The relationship between turbidity, measured using photodetectors and cell count is linear up to 60 million cells/ml. Using this principle an in-line instrument has recently been developed for measuring yeast cell count in pitched wort. By combining this instrument with automatic controls a system has been produced that can be used for the continuous, consistent and accurate dosing of yeast into wort. With minor modifications this technique can also be used to control other brewery operations such as krausening, secondary fermentations, yeast additions for Weissbier or cask conditioned ales and for the addition of processing aids e.g. filter aids, silica gel or PVPP.
Keywords : addition automation brewers' yeast brewing control pitching