Technology of Quick-Frozen Flour Fish Culinary Products

In this article, the results of the development of the functional fish culinary product “Thorny Skate and Cod Pie” are presented. A traditional recipe was used for making the yeast dough for the pie. The pie filling recipe was designed using Fuzzy Logic in the Matlab software package.Optimized parametersfor the selected sensory evaluation of the pie were calculated. On the basis of a priori information, key components of the filling (including the fraction of the fish components and skate meat) were chosen as the factors of interest. According to the simulation results, the optimal values werea 50/50 percentage for the first and the second factor respectively, and this providedthe maximum organoleptic assessment (five points on a five-point scale). The simulation results were compared with the results of the organoleptic evaluation of the pie made according to the optimized recipe, and their sufficient convergence was shown. The indicators of mass fraction of amine nitrogen and nitrogen of volatile bases was studied, as well as the microbiological safety indicators of flour fish culinary products, in accordance with the requirements of the Technical Regulations of the Eurasian Economic Union 040/2016 ”On the safety of fish products”. The results showed a high efficiency of the shock freezing of the semi-finished product, brought to semi-readiness, for long-term storage (120 days at a temperature no higher than minus 18 ∘C), without reducing the quality or safety of the pie. The product had a cholesterol content from 220 to 260 mg%, which allowed it to be classified as functional. The nutritional values of the product (mass fraction of protein, fat, carbohydrates, and amino acid composition) are presented. Keywords: thornyskate, functional product, pie with thornyskate and cod, shock freezing

Role of Nitrogen Compounds in Forming the Quality of Red Sparkling Wine

В технологии игристых вин азотистые соединения, в том числе их концентрация и качественный состав, играют существенную роль на всех этапах производственного процесса. Цель работы состояла в исследовании изменения азотсодержащих соединений в процессе вторичного брожения и их влияния на качественные характеристики красного игристого вина. В качестве объектов исследования в работе использованы пять промышленных образцов сортовых виноматериалов, соответствующих требованиям нормативной документации по физико-химическим и органолептическим показателям, и пять купажей, составленных из этих виноматериалов, а также опытные образцы игристых вин, полученные в результате вторичного брожения в бутылках. Определение массовой концентрации аминного азота проводили методом йодометрического титрования, аммиачного азота - диффузионным методом. Исследование качественного состава и концентрации аминокислот проводили с использованием ВЭЖХ на приборе «Аgilent Technologies 1200 Series» (Agilent, США). Установлено, что концентрация аммиачного азота в исследованных образцах варьировала от 13,4 до 29,7 мг/дм3, аминного азота - от 53,2 до 364,0 мг/дм3, свободных аминокислот - от 267,4 до 615,4 мг/дм3. Показано, что в результате вторичного брожения снижается суммарная концентрация аминокислот, причем наиболее сильно - в образцах с низким содержанием неорганического азота менее 20,0 мг/дм3. В образцах с высоким содержанием фенольных веществ снижение концентрации аминокислот происходило за счет образования с ними комплексных соединений. Показано, что состав азотистых соединений и соотношение свободных аминокислот в исходных виноматериалах оказывает влияние на образование отдельных ароматобразующих летучих компонентов и формирование типичных свойств красного игристого вина. Рекомендовано использовать показатели массовой концентрации аминного и аммиачного азота, а также состав и концентрацию свободных аминокислот в качестве дополнительных критериев оценки виноматериалов для выработки высококачественных красных игристых вин. In the technology of sparkling wines, nitrogenous compounds, including their concentration and qualitative composition, play an essential role at all stages of the production process. The aim of the work was to study the changes in nitrogen-containing compounds during secondary fermentation and their effect on the qualitative characteristics of red sparkling wine. As objects of research, five industrial samples of varietal wine materials that meet the requirements of regulatory documentation on physico-chemical and organoleptic indicators, and five blends made up of these wine materials, as well as experimental samples of sparkling wines obtained as a result of secondary fermentation in bottles, were used in the work. Determination of the mass concentration of amine nitrogen was carried out by iodometric titration, ammonia nitrogen - by diffusion method. The study of the qualitative composition and concentration of amino acids was carried out using HPLC on the device «Agilent Technologies 1200 Series» (Agilent, USA). It was found that the concentration of ammonia nitrogen in the studied samples varied from 13.4 to 29.7 mg/dm3, amine nitrogen - from 53.2 to 364.0 mg/dm3, free amino acids - from 267.4 to 615.4 mg/dm3. It is shown that as a result of secondary fermentation, the total concentration of amino acids decreases, and most strongly in samples with a low content of inorganic nitrogen less than 20.0 mg /dm3. In samples with a high content of phenolic substances, the concentration of amino acids decreased due to the formation of complex compounds with them. It is shown that the composition of nitrogenous compounds and the ratio of free amino acids in the initial wine materials influence the formation of individual aroma-forming volatile components and the formation of typical properties of red sparkling wine. It is recommended to use indicators of the mass concentration of amine and ammonia nitrogen, as well as the composition and concentration of free amino acids as additional criteria for evaluating wine materials for the production of high-quality red sparkling wines.

