FER-1000 Lecture Notes - Lecture 9: Sulfur Dioxide, Sodium Hydroxide, Ph Meter
20 Mar 2017
School
Department
Course
Professor
Document Summary
What attributes or parameters do we want to monitor during a fermentation: sugars, organic acids, ph, metabolites (anabolic) Primary substrate carbon source: sugars or specifically fermentable sugars. Fermentations can be monitored via: refractometry, hydrometer, densitometer, enzymatic determination. Based on the refractive index of the solution. A relative measure of the amount of refraction occurring as light passes through a glass prism. Higher solute concentrations will result in a high angle of refraction (difference in transmission) What does this mean for accurate measurements: solutes other than sugars will alter the refractive index. Gage the density of a solution and compare that to the density of a reference (water at room temperature) Solutions with a high density (more solute / l solution ) will have sg > 1. 000. Problems with this: density (ethanol ) = 0. 789 g/ml, other solutes will contribute to changes in density also, must correct for temperature to be accurate. Electronic reading are between two points in capillary.
