Modern ketchup began in the early 20th century. The direct cause of its appearance was the discussion on the use of sodium benzoate. The father of the U.S. Food and Drug Administration, Harvey Weili, doubted the safety of benzoic acid. So entrepreneurs, especially H. J. Heinz (founder of Heinz Foods), began looking for substances that could be used to replace benzoic acid.
The previous ketchup was very dilute due to the use of immature tomatoes with less pectin content. The tomato sauce at the time contained less vinegar than it does today. By selecting ripe tomato as the raw material, benzoic acid is not used in tomato sauce, and its taste is not inferior to that of the early tomato sauce. Some experts believe that this change in raw materials not only removes the use of benzoic acid, but also changes its taste, and it is this change in taste that makes it a widely used condiment today.
The previous ketchup has two flavors: bitter and salty. However, tomato ketchup also gained umami taste when switched to mature tomatoes and added more tomato pulp. It also gets sour and spicy by adding more vinegar. Without benzoic acid it doubles its sweetness. The blending of these five flavors makes ketchup very delicious.
In the past, tomato ketchup was made using fresh tomatoes. The tomato was transformed into a very viscous tomato paste by vacuum evaporation after harvest. This tomato paste can be stored at room temperature for a long time, so that it can be used to make ketchup all year round.
Past tomato ketchup is generally packed in glass jars that effectively protect ketchup from drying and oxidation, but because ketchup is more viscous, it is not easy to pour out of glass jars. The newly introduced polyethylene bottle allows people to easily extrude ketchup. Most ketchups today are packed in polyethylene bottles.