How many grams in a cup? How to convert US recipes to metric

<span>Photograph: Grace Cary/Getty Images</span>
Photograph: Grace Cary/Getty Images

Can you reliably convert American recipes to UK measurements?
Joe, Margate
“It really depends on the kind of recipe you’re talking about,” says the American food writer Sarah Chamberlain, who has converted the likes of Diana Henry’s From the Oven to the Table for US cooks. “People in the UK get caught up on, ‘Oh my god, you use cups!’, but with all liquid measurements, it’s a pretty straightforward conversion: one cup equals 240ml, which you can easily divide, so half a cup is 120ml.” In some cases, you can even “fudge it and say 250ml, because 10ml either way isn’t going to make a huge difference”, but that really boils down to what it is you’re making.

Stews and curries, say, are far more forgiving than baking, which Chamberlain brands “another adventure entirely”. Here, you simply have to look up the conversions, which is what the internet is for: “The information is commonly available online,” Chamberlain says, “but if you’re baking or measuring solids, just buy a set of cups.” Ingredient weights differ – a cup of flour, for example, is 125g, while the same of sugar is 200g – so this will just make your life easier.

That said, Nik Sharma, the California-based author of Veg-table, published in October, says he still struggles with cups. “Weights are the safer measurement,” he says. “With a cup of chocolate chips, for example, there’s going to be so much space between each one, while with flour it depends on how you got it out of the bag and level it.” Not all cups are created equal, either: “They can differ, so whenever I buy a new set, I always make sure it measures 240ml water.”

Then there’s butter, which in the US is measured in sticks (or tablespoons). “The standard size of a stick is 113g,” says Chamberlain, although she often rounds that up to 125g – “Who’s really going to care about 12g more butter?” In short: “Think of a standard 250g UK block as two sticks plus a bit extra, and each stick is eight tablespoons.” If, however, Joe finds himself at a loss, Chamberlain suggests heading to the website of a US supermarket: “Look up a product and it will state serving size in cups and grams.”

Ingredients don’t always translate, though. “The cuts of meat in the US and UK are different,” Chamberlain notes. “Americans don’t have back bacon, say, because they cut a pig differently.” Size matters, too: “A medium egg in the UK is a large egg in America, which is counterintuitive; conversely, an American onion is generally 50% bigger than one in the UK.”

This proved a problem when Sharma was writing his latest book: “Not only is there a difference in the weight of vegetables at the market versus what’s available in stores, but the US Department of Agriculture classifies vegetables based on dimension, not weight.” So, you’ll just have to use your common sense: “Think about what a sensible amount would be to put in,” Chamberlain says. “Plus, the rule about reading a recipe closely before you start applies doubly so here.”

Some American cooks are, however, moving into metric. “If you want to bake an American-style cake,” Chamberlain says, “look to the likes of Joanne Chang, because she does the conversions for you. Things are slowly changing, with recipes crossing oceans.” Australia, meanwhile, has its own system altogether, but that’s a discussion for another day …

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