| 摘要 |
<p>The novel tea bag is composed of sheet materials impregnated with acidic substances. The acidic substance is citric acid, malic acid, glutaric acid, tartaric acid, succinic acid, potassium dihydrogen phosphate and/or monosodium hydrogen sulphate and is present in an amount of 0.03 to 0.5 mg/cm<2>. The sheet material is generally paper. On contact with water, an acidic reaction is caused therein. The colour of aqueous infusions, which are produced with these tea bags, is considerably better than with the previous tea bags. The sheet material can be impregnated by dipping conventional tea bag paper into an aqueous solution of the acidic substance or spraying it with this and then drying it.</p> |
