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Products · Chocolate · Mast

Mast Organic Dark Chocolate 80% Cacao, 2.5 oz bar

Reader ratings
Mast Organic Dark Chocolate 80% Cacao, 2.5 oz bar

Three organic ingredients: cacao, cane sugar and vanilla bean. Consumer Reports found it among the five lowest of 28 dark bars in both lead and cadmium, at 14 and 40 percent of California’s limits. The test dates from 2022 (two lots).

Best for Readers who want a plain 80% bar with the best independent metals result we found and will pay about $3.20 an ounce.

Our rating
Good (3.8 of 5)
Price range
Mid-range
Verified marks
USDA certified organic, vegan, kosher and gluten free, per the maker
Size
2.5 oz (about 71 g) bar
Made in
Made in Brooklyn, New York, per the maker. The bar’s page does not name the cacao’s origin; Kokoa Kamili in Tanzania is one of the cacao farms Mast lists.

approx. $8 for a 2.5 oz bar; $75 for a case of 10

See it on Mast’s site → (opens in a new tab)

We are not affiliated with Mast. This link goes to the maker’s own page, with no tracking code. How we're funded.

Also sold at Whole Foods Market (grocery listing) (price not captured), The Epicurean Trader ($8) .

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    Reviews are personal experiences, not research, and they never change our quality ratings. Every review is read by our team before it appears.

    How we evaluated it

    How it scores Our rating, metric by metric Good, 3.8 of 5
    1. Ingredients 25% of the rating 5 of 5

      Three organic ingredients, whole vanilla bean and no emulsifier; 80% cacao, the darkest bar Mast makes, and Whole Foods’ panel gives 7 g of sugar per half bar (35 g).

    2. Lead & cadmium 35% of the rating 4 of 5

      Consumer Reports, which the maker did not pay, put it among the five lowest in both metals (14 percent of the lead limit, 40 percent of cadmium), but the test is from 2022 and covers one bar, two or three samples from at least two lots.

    3. Sourcing 15% of the rating 3 of 5

      USDA organic and bean-to-bar, but this bar’s cacao origin and how farmers are paid are not stated on its page.

    4. Trust 10% of the rating 4 of 5

      No Prop 65 notice or FDA recall found; the company moved its shop to mastmarket.com, and its health claims stay modest.

    5. Value 15% of the rating 2 of 5

      About $3.20 an ounce at the maker.

    The rating, 3.8 of 5, is the weighted average of these scores. See how we rank chocolate and our standard.

    Where to buy Stores and the prices we saw 2 stores

    Prices as we saw them on November 6, 2026. They change often. These links carry no tracking code and earn us nothing.

    What’s in it Every ingredient, in label order 3 ingredients
    1. Organic cacao
    2. Organic cane sugar
    3. Organic vanilla bean
    Who tested it What each test found, and who paid for it 1 test
    • Independent Consumer Reports (28 dark chocolate bars; independent accredited lab, ICP-MS; published December 2022) December 2022

      Mast Organic Dark Chocolate 80% Cocoa was one of five bars with relatively low lead and cadmium. Consumer Reports’ chart gives 14 percent of California’s lead limit (0.5 µg) and 40 percent of its cadmium limit (4.1 µg) supplied by one ounce. CR tested two or three samples from at least two lot codes, bought in April and May 2022, and does not publish the individual lots. Open ↗ (opens in a new tab)

    Who paid, and why it matters
    • Independent The tester took no money from the maker for it: a consumer group, a journalist, a university or a regulator.
    • Paid certification An outside lab or certifier tested or listed it, and the maker paid for that.
    • Maker’s own test A lab report or certificate of analysis the maker commissioned and published.

    A certification is a floor, not a verdict: it checks what its program checks and nothing else. We weigh tests by someone with no stake in the result most.

