Changes

* [https://www.youtube.com/watch?v=_oLPBnhOCjM Demonstration of gas diffusion; shows why "CO2 blankets" are very short term.]

* [https://www.youtube.com/watch?v=qaX7tiFQ2iA "Brewing with Brettanomyces Yeast and Mixed Cultures" presentation by Chad Yakobson at BC Craft Brewers Guild, 2019.]

==Commercial Brewer Interviews==