112 | How Does Heavy Metal Get Into Chocolate? | Honey Adulteration (a Duh Moment) |

Plus an OMG recall and cats cats cats

This is The Rotten Apple, an inside view of food integrity for professionals, policy-makers and purveyors. Subscribe for weekly insights, latest news and emerging trends in food safety, food authenticity and sustainable supply chains.

• Cadmium and lead in chocolate (how does it get there, what’s to be done?);

• From the Duh Files: Adulterated Honey study;

• Food Safety News and Resources;

• Yeasts, bacteria and viruses to scale (just for fun);

• Food fraud news, emerging issues and recent incidents

🎧 audio version 🎧

Wow there is so much going on in food safety this week! The UK authorities tested enoki mushrooms for Listeria monocytogenes and found it in almost one-third of samples. Enoki mushrooms have caused a number of Listeria outbreaks around the globe in recent years. Just to be clear, L. mono should not be in any food that will potentially be eaten raw.

Even more wow, the US FDA announced an OMG (oh my goodness) recall of fruit puree baby food that caused at least four children to show signs of acute lead intoxication, and which contained “extremely high” concentrations of lead. Unbelievable! Find that story, and the enoki mushroom warning in this week’s Food Safety News.

Also wow, one thousand cats were rescued when police interrupted a food fraud operation. Can you guess what part of the food supply chain they were destined for? Find out in this week’s food fraud news.

Welcome to Issue 112. A huge thank you to everyone who has renewed their subscription recently. And to our new subscribers, 👏👏 Lillian, Elena and ‘Info’ 👏👏 : it’s people like you who keep this newsletter high-quality and ad-free (and pay our wages!).

So… I was eating chocolate when I started drafting this issue. Then I stopped. Does chocolate in Australia have as much heavy metal contamination as chocolate in the USA? I don’t know, but I have tried to unpack some of the issues around chocolate, lead and cadmium in this week’s post.

Also this week, a duh moment in honey adulteration research, plus a cool 3 minute animation of yeasts, bacteria and viruses.

As always there’s food fraud news and incidents at the end for paying subscribers, who can also enjoy this easy-listening 🎧 audio version 🎧 (Aussie accent included 😏).

Thank you for being here,

Karen

P.S. “Elegantly curated” and “Highly recommended” are two of the nice things our subscribers said when they signed up. Paid subscribers get access to indexed posts, downloadable past issues and monthly supplements. Click the button to learn more.

---

Cadmium and Lead in Chocolate

How does it get in? What can be done?

Long-term exposure to heavy metals cadmium and lead results in nervous system damage, immune system suppression and kidney disease.

So it’s kind of worrying to chocolate addicts (like me) to discover that chocolate products in the USA contain levels of heavy metals high enough to cause harm in consumers who eat them regularly. It’s likely that chocolate in other countries is also affected.

Dark chocolate – which is usually considered more healthful than other chocolate, because of its lower sugar content and higher concentration of beneficial components – is the worst for heavy metal contamination. Drats.

Chocolate addicts beware… Some US products contain cadmium and lead at worrying concentrations. Photo by Michele Blackwell on Unsplash

Contamination levels explored

Last year, the U.S. consumer group Consumer Reports surveyed 28 dark chocolate bars. They found heavy metals in all the bars and very concerning levels in 23 of the bars. That’s 82%!

The survey’s authors said at the time: “For 23 of the bars, eating just an ounce a day would put an adult over a level that public health authorities and CR’s [Consumer Reports] experts say may be harmful for at least one of those heavy metals. Five of the bars were above those levels for both cadmium and lead.”

In the wake of the publishing of those survey results, many of the brands accused of having too-high levels have been sued by consumers in the US.

The same consumer group has again surveyed chocolate, this time expanding beyond chocolate bars and testing 48 samples from seven product categories: cocoa powder, chocolate chips, milk chocolate bars, and mixes for brownies, chocolate cake, and hot chocolate. The results of this most recent survey were published last week.

The group used California’s maximum allowable dose levels (MADL) for lead and cadmium in non-chocolate foods, set at 0.5 micrograms per day and 4.1 micrograms per day, plus serving sizes, for safety comparisons.

Why use ‘non-chocolate’ levels? Californian limits for heavy metals in chocolate foods were made less stringent than other foods after legal action by the (U.S.) National Confectioners Association in 2018.

