【摘要】 采用空气 -乙炔火焰原子吸收光谱法分别测定了啤酒酵母发酵液中的Na+、K+、Mg2 +、Ca2 +离子动态变化中的含量 ,用La3 +盐消除P对Ca2 +的干扰 ,以Sr2 +盐作为Na +、K +的消电离剂。本实验室采用配制培养基 ,通过对不同种类及不同发酵阶段培养的发酵液样品进行测定 ,以研究在啤酒酵母生长代谢过程中Na +、K +、Mg2 +、Ca2 +离子代谢动态变化。方法的Na +、K +、Mg2 +、Ca2 +相对标准偏差 (RSD)分别为0.31 % ,0.73 % ,1.78 % ,0.28 % ;样品加标回收率为98 %～107 % ;检出限 :Na +为0.159mg/L ,K +为0.789mg/L ,Mg2 +为0.039mg/L ,Ca2 +为0.029mg/L。该方法简便快速 ,具有很好的精密度。更多还原

【Abstract】 A method was developed for the determination of dynamic concentration variations of Na + 、K + 、Mg 2+ 、Ca 2+ during the period of beer fermentation by air-acetylene flame atomic absorption specˉtrometry(FAAS).La 3+ was used to overcome the interference of P on Ca 2+ and Sr 2+ was used as deionizaˉtion agent for Na + and K + .A variety of fermentative samples at different stages were studied with the deˉveloped method.The result showed that the RSDs(n=11)were0.31%for Na + ,0.73%for K + ,1.78%for Mg 2+ and0.28%for Ca 2+ .The recoveries were98%～107%.The detection limits of the method were0.159mg/L for Na + 、0.789mg/L for K + 、0.039mg/L for Mg 2+ and0.029mg/L for Ca 2+ .The method is simple,rapid and accurate.更多还原