Effects of the Deacetylation Degree of Chitosan on 2-Amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) Formation in Chemical Models and Beef Patties

Alternative interpretation of substituent effects (AISE) starts from the presumption that a substituent only possesses a single property described by a single substituent constant. This property is transmitted to the reaction centre by three different ways depending on the interaction type in the triad reaction centre - basic skeleton - substituent. For interpretation it is substantial whether or not the substituent has p electrons at the atom adjacent to the basic skeleton. If it has none, the substituent belongs to class I and operates only by its basic effect described by the mentioned single substituent constant. Substituents of class II possess a free electron pair at the atom adjacent to the basic skeleton, and those of class III have a multiple bond between the first and the second atoms which is polarized in the direction from the basic skeleton. Substituent effects in class I are described by a substituent constant identical with σI constant. Substituents in classes II and III show additional effects proportional to the same constant. Hence, a separate treatment of substituent effects in the individual classes provides three straight lines intersecting in a common point. Mathematically, the description of substituent effects in this approach is expressed by a family of lines with a single explaining variable. The point of intersection, which is referred to as the iso-effect point, is not identical with the classic standard substituent - hydrogen - but is near to CN substituent. The approach given has the advantage of adopting a single substituent constant whose scale can be adjusted relatively precisely. Its drawback (like in the case of the correlation equations derived from the principle of separation of substituent effects) lies in a more extensive set of substituents needed for a correlation. The AISE principle has been applied to 318 series of experimental data describing effects of 32 substituents in a large variety of chemical models (aliphatic, alicyclic, aromatic, heteroaromatic, with or without direct conjugation between reaction centre and substituent) in both chemical reactions and equilibria. A comparison with two other correlation relations with two and three substituent constants for interpretation of substituent effects based on the principle of separation of the individual substituent effects showed that the closeness of AISE based correlations is comparable with that of the correlation equations currently used. It was somewhat less successful in the models with direct conjugation between reaction centre and substituent but the AISE principle can be used even in these cases.

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Utilization of wheat germ oil and wheat bran fiber as fat replacer for the development of low‐fat beef patties

Food Science & Nutrition ◽

10.1002/fsn3.1988 ◽

2021 ◽

Author(s):

Anam Khalid ◽

Muhammad Sohaib ◽

Muhammad Tahir Nadeem ◽

Farhan Saeed ◽

Ali Imran ◽

...

Keyword(s):

Wheat Bran ◽

Wheat Germ ◽

Wheat Germ Oil ◽

Low Fat ◽

Fat Replacer ◽

Beef Patties

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Reduction of the Heterocyclic Amines in Grilled Beef Patties through the Combination of Thermal Food Processing Techniques without Destroying the Grilling Quality Characteristics

Foods ◽

10.3390/foods10071490 ◽

2021 ◽

Vol 10 (7) ◽

pp. 1490

Author(s):

Wei Wang ◽

Lu Dong ◽

Yan Zhang ◽

Huaning Yu ◽

Shuo Wang

Keyword(s):

Microwave Heating ◽

Food Processing ◽

Thermal Processing ◽

Superheated Steam ◽

Quality Characteristics ◽

Heterocyclic Amines ◽

Thermal Processes ◽

Beef Patties ◽

Thermal Food Processing ◽

Processing Techniques

In order to reduce the formation of heterocyclic amines in grilled beef patties without destroying their unique quality characteristics, the effects of different thermal processes, including charcoal grilling, infrared grilling, superheated steam roasting and microwave heating, on the production of heterocyclic amines in beef patties and grilling quality characteristics were systematically analyzed. The results showed that infrared grilling can significantly (p < 0.05) reduce the content of heterocyclic amines in grilled patties, and the combination of microwave heating or superheated steam roasting with infrared grilling could further reduce the content of heterocyclic amines, with a maximum reduction ratio of 44.48%. While subtle differences may exist in infrared grilled patties with/without superheated steam roasting or microwave heating, a slight change will not affect the overall quality characteristics of grilled patties. The combined thermal processing will not visually affect the color of the grilled patties. Correlation analysis and regression analysis showed that the reduction in heterocyclic amines caused by microwave heating and superheated steam roasting are related to the moisture content and lipid oxidation of grilled patties, respectively. Using combined thermal processes to reduce the formation of heterocyclic amines is advisable.

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Shellfish Chitosan Potential in Wine Clarification

Applied Sciences ◽

10.3390/app11104417 ◽

2021 ◽

Vol 11 (10) ◽

pp. 4417

Author(s):

Veronica Vendramin ◽

Gaia Spinato ◽

Simone Vincenzi

Keyword(s):

Molecular Structure ◽

Chemical Properties ◽

Allergic Reactions ◽

Chitin Content ◽

Deacetylation Degree ◽

Physical Chemical ◽

Similar Chemical ◽

Fungal Chitosan ◽

Significant Difference ◽

Fish Industry

Chitosan is a chitin-derived fiber, extracted from the shellfish shells, a by-product of the fish industry, or from fungi grown in bioreactors. In oenology, it is used for the control of Brettanomyces spp., for the prevention of ferric, copper, and protein casse and for clarification. The International Organisation of Vine and Wine established the exclusive utilization of fungal chitosan to avoid the eventuality of allergic reactions. This work focuses on the differences between two chitosan categories, fungal and animal chitosan, characterizing several samples in terms of chitin content and degree of deacetylation. In addition, different acids were used to dissolve chitosans, and their effect on viscosity and on the efficacy in wine clarification were observed. The results demonstrated that even if fungal and animal chitosans shared similar chemical properties (deacetylation degree and chitin content), they showed different viscosity depending on their molecular weight but also on the acid used to dissolve them. A significant difference was discovered on their fining properties, as animal chitosans showed a faster and greater sedimentation compared to the fungal ones, independently from the acid used for their dissolution. This suggests that physical–chemical differences in the molecular structure occur between the two chitosan categories and that this significantly affects their technologic (oenological) properties.

