Why Some Powders Stay Free-Flowing

Caking is almost always a moisture problem.

Water on particle surfaces forms bridges between them. As it dries, those bridges harden into clumps.

Keeping moisture out

Filling dry Packaging happens in humidity-controlled conditions. Excess moisture at this stage cannot be corrected later.

Barrier packaging Aluminum-laminated pouches and tins resist moisture transmission. Some products include oxygen absorbers or nitrogen flushing.

Dextrin Produced by breaking down starch, it keeps powder free-flowing and prevents caking. A food ingredient rather than an additive, though it counts as carbohydrate.

Granulation Forming powder into small granules reduces surface area and lowers moisture sensitivity. Dispersion improves as a side benefit.

After opening, it is your problem

Packaging protects until the seal breaks.

Three things to avoid:

• A wet spoon in the package. Once moisture is introduced, caking spreads from that point.
• Opening a refrigerated container immediately. Room air condenses on cold interior surfaces. Let the sealed container reach room temperature first.
• Humid storage. Under the sink, near a rice cooker, anywhere steam collects.

If it has caked

Moisture is present. Breaking up light clumps with a dry spoon works, and passing it through a strainer evens the texture — but flavor has already suffered, so use it soon.

Stop if the smell has changed or the color has visibly shifted.

The other side of very free-flowing

Products with flow agents handle easily but carry more ingredients.

Matcha-and-sugar-only formulations cake more readily. Working the powder into a paste with a small amount of liquid before adding the rest resolves the practical difficulty almost entirely.