A machine similar to the ones used to make frozen yogurt freezes the head of the beer into something that looks like a serving of soft vanilla ice cream, helping to keep pints frosty cold even as the mercury tops 40 Celsius (104 Fahrenheit).

Made of pure beer - no ice or water is added - the frozen froth keeps the beer chilled for at least 30 minutes, well over the average of 22 minutes to finish a pint, as a Kirin survey found.

"We thought people won't spend more than five minutes on a pint of beer but apparently not," said Kunihiko Kadota, Kirin's marketing brand manager for the "frozen draft" campaign.

"Women and young drinkers spend much more time to drink it all up, and they like the idea the beer doesn't get warm towards the end."

The beer boffins came up with the idea as part of an effort to stem a decline in sales as the younger generation switches to more fashionable wine and cocktails.

The draft with the icy head is available at more than 200 outlets across Japan, and the brewer aims to set up 1,000 machines in restaurants nationwide. Interest is also brewing in the United States and Europe, Kadota said.

"The love for ice-cold beer is universal."

(Reporting by Leika Kihara; Editing by Elaine Lies and Robert Birsel)

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