Solid State NMR of Food and Biopolymers
Pp. 244-265 (22)
Cesar Augusto Tischer and Suzana Mali
Nuclear magnetic resonance (NMR) is widely applied in chemistry and
biochemistry, as well as in materials science. The capacity to elucidate new compounds
or recognize structures by a fingerprint are common uses of liquid state NMR. Solid
state NMR provides another added advantage to the analytical flux, as it can be
performed without multistep sample preparation and in a non-destructive way; these
aspects greatly speed up sample analysis. Research on mechanics and electronics in the
recent years has led to the development of hardware for solid state NMR and a more
versatile technique, cross polarization - magical angle spectroscopy (13C CP MAS).
These techniques are robust, operationally less expensive and reliable even when
performed by non-highly trained experts. These developments have allowed this
technique to be used for the analysis of food. Here, we present some technical
considerations for the implementation of solid state NMR as a reproducible technique,
considering typical NMR parameters such as the length of pulses and spectral
calibrations. The potential target compounds in food analysis are discussed regarding
the type of results that can be obtained; changes to the protein and lipid content and
quality lead to different spectra as well as physical-chemical characteristics with an
impact on the organoleptic and taste experience for consumers. The structure, crystal
arrangement and uses of the starch flour were reviewed to explain the role of materials
science tools and structural knowledge. Many techniques are used to perform state-o-
-the-art starch analysis and to assess its role in flour products; solid state NMR
spectroscopy has considerable potential as a quick, reliable and cost-beneficial way to
routinely validate processes and products. Finally, we suggest parameters for future
standardized experiments and the possible comparison with other analytical methods.
Analytical methods, Biopolymers, Food chemistry, Hydrocolloids,
Non-destructive method, Nuclear magnetic resonance parameters, Rapid method,
Solid state NMR, Starch, Ultrastructural characterization.
Department of Biochemistry and Biotechnology, State University of Londrina, Rodovia Celso Garcia Cid, PR445 Km 380, Campus Universitário, Cx. Postal 10.011, CEP 86057-970, Londrina, PR, Brazil.