From breakfast toast to evening wine, yeast is the microscopic thing that we cannot live without. We knew what yeast did as an invisible brewer and baker long before we had a clue about the existence of microorganisms. Ten thousand years ago, our ancestors abandoned bush meat and wild fruit in favour of farming animals and cultivating grain. Leaving the forests and grasslands, our desire for beer and wine produced by the fungus was a major stimulus for agricultural settlement. It takes a village to run a brewery or tend a vineyard. We domesticated wild yeast and yeast domesticated us. With the inevitable escape of the fungus from beer vats into bread dough, our marriage with yeast was secured by an appetite for fresh loaves of leavened bread.
Over the millennia, we have adapted the technologies of brewing, winemaking, and baking and have come to rely on yeast more and more. Yeast produces corn ethanol and other biofuels and has become the genetically-modified darling of the pharmaceutical business as a source of human insulin and a range of life-saving medicines. These practical uses of yeast have been made possible by advances in our understanding of its biology, and the power of genetic engineering has been used to modify the fungus to do just about anything we wish. We know more about yeast than any other organism built from complex cells like our own. To understand yeast is to understand life. In The Rise of Yeast, Nicholas P. Money offers a celebration of our favourite microorganism.
"Yeast rises our bread, ferments our beer, wine, and spirits, perfumes our fruit, nourishes our bodies, makes us bold in love, foments chaos, powers our cars, and unlocks the soul. We humans tend to think that we rule the earth, but the evidence on our behalf is scant. This fascinating book unlocks the mysteries of our world's true masters, which were here before we walked, will be here when we're gone, and, in the meantime, help make our time on the planet a lot more fun and infinitely more delicious."
– Garrett Oliver, Brewmaster of the Brooklyn Brewery, Editor-in-Chief, The Oxford Companion to Beer
1: Our Favourite Microbe
2: Yeast of Eden
3: Raising Bread/The Dough Also Rises
4: The Sugar Cell
5: Yeast Our Redeemer
6: The Other Yeasts
7: Our Yeasts in Sickness and in Health
From the Giza-pyramid-complex-shaped mountains of dried yeast to the visual joke on the spine (I see what you did there), The Rise of Yeast is an amusing read about fungus. In case you find that hard to believe, Nicholas P. Money, mycologist and professor of Botany, has been waxing lyrically about micro-organisms for years. Here, he highlights the humble yeast and how it has shaped human history. For without yeast there would be neither bread nor booze.
After a short introduction to the basics of yeast biology – including how it metabolises sugar and creates alcohol – and how yeast was discovered, Money first takes a look at fermentation in the wild and a host of nature's tipplers. Fruit bats, treeshrews and elephants all encounter alcohol, but not all get drunk despite anecdotes to the contrary. Rather, it signals the nearby presence of sugary nectar on which yeast thrives. Our primate ancestors evolved the ability to quickly metabolise alcohol and Robert Dudley went so far as to suggest that the behaviour that evolved to find ripe and overripe fruit explains our attraction to alcohol (see The Drunken Monkey). But it was not until we learned to brew with yeast that we managed to push up alcohol levels sufficiently to inebriate ourselves. Money takes us through the archaeological evidence for the brewing of wine and beer, noting how some have even gone so far as to suggest that the prime reason for humans settling down was to provide brewers with the raw materials they needed.
The other well-known role for yeast is of course in baking bread, for which evidence can be traced back to the ancient Egyptians. Money takes the reader on an amusing historical tour of the use of yeast in manufacturing bread and other food products. But yeast has also played an important role in basic scientific research. Its genome has been completely sequenced, and the function of its genes has been elucidated. Researchers are currently working on a completely synthetic version of yeast, rewriting its DNA from scratch and leaving out millions of years of evolutionary baggage, while maintaining its functionality. This synthetic organism could be completely re-engineered to meet our needs.
This leads into the most technical chapter of the book on the use of yeast in biotechnology. Yeast has been a workhorse in the production of biofuels, insulin for diabetes patients, and various vaccines. The Gates Foundation is funding ongoing research into modifying yeast to produce artemisinin, an anti-malarial drug.
Finally, Money gives an overview of the evolutionary diversity of wild yeasts and some of the bizarre adaptations they have to spread themselves, as well as their role in health and disease. It is really only people with severely weakened immune systems, think HIV infections or cancer, who are at risk of infection by the sugar fungus. And pseudo-scientific claims from various health gurus notwithstanding, Candida yeasts are a benign part of our microbiome. Instead, Money highlights yeasts that are actual health risks.
The Rise of Yeast is a neat little book that elegantly covers a lot of ground. Money is no stranger to writing pop-science books about fungi and microbes. Some of the more outlandishly titled books he has previously written are The Amoeba in the Room, The Triumph of the Fungi, Carpet Monsters and Killer Spores, and Mr. Bloomfield's Orchard. He shows himself a gifted writer who keeps the matter light and infuses it with a touch of humour. Though not an all-encompassing deep history of baking or brewing, this book nevertheless gives many reasons why you should care more about little single-celled fungi.
Nicholas P. Money is Professor of Botany and Western Program Director at Miami University in Oxford, Ohio. He is an expert on fungal growth and reproduction. Nicholas has authored a number of popular science books that celebrate the diversity of the fungi and other microorganisms including Mr. Bloomfield's Orchard: The Mysterious World of Mushrooms, Molds, and Mycologists (2002), and The Amoeba in the Room: Lives of the Microbes (2014).