This syrup is not to be confused with the dark heavy malt syrup used by brewers and bakers. It is easily available in Korean markets, in both clear and amber varieties. It has the same consistency as honey, and the amber has a similar, but much lighter, flavor. They are about 1/3 as sweet as honey or sugar. Even the amber has a lighter malt flavor than Ssalyeot (rice syrup) which is 100% malted rice.
Subst: The closest American substitute is Corn Syrup. Not the "High Fructose" variety, but plain corn syrup, like Karo Light. The malt flavor of the amber malt syrup won't be there, and the Corn Syrup is significantly sweeter, but it will work for swetness and glaze. Corn syrup is almost entirely Glucose, which is not as sweet as Sucrose. Maltose is two glucose molecules bound together and is less sweet than glucose.
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This is a somewhat confusing ingredient. In Korea it was originally made from Barley Malt, but today, the clear Mulyeot is often just corn syrup (rather unauthentic, that), while the amber may be made using some malted rice, but is much lighter in color than Ssalyeot (rice syrup) which is made from 100% malted rice. Koreans often use the term "Mulyeot" when referring to Ssalyeot. The word Mulyeot simply means "liquid candy". Korean cookbooks in English, especially older ones, presume you can't get this ingredient, and often list "honey" or "sugar" instead.
This is a fairly common ingredient in Korean cooking, and similar products are used in Japan, and in China, particularly for creating the glaze on Peking Duck. Adherence to tradition may vary greatly from brand to brand. The photo sample, distributed by Jayone Foods Inc. of Paramount, California, was purchased from a Korean market in Los Angeles at about 2015 US $3.49 for 1.54 pounds. It boasts "No Preservatives, MSG or Artificial Color". Ingred: Cornstarch, Water, Malt. Enzymes in the Malt digest the Cornstarch into maltose. This company's clear version has the same ingredients, but the malt is probably not as natural as for the dark.
Cooking: This syrup is often mixed with Soy Sauce and other seasonings used in stir fries and coatings for meat. It provides a light sweetening and an attractive glaze.
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