Chocolate

 By the end of the 19th century, a wealthy middle class had been created by the Industrial Revolution. York's chocolatiers set out to develop a high-end product to appeal to this lucrative new market.

A company called Terry's led the way using shiny, tempered chocolate to make extravagant boxes of truffles.

In Victorian times chocolates became very sophisticated and expensive.

This box of chocolates cost 24 shillings in 1900 and the average weekly wage for a man was 18 shillings, this was something incredibly special. giving this size box to a lady was the equivalent of a marriage proposal at the time. Victorian etiquette demanded that a single woman should never accept choclates from a man she was related or engaged to.

Rowntree's introduced pensions, eight-hour days and free health care for their factory staff.

In the 1930s a Rowntree's worker is believed to have put a note in the company's suggestion box asking the bosses to invent a cheap chocolate bar which a man could take to work in his packed lunch. Chocolate was still expensive so the company's development team set about trying to find ways to make it cheaper. The development was done by hand in the Rowntree's research kitchen.

Originally known as the Chocolate Crisp, today it's known as a Kit Kat. The first thing that brought the price down was the use of milk chocolate. Originally invented in 1875, it was cheaper to produce than pure chocolate because the cocoa content was lower. What's more, the addition of milk products made it popular because it was sweeter and more creamy. The third way in cutting the price was adding a wafer, a sweet, cheap biscuit baked in sheets.

In the York site they produce around four million Kit Kats a day. The York factory is one of 14 Kit Kat factories around the world. Today's production line churns out up to 160,000 an hour. The Kit Kat is the most successful chocolate bar of all time.