scholarly journals Interaction of proteins and amino acids with iso-α-acids during wort preparation in the brewhouse

2021 ◽  
Author(s):  
Nele Gänz ◽  
Tobias Becher ◽  
Stephan Drusch ◽  
Jean Titze
Keyword(s):  
Amino Acids ◽  
Bovine Serum Albumin ◽  
Free Amino ◽  
Amino Nitrogen ◽  
Titration Calorimetry ◽  
Preparation Process ◽  
Covalent Bonds ◽  
Binding Behavior ◽  
Ionic Bonds ◽  
Beer Foam

AbstractThis paper investigates the binding behavior of iso-α-acids from hops on free wort amino acids and proteins concerning the wort production process in breweries. The studies were carried out with different amino acids, bovine serum albumin and wort. To identify the nature of reaction between iso-α-acids and these substances, analyses of free amino nitrogen, HPLC and isothermal titration calorimetry were performed. According to the results, the iso-α-acids do not form covalent bonds with free amino acids of wort. However, iso-α-acids, especially isohumulone and isoadhumulone, form ionic bonds with wort proteins. A distinction must be made between proteins that are present in the hot trub, and those that are still dissolved in the hot wort. Proteins that are already coagulated and precipitated no longer react with iso-α-acids. Future experiments will investigate whether the established ionic bonds between iso-α-acids and proteins from the wort preparation process are maintained during fermentation until the finished beer or beer foam. If this is the case, which is induced by the experiments, there is a measurable loss of iso-α-acids in the hot wort, but at the same time, a gain for the later beer foam retention, as the iso-α-acids will stabilize it.

MATHEMATICAL MODELS FOR THE SYNTHESIS OF PLANT-BASED COMPOSITIONS WITH IMPROVED AMINO ACID COMPOSITION

2021 ◽  
Author(s):  
Irina Gaivoronskaya ◽  
Valenitna Kolpakova
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Mathematical Models ◽  
Functional Properties ◽  
Amino Nitrogen ◽  
Essential Amino Acids ◽  
Major Allergen ◽  
Structural Features ◽  
Covalent Bonds ◽  
Pea Protein

The aim of the work was to optimize the process of obtaining multicomponent protein compositions with high biological value and higher functional properties than the original vegetable protein products. Was realized studies to obtain biocomposites on the base of pea protein-oat protein and pea protein-rice protein. Developed composites were enriched with all limited amino acids. For each of the essential amino acids, the amino acid score was 100% and higher. Protein products used in these compositions are not in major allergen list, which allows to use these compositions in allergen-free products and specialized nutrition. To determine biosynthesis parameters for compositions from pea protein and various protein concentrates with the use of transglutaminase enzyme, was studied effect of concentration and exposition time on the amount of amino nitrogen released during the reaction. Decreasing of amino nitrogen in the medium indicated the occurrence of a protein synthesis reaction with the formation of new covalent bonds. Were determined optimal parameters of reaction: the hydromodule, the exposure time, the concentration of EP of the preparation, were obtained mathematical models. Studies on the functional properties of composites, the physicochemical properties of the proteins that make up their composition, and structural features will make it possible to determine the uses in the manufacture of food products based on their ability to bind fat, water, form foam, gels, and etc.

The effect of starvation and low nitrogen intakes on the concentration of free amino acids in the blood plasma and on the nitrogen metabolism in sheep

1970 ◽  
Vol 21 (5) ◽  
pp. 723 ◽  
Author(s):  
J Leibholz
Keyword(s):  
Amino Acids ◽  
Free Amino Acids ◽  
Free Amino ◽  
Dry Matter ◽  
Control Diet ◽  
Amino Nitrogen ◽  
Essential Amino Acids ◽  
Isoleucine Leucine ◽  
Plasma Urea ◽  
Low Nitrogen

