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The texture of sausage was affected by its binding agent. Elephant foot yam (Amorphophallus campanulatus) flour was a potential natural binding agent and filler for sausage. The objective of this study was to evaluate the effect of elephant foot yam flour and soybean oil addition to the physicochemical properties and sensory attributes of beef sausage. A randomized block design with two factors and three replications were employed. Three addition levels (10%, 15% and 20% of meat weight) were used for both elephant foot yam flour and soybean oil. The results showed that the addition of elephant foot yam flour significantly (P≤0.01) affect the water-holding capacity (WHC) and sausage texture. The effect (P≤0.05) was also observed on the redness color (a* value). However, no effect was found on pH, L and b* values. On the other hand, the WHC and sausage texture were also significantly (P≤0.05) affected by soybean oil addition without altering pH and color. The highest addition level (20%) for both elephant foot yam flour and soybean oil showed a firm and compact beef sausage micro-structure with small pores. The highest fat and crude fiber content were also found in this group (20% addition level) and the sensory attributes (texture, aroma and taste) of the former group were comparable with the group with lowest addition level (10%). Therefore, elephant foot yam flour can be used as filler for producing both reduced-fat and typical beef sausage.

In this study, we investigated the effects of different high-intensity ultrasound (HIU) pretreatment times (0–60 min) on the structure of β-conglycinin (7S) and the structural and functional properties of 7S gels induced by transglutaminase (TGase). Analysis of 7S conformation revealed that 30 min HIU pretreatment significantly induced the unfolding of the 7S structure, with the smallest particle size (97.59 nm), the highest surface hydrophobicity (51.42), and the lowering and raising of the content of the α-helix and β-sheet, respectively. Gel solubility showed that HIU facilitated the formation of ε-(γ-glutamyl)lysine isopeptide bonds, which maintain the stability and integrity of the gel network. The SEM revealed that the three-dimensional network structure of the gel at 30 min exhibited filamentous and homogeneous properties. Among them, the gel strength and water-holding capacity were approximately 1.54 and 1.23 times higher than those of the untreated 7S gels, respectively. The 7S gel obtained the highest thermal denaturation temperature (89.39 °C), G′, and G″, and the lowest tan δ. Correlation analysis demonstrated that the gel functional properties were negatively correlated with particle size and the α-helix, while positively with Ho and β-sheet. By contrast, gels without sonication or with excessive pretreatment showed a large pore size and inhomogeneous gel network, and poor properties. These results will provide a theoretical basis for the optimization of HIU pretreatment conditions during TGase-induced 7S gel formation, to improve gelling properties.

The present work investigated the effects of water bath heating coupled with different ultrasound treatments on the gel properties, protein conformation, microstructures and chemical interactions of silver carp surimi at low/high salt levels. Results showed that the gel strength, hardness, springiness and water holding capacity (WHC) of surimi gels at low salt concentration were inferior to those at high salt content, regardless of the treatments. Compared with the traditional water bath heating, ultrasonic-assisted treatments significantly improved the gelation properties of surimi at the same salt level. In fact, ultrasound treatment also facilitated the unfolding of α-helix structure of the protein, with the resulting exposure of internal groups further enhancing hydrophobic interactions and hydrogen bonds between protein molecules, thereby leading to the formation of denser microstructures with smaller holes. Furthermore, the most noteworthy ultrasonic treatment group was ultrasound-assisted preheating (U + W) group, whose gelation performance under low salt condition, was comparable with that of the traditional two-stage heating (W + W) group with high salt content. Overall, ultrasound-assisted water bath preheating proved to be a feasible approach to improve the gel properties and microstructures of low-salt surimi gels.

Silver carp (Hypophthalmichthys molitrix) is a potential source for making surimi products. However, it has the disadvantages of bony structures, high level of cathepsines and muddy off-odor which is mainly caused by geosmin (GEO) and 2-methylisoborneol (MIB). These disadvantages make the conventional water washing process of surimi inefficient (low protein recovery rate, and high residual muddy off-odor). Thus, the effect of the pH-shifting process (acid-isolating process and alkali-isolating process) on the cathepsins activity, GEO content, MIB content, and gelling properties of the isolated proteins (IPs) was investigated, comparing it with surimi obtained through the conventional cold water washing process (WM). The alkali-isolating process greatly boosted the protein recovery rate from 28.8% to 40.9% (p < 0.05). In addition, it removed 84% GEO and 90% MIB. The acid-isolating process removed about 77% GEO and 83% MIB. The acid-isolated protein (AC) displayed the lowest elastic modulus (G′), the highest TCA-peptide content (90.89 ± 4.65 mg/g) and the highest cathepsin L activity (65.43 ± 4.91 U/g). The AC modori (60 °C for 30 min) gel also demonstrated the lowest breaking force (226.2 ± 19.5 g) and breaking deformation (8.3 ± 0.4 mm), indicating that proteolysis caused by the cathepsin deteriorated the gel quality of AC. The setting (40 °C for 30 min) considerably increased the breaking force (386.4 ± 15.7 g) and breaking deformation (11.6 ± 0.2 mm) of the gel made from the alkali-isolated protein (AK) (p < 0.05). In AC and AK gel, a clearly visible cross-linking protein band with a molecular weight greater than MHC was seen, demonstrating the presence of endogenous trans-glutaminase (TGase) activity, that improved the gel quality of AK. In conclusion, the alkali-isolating process was an effective alternative method for making water-washed surimi from silver carp.

