1 Yellow media without gas pocket-sugar utilization with production of acid only. 2  Red media (no change in media) -no change and no sugar utilization. 3  Pink media especially at the top, ignore gas-no sugar utilization with degradation of protein resulting in alkaline end products (this may be difficult to see).
With organic solvents with long alkane chain, such as n-hexadecane and n-decane, the water droplets become much larger and the microemulsion is unstable. In this case, solvent polarity may have become a determining factor and the long alkane chain was too hydrophobic to form a stable microemulsion with water.
n-Hexane (hereafter referred to simply as hexane) is a chemical made from crude oil. Pure hexane is a colorless liquid with a slightly disagreeable odor. It evaporates very easily into the air and dissolves only slightly in water. Hexane is highly flammable, and its vapors can be explosive. Pure hexane is used in laboratories.