Crossbred wethers were given a control diet (8 g nitrogen, 730 g dry matter daily) or a low nitrogen diet (0.5 g nitrogen, 520 g dry matter daily) or starved, for a 12 or 20 day experimental period. The concentrations of free serine, glutamine, glycine, alanine, histidine, and arginine in the plasma of the starved sheep decreased significantly while the concentrations of lysine, 3-methylhistidine, and isoleucine increased significantly. The ratio of essential to non-essential amino acids increased from 0.35 to 0.56 in the starved sheep. In sheep on the low nitrogen diet, the ratio of essential to non-essential amino acids in the plasma decreased from 0.40 to 0.27, with significant increases in the concentrations of glutanlic acid, glutamine, glycine, isoleucine, leucine, and 3-methylhistidine. Starvation and the low nitrogen diet both resulted in a reduction of the plasma urea concentrations. Starvation and the low nitrogen diet resulted in a 20-50 % reduction in the flow of saliva and a 40-78% increase in the concentration of total nitrogen. This resulted in no significant change in the daily secretion of nitrogen in the saliva. The concentration of urea in the saliva was increased by 3-54%. The concentrations of individual free amino acids in saliva are reported. The nitrogen content of the rumen was reduced, and after 7 days of starvation or on the low nitrogen diet all rumen nitrogen could be attributed to ammonia and free �-amino nitrogen.

scholarly journals Free Amino Nitrogen in Brewing

Fermentation ◽  
2019 ◽  
Vol 5 (1) ◽  
pp. 22 ◽  
Author(s):  
Annie Hill ◽  
Graham Stewart
Keyword(s):  
Amino Acids ◽  
Free Amino ◽  
Amino Nitrogen ◽  
Aroma Compounds ◽  
Ethanolic Fermentation ◽  
Methods Of Analysis

The role of nitrogenous components in malt and wort during the production of beer has long been recognized. The concentration and range of wort amino acids impact on ethanolic fermentation by yeast and on the production of a range of flavour and aroma compounds in the final beer. This review summarizes research on Free Amino Nitrogen (FAN) within brewing, including various methods of analysis.

Action of proteolytic enzymes on wheat gluten

1968 ◽  
Vol 46 (9) ◽  
pp. 1019-1022 ◽  
Author(s):  
Hung-Ju Yang ◽  
A. G. McCalla
Keyword(s):  
Amino Acids ◽  
Free Amino ◽  
Proteolytic Enzymes ◽  
Wheat Gluten ◽  
Amino Nitrogen ◽  
Protein Nitrogen ◽  
Early Stages ◽  
Mean Size ◽  
Terminal Amino ◽  
The Mean

Papain and trypsin partially hydrolyzed wheat gluten dispersed in 10% sodium salicylate, and pepsin partially hydrolyzed gluten dispersed in aluminium lactate. Trypsin was considerably less effective than either papain or pepsin. Papain produced non-protein nitrogen most rapidly during early stages of hydrolysis but pepsin produced the largest total after 48 h. The rate of release of terminal amino nitrogen was similar for papain and pepsin, and release was not complete after 48 h. The mean size of polypeptides was larger in papain than in pepsin hydrolysates during early stages of hydrolysis but definitely smaller after 48 h. Only pepsin released appreciable amounts of free amino acid nitrogen. Leucine and phenylalanine made up over 50% of the free amino acids after 48 h but several other amino acids were found in significant quantities.

The costs of cell volume regulation: protein metabolism during hyperosmotic adjustment

1992 ◽  
Vol 72 (3) ◽  
pp. 569-578 ◽  
Author(s):  
A. J. S. Hawkins ◽  
T. J. Hilbish
Keyword(s):  
Amino Acids ◽  
Cell Volume ◽  
Protein Metabolism ◽  
Free Amino Acids ◽  
Volume Regulation ◽  
Free Amino ◽  
Cell Volume Regulation ◽  
Amino Nitrogen ◽  
Body Protein ◽  
Metabolic Pool

