Costco’s grocery aisle displays chocolate chips from its private label, Kirkland Signature, alongside national brands like Ghirardelli and Nestlé. Each product is required to list ingredients in descending order, and any gluten‑containing grain such as wheat, barley, or rye must appear plainly. When a bag includes a ‘gluten‑free’ claim, it signals compliance with the FDA’s limit of less than 20 parts per million of gluten. Absent that claim, the presence of hidden gluten is possible, even if the taste is indistinguishable.
The gluten‑free status also depends on the manufacturing environment. Many chocolate chip producers operate shared lines that handle both gluten‑free and gluten‑containing products. Unless the packaging explicitly states ‘processed in a gluten‑free facility’ or uses a third‑party certification, the risk of cross‑contact cannot be dismissed. Therefore, diligent label reading is essential for anyone who must avoid gluten entirely.