White Labs WLP013 London Ale Yeast is a dry, malty ale yeast. It provides a complex, oakey ester character to your beer, and hop bitterness comes through well. This yeast is well suited for classic British pale ales, bitters, and stouts. White Labs yeast is world-renowned for quality and innovation, certified kosher, GMO free, and subject to thorough quality analysis before being packaged. This yeast comes packaged in White Labs' PurePitch packaging using the revolutionary FlexCell process, which creates yeast that has never been transferred or exposed to the environment. The PurePitch packaging is a recyclable, flexible material that allows for increased breathability, reducing the chance of gas buildup and maintaining the optimal environment for yeast.