迅速透析を用いた食品中のステビオシドおよびレバウジオシドA分析法

摘要

食品中のステビオシドおよびレバウジオシドAについて,迅速分析法を開発した.透析効率を上げるため,透析液に30%メタノールを用い,試料10g,透析の総量100mLに対して有効長30cmの透析チューブを使用した.さらに,透析時に50℃で加温しながら振とうすることにより,従来48〜72時間要した透析時間を2時間に短縮した.得られた透析後の外液をC18固相抽出カートリッジで精製し,逆相のHPLC条件で分析した.種々の食品について添加回収試験を行ったところ,回収率は83.0〜105.1%,相対標準差はおおむね5%以下であった.%A rapid dialysis method for the analysis of stevioside (SS) and rebaudioside A (RS) in foods was developed. Minced samples (10 g) were packed into 30 cm net length dialysis tubing with 30% methanol to increase the dialysis efficiency. The dialysis tubing was put in a 100 mL centrifuge tube, and the total fluid volume was made up to 100 mL with 30% methanol. Dialysis was done with shaking while heating at 50℃. The dialysis times were reduced from 48-72 hr in the conventional method to 2 hr under these conditions. The dialysate was loaded on a C18 solid- phase extraction cartridge, and the cartridge was washed with 40% methanol. SS and RS were eluted from the cartridge with 80% methanol, and separated by reversed-phase HPLC. Recovery yields (%) of SS and RS, spiked at 0.02 g/kg in various foods, were 83.0-105.1% and the relative standard deviations were mostly less than 5%.