Руськина Алена Александровна, старший преподаватель кафедры «Пищевые и биотехнологии», Южно-Уральский государственный университет (г. Челябинск), ruskinааа@susu.ru. Калинина Ирина Валерьевна, доктор технических наук, профессор кафедры «Пищевых и биотехнологий», Южно-Уральский государственный университет (г. Челябинск), kalininaiv@susu.ru. Попова Наталия Викторовна, кандидат технических наук, доцент кафедры «Пищевые и биотехно-логии», Южно-Уральский государственный университет (г. Челябинск) nvpopova@susu.ru. Ураканова Аделия Альбертовна, студент кафедры «Пищевые и биотехнологии», Южно-Уральский государственный университет (г. Челябинск). Девяткин Дмитрий Иванович, студент кафедры «Пищевые и биотехнологии», Южно-Уральский государственный университет (г. Челябинск). Alena A. Ruskina, Senior Academic at the Department of Food Technology and Biotechnology, South Ural State University, Chelyabinsk, ruskina_a@mail.ru Irina V. Kalinina, doctor of technical sciences, professor of the department of food technology and biotechnology, South Ural State University, Chelyabinsk, kalininaiv@susu.ru Natalia V. Popova, Candidate of Sciences (Engineering), Associate Professor, South Ural State University, Chelyabinsk, nvpopova@susu.ru Adelia A. Urakanova, student of the Department of Food and Biotechnology, South Ural State University (Chelyabinsk). Dmitry I. Devyatkin,student of the Department of Food and Biotechnology, South Ural State University (Chelyabinsk). В последнее время актуальным направлением исследований ученых является разработка методов модификации растительных полисахаридов и прежде всего крахмала, с целью регулирования технологической пригодности и установление возможности его применения в производстве продуктов питания. Целью данной работы является разработка технологии желейных кондитерских изделий на примере получения мармелада, в рецептуре которого в качестве студнеобразователя использовался сонохимически модифицированный картофельный крахмал, и оценка потребительских свойств полученных изделий. В данном исследовании был использован крахмал картофельный, модифицированный с применением низкочастотного ультразвука по методике патента РФ № 2708557 «Способ производства модифицированного крахмала». Применение крахмала в производстве мармелада ограничено, так как студни, полученные из нативного крахмала, плохо формуются, а также склонны к ретроградации. Полученные образцы мармелада оценивали по номенклатуре показателей, включающих органолептические и реологические свойства. По органолептическим показателям мармелад на основе модифицированного крахмала не уступал традиционным образцам, а по вкусу даже превосходил их. По физико-химическим показателям разработанный образец мармелада соответствовал требованиям ГОСТ 6442–2014 «Мармелад. Технические условия», значительных отличий от традиционных образцов отмечено не было. Исключение составил показатель массовая доля редуцирующих веществ, значение которого для разработанного образца мармелада было выше на 25–40 % в сравнении с традиционными образцами. Анализ реологических характеристик образцов мармелада проводили на приборе «Структурометр СТ-2», который позволил установить прочность мармеладного студня в изломе. Результаты исследования реологических свойств образцов показали, что самая высокая прочность в изломе была у образца мармелада на агар-агаре, самая низкая – у образца на желатине. Прочность мармелада на основе модифицированного крахмала составила 90 г, что было на 13 % выше, чем у образца мармелада на желатине. Полученные в ходе исследования данные свидетельствуют о том, что применение модифицированного крах-мала как студнеобразователя при производстве мармелада обоснованно и может составлять интерес как для дальнейших исследований, так и для внедрения в реальное производство. Recently, an urgent area of research of scientists is the development of methods for modifying plant polysaccharides and, above all, starch, in order to regulate the technological suitability and establish the possibility of its use in food production. The purpose of this work is to develop the technology of jelly confectionery products on the example of obtaining marmalade, in the reci-pe of which sonochemically modified potato starch was used as a jelly-forming agent, and to eval-uate the consumer properties of the obtained products. In this study, potato starch was used, modi-fied with the use of lowfrequency ultrasound according to the method of RF patent No. 2708557 "Method of production of modified starch". The use of starch in the production of marmalade is limited, since jellies obtained from native starch are poorly formed, and are also prone to retrogradation. The obtained marmalade samples were evaluated according to the nomenclature of indicators, including organoleptic and rheological properties. According to organoleptic indicators, the marmalade based on modified starch was not inferior to traditional samples, and even sur-passed them in taste. According to physical and chemical parameters, the developed sample of marmalade met the requirements of GOST 6442–2014 "Marmalade. Technical conditions", no significant differences from traditional samples were noted. The exception was the indicator mass fraction of reducing substances, the value of which for the developed sample of marmalade was higher by 25–40 % in comparison with traditional samples. The analysis of the rheological charac-teristics of the marmalade samples was carried out on the device "Structurometer ST-2", which al-lowed to establish the strength of the marmalade jelly in the fracture. The results of the study of the rheological properties of the samples showed that the highest fracture strength was in the sam-ple of marmalade on agar-agar, the lowest in the sample on gelatin. The strength of the marmalade based on modified starch was 90 g, which was 13 % higher than that of the sample of marmalade on gelatin. The data obtained in the course of the study indicate that the use of modified starch as a jelly-forming agent in the production of marmalade is justified and may be of interest both for further research and for implementation in real production.

