Harvest is the upstream bioprocessing step in which the biological product — such as a recombinant protein, viral vector, or cell population — is collected from the bioreactor or culture vessel at the end of the cell culture or fermentation process. The timing and method of harvest are critical process parameters (CPPs) that directly impact product yield, quality, and stability. Harvest operations typically include cell separation by centrifugation or depth filtration, followed by initial clarification steps to remove cell debris and prepare the harvest material for downstream purification.
