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1. Many scientists of the past tried to find out what foods consist of. 2. For a long time chemists studied how food was digested by a human body. 3. Everybody is sure that food is essential to the nutrition of any form of life. 4. People do not know exactly when wheat cultivation began. 5. You should know that dough rises in the trough to several times its original size. 6. Don’t forget that dough troughs are wheeled into the fermentation room. 7. A technologist experienced in breadmaking immediately understands when dough becomes mature. 8. Do you know where moulded dough pieces are subjected to final proofing. 9. The tests were carried out to see what occurs when bread is wrapped without cooling. 10. It is interesting who will carry out these tests. 11. In their experiment they must explain why biological reactions are accelerated in the dough loaf during baking. 12. Close control shows that the crust of baked bread changes due to temperature rise in the oven. 13. It is known that bread cooling is carried out in two ways.