High maltose corn syrup
High maltose corn syrup is a food additive used as a sweetener and preservative. The majority sugar is maltose. It is less sweet than high fructose corn syrup, and contains little to no fructose. It is sweet enough to be useful as a sweetener in commercial food production, however. To be given the label "high," the syrup must contain at least 50% maltose. Typically, it contains 40–50% maltose, though some have as high as 70%.
By using β-amylase or fungal α-amylase, glucose syrups containing over 50% maltose, or even over 70% maltose (extra-high-maltose syrup) can be produced.p. 465 This is possible because these enzymes remove two glucose units (i.e. one maltose molecule) at a time from the end of the starch molecule.
High-maltose glucose syrup is used as a substitute for normal glucose syrup in the production of hard candy: at a given moisture level and temperature, a maltose solution has a lower viscosity than a glucose solution, but will still set to a hard product. Maltose is also less humectant than glucose, so that candy produced with high-maltose syrup will not become sticky as easily as candy produced with a standard glucose syrup.p. 81
Since maltose has a low freezing point, HMCS is useful in frozen desserts. It is also used in brewing, because it has a balanced fermentability, can be added at high concentrations to the wort kettle, increasing throughput, and reduces haze caused by varying malt quality. Another of HMCS's uses is to preserve food. According to the Center for Science in the Public Interest, HMCS preserves food by inhibiting fermentation and bacterial growth.
Health effects 
In recent years, HMCS has seen an increase in use as a food additive due to the negative reputation of HFCS, as well as the absence of fructose, which is the source of the concern about the health effects of high-fructose corn syrup.
High maltose syrups produced from corn are gluten-free, but certain syrups produced from wheat or barley may contain small amounts of gluten. It is unclear whether this can have significant effects in celiac disease.
As a sugar, maltose can have harmful dental effects if teeth are not cleaned properly following consumption.
- Y.H. Hui, ed. (2006). Bakery products : science and technology (1st ed. ed.). Ames (Iowa): Blackwell. ISBN 978-0-8138-0187-2.
- Hull, Peter (2010). Glucose syrups : technology and applications. Chichester, U.K.: Wiley-Blackwell Pub. p. 80. ISBN 978-1-4051-7556-2.
- Panesar, Parmjit S. (2010). Enzymes in food processing : fundamentals and potential applications. [S.l.]: I K International. p. 184. ISBN 93-8002-633-1.
- McPherson, Andrew. Ingredient interactions: effects on food quality. p. 172.
- Hui, Yiu H. Handbook of food science, technology, and engineering, Volume 4. p. xxiv.
- Sang Ki Rhee; Alexander Steinbüchel (2005). Polysaccharides and Polyamides in the Food Industry: Properties, Production, and Patents. Weinheim: Wiley-VCH. ISBN 3-527-31345-1.
- Peter Hull (2010). Glucose Syrups: Technology and Applications. Wiley-Blackwell. ISBN 1-4051-7556-7.
- "What Is High Maltose Corn Syrup?". Retrieved 14 August 2011.
- "What Is High Maltose Corn Syrup?". The Healthy Apron.
- Scientific Panel on Dietetic Products, Nutrition and Allergies (15 February 2007). "Opinion of the Scientific Panel on Dietetic Products, Nutrition and Allergies on a request from the Commission related to a notification from Finnsugar Ltd on glucose syrups produced from barley starch pursuant to Article 6, paragraph 11 of Directive 2000/13/EC". The EFSA Journal 456: 1–6.
- Iametti, Stefania; Cappelletti, Chiara, Oldani, Antonio, Scafuri, Laura, Bonomi, Francesco (1 January 2004). "Improved Protocols for ELISA Determination of Gliadin in Glucose Syrups". Cereal Chemistry 81 (1): 15–18. doi:10.1094/CCHEM.2004.81.1.15.