The simplest product form of biscuits is a mixture of flour and water, which was found in ancient Egyptian tombs around 4000 BC. The truly shaped biscuits can be traced back to Persia in the 7th century, when the sugar-making technology was just developed and was widely used because of biscuits. Until the tenth century, with the Muslim conquest of Spain, biscuits spread to Europe, and then spread in various Christian countries. By the14th century, biscuits had become the favorite snack of all Europeans, and the fragrance of biscuits spread from the royal kitchen to the streets where civilians lived. Modern biscuit industry began in Britain in the19th century because of advanced navigation technology. During the long voyage, bread is not suitable as reserve grain because of its high water content (35%-40%), so a kind of bread with low water content-biscuit was invented. The main raw material of biscuits is wheat flour, and then sugar, oil, eggs, dairy products and other accessories are added. According to the different formula and production technology, sweet biscuits can be divided into two categories: tough biscuits and crisp biscuits.