- Chocolate is derived from cocoa beans, the fruit of the Theobroma cacao tree in the Malvaceae plant family.
- Between 1998 and 2018, at least 55 chocolate-associated outbreaks were reported to CDC’s National Outbreak Reporting System (NORS), causing 1,054 illnesses, 26 hospitalizations, and no deaths.
- Most outbreaks in chocolate have resulted from added ingredients or in-plant contamination, such as the 2006 Salmonella Montevideo outbreak caused by a leaking waste water pipe in the processing plant. Undeclared allergens have frequently been the cause of chocolate product recalls.
- A number of stages are required in the processing of chocolate including hand harvesting pods, extracting cocoa seeds, fermenting, drying, roasting, shelling, alkaline treatment, grinding, conching to reduce the particle size, tempering, and finally molding into the final form.
- U.S. per capita consumption of chocolate is about 10 pounds per year.
- Although it should be consumed in moderation, several antioxidants and beneficial flavonoids have been associated with chocolate, especially dark chocolate.
BCE, when civilizations in Mesoamerica enjoyed the treat as a bitter drink. Cocoa beans were processed in a manner similar to methods used today. The Aztecs and Mayans believed this chocolatey drink held spiritual powers, making it a sought-after commodity throughout Central America. The arrival of Spanish explorers in 1528 brought an end to the Aztec civilization, but their chocolatey drink was taken back to Europe where it began to evolve into into the sugary sweet we are familiar with today.
Cocoa beans are derived from the Theobroma cacao tree species. There is no definitive place of origin for cocoa. Even though the genus Theobroma originated in South America millions of years ago, the exact origin of cocoa has never been made clear. Cacao trees grow best in humid, tropical climates, so most cocoa producing farms are within 10 degrees of the equator. The majority of cocoa producers are small farm owners located in West Africa in Ghana and the Ivory Coast; Indonesia is the top producer in the Pacific. The three cacao tree varieties are Criollo, Forastero, and Trinitario. Although Criollo is considered the highest quality cocoa, Forastero is the most popular due to its high yield of beans. The flavor of the beans not only depends on the tree variety, but also on the type of soil and on climatic conditions such as the amount of sunshine and rainfall.
Chocolate has been associated with foodborne outbreaks including Salmonella spp. and Escherichia coli. Outbreaks related to chocolate are rare, but the combination of various ingredients and the resistant nature of pathogens like Salmonella elevates the risk. Chocolate is considered a dry or low water activity product, which is typically not the ideal habitat for Salmonella. In some cases, traces of the pathogen from the cocoa bean can sometimes survive the thermal temperatures during the roasting process and dwell in the high-fat matrix of chocolate products. However, most outbreaks in chocolate have been the result of outside contamination from added ingredients or in-plant contamination, rather than pathogens traced back to the cocoa beans themselves.
The most recent Salmonella outbreak associated with chocolate occurred in 2006, when products of the British candy company Cadbury Scheppes were contaminated with Salmonella Montevideo. Investigation into this outbreak found that a leaking wastewater pipe that dripped into the milk chocolate crumbs during processing and mixed with various chocolate products. This contamination led to 37 Salmonella infections and three hospitalizations, all of which were children. In response to this outbreak, approximately one million Cadbury chocolate items were recalled on June 23rd, 2006. Upon further investigation, it was revealed that Cadbury had been aware of the pipe and initiated repairs but failed to issue a recall notice because they determined the extent of the Salmonella contamination was not significant enough to warrant action.
Import and Export:
The global trade of chocolate ranks 129th in trade, with approximately $29.2 billion total trade value in 2018. In 2018, the United States were the world’s top importers of chocolate at $2.76 billion, ahead of both Germany and the United Kingdom. That same year the U.S. ranked sixth in the world for chocolate exports at $1.64 billion, ranking behind Germany, Belgium, Italy, the Netherlands, and Poland.
The production of chocolate products involves two main stages: (1) harvesting and processing of cocoa, and (2) manufacturing of chocolate and chocolate products.
Harvesting and Processing of Cocoa
Chocolate is derived from cocoa beans, which are the products of cacao trees found in several different regions, all located near the equator. The majority of cocoa is produced in Brazil, Cameroon, Côte d’Ivoire, Indonesia, and Ghana. Each cacao tree bears pods holding about 20–50 wet beans. A single pound of chocolate requires at least 400 beans from these cacao pods. The pods must be harvested manually and then broken open. After being extracted from the pods, cocoa beans are fermented, usually by being piled on the ground and covered with leaves. During this fermentation stage, microorganisms (mainly yeasts) begin to grow. Over the course of a few days, the beans undergo chemical activity which allows the chocolate flavor and color to develop. The cocoa beans are then dried out by sun drying or artificial drying in order to significantly reduce their moisture content. The dried cocoa beans are transported to processing facilities to be cleaned and sorted before being used in the production of chocolate products.
