evaporated by boiling, until the final desired water content of the syrup is achieved. Brown rice syrup generated by this process is protein, fibre (hemicellulose) and lipid free and usually consists of 65–85% maltose, 10–15% maltotriose, 5–20% dextrins and only 2–3% glucose. The final carbohydrate mix of brown rice syrups can be controlled and adjusted by the manufacturer. The enzymes used in the liquefaction step are usually alpha-amylases derived from bacterial or fungal bioreactors (Bacillus species or Aspergillus species are the most commonly used microbe engines in the bioreactors). These convert starch into dextrins of various molecular sizes and the modified starch end product is usually given an appropriate DE (dextrose equivalent) rating to signify the degree of starch conversion and the amount of reducing sugars produced in the process. The enzymes used in the saccharification step are the amylolytic enzyme, beta-amylase (usually derived from Bacillus species) and the debranching enzyme, pullulanase (derived from Aerobacter species). These convert the dextrinised starch into simple carbohydrates (sugars) and lower molecular weight dextrins. The modern industrial production of brown rice syrup does not involve the use of synthetic chemicals in the modification of flour and starch. The enzymes added in processing are naturally derived from organic bioreactors using methods similar to the creation of antibiotics. Brown rice syrup is readily available in most western Chinese grocery stores as maltose or maltose syrup, in reference to the high maltose content of the sweetener. This product is almost always produced by the industrialized method. Rice syrup has a shelf life of about a year, and once opened, should be stored in a cool, dry place. Brown rice syrup is the sweetener found in some drinks, such as rice milk. Brown rice syrup is produced on a commercial scale by several companies in the United States, Europe, and Asia. Glycemic index Brown rice syrup (BRS) has a glycemic index (GI) of 98 which is higher than table sugar (65) and about the same as glucose (100), the sugar used as the baseline to measure other foods against. Toxic impurities Brown rice syrup and products containing it were found in a 2012 study to contain significant levels of arsenic, which is toxic to humans. This is presumably due to the high prevalence of arsenic in rice. The authors recommended that regulators establish legal limits for arsenic levels in food, particularly in infant and toddler formulas. See also