The Chemical Fingerprint of Beer from a Single Experiment with Minimum Sample Preparation – A Rapid Quantitive Analysis by 1H NMR Spectroscopy

NMR Spectroscopy is the premier tool utilized by chemists to obtain detailed chemical information on molecular structure and is used extensively in molecular structure verification, chemical purity analysis, and complex mixture analysis. We have developed a quantitative NMR analysis that yields a chemical fingerprint that brewers can utilize to follow detailed variations in the chemistry observed in the various stages of the brewing process (malting, mashing, boiling, fermentation, ageing, and blending). The analysis observes all molecules in the beer at the same time and each molecular component (acids, alcohols, amino acids, malt-oligosaccharides) yields a unique spectral fingerprint pattern that is related to the structure of the molecule. Though the spectrum consists of a large number of overlapped individual fingerprints it is possible to identify and quantify individual components because many components have signals that appear at unique and specific points in the spectrum. The quantitative analysis is performed by comparing the area under the individual molecule signals to that of an internal standard (Maleic Acid 99%). Molecular components are quantified on a weight/volume basis in mg/L (parts-per million). Ethanol is also quantified on a %volume/volume basis. The technique is not only applicable to the brewing process but is also being…

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Quantitative 1H NMR Analysis of “Off-the-Shelf” Commercial Kombucha Beverages for Ethanol, Organic Acids and Residual Sugars Analysis

Over the past few years our analytical NMR service has been developing a detailed chemical fingerprint analysis of alcoholic beverages by quantitative 1H NMR (qHNMR). Beyond the typical analyses of beer, wine, port, hard cider, sake and spirits, we have been looking at other fermented beverages such as kombucha, kefir, kvass, mead, ginger beer and perry. As well as the final fermented beverages we have been actively investigating the various starting materials such as malt wort, apple juice, honey, grape juice, fruit juices, and tea. The NMR analysis can provide a rapid quantitative analysis without any sample preparation based on the molar ratio of integration value of unique molecular fingerprint peaks with the integrated signal of an internal standard. In our case we typically use maleic acid as an internal standard as it’s singlet signal peak appears in a non-overlapping are of the spectrum to the chemistry we are interested in following. The information that can be derived from the NMR experiment covers a wide dynamic range of component molecule concentrations from 10-100,000 ppm. The analysis observes all fully dissolved chemical constituents and the spectral response is linear with regard to all chemical types. As a primary analytical method the…

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Residual Catalytic Cracker – Heavy Petroleum Feedstream Properties from 1H NMR at 43 MHz

Back in October we presented a talk at Gulf Coast Conference that concerned the prediction of the chemical and physical properties of heavy petroleum feeds being converted to higher value product in a residual catalytic cracker (RCC). Over the years we have analyzed these materials by 300 and 60 MHz NMR and obtained good PLS-regression models that can adequately predict properties for real-time process control and optimization in a petroleum refinery. With the advent of a large number of new benchtop NMR systems we have been convincing ourselves that these types of analyses can be performed by systems such as the Magritek Spinsolve 43 MHz. We ran a series of samples that had been sitting around our lab for 15 years by dissolving them at about 50 volume% in a 50/50 CDCl3/CS2 solvent system. For each sample we had laboratory test data for a number of chemical and physical properties of interest to process engineers. We regressed the lab data variability against the variability in the Magritek 43MHz 1H NMR spectra and obtained cross-validated PLS models. The presentation material is given here at this link - Gulf Conference Presentation - 43 MHz RCC Feedstream Regression Models

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Beer and Cider Analysis – Example of Spectral Repeatability of Benchtop 60 MHz NMR System

Here is an example of spectral reproducibility. We are doing a lot of beer NMR at the moment on our 300 MHz NMR and for "giggles" we are running many samples through the various bench-top systems in our lab. We have been quantifying small organic acids (lactic, acetic, succinic , malic, citric, etc.) as they can give some idea of yeast activities and health during fermentation. We are also quantifying  and studying the 1,4/1,6 linkage distribution of residual dextrins. The series of superimposed spectra below consists of 28 spectra of a freeze dried beer sample (a unique Belgian Dubbel. Each spectrum was 128 pulses and took approximately 30 minutes per spectrum. So the superimposed data represents a 14 hour continuous stability test.The data was automatically processed with 16K zero-fill and autophase.It looks pretty damn good.   We've been looking at a lot of sour beers - here is a home-brewed Flemish Red aged in an oak barrel - note the high lactic and acetic content. We've also been analyzing a lot of hard ciders - commercial and home-brewed varitieties of various styles - very different from one sample to another in the small molecule and sugar chemistry.     1H…

