I hope that everyone was thankful yesterday for friends, family and good food.

There is one thing that you may have neglected to give thanks for at your Thanksgiving table; it is an organism small and easily overlooked, but likely an important part of yesterday’s (and maybe everyday’s) meals: don’t forget the yeast that makes an important part of the feast!

Yeast is one thing that I would not like to live without. Ralph Waldo Emerson observed that “God made yeast, as well as dough, and loves fermentation just as dearly as he loves vegetation.” Me too, since in my household bread and fermented drinks would be sorely missed if this fungus was not among us.

Sacchoromyces cerevisiae, literally ‘sugar-eating fungus,’ is the simple and humble species that allows us our daily bread and beer (and wine, too). It is one of 1,500 known types of yeast. This is only a drop in the bucket of suspected yeast varieties, since it has been estimated that only 1 per cent of all wild yeasts have been discovered to date.

Yeasts are a simple single-celled organism, but with a history. While one doesn’t think of fungus when talking about domesticating wildlife, yeast is surely the first cultivated wild thing. More than 5,000 years ago, Egyptians were baking and brewing with these species. Interestingly, the ancient Egyptians also were known to treat infections with moldy bread, which is relevant here because members of the same family of yeast that cause bread to rise also produce such antibiotics as penicillin and streptomycin.

Yeasts were originally caught in the wild: spores are naturally found in the air and on plant leaves, flowers, soil, salt waters and in the intestinal tract of many animals.

Once captured, yeast can be tamed, exploited and coaxed into reproducing. Yeast grows optimally at around 86 degrees Fahrenheit in a slightly acidic environment. By consuming sugars, yeast will produce carbon dioxide and alcohol. In bread, the production of carbon dioxide aerates dough, expands it and provides flavor. Unleavened bread is for those who do not have (or want) dominion over yeast. Or, put another way by jazz vocalist Carmen McRae, “Blues is to jazz what yeast is to bread. Without it, it’s flat.”

We no longer have to capture yeast. In 1877, at the Centennial Exposition, Charles Fleischmann introduced the first commercial yeast. Today, Fleischmann’s and other brands can be easily purchased at the market.

Beyond the loaf, yeast also has benefits as a nutritional supplement. It consists of 50 per cent protein and is a rich source of B vitamins, niacin and folic acid.

A small organism, this fungus is about the size of a human red blood cell. It is very light, taking over 20 billion yeast cells to weigh only one gram. So although it could be said to be the best thing since — or in ­— sliced bread, yeast’s tiny size illustrates the maxim that “good things do come in small packages.”

We should be giving thanks for those little packages of yeast so readily available at the grocery store that make our daily bread. But after my diverse Thanksgiving meal, I would argue that man (or woman) should not live on bread alone.


Suzan Bellincampi is director of the Felix Neck Wildlife Sanctuary in Edgartown.