Allergen + diet flags, dairy, nut, soy, gluten, vegan. How searchable?

Chocolate allergens are unforgiving: dairy, nut (peanut + tree nut), soy, gluten, and cross-contamination warnings (“made in a facility that also processes…”). Vegan, kosher, halal, organic add another layer. FDA requires the “Big 9” allergen disclosure on packaging; ecommerce needs the same rigor in product data.

The Magento setup:

• Custom allergen attribute set per product, multi-select with values: contains-dairy, contains-tree-nut, contains-peanut, contains-soy, contains-gluten, contains-egg. Plus diet flags: vegan, vegetarian, kosher-OU, kosher-OK, halal, gluten-free-certified, organic-certified, fair-trade-certified.
• Layered navigation filters at category, customer filters to “dairy-free truffles,” “nut-free chocolate bars,” “vegan + kosher.” Magento indexes these natively.
• Allergen badge row on PDP, visual icons (Hu Kitchen pattern) with click-to-expand cross-contamination warning. Mandatory legal copy below price.
• Cross-contamination warning rendered separately from the “contains” list, FDA-compliant “may contain” disclosures for shared-facility production.
• Search relevance, “dairy-free truffles” returns the correct products because the attribute is indexed in Elasticsearch / OpenSearch with the right synonym handling (“dairy-free” ≡ “non-dairy” ≡ “DF”).

Hu Kitchen, Vosges, and Hu’s wellness-positioned competitors ship this pattern. Mandatory for any chocolate brand serving the wellness / allergen-restricted market. Shopify can approximate with apps but the search-relevance + cross-contamination layer is consistently weaker.