The recent survey again found “worrisome” levels of cadmium and lead in chocolate products. One-third of the 48 products had “worrisome” levels and some products contained more than twice as much as “acceptable” limits. For example, a one-ounce serving of Perugina 85% Premium Dark Chocolate exceeded California’s maximum allowable dose level (MADL) for lead. By a factor of five. Evolved Signature Dark 72% Cacao Chocolate Bar contained more than twice as much lead as the MADL, and one and a half times as much cadmium as the MADL.

The brand Hersheys was called out for problematic results for its cocoa powder, milk chocolate and dark chocolate.

There is no suggestion that any of the products failed to meet legal limits. The USA does not have federal legal limits for heavy metals in most foods.

The National Confectioners Association responded by referring to its past legal battles in which it successfully fought for amendments to Californian limits saying: “An expert investigation conducted through our prior California Proposition 65 settlement concluded that cadmium and lead are present in cocoa and chocolate due to soil and that bean cleaning during processing cocoa beans reduces lead and cadmium in chocolate products.” Righto.

The US FDA also pretended unconcern, saying “Chocolate is a minor source of exposure to these contaminants [cadmium and lead] internationally.”  Does that mean some heavy-metal-vulnerable populations get more lead exposure from poisonous water pipes than from chocolate? Probably. Does that make it okay to have high levels in chocolate which some of us binge on? Nope.

Silver lining: Consumer Reports also tested the 48 chocolate samples for arsenic and mercury and those results were fine.

Dark chocolate products tested by Consumer Reports, showing percentage levels of acceptable levels for lead and cadmium. Image: Consumer Reports

How does heavy metal get into chocolate?

If you’re a food scientist you’re probably already shaking your head saying “but it’s impossible to completely eliminate heavy metals from cocoa supply chains”. And you’re not wrong.

But read on, because even the National Confectioners Association agree that there are effective strategies for reducing levels in chocolate.

In other words, high levels are 100% preventable. (Phew).

Cocoa growers and chocolate manufacturers can act to prevent high levels of contamination

Cadmium gets into chocolate because it is present in cocoa beans. The cocoa plant takes up cadmium from soil, through its roots, and the cadmium ends up in the nibs (centres) of cocoa beans, from which chocolate is made.

Cadmium is present as a natural component of soils in some areas, and is also a man-made contaminant of soils. Latin American and Caribbean cocoa growing regions can have “higher” levels of cadmium than other areas (source).

Lead gets into chocolate through contamination of cocoa beans after harvesting, during fermenting and drying processes. It is not taken up from soils through the roots of cocoa plants. Lead contamination is present in soil, dust and other airborne industrial pollutants which stick to mucilage on the beans while they are fermenting.

Cocoa beans are susceptible to lead contamination during fermentation

What can be done?

A report written by a panel of experts and published by As You Sow (shareholder advocacy nonprofit) and the National Confectioners Association describes methods for reducing levels of cadmium and lead in chocolate. Some of the “highest confidence” strategies from their report are listed below.

The report was published in 2018… I wonder if these recommendations have already been implemented in the supply chains of brands which fared poorly in the recent Consumer Reports tests…. Or not?

Cadmium level reductions can be achieved by:

• blending beans or liquor (blend high cadmium batches with low cadmium batches);

• not purchasing beans from regions with high phytoavailable cadmium soils.

Recommendations for farmers and growers include:

• stop planting cocoa orchards in regions with high cadmium phytoavailability;

• use soil amendments to increase soil pH;

• use plant grafting techniques to reduce cadmium uptake by cocoa plants;

• find plant varieties which accumulate less cadmium.

Lead contamination can be reduced by:

• protecting cocoa beans from contact with dirt, dust and other aerial contamination during fermenting and drying;

• prevent contamination of whole wet beans during transport;

• establish bean cleaning or winnowing practices to reduce lead contamination;

• test surfaces of cocoa beans for lead contamination at the point of purchase;

• make sure painted surfaces which contact the beans do not contain lead;

• use irrigation water that is free from lead.