Comparison of effectiveness of various bacterial proteases preparations in collagen hydrolysis

Гидролизаты коллагена широко используются в пищевой, фармацевтической и косметической промышленности. Для обработки коллагена используют различные протеолитические ферменты растительного, животного и микробного происхождения, из которых самыми перспективными являются бактериальные протеазы. Наиболее известные и часто используемые в пищевой отрасли коммерческие препараты бактериальных протеаз различаются по компонентному составу и могут содержать сериновые, металлопротеазы либо их смесь. С целью определения эффективности препаратов бактериальных протеаз с различным компонентным составом при получении гидролизатов коллагена мы провели ферментативную обработку говяжьего коллагена с использованием коммерческих препаратов Alcalase, Neutrase, Protamex и двух образцов ферментных препаратов, полученных в лабораторных условиях на основе новых отечественных штаммов Bacillus. Эффективность гидролиза оценивали по накоплению аминного азота, содержанию низкомолекулярного белка и по интенсивности белковых полос на электрофореграммах полученных продуктов. Все исследуемые препараты обеспечивали эффективный гидролиз коллагена. Наиболее интенсивно коллаген расщепляли препараты, содержащие только сериновые протеазы: Alcalase и ФП-145, полученный из культуральной жидкости штамма B. licheniformis-145. Высокую эффективность показали коммерческий препарат Protamex и ФП-96, полученный на основе мутантного варианта штамма B. subtilis-359 - продуцента субтилизина BPN’ и бациллолизина. Наименьший выход аминного азота и низкомолекулярных белков наблюдался в варианте с препаратом Neutrase, протеолитическая активность которого полностью представлена действием нейтральной протеазы бациллолизина. Лабораторные образцы ферментных препаратов, полученные на основе новых отечественных продуцентов, не уступали зарубежным коммерческим аналогам, а ФП-96 обеспечил более высокий выход аминного азота и низкомолекулярных белков в сравнении с широко используемым в пищевой промышленности препаратом Protamex. Collagen hydrolysates are widely used in the food, pharmaceutical and cosmetic industries. For collagen hydrolysis, various proteolytic enzymes of plant, animal and microbial origin are used, of which the most promising are bacterial proteases. The most well-known and commonly used in the food industry commercial preparations of bacterial proteases differ in their component composition and may contain serine protease, metalloproteases, or their mixture. In order to determine the effectiveness of bacterial protease preparations with different component composition in obtaining collagen hydrolysates, we carried out hydrolysis of beef collagen using commercial preparations Alcalase, Neutrase, Protamex and two laboratory samples of enzyme preparations obtained from new domestic Bacillus strains. The efficiency of hydrolysis was assessed by amine nitrogen accumulation, low-molecular-weight protein content, and by the intensity of the protein bands on the electrophoregrams of the hydrolysates. All investigated preparations provided effective collagen hydrolysis. Collagen was hydrolyzed most intensively by preparations containing only serine proteases: Alcalase and FP-145, obtained from B. licheniformis-145 culture liquid. The commercial preparation Protamex and FP-96, obtained from a mutant variant of the B. subtilis-359 strain, a producer of subtilisin BPN' and bacillolysin, showed high efficiency. The lowest yield of amine nitrogen and low molecular weight proteins was observed when using Neutrase, which contains only the neutral protease bacillolysin. Laboratory samples of enzyme preparations obtained from the new domestic producers were not inferior to foreign commercial counterparts, and FP-96 provided a higher yield of amine nitrogen and low molecular weight proteins in comparison with Protamex, which is widely used in the food industry.

