| 摘要 |
Malt culms or malt culm extracts that are free from bitter principles are obtained by treating the culms with an aqueous solution containing at least 25% by weight of a mono- or disaccharide. The treatment is performed by the percolation of 30-50% aqueous solutions of cane or beet sugar, maltose, glucose or invert sugar, or 75-80% brewer's sugar syrup, for 2 hours or more at a temperature not exceeding 50 DEG C. According to an Example, 4Kg. culms are submitted to extraction with 16 litres of a 40% solution of brewer's sugar in a percolator. Second and third passes are performed each with 16 litres of water. The extracts from the first and second passes are combined, filtered and concentrated in a vacuum under nitrogen to a syrup of acceptable taste which is free from bitter principles and rich in vitamins. The aqueous extract from the third pass is thickened with brewer's sugar to a sugar content of 40% and used for the next extraction or percolation of a fresh batch of culms. It is stated that the extraction of the culms with a sugar solution gives higher yields of vitamins in the extract than when extracting with water or with a 0.5% aqueous solution of citric acid. The culms from which the bitter principles have been removed by the extraction have a nutty taste which they retain after having been gently dried in air or in a vacuum. |
