This document describes the industry best practices to address the concentration of extracts which is related to ISO 16128-2:2017, 4.2. Evaporation of solvents to dryness it not addressed in this document.

This document aims to delineate the cases when an extract is produced and, afterwards the mixture of evaporated solvents used, regardless of the categories, are partially evaporated.

The producer of the extract can utilize different approaches (e.g. measurement by instrumentation, characterization of solvent volatility, published values of evaporation rates, etc.) to determine the index (es) of the extract. Despite the approach and justification, the rational and determinations used is made available to interested parties, when requested.