    What people ask Worries raised online and elsewhere, and what we found 4 questions
    Does it contain lead and cadmium?
    Yes, a little: Consumer Reports found both in every bar. Mast’s result is the lowest on the list, at 14 and 40 percent of the California limits per ounce (the figures are in the chart on Consumer Reports’ page (opens in a new tab); Mamavation (opens in a new tab) repeats them). Results vary by lot, and Consumer Reports has not published a newer test of this bar.
    Is there a Prop 65 notice or recall?
    No notice names Mast (searched “Mast”, “Mast Brothers” and “Mast Chocolate” on the California Attorney General’s list (opens in a new tab) on 2026-11-05), and the FDA’s enforcement database shows no recall for Mast.
    Is organic chocolate lower in metals?
    No. Consumer Reports found organic bars as likely as others to be high, and Theo’s organic 85% was over both limits. Mast is low for its cacao and process, not because it is organic.
    How much sugar is in it?
    Mast says the 80% bar has the least sugar of its chocolates. The nutrition panel on Whole Foods’ listing (opens in a new tab) shows 7 g of sugars per half bar (35 g), about 14 g in the whole bar, with 7 g of fiber per half.
    Why we chose it What put it on our list 3 points
    • Consumer Reports named it among the five lowest of 28 dark bars for lead and cadmium together; 23 of the 28 went over a California limit at one ounce.
    • The list is cacao, cane sugar and vanilla bean, all organic, with no cocoa butter, emulsifier or flavor added.
    • It is 80% cacao, so less sugar than the 70% bars here.
    Trade-offs What to weigh before you buy 5 points
    • The one independent result is from 2022, for one bar; Mast posts no lot results of its own.
    • The page does not name where this bar’s cacao is grown or what farmers are paid.
    • At about $3.20 an ounce it costs more than Taza’s 70% bar.
    • Cadmium tends to rise with cacao percentage, so check any newer result before you eat it daily.
    • May contain traces of tree nuts and sesame, per the maker.
    What to know Details worth knowing first

    Mast makes this bar from three organic ingredients: cacao, cane sugar and vanilla bean. At 80% cacao it is the least sweet bar the company sells.

    Its case rests on one independent test. Consumer Reports measured 28 dark bars in 2022 and found lead and cadmium in all of them, with 23 over a California limit at one ounce. Mast was one of five that stayed low in both, at about 14 percent of the lead limit and 40 percent of the cadmium limit. The test is old and covers one lot, and Mast posts no results of its own, so we score it a 4, not a 5.

    The page does not say where this bar’s cacao grows. It costs about $3.20 an ounce.

    What we checked Each claim, and how sure we are of it 5 checks
    How Mast Organic Dark Chocolate 80% Cacao, 2.5 oz bar measures up against our chocolate criteria
    What we checked What we found
    Lead and cadmium measured by a lab the maker does not pay Verified Consumer Reports, samples bought April to May 2022, published December 2022: 14 percent of the lead limit and 40 percent of the cadmium limit per ounce, for the 80% bar.
    A short list: cacao, a named sweetener, perhaps cocoa butter or vanilla Verified Organic cacao, organic cane sugar, organic vanilla bean.
    70 percent cacao or more, sugar per serving stated Verified 80% cacao; 7 g sugars per half bar (35 g), from the Whole Foods panel.
    Traceable cacao, organic, how farmers are paid Maker’s claim USDA organic per the maker; origin and farmer pay not stated for this bar.
    No Prop 65 notice or recall Verified None found 2026-11-05.
    What the labels mean
    • Verified We opened an independent record that confirms it: a certifier’s listing, a regulator’s list or a lab report. It is linked under Sources.
    • Maker’s claim The maker says so on its own page or label. We read it but found no independent record.
    • Not verified We looked and could not confirm it, or the maker does not say. Treat it as unknown.
    Sources Where our facts come from 8 sources
    1. Mast: Organic Dark Chocolate 80% Cacao. Maker’s page. $8, 2.5 oz, ingredients. Open ↗ (opens in a new tab)
    2. Mast: farms. Maker’s page. Lists Kokoa Kamili, Tanzania, among its cacao farms. Open ↗ (opens in a new tab)
    3. Consumer Reports: Lead and Cadmium Could Be in Your Dark Chocolate. Test report. Chart row: Mast Organic Dark Chocolate 80% Cocoa, 14 percent of the lead limit and 40 percent of the cadmium limit per ounce. Open ↗ (opens in a new tab)
    4. Consumer Reports: test methodology for heavy metals in chocolate bars (January 2023). Test report. 2 to 3 samples of at least 2 lots per bar, bought April to May 2022; independent accredited lab. Open ↗ (opens in a new tab)
    5. Mamavation: dark chocolate lead and cadmium. Test report. Repeats CR’s chart: Mast 80% 14 percent lead, 40 percent cadmium. Open ↗ (opens in a new tab)
    6. Whole Foods Market listing. Independent source. Mast Dark 2.5 oz; nutrition panel (7 g sugars per 35 g). Open ↗ (opens in a new tab)
    7. The Epicurean Trader: Mast Organic Dark Chocolate 80%. Independent source. $8.00, in stock 2026-11-06. Open ↗ (opens in a new tab)
    8. California Attorney General: Prop 65 60-day notice search. Certifier or regulator listing. No notice for Mast, searched 2026-11-05. Open ↗ (opens in a new tab)
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