Effect of nickel oxide nanoparticles on protease activity in brewing industry

Intensive use of nanoparticles on an industrial scale leads to an increase in their content in the environment. This increases the risks of nano-sized objects entering the technological chains of the processing industries of the agro-industrial complex, in particular, brewing. The paper presents the results of the studies of the effect of nickel oxide nanoparticles used in various industries on the activity of the proteolytic type of enzyme preparation Neutrase 1.5MG, as well as on the results of laboratory mashing of light barley malt. The effect of different concentrations of NiO nanoparticles on the accumulation of low molecular weight nitrogenous substances during gelatin hydrolysis in model media was determined. It was found that if the content of nanoparticles exceeds 0.25 mg/cm3, the proteolytic capacity of the enzyme preparation is reduced up to 70% compared to the control at the concentration of nickel oxide nanopreparation of 2.0 mg/cm3. The experiments showed that an increase in the duration of contact between nanoparticles and proteases of the enzyme preparation in the reaction medium did not lead to an increase in the inhibitory effect of the nano-sized NiO. The laboratory mashing revealed more pronounced negative effect of nickel oxide nanoparticles on the accumulation of low-molecular nitrogen compounds. It is determined that in the presence of NiO nanopreparation, the hydrolysis efficiency of the starchy components of light barley malt is reduced. As a result, according to a number of indicators (concentration of amine nitrogen, reducing substances), the first wort obtained by mashing in the presence of nickel oxide nanoparticles at both lower (0.25 mg/cm3) and higher (2.0 mg/cm3) concentrations is inferior to samples obtained in the absence of nano-sized particles. Based on the above data, it is concluded that the presence of NiO nanoparticles in brewing environments is undesirable.

Synthesis and absolute structure of (R)-2-(benzylselanyl)-1-phenylethanaminium hydrogen sulfate monohydrate: crystal structure and Hirshfeld surface analyses

A hydrogen sulfate salt, C15H18NSe+·HSO4 −·H2O or [BnSeCH2CH(Ph)NH3 +](HSO4 −), of a chiral selenated amine (R)-2-(benzylselanyl)-1-phenylethanamine (BnSeCH2CH(Ph)NH2) has been synthesized and characterized by elemental analysis,1H and 13C{1H} NMR, FT–IR analysis, and single-crystal X-ray diffraction studies. The title salt crystallizes in the monohydrate form in the non-centrosymmetric monoclinic P21 space group. The cation is somewhat W shaped with the dihedral angle between the two aromatic rings being 60.9 (4)°. The carbon atom attached to the amine nitrogen atom is chiral and in the R configuration, and, the –C—C– bond of the –CH2—CH– fragment has a staggered conformation. In the crystal structure, two HSO4 − anions and two water molecules form an R 4 4(12) tetrameric type of assembly comprised of alternating HSO4 − anions and water molecules via discrete D(2) O—H...O hydrogen bonds. This tetrameric assembly aggregates along the b-axis direction as an infinite one-dimensional tape. Adjacent tapes are interconnected via discrete D(2) N—H...O hydrogen bonds between the three amino hydrogen atoms of the cation sandwiched between the two tapes and the three HSO4 − anions of the nearest asymmetric units, resulting in a complex two-dimensional sheet along the ab plane. The pendant arrangement of the cations is stabilized by C—H...π interactions between adjacent cations running as chains down the [010] axis. Secondary Se...O [3.1474 (4) Å] interactions are also observed in the crystal structure. A Hirshfeld surface analysis, including d norm, shape-index and fingerprint plots of the cation, anion and solvent molecule, was carried out to confirm the presence of various interactions in the crystal structure.

Effect of process parameters of mashing on consumer properties and processability of polymalt extracts production process

The development of the technology of viscous polymalt extracts using bare-grained oats will provide the population with a functional food ingredient and products with specified consumer properties. Existing techniques for the production of extracts did not affect the study of temperature conditions and the duration of the process at the mashing stage, using bare-grained oats in its composition. Crops of Belarusian breeding were used as raw materials: barley (H. vulgare), bare-grained oats (A. sativa), wheat (Tr. aestivum) grain. Optimization of parameters in the production of polymalt wort based on barley, oat and wheat malt was carried out by regression analysis and weight coefficients. Dependencies of physico-chemical indices of oat-malt and polymalt worts on temperature and duration of mashing are established. These dependencies predict content of dry substances, maltose, amine nitrogen, protein and acidity in the process of production of worts. Optimal technological parameters were selected at the stage of barley-wheat-oat polymalt wort mashing, which made it possible to increase the dry substances by 12.5%, maltose – by 21.3%, protein – by 16.2% and filtration rate – by 25.0%. The maximum solid content 14.4%, maltose 11.4 g·(100·сm-3)-1, protein 1.22%, in polymalt wort achieved under the following modes: (3 ±1)°C for 30 minutes, (44±1)°C for 50 minutes, (53±1)°C for 60 minutes, (63±1)°C for 50 minutes, (72±1)°C for 20 minutes and (78±1)°C for 60 minutes.

