Suchergebnisse

Department of Applied Chemistry, Government Engineering College, Jabalpur (M. P.) Manuscript received 4 March 1978, revised 24 July 1978, accepted 22 August 1978 Kinetics of the reaction between amberlite IR-120 resin and propionamide solution have been studied at different temperatures as well as at different concentrations of the reactants. The reaction has been found to be pseudo first order. The rate constant increases with an increase in resin concentration and attains an optimum value. Arrhenius parameters have been computed. The mechanism has been proposed on the basis of experimental results.

Department of Applied Chemistry, Government Engineering College, Jabalpur, M. P. Manuscript received 17 March 1977, revised 22 July 1977, accepted 29 July 1977 Kinetics of the reaction between resin and formamide have been studied at different temperatures. I he rate of the reaction has been followed by conductance measurements. The reaction has been found to be first order with respect to formamide and independent to resin concentration. The rate constant increase with an increase in resin concentration and attains optimum value. Arrhenius parameters and kinetic order support a unimole­cular nucleophilic attack of water molecule on the conjugate acid species of formamide

The stability of the sucrose molecule throughout processing is of the utmost importance, because in principle any sugar loss will increase the production costs per tonne of the obtained white sugar. Colour in processing is an important technological parameter too, since only an adequate colour control in processing allows the cost-effective production of white sugar crystals of the required quality. For process control of both sugar hydrolysis and colour formation it is necessary to understand the effect of pH value, temperature and retention time on these phenomena. This paper will describe the possible causes of sugar hydrolysis and colour, as well as how to control pH values and temperature in processing in order to limit the technological impact of both reactions in which invert sugar plays a central role.

Large amounts of different peptides are naturally generated in dry-cured meats as a consequence of the intense proteolysis mechanisms which take place during their processing. In fact, meat proteins are extensively hydrolysed by muscle endo-peptidases (mainly calpains and cathepsins) followed by exo-peptidases (mainly, tri- and di-peptidyl peptidases, dipeptidases, aminopeptidases and carboxypeptidases). The result is a large amount of released free amino acids and a pool of numerous peptides with different sequences and lengths, some of them with interesting sequences for bioactivity. This manuscript is presenting the proteomic identification of small peptides resulting from the hydrolysis of four target proteins (glyceraldehyde-3-phosphate dehydrogenase, beta-enolase, myozenin-1 and troponin T) and discusses the enzymatic routes for their generation during the dry-curing process. The results indicate that the hydrolysis of peptides follows similar exo-peptidase mechanisms. In the case of dry-fermented sausages, most of the observed hydrolysis is the result of the combined action of muscle and microbial exo-peptidases except for the hydrolysis of di- and tri-peptides, mostly due to microbial di- and tri-peptidases, and the release of amino acids at the C-terminal that appears to be mostly due to muscle carboxypeptidases. ; The research leading to these results received funding from the European Union Seventh Framework Programme (FP7/2007–2013) under Grant Agreement 312090 (BACCHUS). This publication reflects only the author views and the community is not liable for any use made of the information contained therein. JAEDOC-CSIC postdoctoral contract cofunded by European Social Fund to L.M. and FPI Scholarship to M. G. are also acknowledged. ; Peer Reviewed

[EN] Large amounts of different peptides are naturally generated in dry-cured meats as a consequence of the intense proteolysis mechanisms which take place during their processing. In fact, meat proteins are extensively hydrolysed by muscle endo-peptidases (mainly calpains and cathepsins) followed by exo-peptidases (mainly, tri- and di-peptidyl peptidases, dipeptidases, aminopeptidases and carboxypeptidases). The result is a large amount of released free amino acids and a pool of numerous peptides with different sequences and lengths, some of them with interesting sequences for bioactivity. This manuscript is presenting the proteomic identification of small peptides resulting from the hydrolysis of four target proteins (glyceraldehyde-3-phosphate dehydrogenase, beta-enolase, myozenin-1 and troponin T) and discusses the enzymatic routes for their generation during the dry-curing process. The results indicate that the hydrolysis of peptides follows similar exo-peptidase mechanisms. In the case of dry-fermented sausages, most of the observed hydrolysis is the result of the combined action of muscle and microbial exo-peptidases except for the hydrolysis of di- and tri-peptides, mostly due to microbial di- and tri-peptidases, and the release of amino acids at the C-terminal that appears to be mostly due to muscle carboxypeptidases. ; The research leading to these results received funding from the European Union Seventh Framework Programme (FP7/2007-2013) under Grant Agreement 312090 (BACCHUS). This publication reflects only the author views and the community is not liable for any use made of the information contained therein. JAEDOC-CSIC postdoctoral contract cofunded by European Social Fund to L.M. and FPI Scholarship to M. G. are also acknowledged. Mass spectrometry analysis was performed in the in the SCSIE_University of Valencia Proteomics Unit, a member of ISCIII ProteoRed Proteomics Platform. ; Mora Soler, L.; Gallego Ibáñez, M.; Escudero, E.; Reig Riera, MM.; Aristoy, MC.; Toldrá Vilardell, F. (2015). Small ...

Using advanced enzymatic starch conversion technologies followed by modern separation and purification processes and blending practices provide today a manifold of nutritive syrups and powders offering a wide range of carbohydrate functionalities. High fructose syrups and glucose syrups comprising high dextrose and high maltose syrups, available also in their dried or pure crystalline forms, cover a wide range of food, pharmaceutical and technical applications. Beyond controlled sweetness starch saccharification products provide a diversity of physical properties such as viscosity, reducing sugar content, osmotic pressure, crystallisation retardation, gloss, humectancy, consistency and many others.

AbstractThe effect of temperature, time and amount of enzyme on hydrolysis of wheat straw lignocellulose remaining after furfural production was studied. The residual substrate was subjected to enzymatic hydrolysis at different temperatures — 45 °C, 50 °C and 55 °C. Hydrolysis time was 72 hours, and samples were taken every 24 hours. The maximum glucose yield (76.5% of the theoretically possible) was reached when hydrolysis temperature 50 °C was used. The production rate of glucose increased with a hydrolysis period of time. The yield of glucose significantly depended on the ratio of enzyme to substrate.