关键词: 速溶茶, 速溶茶, 酯型儿茶素, EGCG, 加工原料

Abstract: Due to the low content of soil organic matter (SOM) on soils in the loess plateau, the classical method for determining SOM seemed to be inefficient, time- consuming and non economic. Totally, 69 soil samples with SOM ranging from 2.0 to 30 g/kg had been selected to test modification of classical method, which reduced 50% of digestion solution (K₂Cr₂O₇-H₂SO₄) and kept other procedures unchanged. The results showed that SOM contents determined by modified method were comparable with those determined by classical method when soils had content of soil organic matter below 8.7 g/kg. With SOM content increase, differences of SOM content determined by two methods became larger and larger, and significant lower values determined by modified method than classical method were observed when soils had the content of soil organic matter above 15.2 g/kg. It was concluded that modified method could save time, more efficient and economic for measuring soils with low SOM contents, especially below 8.7 g/kg.