Yeast: A guide for reluctant bakers
Yep, reluctant. That’s most of you – we know for a fact. (If we’re wrong, please hit us up with a barrage of comments on Insta and we will grovel. Promise. We’d love to be wrong here). Baking with yeast can seem daunting from the outside looking in. After all, that stuff is alive, and you can kill it (It’s actually a type of fungus). But the rewards of making your own yeasted goodies are worth any trepidation you may be feeling and we’re here to tell you that’s so easy to work with. Especially using today’s very stable instant dried yeast. With a little bit of knowledge and a dash of enthusiasm, you’ll be whipping up fluffy bread, rolls, sally lunns, brioche and pizza bases in no time. Let’s dive into the world of yeast, demystify its various iterations, understand how it works, and learn how to store it properly, shall we? Off we go!
What Exactly is Baking Yeast?
The use of yeast for baking (and brewing) dates back thousands of years. The ancient Egyptians used natural yeast, harvested from the environment, to ferment dough for bread. But it wasn't until the 19th century that yeast was better understood. In 1857, non other than everyone’s favourite pasteuriser, Louis Pasteur ,worked out that yeast is a living organism and is the thing that’s responsible for fermentation. His revelation led to more controlled and efficient methods of producing yeast for use in baking and brewing.
Forms of Baking Yeast
Yeast comes in a few different guises, each with its own characteristics:
Fresh Yeast (also known Compressed Yeast): This was the first type of commercial yeast, introduced in the late 19th century. It’s made by concentrating yeast cells from a liquid medium into a solid block. It’s soft, crumbly, and moist.
Usage: Fresh yeast needs to be dissolved in liquid before using; it’s preferred by professional bakers for its fast-acting properties (it works faster than dried yeast so proofing times are shorter), for going a consistent rise, and for better flavour development in the dough. It ferments in a way that gives a richer, more complex taste and, as it mixes more evenly through a dough, gives a superior texture and crumb structure. It can be hard for a home cook to source, however.
Shelf Life: Very short; it must be refrigerated and used within a couple of weeks.
Active Dry Yeast: Developed during WW2, when the need arose for a more shelf-stable yeast. It’s made by partially dehydrating yeast cells, which extends shelf life and makes storage and transportation easier. It is granular in form.
Usage: It needs to be dissolved and activated in warm water before use.
Shelf Life: Much longer than fresh, especially if stored in the fridge or freezer. Unopened, it can keep for 2 years; once opened, it’s best used within 10-12 months.
Instant Dry Yeast: Invented in the early 1970s. It’s made by further reducing the moisture in the yeast cells, and uses a special drying process to preserve the yeast’s viability and fermentation power. The granules are much finer than those of active dry yeast.
Usage: The big advantage of this form of yeast is it can be mixed directly into dry ingredients without the need for prior activation in warm liquid.
Shelf Life: Similar to active dry yeast.
How Yeast Works
The magic of yeast lies in its ability to ferment sugars in a dough – here’s a simple breakdown of the process:
Fermentation: Yeast consumes sugars and produces carbon dioxide and ethanol as by-products.
Carbon Dioxide: This gas gets trapped in the dough’s gluten network (the structure you build up when you knead a dough and that helps a loaf keep its shape during baking), causing it to expand and rise.
Ethanol: This evaporates during baking, leaving behind a light, airy texture and enhancing overall flavour.
Storing Yeast: Keep it Alive and Kicking
Proper storage is crucial to keeping your yeast active and effective:
Dry Yeast (Active Dry and Instant Yeast):
Store in a cool, dry place if unopened.
Once opened, keep it in an airtight container in the refrigerator or freezer.
Check the expiration date, but note that refrigerated yeast will last up to a year, and frozen yeast can be good for even longer. If it’s expired, it doesn’t hurt to try activating some in a little warm water to see if it’s still OK; you might be surprised at how long it will actually keep for.
Fresh Yeast:
Must be refrigerated.
Use within two weeks, even if the package hasn’t been opened.
Can be frozen, but it may lose some of its potency after thawing, so use it all within a month.
Tips for Reluctant Bakers
Start Simple: Begin with a straightforward recipe like a simple, plain bread. It’s a great confidence booster when you can turn out even a plain white loaf; from there, you’ll soon develop a ‘feel’ for dough and for the overall process. And you’ll start to understand it well enough to venture into more complicated yeasted goods, or even have the confidence to tweak a recipe and embellish it with additions, toppings. fillings etc.
Mind the Temperature: Yeast thrives in warmth but dies in excessive heat. Aim for a liquid temperature between 37°C and 43°C when activating dry yeast; essentially this is lukewarm, also described as ‘blood temperature’. Note that yeast won’t die due to cold, but will merely be inhibited and a dough will take longer to rise. Many bakers, for convenience and/or to deliberately develop flavour, rise their doughs slowly in the fridge overnight.
Be Patient: Good things take time! Allow your dough to rise properly for the best texture and flavour. Room temperature is best; you don’t need to put your dough in an overly warm place. Extra warmth will speed up the rising but a fast rise is not necessarily the best, as it can result in a less developed flavour and structure. (Note that when you’re reading bread recipes, ‘proofing’ simply means the process of resting the dough and letting it rise. It’s basically when the yeast is busy doing it’s fermenting thing, and it’s a crucial step in bread making. Usually there are two proofings; an initial one after kneading, during which the dough doubles in size, and another after shaping, when it will increase in bulk but not necessarily double.)
Experiment and Have Fun: Baking is as much an art as it is a science. Don’t be afraid to experiment with flavours and shapes; for example, divide a batch of dough into small balls to make buns instead of baking a whole loaf. Add raisins, citrus zest, extra sugar and spices to a plain dough for a sweet fruit bread, or add snipped fresh herbs and olives, or loads of grated cheese, for a savoury flavour.