From bread to delicate omelettes and immunosuppressive drugs. Julia McLean takes us on a journey through the UK, France and Italy as she explores the many uses of mold and fungi.
There were several things I learnt about mushrooms this year which I thought were fascinating – the most striking is that they are a different animal than I had previously thought and biologically are classified as a kingdom separate from plants, animals and bacteria. They are a species unto themselves but resemble animals more than plants.
We usually are vaguely aware of the fact that moulds are a type of fungus but some people are not aware that yeast is. Yeast is a most important micro-organism causing several types of fermentation which allow humans to convert basic nutrients into further forms of food. Saccharomyces cerevisiae, a single celled fungus is used to make bread and other wheat based products such as pizza and dumplings. If you haven’t got any yeast to make your bread you can beat up some flour and water into a runny paste and leave it in a warm place, stirring from time to time. Yeast exists in most environments so the mixture will acquire yeast from the air and can be used as a starter for your bread in a few days. Feed it with a bit of sugar to help it develop. The name of this yeast also tells us that it is used in beer making and, of course, for other alcohols. We couldn’t make our cider without it. There are different yeasts for the brewing of soy sauce, sake (the white firey liquid beloved of the Japanese!) and the preparation of miso – basic Japanese soup stock.
Torula yeast is produced from wood sugars, as a by product of paper production. It is pasteurized and spray-dried to produce a fine, light greyish-brown powder with a slightly yeasty odour and gentle, slightly meaty taste and is widely used as a flavouring in processed foods and pet foods. Quorn, high in protein and therefore a staple of vegetarian diets is made from the fusarium venenatum fungus, discovered in the UK in the 60’s.
Fungus, in the form of mushrooms and truffles have long been used as a direct source of food. Autumn is the traditional truffles hunting season in both Italy and France. In Perigord – South-Western France, pigs are generally used for truffle hunting but I believe the hunters are changing over to specially trained dogs like the Italians. There are both white and black truffles.
The ‘white truffle’ or “Alba madonna” comes from the Langhe area of the Piedmont region in northern Italy and, most famously, in the countryside around the city of Alba. There are other regions of Italy where truffles can be found but none is as prized as the Alba. You should go to the Fiera del Tartufo ( truffle fair) held in October/November in Alba. Truffles can alsobe found in Croatia but the Piedmont truffle is the most sought after and can fetch up to $4500 per kilo.
The ‘black truffle’ comes from Perigord and grows mainly under oaks or hazelnuts. The markets are held in January in Richerenches (in the Vaucluse) and Lalbenque (in Quercy). David Lebovitz on his site says ‘Interestingly, the appeal of truffles isn’t so much their taste. It’s their aroma that makes you wilt with pleasure. As you might know, a good portion of taste relates to the scent of foods’. In 2009 black truffles sold for $1000 a kilo on the market but $3000retail. If you are interested in cooking with truffles, let me recommend the ‘truffle-and truffe’ website. I have occasionally eaten them in delicate omelettes and as thin slices under the skin of a roast chicken. They are often shaved and served in a creamy sauce with tagliatelle.
Fungi are amazing in other ways too and can either cause diseases (Candida Albicans, more commonly known as thrush) or combat them. Metabolites, produced by many fungi, are major sources of pharmacologically active drugs. Particularly important are the antibiotics, including penicillins. Although penicillin G and other naturally occurring antibiotics have narrow spectrums of biological activity, a wide range of others can be produced by the chemical modification of naturally occurring penicillins. Other antibiotics produced by fungi include: ciclosporin, commonly used as an immunosuppressant during transplant surgery; and fusidic acid, used to help control infection from methicillin-resistant Staphylococcus Aureus bacteria.
Widespread use of these antibiotics for the treatment of bacterial diseases, such as tuberculosis, syphilis, leprosy, and many others began in the early 20th century and continues to play a major part in anti-bacterial chemotherapy. When normal, protective bacteria are eradicated by antibiotics or by immunosuppressive drugs, for example, yeasts can multiply and invade tissues. This happens with Candida infections. When too strong doses of antibiotics destroy intestinal flora, they can cause chronic diarrhoea. Doctors often recommend acidophilus tablets to re seed the intestines.
Fungi can be found all over the world and grow in very different habitats, including extreme environments such as deserts or areas with high salt concentrations as well as in deep sea sediments. Very little is really known of the true biodiversity of Kingdom Fungi. Only about 5% of a possible 1.5 million species have been formally classified.
Further Reading and Recipes:
Wild Mushroom Recipes
All photos courtesy of Julia McLean