Dinner by Heston Blumenthal proving so popular that by November 2011, some 900 were being sold per week and the restaurant was aiming to increase production to be able to supply up to 1200 a week. During the Christmas period, the Meat Fruit is decorated to appear like a plum rather than a mandarin to accord with the holiday season. The ice cream trolley holds a contraption created by Blumenthal and his team, and constructed from Corian by Mike Smith Studio at a cost of £25,000. Powered by a hand crank, it mixes custard and liquid nitrogen to create instant ice cream at the
Ice cream maker firm consistency. Some machines—such as certain lower-priced countertop models—require the resulting mixture to be frozen for additional time after churning is complete. Nancy Johnson patented the first hand-cranked model in 1843. She then sold the patent to William Young, who marketed the machine as the "Johnson Patent Ice-Cream Freezer". Hand-cranked machines' ice and salt mixture must be replenished to make a new batch of ice cream. Usually, rock salt is used. The salt causes the ice to melt and lowers the temperature in the process, below fresh water freezing, but the water does not freeze due to the salt content.