ATR-FTIR spectroscopy for in-line anomer concentration measurements in solution: A case study of lactose. (April 2020)

• Record Type: Journal Article
• Authors: Schiele, Simon A.; Meinhardt, Rolf; Eder, Cornelia; Briesen, Heiko
• Is Part Of: Food control. Volume 110(2020)
• Publication Date: 2020-04
• Subjects: Lactose -- Mutarotation -- Crystallization -- Control -- ATR-FTIR -- Process analytical technology (PAT); ATR-FTIR attenuated total reflection Fourier-transform infrared -- FBRM focused beam reflection method -- PAT process analytical technology -- PCR principal component regression -- PLS partial least squares -- ROI region of interest; Food -- Quality -- Periodicals; Food -- Analysis -- Periodicals; Food handling -- Periodicals; Food industry and trade -- Quality control -- Periodicals; Aliments -- Industrie et commerce -- Qualité -- Contrôle -- Périodiques; Aliments -- Qualité -- Périodiques; Aliments -- Analyse -- Périodiques; Hygiène alimentaire -- Périodiques; Food -- Analysis; Food handling; Food -- Quality; Periodicals; Electronic journals; 664.07
• DOI: 10.1016/j.foodcont.2019.107024
• Languages: English
• ISSNs: 0956-7135

Abstract

Abstract: Crystalline lactose is used in a variety of food and pharmaceutical products, and its crystallization is an important process in the dairy industry. However, the dynamics of lactose crystallization are complicated and, therefore, hard to predict. One reason for this is the mutarotation of lactose molecules, and, currently, there is no in-line technique for the measurement of mutarotation. Herein, we report on attenuated total reflection Fourier-transform infrared spectroscopy, a powerful in-line tool that simultaneously measures both total lactose concentration and the concentration of one of its anomers, α -lactose. Applying this method in a lab-scale crystallization reactor, we use it to measure the mutarotation kinetics of lactose over a wide range of temperatures and pH values to demonstrate its applicability for the crystallization of lactose based on process analytical technology. Highlights: The ATR-FTIR spectrum of lactose solutions depends on the state of mutarotation. The state of mutarotation of lactose solutions can be measured in-line. With this information the supersaturation of α -lactose is accessible. The proposed method can be applied for PAT based crystallization of lactose.