Nieuwoudt Hélène H, Pretorius Isak S, Bauer Florian F, Nel Daniel G, Prior Bernard A
Department of Microbiology, Stellenbosch University, Private Bag XI, 7602 Matieland, South Africa.
J Microbiol Methods. 2006 Nov;67(2):248-56. doi: 10.1016/j.mimet.2006.03.019. Epub 2006 May 11.
A rapid screening method for the evaluation of the major fermentation products of Saccharomyces wine yeasts was developed using Fourier transform infrared spectroscopy and principal component factor analysis. Calibration equations for the quantification of volatile acidity, glycerol, ethanol, reducing sugar and glucose concentrations in fermented Chenin blanc and synthetic musts were derived from the Fourier transform infrared spectra of small-scale fermentations. The accuracy of quantification of volatile acidity in both Chenin blanc and synthetic must was excellent, and the standard error of prediction was 0.07 g l(-1) and 0.08 g l(-1), respectively. The respective standard error of prediction in Chenin blanc and synthetic musts for ethanol was 0.32% v/v and 0.31% v/v, for glycerol was 0.38 g l(-1) and 0.32 g l(-1), for reducing sugar in Chenin blanc must was 0.56 g l(-1) and for glucose in synthetic must was 0.39 g l(-1). These values were in agreement with the accuracy obtained by the respective reference methods used for the quantification of the components. The screening method was applied to quantify the fermentation products of glycerol-overproducing hybrid yeasts and commercial wine yeasts. Principal component factor analysis of the fermentation data facilitated an overall comparison of the fermentation profiles (in terms of the components tested) of the strains. The potential of Fourier transform infrared spectroscopy as a tool to rapidly screen the fermentative properties of wine yeasts and to speed up the evaluation processes in the initial stages of yeast strain development programs is shown.
利用傅里叶变换红外光谱和主成分因子分析，开发了一种快速筛选方法，用于评估酿酒酵母的主要发酵产物。从小规模发酵的傅里叶变换红外光谱中得出了用于定量发酵白诗南葡萄酒和合成葡萄汁中挥发酸、甘油、乙醇、还原糖和葡萄糖浓度的校准方程。白诗南葡萄酒和合成葡萄汁中挥发酸定量的准确性极佳，预测标准误差分别为0.07 g l(-1)和0.08 g l(-1)。白诗南葡萄酒和合成葡萄汁中乙醇的预测标准误差分别为0.32% v/v和0.31% v/v，甘油的预测标准误差分别为0.38 g l(-1)和0.32 g l(-1)，白诗南葡萄汁中还原糖的预测标准误差为0.56 g l(-1)，合成葡萄汁中葡萄糖的预测标准误差为0.39 g l(-1)。这些值与用于定量各成分的相应参考方法所获得的准确性一致。该筛选方法用于定量甘油高产杂交酵母和商业葡萄酒酵母的发酵产物。对发酵数据进行主成分因子分析有助于对各菌株的发酵谱（就所测试的成分而言）进行全面比较。结果表明，傅里叶变换红外光谱作为一种工具，可快速筛选葡萄酒酵母的发酵特性，并加快酵母菌株开发计划初始阶段的评估过程。
