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Brewing Chemistry Analysis –    Quality Assurance –

 Profile of Metabolic Enzyme  CO2 Determination



 Material production using microorganisms such as   Yeast strain S288C and single gene deletion mutants of strain   Quality assurance is only one of the attributes for brand name   bottles, carbon dioxide ensures that the necessary pressure is
 Saccharomyces Cerevisiae has been applied to fermented food   BY4742 were cultured in media containing non-labeled or C-13   products such as beer. And quality is dependent on the quality   maintained. This is an important factor for guaranteeing shelf
 such as beer. These microbial cell factories have been   labeled glucose for metabolic enzyme analysis. Strain S288C   of the starting materials, strict production processes as well as   life and fresh-tasting beer. A constant concentration of carbon
 metabolically engineered by regulating the expression levels of   grown in heavy C-13 labeled glucose acted as an internal   specialists whose keen eyes oversee the entire production.   dioxide also ensures a steady taste and consistent quality of the
 enzymes. To understand these metabolic pathways, it is   standard for comparison to the light C-12 mutated growth   Finally, millions of consumers are testing their favorite brand of   beer. Beer contains 4 – 6 g/L CO2.
 important to monitor the abundance of enzymes. Metabolic   strains*. Information regarding glycerol biosynthesis, ethanol   beer every day.   Carbon dioxide in the world of Total Organic Carbon (TOC)
 enzymes can be subjected to trypsin digestion, and   pathway, tricarboxylic acid (TCA) cycle, polysaccharides, and   An important player in the production process and a condition   analyzers is referred to as Inorganic Carbon (IC). The IC method
 representative tryptic peptides selected for analysis. LC-MS/MS is   amino acids was determined by LC-MS/MS analysis. In one   for quality is invisible: carbon dioxide (CO2), formed during the   is a suitable alternative to the classical Corning reference
 a highly sensitive and specific analytical technique used for   example, the LCMS-8050 measured 303 peptides of 137 proteins   fermenting process. After filling the beer into barrels and   method for measuring CO2*.
 quantitation of specific peptides in biological samples. Unlike   by monitoring 2856 MRM transitions#. The library* for
 ELISA, LC/MS-based MRM (Multiple Reaction Monitoring)   metabolic enzymes in yeast contains 3,584 MRM transitions,
 approaches do not require an antibody for each   including stable isotopes. It covers all 498 trypsin digested
 protein/peptide.   peptides of 228 types of enzymes derived from budding yeast.




 12
 Light: Culture with  C  Glucose
 6
 Tryptic
 Yeast A  peptide
 Cultivation
 12
 ( C Glucose)  cell collection  extraction  digestion
 Heavy: Culture with  C  Glucose  Light  Inorganic Carbon (IC) measured as CO 2 in beer by a TOC analyzer*
 13
 6                                                                     Shimadzu TOC-L Total Organic Carbon analyzer for the analysis of CO 2
 Heavy
 Tryptic  MRM analysis
 Yeast B  peptide
 Cultivation
 13
 ( C Glucose)  cell collection  extraction  digestion  6
                                                                                      Corning  TOC
                                        5.5
                                         5
                                        Co2 [g/L]  4.5
 Pdc1  Pdc6  Adh1  Adh3
                                         4
                                        3.5
                                         3
 Adh6  Ald4  Ald5  Ald6                      beer1  alcohol-free  beer2  alcohol-free  beer3  beer4  unfiltrated
                                                     beer1          beer2                   beer4
                                         CO2 concentration measured by TOC and Corning reference method for various beers*


 Metabolic profile of Ethanol pathway enzyme levels in wild type (black)   Shimadzu LCMS-8050 for measuring metabolic enzymes in yeast
 and three deletion strains (greys) of S. cerevisiae. #












 * Shimadzu Brochure C146-E275: “LC/MS/MS MRM Library for Metabolic Enzymes in Yeast”
 #   Shimadzu Corporation Application Data Sheet: “Quantitative proteomics of metabolic enzymes in S. cerevisiae with UFMS technologies”

                                                               Shimadzu’s Total Support for Beer Analysis
 24                                                                                                  Analytical and Testing Instruments for Beer  25
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