High-temperature Hydrolysis Research Articles

Obtaining and estimating the potential of protein nutraceuticals from highly mineralized collagen-containing beef raw materials

Highly mineralized collagen-containing beef raw materials (tibia, fibula and costal bones) are a source of valuable protein nutraceuticals. They include high molecular weight proteins, oligopeptides and amino acids, which anabolic and physiological potential is used insufficiently. Protein nutraceuticals were obtained by high-temperature hydrolysis of beef raw materials in combination with enzymolysis by proteolytic enzyme preparations Alcalase 2,5 L, Protamex, Protosubtilin G3x. The water-soluble fraction of hydrolysates was studied after its separation and freeze-drying on the content of nitrogenous compounds, fats, minerals, formol-titrated nitrogen, fractional molecular composition. The mathematical dependencies of accumulation of low molecular weight products of protein hydrolysis on enzymolysis duration and doses of different enzyme preparations were obtained. The rational technological scheme of complex processing of beef raw materials with production of protein, fat and mineral-protein additives was proposed. The protein weight fraction in the freeze-dried protein hydrolysates was 69.5–89.6%. All studied protein additives contained peptides with a molecular weight of not more than 100 kDa. The content of low-molecular weight oligopeptides with a molecular weight of less than 10 kDa in the protein additives obtained by enzymatic thermal hydrolysis was more than 90%. The amino acid composition of protein additives produced by different hydrolytic methods was analyzed. Sensory and functional-technological properties of freeze-dried protein compositions were studied. The amino acid potential, high assimilability and physiological activity of protein nutraceuticals from collagen-containing beef raw materials were established. It is recommended to use them in the composition of specialized biologically active additives (BAAs) to food of the osteotropic direction in recipes of specialized and personalized products as a source of amino acids and active peptides.

Free radical scavenging activity of type II collagen peptides and chondroitin sulfate oligosaccharides from by-products of mottled skate processing

The by-products of the skate processing industry have bioactive properties but are mostly discarded. In the present study, the properties of skate cartilage, a major by-product of skate processing that is rich in chondroitin sulfate (CS) and type II collagen were investigated. Enzymatically-hydrolyzed type II collagen peptides (CP) and thermally hydrolyzed CS oligosaccharides (CSo) from skate cartilage were prepared and their antioxidant activities were studied. High free radical scavenging activity was observed in the <3 kDa MW fraction of the papain hydrolyzed CP (Pa-CP). CSo also had high free radical scavenging activity, but the activity was mainly due to the intermediate and final products of the non-enzymatic browning reaction resulting from high-temperature hydrolysis. These products may have included flavonoid-like compounds. Furthermore, Pa-CP and CSo were not cytotoxic. Thus, Pa-CP and CSo derived from skate by-products may be beneficial antioxidant ingredients. The present study may contribute to the development of functional health foods and achieving zero-waste skate processing.

Specialized diet based on modified collagen-containing fish tissue

The study addresses the issue of complex processing of collagen-containing fish raw materials, and expansion of the range of specialized fish products of osteotropic action such as biocrips and protein bars. Small Baltic bream and heads of Baltic sprat, by-product of canned sprat production, were used as raw materials. The raw materials were pre-modified by high-temperature hydrolysis to break down collagen-containing connective tissues and soften bone tissues. Hydrolysis was performed in a thermoreactor in an aqueous medium at 120-40 °C, under pressure of 0.15 to 0.20 MPa within 60–90 minutes. Heat-treated raw materials were divided into fractions, which were used in specialized product processing. Chemical composition of raw materials and finished products was investigated. The technology of biocripts based on thermally modified muscle tissues of Baltic bream and bone supplement from its bones has been proposed. The formulation and technology of molded bars based on sublimated water-soluble protein fractions and a protein-mineral supplement made from heat-treated heads of Baltic sprat are substantiated. The functionality of the products in terms of the mineral content is shown. Recommendations for the use of specialized products for groups of people with deficiency of calcium, phosphorus, for sports and gerodietetic nutrition are elaborated.

Advanced Real-Time Process Analytics for Multistep Synthesis in Continuous Flow*.

In multistep continuous flow chemistry, studying complex reaction mixtures in real time is a significant challenge, but provides an opportunity to enhance reaction understanding and control. We report the integration of four complementary process analytical technology tools (NMR, UV/Vis, IR and UHPLC) in the multistep synthesis of an active pharmaceutical ingredient, mesalazine. This synthetic route exploits flow processing for nitration, high temperature hydrolysis and hydrogenation reactions, as well as three inline separations. Advanced data analysis models were developed (indirect hard modeling, deep learning and partial least squares regression), to quantify the desired products, intermediates and impurities in real time, at multiple points along the synthetic pathway. The capabilities of the system have been demonstrated by operating both steady state and dynamic experiments and represents a significant step forward in data‐driven continuous flow synthesis.