Manufacturing of Chocolate
The manufacturing process begins by first roasting the cocoa beans to kill bacteria and enhance flavor. After roasting, they are shelled and basted with an alkaline treatment to further develop flavor. The beans then go through a grinding and refining phase that extracts the cocoa butter and cocoa liquor from the bean nibs, or the “meat” of the bean. Additional ingredients such as milk and sugar can then be added. A processing step called conching then reduces the particle size of cocoa solids and sugar crystals, giving the chocolate its well-known texture and mouthfeel. Finally, the conched chocolate is tempered through heating and put into molds to be cooled.
Food safety concerns for chocolate arise during both stages of production (harvesting and manufacturing). Because cocoa beans are generally harvested in countries other than those that will process the chocolate, food safety practices may differ. Thus, the importance of food safety in the final processing steps is extremely important. Nations that produce the largest quantities of cocoa tend to be in lower-income countries. Cocoa farmers must comply with International Cocoa Organization (ICCO) regulations, but due to the financial burden of adhering to these regulations some farms might not meet the proper standards. Some importing countries implement Sanitary and Phytosanitary (SPS) standards that require cocoa producers to abide by all safety measures before exporting their beans. Even with stricter regulations and innovative technology, chocolate, like any other food, still poses some food safety risks in both raw and processed forms.
From cocoa bean harvesting to its transport for processing, it is at risk for physical, chemical, and microbial hazards. Physical hazards can include any foreign object that is acquired from the natural or synthetic environment, such as rocks, twigs, or pieces of metal from processing equipment. Chemical contamination can occur on the farm by way of heavy metals in the soil or use of pesticides, as well as unintentional exposure to chemicals used in the processing facility.
Microbiological contamination can occur at any of the processing phases, both on farm and in the manufacturing plant. Unclean hands of workers, equipment residue, insects, tools, baskets, and plant leaves are all media for pathogens to transfer to cocoa beans on farms. During the fermentation and sun-drying productions steps, cocoa beans are highly susceptible to fungi and mycotoxin contamination, mostly by aflatoxin and ochratoxin A. During transport, cocoa beans can be exposed to environmental pathogens if contamination is not controlled.
The chocolate manufacturing process addresses most of the food safety concerns specific to cocoa beans, such as on-farm pesticide contamination or physical hazards from the farm. Roasting, shelling, conching, and alkali treatments reduce the concentration and prevalence of aflatoxin and ochratoxin A in chocolate products. During processing, sources of physical contamination are removed via critical control steps such as sifting or metal detectors, and sources of microbiological contamination are reduced during a critical control step such as heating. Consumers who wish to eat chocolate in the “raw” or unroasted form should be aware that they are increasing their risk of getting Salmonella. High-temperature cocoa bean roasting is the primary way to ensure that no pathogens survive in the final product.
Although the homogenous nature of processed chocolate dilutes some biological hazards such as mycotoxins, it also has the potential to introduce new contaminants and pathogens via added ingredients. In addition to the chocolate liquor and cocoa butter derived from the cocoa beans, ingredients such as milk, sugar, nuts, dried fruits, and other common additives to chocolate can contaminate the final product.
In addition to the physical, chemical and microbiological hazards discussed above, allergic reactions to chocolate should not be ignored regarding food safety. From 2009 to 2013, roughly 11% of food allergen-related entries in the Reportable Food Registry were attributed to undeclared allergens in chocolates or like confections. This may be due to the cocoa plant itself or to the assortment of other ingredients commonly included in chocolate-based products such as milk, eggs, tree nuts, peanuts, and wheat, which are also five of the eight major food allergens. Generally, dark chocolate is safer alternative to milk chocolate or chocolate products for those with allergies and/or intolerances to these ingredients. However, because the safeness of such products is not always guaranteed, recalls and seeking a better understanding of the potential origins of undeclared ingredients are in order.
In the past ten years, there have been accounts of chocolate-containing products being recalled due to cross-contamination with common allergens. Mid-January of 2019, RXBAR voluntarily recalled several varieties of their nutritional bars due to undeclared peanuts. Of the 15 varieties, nearly half of them were chocolate flavored. Moreover, the FDA conducted a limited survey between September 2013 and September 2014 of dark chocolate products for presence of milk to estimate the prevalence of undeclared milk allergens in confections.
Researchers tested 94 chocolate bars and found that only six of them listed milk as an ingredient, whereas of the remaining 88 bars that did not list milk as an ingredient, 51 of them did contain milk. Although the data is limited, the study shows that undeclared ingredients in foods are an issue that needs more attention. It is also worth noting that the same equipment that makes dark chocolate also makes milk chocolate, which increases the risk of milk and other ingredients to be mixed in with products that should not contain the ingredient(s) during production.
