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Chewing gum[knows|is known|has been known|has known]from ancient times. The first people who tried it were ancient Greeks. They chewed resin from trees. The Mayans also made gum from a sapodilla tree and called it 'Chicle'.The next step for the chewing gum was in 1869 when it [patents|had patented|had been patented|was patented] by an Ohio dentist Amos Tyler. He never used chewing gum commercially. In 1928, another American Walter Diemer accidentally[invented|was invented|had invented|had been invented] bubble gum that was not sticky. Since then bubble gum has become known all over the world. Traditionally, bubble gum was made from a tree resin, but nowaday it[is made|make|makes|was made] of synthetic materials.

So, what is the process of production? The first step is when the gum base is put into a mixer. Then colour and flavouring are added to the base later. While the mass[was mixed|mixes|is being mixed|is mixing], they pour some glucose syrup to make it sweet and soft. Some time later a powdered sweetener is added into the mass, too. All ingredients are mixed together for about 20 minutes for perfect blending. When the mass is ready, it is put into a special machine. It [is squeezed|squeezes|squeeze|has squeezed] the mixture into long strips. At this stage the gum is warm and sticky, that's why it needs to be cooled down for 15 minutes. When the gum is cold enough, it is bite-size cut and packaged with help of machines. The machine[is produced|produces|produce|has produced] 900 pieces of the gum per minute. The last stage is packaging into tubs. The pieces of gum are weighed in right amounts for each tub. Then the tubs [seal|are sealed|are sealing|had been sealing] with plastic. It is necessary to keep the gums fresh.