Abstract
Purpuse: Fodder yeast is obtained in an aerobic fermentation process where foaming is a major problem to be solved. In this article, the antifoam property of crude and purified filter cake oil is evaluated in order to use this residual as an alternative to replace the import of commercial antifoam agents and to reduce the production costs of fodder yeastMethod: Knock down test and the comparisons with two commercial antifoam agents were done. Blackstrap molasses medium at 20 and 40 g/L of total reducing sugar was used. All products were studied in their pure form and commercial ones also in dilutions 1:2 and 1:5 v/v. Hansen's solubility parameters (HSPs) to analyze the affinity of each defoamer for yeast were determined.Results: It was obtained the crude and purified filter cake oil showed similar behavior to commercial defoamers with an immediate antifoam effect, removing between 40 and 60% of the initial foam at both sugar concentrations in the first 5 minutes. The regression model showed purified filter cake oil has the greatest knockdown effect (Ca = 55.85 and 74.32) and with greater foam suppression stability the commercial defoamer Quimifoam Máster (Cb = -0.69 and -1.38). Ra values obtained in HSPs test, indicated the affinity of defoamers to the medium. Conclusion: Purified filter cake oil is an effective product for its use as an antifoam with the best knock down effect for both concentrations of sugars in the medium. The determination of HSPs corroborates the effectiveness of this product to suppress foam.