Selecting multi-enzyme composition and preparation conditions for strong wort

Development of sustainable biotechnologies for deep processing of grain raw materials requires effective mechanisms of obtaining strong wort for alcohol production. To provide qualitative characteristics of biochemical composition and rheological properties of strong wort, it is necessary to select optimal enzyme systems and conditions for deep conversion of high-molecular weight polymers of the grain. Previous research has proven the efficiency of carbohydrases for processing grain raw materials. However, there is little evidence on the catalytic effect of phytase, including in combination with other hydrolytic enzymes, on the degree of hydrolysis of polymers in grain raw materials when preparing strong wort. This paper demonstrates the effect of proteases and phytases in a multi-enzyme composition, as well as the conditions of enzymatic processing of raw materials, on the rheological and biochemical parameters of strong wort. Wheat, rye and corn were investigated. The synergism of the combined effect of studied hydrolases, including phytolytic and proteolytic enzymes, contributed to an increase in polymer conversion in this grain raw material and the concentration of soluble dry substances of the wort by 1.5 times. Using the proteases and phytases in the multienzyme composition allowed the concentration of the following components in the wort to be increased: glucose – by 1.2–1.3 times; amine nitrogen – by 1.5–2.2 times; phosphorus ions – by 1.4–4.3 times. Additionally, in the wort samples, the content of amino acids in the free form increased by over 4 times. It is shown that the pretreatment of grain raw materials at a temperature of 80–90ºС for 6 hours and saccharification for 1–2 hours using a complete complex of enzymes containing α-amylase, glucoamylase, xylanase, protease and phytase, allows a strong wort with a dry matter content of over 30% to be obtained. Moreover, a significant decrease in viscosity was noted (particularly for rye wort – by 1.3–1.9 times). Our results confirm the essential role of enzymes exhibiting substrate specificity to protein and phytic polymers in grain raw materials.

Geometrical variations of two manganese(II) complexes with closely related quinoline-based tripodal ligands

Structural analyses of the compounds di-μ-acetato-κ4 O:O′-bis{[2-methoxy-N,N-bis(quinolin-2-ylmethyl)ethanamine-κ4 N,N′,N′′,O]manganese(II)} bis(tetraphenylborate) dichloromethane 1.45-solvate, [Mn2(C23O2)2(C23H23N3O)2](C24H20B)·1.45CH2Cl2 or [Mn(DQMEA)(μ-OAc)2Mn(DQMEA)](BPh4)2·1.45CH2Cl2 or [1](BPh4)2·1.45CH2Cl2, and (acetato-κO)[2-hydroxy-N,N-bis(quinolin-2-ylmethyl)ethanamine-κ4 N,N′,N′′,O](methanol-κO)manganese(II) tetraphenylborate methanol monosolvate, [Mn(CH3COO)(C22H21N3O)(CH3OH)](C24H20B)·CH3OH or [Mn(DQEA)(OAc)(CH3OH)]BPh4·CH3OH or [2]BPh4·CH3OH, by single-crystal X-ray diffraction reveal distinct differences in the geometry of coordination of the tripodal DQEA and DQMEA ligands to MnII ions. In the asymmetric unit, compound [1](BPh4)2·(CH2Cl2)1.45 crystallizes as a dimer in which each manganese(II) center is coordinated by the central amine nitrogen, the nitrogen atom of each quinoline group, and the methoxy-oxygen of the tetradentate DQMEA ligand, and two bridging-acetate oxygen atoms. The symmetric MnII centers have a distorted, octahedral geometry in which the quinoline nitrogen atoms are trans to each other resulting in co-planarity of the quinoline rings. For each MnII center, a coordinated acetate oxygen participates in C—H...O hydrogen-bonding interactions with the two quinolyl moieties, further stabilizing the trans structure. Within the crystal, weak π–π stacking interactions and intermolecular cation–anion interactions stabilize the crystal packing. In the asymmetric unit, compound [2]BPh4·CH3OH crystallizes as a monomer in which the manganese(II) ion is coordinated to the central nitrogen, the nitrogen atom of each quinoline group, and the alcohol oxygen of the tetradentate DQEA ligand, an oxygen atom of OAc, and the oxygen atom of a methanol ligand. The geometry of the MnII center in [2]BPh4·CH3OH is also a distorted octahedron, but the quinoline nitrogen atoms are cis to each other in this structure. Hydrogen bonding between the acetate oxygen atoms and hydroxyl (O—H...O) and quinolyl (C—H...O and N—H...O) moieties of the DQEA ligand stabilize the complex in this cis configuration. Within the crystal, dimerization of complexes occurs by the formation of a pair of intermolecular O3—H3...O2 hydrogen bonds between the coordinated hydroxyl oxygen of the DQEA ligand of one complex and an acetate oxygen of another. Additional hydrogen-bonding and intermolecular cation–anion interactions contribute to the crystal packing.

