Listener Raffi is tired of his morning coffee going cold by the time he's ready to drink it. There are plenty of products out there promising to do a better job than Raffi's flask, and they come with a range of price tags. But how do they work and what is the ideal drinking temperature? Dr Michael de Podesta, a chartered physicist and measurements expert, has been looking into these very questions. He joins Greg and Raffi in the studio to run through his experiments - and explain how 'double walled technology' works and whether it's the answer to Raffi's prayers. Michael's even been trying out a high tech cup that claims to instantly cool your drink to a perfect drinking temperature - and keep it there for hours. Insulated cups also claim to be leak proof, durable and - in some cases - dishwasher proof. So joining them for this one is Kamisha Darroux, principal scientific adviser for Which? to talk about the tests they do and which other features are worth spending your money on. So are insulated coffee cups the best thing since sliced bread?PRESENTER: GREG FOOT
PRODUCER: TOM MOSELEY

Listener Raffi is tired of his morning coffee going cold by the time he's ready to drink it. There are plenty of products out there promising to do a better job than Raffi's flask, and they come with a range of price tags. But how do they work and what is the ideal drinking temperature? Dr Michael de Podesta, a chartered physicist and measurements expert, has been looking into these very questions. He joins Greg and Raffi in the studio to run through his experiments - and explain how 'double walled technology' works and whether it's the answer to Raffi's prayers. Michael's even been trying out a high tech cup that claims to instantly cool your drink to a perfect drinking temperature - and keep it there for hours. Insulated cups also claim to be leak proof, durable and - in some cases - dishwasher proof. So joining them for this one is Kamisha Darroux, principal scientific adviser for Which? to talk about the tests they do and which other features are worth spending your money on. So are insulated coffee cups the best thing since sliced bread? PRESENTER: GREG FOOT PRODUCER: TOM MOSELEY

Insulated Coffee Cups

While Sliced Bread takes a break we serve up Toast. A study of the spectacular failures of brands which had promised so much to consumers. In each episode, the presenter and BBC business journalist Sean Farrington examines one big idea. What did it promise? Why did people back it? Why did they get burnt? Some of the world’s most successful businesses have also brought us some of the world’s most remarkable failures. So, what led them to be toast? And what can we learn from their stories today? Sean unpicks all the early optimism, hype and ambition. He learns about the tremendous success of a brand before hearing how it faltered, with help from expert commentators and people who were directly involved. How do they view things now and what, if anything, could have been done differently? The self-made millionaire and serial entrepreneur, Sam White, is alongside him, analysing the missteps that changed a brand’s fortunes and reaching her own, often instructive, conclusions. From big tech to high street retail and, of course, food, Toast tackles the business ideas that, one way or another, ended up cooked. Sliced Bread returns for a new batch of investigations in January, 2026. In the new series, Greg Foot will investigate more of the latest so-called wonder products to find out whether they really are the best thing since sliced bread. In the meantime, Toast is available in the Sliced Bread feed on BBC Sounds. For this brand new series of Toast, episodes will be released weekly on Thursdays wherever you get your podcasts. But if you’re in the UK, you can listen to the latest episode on BBC Sounds first, a week earlier than anywhere else.Toast is a BBC Audio North production for BBC Radio 4.

Health & Fitness

While Sliced Bread takes a break we serve up Toast. A study of the spectacular failures of brands which had promised so much to consumers. In each episode, the presenter and BBC business journalist Sean Farrington examines one big idea. What did it promise? Why did people back it? Why did they get burnt? Some of the world’s most successful businesses have also brought us some of the world’s most remarkable failures. So, what led them to be toast? And what can we learn from their stories today? Sean unpicks all the early optimism, hype and ambition. He learns about the tremendous success of a brand before hearing how it faltered, with help from expert commentators and people who were directly involved. How do they view things now and what, if anything, could have been done differently? The self-made millionaire and serial entrepreneur, Sam White, is alongside him, analysing the missteps that changed a brand’s fortunes and reaching her own, often instructive, conclusions. From big tech to high street retail and, of course, food, Toast tackles the business ideas that, one way or another, ended up cooked. Sliced Bread returns for a new batch of investigations in January, 2026. In the new series, Greg Foot will investigate more of the latest so-called wonder products to find out whether they really are the best thing since sliced bread. In the meantime, Toast is available in the Sliced Bread feed on BBC Sounds. For this brand new series of Toast, episodes will be released weekly on Thursdays wherever you get your podcasts. But if you’re in the UK, you can listen to the latest episode on BBC Sounds first, a week earlier than anywhere else. Toast is a BBC Audio North production for BBC Radio 4.

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