms, all forms of raw cocoa should be deemed contaminated.
- Typically, cocoa beans are exposed to high temperatures during roasting for a precise time, which can diminish pathogens and produce flavor development. Some factors that should be acknowledged include belt speed/type of machine used, air distribution, bed depth, as well as moisture level, the incoming temperature of the beans, and size.
- There is a paywalled study published in the "International Journal of Food Microbiology" Volume 159, Issue 3, 15 October 2012, Pages 225-229 that discusses the high heat needed for the elimination of salmonella in cocoa beans. Though the article mentions temperatures of 110°C to 130°C (230°F to 266°F), the abstract for the study does not mention time roasted at that temperature.
Our research began by searching for studies on salmonella and cocoa beans on scientific sources such as the National Center for Biotechnology Information, Thermo Fisher Scientific, and the Food and Drug Administration, which provided us with information on salmonella. We also came across details on pathogens, including salmonella and the making of chocolate, as well as salmonella and other dry foods such as raw nuts. However, there was no information on salmonella and the time or temperature for roasting cocoa beans. Additionally, we researched scholarly sources such as Researchgate and Science Direct, where we found an older paywalled study on salmonella and cocoa bean roasting, which may contain useful information.
We then directed our search towards industry sources such as the National Confectioners Association, the Food Engineering Magazine, and the Journal of Food Protection, seeking industry reports on chocolate and cocoa. We were able to locate a white paper on cocoa beans. Also, we found multiple articles mentioning salmonella, but nearly all were about nibs, slurry, or chocolate storage. Again, there was no specific information on time or temperature of roasting cocoa beans. We also searched manufacturers such as Novolyze, which provides products and advice on eliminating pathogens from the cocoa bean, but we found no information on how their products work, like the time or temperature used.
Next, we explored artisan chocolate sites such as Chocolate Alchemy and the Chocolate Life, looking for information from these manufacturers on their practices in producing specialty chocolate. These sites had helpful advice for at-home chocolate makers, including warnings of contamination during all steps of chocolate making. Nonetheless, information on cocoa bean roasting and salmonella were only contained in one article published by a manufacturer with a chemistry degree, and it explains the roasting of cocoa beans and salmonella contamination.
Although we were able to find information indicating that salmonella can be destroyed in two minutes at a temperature lower than 230 degrees, this information does not apply to cocoa beans as it is a low-moisture food. The shortest time mentioned was five minutes, while the lowest temperature we found was 320 degrees.