Monitoring acid-catalyzed hydrolysis of sucrose through low-resolution NMR relaxometry
4th International Conference and Exhibition on Food Processing & Technology
August 10-12, 2015 London, UK

Mecit Halil Oztop, Simge Tutku Yildirim and Alper Soyler

Scientific Tracks Abstracts: J Food Process Technol

Abstract:

Reaction monitoring is usually achieved by high-resolution spectrometric and chromatographic techniques such as GC-MS,
NMR and Raman Spectroscopy. These instruments are designed such that continuous monitoring of products and reactant in
a reaction is not possible. Low-Resolution NMR systems provide easy designs to implement a continuous reaction system to the
instrument. NMR is a non-invasive and non-destructive method that takes signal from whole sample and enables to evaluate signals
from different compartments with varying proton environments. T2 NMR Relaxometry is based on measuring spin-spin relaxation
signal (CPMG) and then decomposing the signal through a mathematical transformation known as Non Negative Least Square. In
this study, NMR Relaxometry monitored acid hydrolysis of sucrose through T2-CPMG experiments. The acid hydrolysis experiments
were designed to develop an accurate and quick repeatable method for the concentration determination of the hydrolysis product.
Acid hydrolysis of sucrose was studied at different concentrations of sucrose (10%, 15% and 20% w/w). pH 2.5, HCl solution was
used at 30oC as the hydrolysis media. T2 relaxation times of the solutions were measured at pre-determined time intervals. Reducing
sugar concentration was determined by the DNS (3, 5-dinitrosalicylic acid). 2 T2 peaks were detected based on NMR Relaxometry
results. The T2 values of peaks showed significanthigh correlations (p<0.05) with the reducing sugar content. However, for different
concentrations of sucrose different peaks of T2 gave better results.

Biography :

Mecit Halil Oztop is a faculty member in the Department of Food Engineering at Middle East Technical University (METU), Ankara Turkey. His current research includes
application of MRI/NMR relaxometry in food science and designing active packaging systems. He received his PhD degree from University of California, Davis Biological
Systems Engineering on 2012 and started to work as faculty at METU right after.