Nutritional yeast is sourced from whey, blackstrap molasses or wood pulp. It is grown on molasses or a similar habitat.
Primary ingredient in the growth medium is glucose, often from either sugarcane or beet molasses. When the yeast is ready, it is killed (deactivated) with heat and then harvested, washed, dried and packaged.
Many vegan recipes include yeast to add an umami flavor. It has a strong flavor that is described as nutty, cheesy, or creamy, which makes it a popular ingredient in making cheese substitutes.
Store in a cool, dry place and away from heat and direct sunlight. Close tightly and consume as soon as possible once opened.