The effects of subunit composition of two major proteins of soybean: glycinin (11S) and -conglycinin (7S) in nine different genotypes, on solubility and emulsifying and gelling properties at different pH (3, 5, 6, and 8) were examined. High-protein genotypes (more than 40%) contained low amounts of the subunit. The main factors influencing solubility at pH 6 were the content of , (r = 0.89 and r = 0.91 at P lt 0.05, respectively) and subunit contents (r = -0.71 at P lt 0.05) of -conglycinin, while at pH 3 acidic subunits in glycinin had a positive correlation with solubility (r = 0.69 at P lt 0.05). Emulsion activity at pH 6 was higher for genotypes synthesizing subunit (r = 0.57 at P lt 0.05). Genotypes synthesizing higher amounts of and subunit had higher emulsion stability at pH 6 (r = 0.85 and r = 0.92 at P lt 0.05, respectively) and pH 8 (r = 0.91 and r = 0.97 at P lt 0.05, respectively). The rheological measurements showed that genotypes with 11S/7S ratio higher than 2.2 formed gels with enhanced storage moduli. This influence was largely due to the high content of SH groups in glycinin acidic polypeptides resulting in stabilization of gels via disulfide bonding. Gels prepared from genotypes containing higher amounts of subunit of -conglycinin exhibited reduced elastic properties. Genotypes showing better solubility also had higher emulsion stability, but formed weaker gels and had lower emulsion activity near neutral pH.

Background Rye arabinoxylans (AXs) might be used as baking improvers for gluten-free (GF) bread. However, their extraction process still needs to be improved. Objective and methods The aim of this study was to simplify AX extraction of rye bran by varying temperature and pH and evaluate its chemical and rheological properties for application in GF bread. Results and conclusion The results demonstrated that higher amounts of AX and impurities were extracted with the increasing pH and temperature. AX yield reached values up to 3.3 g AX/100 g bran. Highest ferulic acid (FA) content (117.27 ± 1.46 mg/100 g) was achieved at the mildest extraction conditions (30 °C and 0.17 M NaOH). A/X ratio of isolates ranged between 0.53 and 0.57 and the gluten content between 81.30 and 216.78 ppm. Rheological measurements revealed typical pseudoplastic behavior of isolates. AX extracted at 30 °C and 0.17 M NaOH showed a slightly higher initial viscosity in comparison with the other isolates but was still inferior to carboxylmethylcellulose (CMC) and hydroxypropyl methylcellulose (HPMC). Graphical abstract Influence of the process parameters on the extraction and properties of arabinoxylans from rye bran.

A consolidation technique based on gelling property of starch was used to prepare alumina ceramics. Slurry containing alumina powder, dispersant and small amount of starch (2-3.5 wt.% of powder weight) was cast into a nonporous mould and heated to gelation temperature to produce a rigid green body. A defect free green body was obtained and the total linear shrinkage during drying was 2-3% and the green density observed was 64% of theoretical value. After complete drying, ceramic compacts were sintered without debinding operation. Sintered density of 99.4% was achieved after sintering at 1600 �C for 2 h. Flexural strength values of dried and sintered alumina were ?10 and 247 MPa, respectively. The sintered ceramics showed an extremely dense microstructure. � 2009 Elsevier Ltd. All rights reserved.

International audience; Dry-heating is considered to be one of the most promising approaches to improving the functionality of food proteins. It has been shown that even if only minor structural modifications occur during dry-heating, the foaming properties of proteins are highly improved. With the recent results obtained in the field of foam stabilization by nanoparticles or protein aggregates in mind, a study was undertaken on the impact of dry-heating of lysozyme, used as a model protein, on its foaming properties. This work highlighted the fact that dry-heated hen egg white lysozyme simultaneously exhibited enhanced foaming properties and aggregation capacity. Although the conditions that favored bulk aggregation (high ionic strength, pH, treatment duration, and protein concentration) also favored foaming properties, the large bulk aggregates were not essential to obtain the best functionality. It is envisaged that heat-treated lysozyme may self-associate at the air/water interface, stabilizing air bubbles.