Synthesis and Aggregation of Novel Sugar-based Gemini Surfactants in Aqueous Solution

Novel sugar-based gemini surfactants with a 1,3-propan-2-ol spacer (1, 3-(N- alkyl-2-D-glucosaminyl acetyl) propan-2-ol, Glu(n)-3(OH)-Glu(n), n = 12, 14) were synthesized with D-(+)-glucono-1,5-lactone as starting material in two steps, whose structures were confirmed using proton nuclear magnetic resonance spectroscopy (1H NMR) and carbon nuclear magnetic resonance carbon spectroscopy (13C NMR). The micellization of Glu(n)-3(OH)-Glu(n) (n = 12, 14) in aqueous solution at 25.0°C was investigated by using surface tension measurement. The results show that the critical micelle concentration (CMC) of Glu(12)-3(OH)-Glu(12) is around 10–5 mol × L–1, and is one order of magnitude smaller than that of Glu(14)-3(OH)-Glu(14), indicating that the surface activity of Glu(12)-3(OH)-Glu(12) is superior to that of Glu(14)-3(OH)-Glu(14). Moreover, the aggregation behavior of Glu(12)-3(OH)-Glu(12) in aqueous solution at different pH values was investigated by surface tension, dynamic light scattering (DLS), and cryogenic transmission electron microscopic (Cryo-TEM) measurements. The results indicate that the CMC slightly increases with the decrease of the solution pH. The microstructure of Glu(12)-3(OH)-Glu(12) aggregates transitions from micelle to vesicle with the solution pH from acidic to neutral and alkaline. The microstructural transformation of Glu(12)-3(OH)-Glu(12) with the solution pH is mainly determined by the protonation of the two tertiary amine nitrogen atoms in its hydrophilic headgroups.

Influences of Chemical Functionalities on Crystal Structures and Electrochemical Properties of Dihydro-benzoxazine Dimer Derivatives

Dihydro-1,3,2H-benzoxazine dimer derivatives or dihydro-benzoxazine dimers are a class of compounds typically prepared by ring-opening reactions between dihydro-benzoxazines and phenols. Dihydro-benzoxazine dimers act as chelating agents for several transition and rare-earth cations. To better understand the chelating properties, it is necessary to examine their structural features and electrochemical characteristics thoroughly. However, the electrochemical properties of dihydro-benzoxazine dimers have not been tremendously examined. Herein, eight derivatives of dihydro-benzoxazine dimers possessing different substituents on the benzene ring and the tertiary-amine nitrogen were synthesized as model compounds to investigate their influences on crystal structures and electrochemical properties. The crystal structure of the dihydro-benzoxazine dimer, namely 2,2’-(cyclohexylazanediyl)bis(methylene)bis(4-methoxyphenol) (7), is identified for the first time and further used to compare with the crystal structures of other derivatives reported previously. For all the derivatives, intermolecular O–H···O hydrogen bonds are the significant interactions to hold the crystal packing of (7) and also the other derivatives. Hirshfeld surface analyses confirm the presence of intermolecular O–H···O hydrogen bonds. Redox behavior of the eight dihydro-benzoxazine dimers was studied by cyclic voltammetry. An oxidation peak observed at 0.25–0.47 V corresponds to the oxidation of the phenolic –OH group to the phenoxonium intermediate. The shift in the electrochemical peak positions is due to the different abilities of the substituents to stabilize the phenoxonium cation intermediate. The stabilizing power is ranged in the following order: methoxy > dimethyl > ethyl ≈ methyl, and N-cyclohexyl > N-methyl. Thus, the derivative (7), which contains both the methoxy and N-cyclohexyl groups, has the lowest oxidation potential. Our work elucidates the effect of the substituents on the crystal structures and electrochemical properties of the dihydro-benzoxazine dimers.