Oleoresin

Grinding a spice gives you aroma, color, heat and a lot of plant fiber. Distilling it gives you only the aroma. An oleoresin gives you the aroma and the heavy non-volatile part — the resins, pigments and pungent compounds — and leaves the plant material behind.

That heavy fraction is where a lot of a spice's character lives. Capsaicin in chili, piperine in black pepper, the color in turmeric, the deep body notes in ginger — none of those survive steam distillation. Which is why the essential oil version of those spices smells right and tastes incomplete.

Why manufacturers use them

Consistency. Oleoresins are standardized to a specified heat or color value, so a seasoning keeps its character across harvests.

Cleanliness. Ground spices carry bacteria. Extracts do not.

Efficiency. One kilo of oleoresin can replace twenty or more kilos of ground spice, which matters in high-volume seasoning and sauce production.

They are thick and usually will not disperse in water, so they are supplied either plated onto a carrier — salt, dextrose, silica — or emulsified. That carrier choice is a formulation decision of its own. See carrier.