The average American consumes about 10 pounds of chocolate every year, half the amount the average Swiss citizen consumes, which is approximately 24 pounds per year. Chocolate is consumed in a variety of forms: candy bars, desserts and baked goods such as ice cream, mousse, fondue, sauces/syrups, puddings, muffins, breads, cakes, brownies and cookies. It is also common as a spread, most notably, Nutella, and as a liquid including chocolate milk, milkshakes, hot cocoa, flavored coffee, and alcoholic drinks like brandy and crème de cacao.
The positive health benefits of chocolate are often overshadowed by its classification as ‘unhealthy’ or ‘junk food.’ Chocolate is a high-calorie food containing fat from the natural presence of cocoa butter. The fat from cocoa butter is comprised of oleic acid, the same monounsaturated fat found in olive oil. Additionally, cocoa butter contains saturated fat primarily as palmitic acid and stearic acid. The nutritional value of chocolate depends on how it is processed and the mixture of additional ingredients. The nonfat cocoa solids, found in cocoa powder and dark chocolate, contribute to health benefits through its content of antioxidants and flavonoids. Antioxidants help inactivate free radicals, reducing oxidation and the formation of plaque on artery walls. Flavonoids have been shown to lower blood pressure and improve blood flow to the brain and heart, which together with anti-inflammatory effects reduce risk of cardiovascular disease. Along with these bioactive compounds, cocoa solids are a good source of various minerals, including magnesium, copper, potassium, calcium and iron. Because milk chocolate has relatively low amounts of cocoa solids compared to dark chocolate, dark chocolate is significantly higher in both bioactive compounds and micronutrients. Milk chocolate is a more processed type of chocolate because it contains a higher content of other high-calorie and high-fat ingredients such as milk and sugar products. Chocolate, even dark varieties, should be eaten in moderation.
- Affairs O of R. RXBAR Recalls Certain Varieties of Bars Due to a Potential Undeclared Peanut Allergen [Internet]. U.S. Food and Drug Administration. FDA; 2019 [cited 2020 Jun 5]. Available from: https://col.st/0wPO0
- Beckett S. Food Safety in Chocolate Manufacture and Processing. In: Industrial chocolate manufacture and use. 4th ed. Oxford: Blackwell Publishing; 2009.
- Commissioner O of the. Dark Chocolate and Milk Allergies. FDA [Internet]. 2019 Feb 9 [cited 2020 Jun 5]; Available from: https://col.st/k3tBo
- Copetti MV, Iamanaka BT, Pitt JI, Taniwaki MH. Fungi and mycotoxins in cocoa: From farm to chocolate. International Journal of Food Microbiology. 2014 May 16;178:13–20.
- Katz DL, Doughty K, Ali A. Cocoa and Chocolate in Human Health and Disease. Antioxid Redox Signal. 2011 Nov 15;15(10):2779–811.
- Lund B. Cocoa, Chocolate, and Confectionery. In: Microbiological Safety and Quality of Food. Springer Science & Business Media; 2000. p. 951.
- Lund B, Baird-Parker AC, Gould GW. Microbiological Safety and Quality of Food [Internet]. Springer US; 2000 [cited 2020 Jun 5]. Available from: https://col.st/75140
- Nieburg O. Is the rise of raw chocolate a safety concern? [Internet]. Confectionery News. 2014. Available from: https://col.st/y5RId
- Nutrition C for FS and A. Survey of Milk in Dark Chocolate Products. FDA [Internet]. 2020 Feb 20 [cited 2020 Jun 5]; Available from: https://col.st/wcDDG
- Nutrition C for FS and A. What You Need to Know about Food Allergies. FDA [Internet]. 2020 Apr 20 [cited 2020 Jun 5]; Available from: https://col.st/8BLBN
- Werber D. International outbreak of Salmonella Oranienburg due to German chocolate. BioMed Central Ltd. 2005 Feb;Volume 5(BMC Infectious Diseases 2005, 5:7).
- Chocolate Facts [Internet]. Morkes Chocolates. 2011. Available from: https://col.st/nNJjz
- What is the origin of the cocoa tree? [Internet]. International Cocoa Organization. 2013. Available from: https://col.st/zIyv0
- The Cacao Tree – Facts About Theobroma Cacao [Internet]. Chocolate.org. 2015. Available from: https://col.st/s0cOG
- Whole Foods Market’s Glastonbury Store Recalls Divine Treasures 100,000 Smooches Vegan Chocolate Due to Undeclared Allergen [Internet]. Food Allergy and Anaphylaxis Connection Team. 2015. Available from: https://col.st/y2zS4
- Chocolate (HS: 1806) Product Trade, Exporters and Importers [Internet]. Observatory of Economic Complexity (OEC). [cited 2020 Jun 5]. Available from: https://col.st/3dfUA
- Lesson—How Chocolate is Made [Internet]. Ecole Chocolate. [cited 2020 Jun 8]. Available from: https://col.st/2ux3i