In short: 🍏 Two surveys have found worrying levels of lead and cadmium in a significant proportion of chocoalte products in the USA 🍏 Lead and cadmium get into chocolate via cocoa beans 🍏 Cadmium gets into cocoa beans before harvest, by plants taking cadmium from the soil into the beans 🍏 Lead gets into cocoa beans during post-harvest processing, including fermenting and drying 🍏 There are strategies for making chocolate with low levels of lead and cadmium 🍏 It is unclear whether the brands that performed poorly in the surveys are using these strategies 🍏

Sources:

NCA. (n.d.). Research Reveals Ways Lead and Cadmium in Chocolate May be Reduced. [online] Available at: https://candyusa.com/news/research-reveals-ways-lead-and-cadmium-in-chocolate-may-be-reduced/.

‌Expert Investigation Related to Cocoa and Chocolate Products: Final Report Ahn, T., Chaney, R., Dibartolomeis, M. and Ramtahal, G. (n.d.). Available at: https://candyusa.com/wordpress/wp-content/uploads/2022/08/Prop65-Settlement-Final-Report-FULL-TEXT-update.pdf.

‌Flynn, D. (2023). Chocolate makers say they have heavy metals issue under control. [online] Food Safety News. Available at: https://www.foodsafetynews.com/2023/10/chocolate-makers-say-they-have-heavy-metals-issue-under-control/#more-233412 [Accessed 30 Oct. 2023].

‌Consumer Reports. (2023). A Third of Chocolate Products Are High in Heavy Metals, CR’s Tests Find. [online] Available at: https://www.consumerreports.org/health/food-safety/a-third-of-chocolate-products-are-high-in-heavy-metals-a4844566398/ [Accessed 30 Oct. 2023].

---

Food Safety News and Resources

Our news and resources section includes not-boring food safety news plus links to free training sessions, webinars and guidance documents: no ads, no sponsored content, only resources that I believe will be genuinely helpful for you.

😯 This week’s news has an OMG recall due to “extremely high” lead in baby food that caused at least 4 children to get lead intoxication. Wow. 😯

Click the preview box below to access it.

---

From the Duh Files: Adulterated honey is less appealing to consumers than pure honey

(Trigger warning for sensory scientists, I don’t intend to offend but probably will)

Honeys with 20% and 40% adulteration were located in the 40% and 80% preference regions in the PREFMAP. The adulterated honey with 60% and 80% had the lowest preference, causing their total rejection. Data source: Ramón‐Canul et al (2023). Graphics by author

Honey is one of the most fraud-affected foods on the planet. Frauds include the addition of foreign sugars and water, fraudulent claims about origin or floral varieties, even 100% “fake” honey made with syrups and colours.

Honey fraud is devastating for beekeepers and honest honey producers. But is it really a problem for consumers? (spoiler alert, I say yes!)

Sensory scientists wanted to know if consumers cared about the taste and feel of adulterated versus pure honey. They presented 130 consumers with samples made to mimic fraudulently adulterated honey and pure honey and used two scientific sensory techniques (pivot profile and CATA) to measure preferences and infer emotional associations. 

The most heavily adulterated honey was associated with lower preferences and with negative emotions including ‘aggressive’, ‘disgusted’, ‘bored’ and negative memories including ‘pain’, ‘interpersonal conflict’ and ‘poverty’. 

The researchers concluded, “An increase in honey adulteration was associated with negative emotions and memories evoked in consumers that may lead to the rejection of honey.”

Source: Ramón‐Canul, et al. (2023). Pivot© and check‐all‐that‐apply techniques for the analysis of honey adulteration: impact on consumer liking, emotions and memories. International Journal of Food Science & Technology, 58(7), pp.3865–3875. doi: https://doi.org/10.1111/ijfs.16488.‌

---

Yeasts, bacteria, viruses, to scale (just for fun)

This beautifully imagined 3.33 minute video zooms us in to the microscopic world of yeasts, bacteria and viral particles, starting at the size of a fly for scale.

Click the link below to watch.

---

What you missed in last week’s email

• Sample sizes for food safety tests;

• Packaging chemicals safety - new information;

• An underestimated (new) food pathogen (Helicobacter pullorum) - does it cause Crohn’s disease?

• A big knife is still a big knife (just for fun);

• Food fraud news, emerging issues and recent incidents

---

Below for paying subscribers: Food fraud news, horizon scanning and incident reports

📌 Food Fraud News 📌

Wow (nasty)

Thanks to Richard from MQM Consulting for alerting me to this month’s nastiest food fraud.

One thousand cats have been rescued after a tip-off from animal welfare activists resulted in the unearthing of a large cross-country illicit trade in