the drunken botanist

That’s the title of one of the books I’m reading at the moment: The Drunken Botanist, by Amy Stewart. (I do not know any drunken botanists!) Contrary to any expectations engendered by the title, the book is a thoroughly engaging wander through botany, history, & a little bar-tending (although, now that I look at the recipes, there are quite a few of them!) – in the sense that it includes recipes for a range of cocktails where at least some of the ingredients are derived from plants. 

But be warned. As the author points out, just because many of these ingredients come from plants, doesn’t mean you can just set to it & start brewing up a storm. She notes

Do remember that plants employ powerful chemicals as defenses against the very thing you want to do to them, which is to pluck them from the ground and devour them…

It is also important to note that distillers can use sophisticated equipment to extract flavourings from a plant and leave the more harmful molecules behind, but an amateur soaking a handful of leaves in vodka has no such control… Just because a distiller can work with them safely doesn’t mean you can, too.

Which is why those consuming ‘moonshine’ may well be at risk of more than a simple hangover. 

Anyway, I am finding this book to be a fascinating ramble down a whole range of information by-ways. I’ve learned, for example, that the agave – whence come tequila & mezcal – is actually related to asparagus, & that it’s possible to persuade the plant to produce up to 250 gallons (more than 1000 litres) of sap over a period of several months, by cutting and wounding the flower stalk just as it begins to grow. (In this, an agave plant outstrips the annual production of a sugar maple tree – but the tree has the advantage that it lives to flow another year. The agave eventually dies, exhausted.) This liquid is fermented very quickly by ‘wild’ microbes, & – being an innocent in these things – I thought that would be distilled to produce tequila. But I was wrong – this spirit’s produced from a base of roasted agave hearts. And while you might be thinking of a metal or glass still, it seems in Mexico they used to use a hollow tree trunk as the basis of the still!

Apparently the worm is there as a marketing ploy…

So, there’s snippets of genetics, & palaeontology, & chemistry, & botany, & anthropology – it really is an interesting book. And Stewart has the ability to turn some lovely phrases. I’ll leave you with the following, which I love & will be using tomorrow when discussing cellular respiration in class:

The science of fermentation is wonderfully simple. Yeasts eat sugar. They leave behind two waste products, ethyl alcohol and carbon dioxide. If we were being honest, we would admit that what a liquor store sells is, chemically speaking, little more than the litter boxes of millions of domesticated yeast organisms, wrapped up in pretty bottles with fancy price tags.

A.Stewart (2012) The Drunken Botanist: the plants that create the world’s great drinks. Algonquin Books of Chapel Hill. ISBN 978-1-61620-046-6