To resolve the sources of amino nitrogen which is accumulated as intracellular solute during hyperosmotic volume regulation, components of protein metabolism were monitored during compensation for a change from 15 to 30% salinity in the blue mussel, Mytilus edulis L. Net solute gain stemmed primarily from a marked reduction in total output from the metabolic pool of free amino acids, most of this ‘saving’ resulting from slower whole-body protein synthesis, and the remainder from lower nitrogenous excretion. Indeed, total inputs to the metabolic pool of free amino acids actually decreased over the period of net solute gain at 30%. Associated contributions from dietary assimilation, de novo synthesis and the direct uptake of dissolved amino acids were each negligible, indicating that breakdown products from endogenous body protein were the only significant source of amino nitrogen accumulated during hyperosmotic regulation. This accumulation represented more than 3% of soft-tissue protein nitrogen within the whole animal. We therefore impress that the excretion, during hyposaline adjustment, of all nitrogen previously accumulated as solute in response to equivalent hypersaline change, represents a major component cost of cell volume regulation, and which helps to explain stress and even mortality consequent upon what may be small but frequent fluctuations of salinity.

Biotechnological Aspects of obtaining Functional Ingredients by the Conversion of Saccharomyces cerevisiae 985-Т Biomass

2020 ◽  
Vol 36 (4) ◽  
pp. 34-41
Author(s):  
L.V. Rimareva ◽  
M.B. Overchenko ◽  
N.I. Ignatova ◽  
N.V. Shelekhova ◽  
N.S. Pogorzhelskaya ◽  
...  
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Amino Acids ◽  
Free Amino Acids ◽  
Free Amino ◽  
Fractional Composition ◽  
Amino Nitrogen ◽  
Degree Of Hydrolysis ◽  
Amine Nitrogen ◽  
Functional Ingredients ◽  
Hydrolysis Of

An algorithm for the biocatalytic conversion of polymers of subcellular structures of Saccharomyces cerevisiae 985-T has been developed. It was shown that the action of enzymes on cell wall mannoproteins and (3-glucans led to deformation of their structure and the transfer of more than 50% of polysaccharides to a soluble state with the formation of 13.4% reducing carbohydrates, 1.8% amine nitrogen and 7.7% free amino acids (biological-1). Biological-2 had an increased content of total carbohydrates (32.2%) and fiber (10.5%). It was found that the combined action of the complex of proteinases and peptidases contributed to an increase in the degree of hydrolysis of subcellular structures, which was accompanied by a growth of the content of amino nitrogen by 2.7 times, free amino acids by 3.1 times, and low-molecular peptides (up to 500 Da) by 3.5 times (biological-3). The obtained biologicals were characterized by a high content of phosphorus and potassium. It was shown that the use of enzyme systems that catalyze the hydrolysis of intracellular polymers in yeast biomass allows us to obtain products with different biochemical and structural-fractional composition, which determines their properties. Saccharomyces cerevisiae, enzymes, structural-fractional composition, functional ingredients The work was carried out at the expense of the subsidy for the implementation of the State Task.

A SIMPLE ULTRAMICROMETHOD FOR THE QUANTITATIVE ESTIMATION OF AMINO ACIDS BY PAPER PARTITION CHROMATOGRAPHY

1952 ◽  
Vol 30 (2) ◽  
pp. 109-113 ◽  
Author(s):  
Jacques L. Auclair ◽  
Robert Dubreuil
Keyword(s):  
Amino Acids ◽  
Free Amino Acids ◽  
Free Amino ◽  
Galleria Mellonella ◽  
Quantitative Estimation ◽  
Larval Instar ◽  
Amino Nitrogen ◽  
New Method ◽  
Partition Chromatography

A new ultramicromethod for the quantitative estimation of amino acids by paper partition chromatography is described. The material required and the procedure adopted are detailed. As an application of this new method, a quantitative estimation of the free amino acids present in the blood of the last larval instar of Galleria mellonella (L.) is presented. The results obtained, when converted into total amino nitrogen, compare favorably with total amino nitrogen results already published in the literature.

Sign in / Sign up

Export Citation Format

Share Document