Выражение встречается в следующем контексте:

In general temperature should be kept low to protect the sucralose from chemical degradation. The GPCG-60 fluid bed unit may be operated in normal fluid bed agglomerator and/or coating mode (top spray or bottom spray) or in Wurster coating mode.

Spray agglomeration of neat sucralose was performed on Glatt GPCG-60 batch particle coater, using 18" Wurster insert available from Glatt.

Заранее спасибо