Glucose syrup

[5] Depending on the method used to hydrolyse the starch and on the extent to which the hydrolysis reaction has been allowed to proceed, different grades of glucose syrup are produced, which have different characteristics and uses.

The original glucose syrups were manufactured by acid hydrolysis of corn starch at high temperature and pressure.

Higher DE syrups made by acid hydrolysis tend to have a bitter taste and a dark colour, due to the production of hydroxymethylfurfural and other byproducts.[1]p.

26 This type of product is now manufactured using a continuous converting process[6] and is still widely used due to the low cost of acid hydrolysis.

[6] A typical confectioner's syrup contains 19% glucose, 14% maltose, 11% maltotriose and 56% higher molecular mass carbohydrates.[7]p.

Protein produces off-flavours and colours due to the Maillard reaction, and fibre is insoluble and has to be removed to allow the starch to become hydrated.

Formerly, glucose syrup was only produced by combining corn starch with dilute hydrochloric acid, and then heating the mixture under pressure.

Currently, glucose syrup is mainly produced by first adding the enzyme α-amylase to a mixture of corn starch and water.

[8][9] After hydrolysis, the dilute syrup can be passed through columns to remove impurities, improving its colour and stability.

[10] Glucose syrup was the primary corn sweetener in the United States prior to the expanded use of HFCS production.