Dried herbs, refrigeration and the other routes

Refrigeration buys days

Extension guidance puts fresh, unacidified herbs in oil at a matter of days under refrigeration rather than weeks, and peeled garlic submerged in oil at a few days refrigerated. Those are short enough that a refrigerated unacidified infusion is a kitchen practice rather than a product, and treating it as a product is how the hazard arrives.

Dried material is a different proposition

Dried herbs carry far less water, and published guidance allows a much longer hold for an oil made with them, measured in months rather than days. That is a genuinely different risk profile, and it is also a different product: a dried-herb infusion tastes different from a fresh one and most makers prefer the fresh.

Strained is not safer

Removing the solids after infusion does not undo anything. Whatever the material contributed while it sat there is in the oil, so a strained unacidified infusion is in the same position as an unstrained one. The appearance of a clear bottle is misleading in exactly the wrong direction.

Flavor without the solid

The route that avoids the question entirely is flavoring the oil with something that is not a low-acid solid sitting in it, which is what most commercial flavored oils do. It is a different craft and it makes a different product, and it is worth considering honestly rather than dismissing as inauthentic.

Whatever route you take, the label has to match

If the product is refrigerated, say so, and date it accordingly. The failure here is not usually a maker who does not know; it is a maker who knows and prints a shelf-stable date because a refrigerated product is harder to sell.

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