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Effect of roasting temperature on lipid and protein oxidation and amino acid residue side chain modification of beef patties

RSC Advances ◽

10.1039/d1ra03151a ◽

2021 ◽

Vol 11 (35) ◽

pp. 21629-21641

Author(s):

Chao Xia ◽

Pingping Wen ◽

Yaming Yuan ◽

Xiaofan Yu ◽

Yijing Chen ◽

...

Keyword(s):

Amino Acid ◽

Amino Acid Residue ◽

Protein Oxidation ◽

Relative Number ◽

Side Chain ◽

Amino Acid Residues ◽

Beef Patties ◽

Lipid And Protein Oxidation ◽

Roasting Temperature

The relative number of peptides modified by the amino acid residues of actin from raw beef patties and those cooked at different roasting temperatures.

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Chitosan-Based Adhesive: Optimization of Tensile Shear Strength in Dry and Wet Conditions

Polysaccharides ◽

10.3390/polysaccharides2010008 ◽

2021 ◽

Vol 2 (1) ◽

pp. 110-120

Author(s):

Maisa Abdelmoula ◽

Hajer Ben Hlima ◽

Frédéric Michalet ◽

Gérard Bourduche ◽

Jean-Yves Chavant ◽

...

Keyword(s):

Molecular Weight ◽

Shear Strength ◽

Bond Strength ◽

Water Resistance ◽

Tensile Shear Strength ◽

Tensile Shear ◽

Spread Rate ◽

Assembly Time ◽

Deacetylation Degree ◽

Dry And Wet Conditions

Commercial adhesives present a high bond strength and water resistance, but they are considered non-healthier products. Chitosan can be considered as an interesting biosourced and biodegradable alternative, despite its low water resistance. Here, its wood bonding implementation and its tensile shear strength in dry and wet conditions were investigated depending on its structural characteristics. Firstly, the spread rate, open assembly time, drying pressure, drying temperature, and drying time have been determined for two chitosans of European pine double lap specimens. An adhesive solution spread rate of 1000 g·m−2, an open assembly time of 10 min, and a pressure temperature of 55 °C for 105 min led to a bond strength of 2.82 MPa. Secondly, a comparison between a high molecular weight/low deacetylation degree chitosan and a lower molecular weight/higher deacetylation degree chitosan was conducted. Tests were conducted with beech simple lap specimens in accordance with the implementation conditions and the conditioning treatments in wet and dry environments required for thermoplastic wood adhesive standards used in non-structural applications (EN 204 and EN 205). The results clearly revealed the dependence of adhesive properties and water resistance on the structural features of chitosans (molecular weight and deacetylation degree), explaining the heterogeneity of results published notably in this field.

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Carbon-chain molecules in molecular outflows and Lupus I region – new producing region and new forming mechanism

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz1498 ◽

2019 ◽

Vol 488 (1) ◽

pp. 495-511

Author(s):

Yuefang Wu ◽

Xunchuan Liu ◽

Xi Chen ◽

Lianghao Lin ◽

Jinghua Yuan ◽

...

Keyword(s):

Radio Telescope ◽

Molecular Cloud ◽

Carbon Chain ◽

Species Range ◽

Chain Molecules ◽

Forming Mechanism ◽

Molecular Outflows ◽

Chemical Models ◽

Cloud Complex

Abstract Using the new equipment of the Shanghai Tian Ma Radio Telescope, we have searched for carbon-chain molecules (CCMs) towards five outflow sources and six Lupus I starless dust cores, including one region known to be characterized by warm carbon-chain chemistry (WCCC), Lupus I-1 (IRAS 15398-3359), and one TMC-1 like cloud, Lupus I-6 (Lupus-1A). Lines of HC3N J = 2 − 1, HC5N J = 6 − 5, HC7N J = 14 − 13, 15 − 14, 16 − 15, and C3S J = 3 − 2 were detected in all the targets except in the outflow source L1660 and the starless dust core Lupus I-3/4. The column densities of nitrogen-bearing species range from 1012 to 1014 cm−2 and those of C3S are about 1012 cm−2. Two outflow sources, I20582+7724 and L1221, could be identified as new carbon-chain-producing regions. Four of the Lupus I dust cores are newly identified as early quiescent and dark carbon-chain-producing regions similar to Lup I-6, which together with the WCCC source, Lup I-1, indicate that carbon-chain-producing regions are popular in Lupus I which can be regard as a Taurus-like molecular cloud complex in our Galaxy. The column densities of C3S are larger than those of HC7N in the three outflow sources I20582, L1221, and L1251A. Shocked carbon-chain chemistry is proposed to explain the abnormal high abundances of C3S compared with those of nitrogen-bearing CCMs. Gas-grain chemical models support the idea that shocks can fuel the environment of those sources with enough S+ thus driving the generation of S-bearing CCMs.

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