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From Atoms to Flavour: The Chemistry of Beer

Adam DiCaprio (ex PNA) gave an excellent Science Cafe Talk under the auspices of the ACS North Carolina Section at the Busy Bee Cafe in downtown Raleigh on December 2, 2014. CHanging gears from his previous talks he centered the discussion on malt and hop chemistry as well as an start-to-finish NMR analysis of production runs of a bottled commercial tavern ale. If you are interested in having Adam give a detailed chemistry seminar on beer at your section meetings please contact him directly at adam@process-nmr.com. A PDF version of his talk is available here .... ACS Science Cafe Talk - Dicaprio - Busy Bee Cafe - Raleigh NC - 12-2-14

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Whole Leaf Marker and Maltodextrin in Aloe Vera Raw Materials – Dry Weight Quantity – Extended 1H NMR Analysis Method

Process NMR Associates has developed an extension of its 1H NMR analysis of Aloe Vera raw materials and products analysis. Powder aloe vera raw materials (100x/200x) can be analyzed directly and juice samples (1x, 5x, 10x, commercial products) must be freeze dried for this analysis. The whole leaf markers utilized in this test to indicate the presence of whole leaf material are iso-citrate and iso-citrate lactone which are formed in the green leaf part of the aloe plant as part of the citric acid cycle. It is possible to assign and quantify the following components of an aloe vera juice or powder: * aloe vera components: acemannan, glucose, malic acid * whole leaf markers: isocitrate, iso-citrate lactone, citric acid * degradation products: lactic acid, acetic acid, fumaric acid, pyruvic acid, formic acid, succinic acid, and ethanol * adulterants: maltodextrin * preservatives: sorbate, benzoate * additives: sucrose, fructose, glycine, flavorants (contain ethanol and propylene glycol) For the components above it is possible to obtain a wt% of that component in a juice sample - the freeze drying process is then used to determine the wt% solids in the juice and the dry weight concentrations of the organic components in the solids.…

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Talks to be Presented at IFPAC 2012 – Baltimore, MD January 22-25

Talk 1 by John Edwards Mutivariate Analysis of 1H and 13C NMR Data of Residual Catalytic Cracker Feed-Streams: NMR Pre-Processing Strategies that Allow the Development of Predictive Models of Physical and Chemical Properties that are Independent of NMR Instrument Magnetic Field Strength John C. Edwards*# and Jincheol Kim† *Process NMR Associates, LLC, 87A Sand Pit Rd, Danbury, CT 06810 USA † SK Innovation Co., Ltd, SK Innovation Technology Center, 140-1, Wonchon-dong, Yuseong-gu, Daejeon 305-712, Korea # Speaker Historically refinery control engineers are familiar with GC derived chemical properties such as aromatics, benzene, PONA, olefins in wt% or vol%, as well as physical properties such as distillation, viscosity, conradson carbon, sulfur, density, etc. We have developed generally applicable multivariate regression methods that allow many of these familiar chemical and physical properties to be derived from quantitative 1H or 13C NMR data. We have also developed magnetic field independent data manipulation methods that allow 1H or 13C NMR derived parameters to be utilized as the X matrix “spectral” data rather than the spectra themselves. This allows field independent models to be developed as these parameters are calculated from the spectrum and are the same regardless of the magnetic field strength at which…

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IFPAC Conference: Process NMR Associates and University of California, Davis to Present Process NMR and MRI Short Course Prior to Meeting

Short Course on Process NMR and MRI to be presented at the IFPAC Meeting (http://www.ifpac.com/) When: Monday, January17, 1:00pm to 5:00pm, and continues on Tuesday January 18, 8:00AM to 12 noon Location: Baltimore Marriott Waterfront Instructors: Michael J. McCarthy, Professor of Engineering, University of California, Davis, CA Paul J. Giammatteo, Ph.D., Process NMR Associates LLC, Danbury, CT The course is specifically designed and organized for industry professionals who want to add to their knowledge-base on magnetic resonance and process analytical technology. Topics include compositional analysis, rheological characterization, measurement of the state of mixing, visualizing transport and product stability as well as recent advances in process magnetic resonance sensors. This course will bring you up-to-date on the latest information concerning the applications and state-of-the art instrumentation for process magnetic resonance. Outline: * Introduction to Process NMR Magnetic resonance theory - Time-domain, High resolution, Diffusion, Imaging * Hardware - Spectrometers, magnets, probes * Coupling the sensor to the process * Applications will include: - Composition measurement - Property measurement - Rheology measurement - Product structure For Details contact Paul Giammatteo Tel: (203) 744-5905 or Michael McCarthy Tel: (530) 752 8921

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