Why does sourdough bread from California taste different to UK loaves? (2024)
San Francisco sourdough bread tastes completely different to sourdough from the UK. Are UK yeasts different from Californian ones or is this due to the bread-making process?
Andrew Farrer London, UK
Sourdough is made using a starter culture created by exposing flour and water to the air to “infect” the mixture with natural yeasts.
I noticed that when I moved just 5 kilometres north from central London, it led to changes in my existing starter within a week or so: it became more sour and vigorous, meaning the dough rose more quickly. The place I now live is about 60 metres higher, so maybe that makes a difference. The starter also became more vigorous when I took it to France.
I suspect that if you brought a San Francisco starter to London, it would quickly become infected with London yeast and take on the characteristics of a London starter.
It depends what is meant by “San Francisco sourdough” and “sourdough from the UK”, as there is no standard definition for either. However, San Francisco sourdough tends to be more sour, aerated and chewy than other types.
All sourdough bread is leavened with a starter prepared by spontaneous fermentation of a mixture of flour and water. Large-scale commercial sourdough usually has extra yeast added to speed up production. So if we consider only artisanal and home-baked sourdough, then there are four main reasons for the differences between UK and San Fransisco loaves: the microbes in the starter, the flour, the recipe and the process.
Sourdough’s sourness is due to lactic and acetic acid made by bacteria, mainly from the Lactobacillus genus, while yeasts produce carbon dioxide gas that aerates the loaf. The microbes create metabolites responsible for flavour, and originate from the starter, the environment, the hands of the baker, the equipment and the flour. The flavour of San Francisco sourdough is often wrongly attributed to Lactobacillus sanfranciscensis, but this species is abundant in starters around the world.
The microorganisms in flour depend on its type, and the manner and location in which the grain was grown and processed. Organic wholemeal flour has a particularly abundant supply of them. The flour’s protein content plays an important role in the loaf’s texture and its ability to hold gas bubbles. The amount of water is crucial too, as an elastic dough is necessary to allow expansion when gas is made.
Finally, the method for mixing and treating the ingredients also affects flavour and texture. Sourdough bread requires a slow fermentation over one to four days. This, together with the temperature at which the dough is held, affects which microorganisms thrive. It is therefore unsurprising that sourdough is different depending on where it is made and by whom, resulting in variations in bread characteristics.
To answer this question – or ask a new one – email lastword@newscientist.com.
Questions should be scientific enquiries about everyday phenomena, and both questions and answers should be concise. We reserve the right to edit items for clarity and style. Please include a postal address, daytime telephone number and email address.
New Scientist Ltd retains total editorial control over the published content and reserves all rights to reuse question and answer material that has been submitted by readers in any medium or in any format.
You can also submit answers by post to: The Last Word, New Scientist, 25 Bedford Street, London WC2E 9ES.
Sourdough bread requires a slow fermentation over one to four days.This, together with the temperature at which the dough is held, affects which microorganisms thrive. It is therefore unsurprising that sourdough is different depending on where it is made and by whom, resulting in variations in bread characteristics.
Some say the foggy climate gives San Francisco's sourdough bread a special bounce, and others say it's a specific local strain of yeast that gives the characteristic flavor. That bounce and flavor are notes that pair perfectly with a California Chardonnay or Chenin Blanc.
As it happens, the reason why sourdough's taste can change has to do with each sourdough's terroir. A terroir is just a fancy way of referring to the environment in which the sourdough is produced and refers to things like temperature, air, and more.
The sourdough craze spread like wildfire, and today there is a huge number of artisanal bakeries that sell sourdough bread all around the San Francisco Bay Area.
San Francisco sourdough bread is perhaps the most famous type of sourdough bread. It is characterized by its tangy flavor, chewy texture, and slightly sour aroma. The unique flavor comes from the use of a specific strain of wild yeast and bacteria that is found only in the San Francisco area.
Although you can make sourdough anywhere, the sourdough in San Francisco, California is world famous famous for its special unique flavor. Some of the flavor of California sourdough comes from lactic acid bacteria.
It's richer in nutrients, less likely to spike your blood sugar, contains lower amounts of gluten, and is generally easier to digest than bread made with baker's yeast. Sourdough bread is one of my favorite types of bread. Not only do I find it tastier than conventional bread, but it's also arguably more nutritious.
The key to sourdough bread tasting the way it does is the strain of bacteria, lactobacillus sanfranciscensis. And if that name looks like it has ties to San Francisco, it does. "This special strain of lactic acid bacteria thrives in our salty, cold environment," says Kosoy.
Somehow, the bread tasted tangier and more flavourful than it did elsewhere, and thus San Francisco sourdough was born. More than 170 years later, San Francisco is synonymous with sourdough bread.
Despite the fact that traditional sourdough ingredients are flour, water, and salt, many store-bought versions include added yeast, ascorbic acid, vinegar, and oil. So, although many grocery stores may carry bread labeled “sourdough”, more often than not they are in fact fake sourdough.
When choosing a sourdough loaf, look for ones that have whole wheat, spelt or rye, Rizzo adds. Some studies suggest that Einkhorn wheat, a type of "ancient grain," may offer more nutritional benefits. When comparing nutrition labels, try to opt for the one with fewer ingredients and less sodium and sugar.
As the city's bread fame grew, a rumor circulated that the strain of bacteria (found in the starters' wild yeasts) responsible for San Francisco sourdough's distinctly tart flavor simply could not be produced anywhere else.
The yeast responsible for most of the sour tones in this bread come from L.sanfranciscensis. Although it is likely any starter will contain some of this wonderful yeast already, we use our San Francisco sourdough starter which is already very high in this naturally found, heat-loving yeast.
Springy texture, gently tangy, pleasantly chewy — Trader Joe's sourdough loaf remains a favorite among shoppers. The versatile sandwich bread is a blank canvas for grilled cheese enthusiasts and fancy toast creators. The soft bread holds up against soggy sandwich fillings and caramelizes evenly when exposed to heat.
Sourdough bread traces its origins to ancient Egypt and is common in parts of Europe. It became a staple in San Francisco during the California Gold Rush of 1849.
Different bacteria make different sour flavors; San Francisco is awash in local bacteria species that make its sourdough bread famous. So sourness per se in some ryes and many other breads is quite desirable."
Introduction: My name is Pres. Lawanda Wiegand, I am a inquisitive, helpful, glamorous, cheerful, open, clever, innocent person who loves writing and wants to share my knowledge and understanding with you.
We notice you're using an ad blocker
Without advertising income, we can't keep making this site awesome for you.