Advanced Real‐Time Process Analytics for Multistep Synthesis in Continuous Flow**

AbstractIn multistep continuous flow chemistry, studying complex reaction mixtures in real time is a significant challenge, but provides an opportunity to enhance reaction understanding and control. We report the integration of four complementary process analytical technology tools (NMR, UV/Vis, IR and UHPLC) in the multistep synthesis of an active pharmaceutical ingredient, mesalazine. This synthetic route exploits flow processing for nitration, high temperature hydrolysis and hydrogenation reactions, as well as three inline separations. Advanced data analysis models were developed (indirect hard modeling, deep learning and partial least squares regression), to quantify the desired products, intermediates and impurities in real time, at multiple points along the synthetic pathway. The capabilities of the system have been demonstrated by operating both steady state and dynamic experiments and represents a significant step forward in data‐driven continuous flow synthesis.

New methods of acid hydrolysis of cellulose and plant raw materials

Prospects for the development of hydrolysis production are determined by the relevance of industrial use of plant biomass to replace the declining reserves of fossil organic raw materials and increasing demand for ethanol, especially for its use as automobile fuel, protein-containing feed additives that compensate for protein deficiency in feed production, and other products. Based on the review of the research results presented in the scientific literature, the analysis of modern methods of liquid-phase acid hydrolysis of cellulose and various types of plant raw materials, including those that differ from traditional ones, is performed. The main directions of increasing its efficiency through the use of new catalytic systems and process conditions are identified. It is shown that the most promising methods for obtaining monosaccharides in hydrolytic processing of cellulose and microcrystalline cellulose, pentosan-containing agricultural waste and wood, are methods for carrying out the process at elevated and supercritical temperatures (high-temperature hydrolysis), the use of new types of solid-acid catalysts and ionic liquids.

Evaluation of Thermal Hydrolysis Efficiency of Sewage Sludge via Rheological Measurement

Thermal hydrolysis processes (THP) play an important role in sewage sludge treatment. In this study, both low-temperature (60°C–90°C) and high-temperature (120°C–170°C) thermal hydrolysis experiments were performed on the initial sludge (at a total solid of a 7.03% and 6.45% by weight). The results have shown that the release of organic matter is logarithmic with the duration during low-temperature thermal hydrolysis (LTHP). For high-temperature thermal hydrolysis (HTHP), the release of organic matter is linear with a treated temperature. Good linear relationships were obtained between the release of a soluble chemical oxygen demand (rSCOD) and soluble proteins/polysaccharides. The pH decreased with the increase of the treatment temperature. The apparent viscosity of the sludge decreased after the thermal hydrolysis, especially at a high temperature. The yield stress of the sludge disappeared, and the thixotropy increased. Moreover, the flow behavior index increased, and the consistency coefficient K decreased with the increase of the thermal hydrolyzed temperature. Meanwhile, we found a linear relationship between the rSCOD and increasing infinite viscosity. It demonstrated that the rheological measurement could be used as an indicator to evaluate the extent of organic matter solubilization in THP.

The use of enzymatic modification in recycling of meat and bone collagen-containing byproducts

The objective of this research was to study the process of extraction of valuable protein watersoluble substances from highly mineralized meat and bone raw materials during hydrolysis by proteolytic enzymes. The experiments were carried out on beef tubular and costal bones using enzymes Alcalase 2.5 L, Protamex, Protosubtilin G3x. The efficiency of protein hydrolysis was evaluated by the accumulation of nonprotein amino nitrogen in the aqueous protein extract, the amount of which was determined by formol titration. The chemical composition of raw materials and hydrolysis products was evaluated by standard physicochemical methods. The drying of hydrolyzed protein fractions was carried out on a lyophilic freeze dryer at a condenser temperature of -55 ° C. Drying of the sedimentary protein-mineral fraction was carried out by convection method at 60 about C. The general chemical composition of raw materials and protein hydrolysates is established. It was shown that fermentolysis in an aqueous medium with preliminary separation of fat and subsequent separation of fractions makes it possible to obtain low molecular weight water-soluble peptides and protein-mineral insoluble compositions, as well as fat products in the amount of 13.3–14.4 % of raw materials by weight. The yield of proteins by the content of solid products in water-soluble freeze-dried products was 6.1–7.9 %, depending on the type of enzyme and hydrolysis conditions. The bulk of the raw material's protein mass is precipitated together with mineral substances during fermentolysis. The solids content in dense sediments was 66.5–73.8 %. It is recommended to use the fermentolysis of meat and bone raw materials for pre-treatment in subsequent high-temperature hydrolysis. Protein products obtained by enzymatic modification of meat and bone raw materials are recommended for use as part of feed supplements, microbiological media and fertilizers, as well as feed for aquaculture. To accomplish that, it is necessary to study their amino acid composition and conduct biological tests. The extracted fat may also serve as a raw material for a number of fat products (margarine, spreads, soap).

Redox Behavior of Moisture in LiCl-KCl Eutectic Melts: A Cyclic Voltammetry Study

In order to develop a flow sheet for the purification procedure of a LiCl-KCl eutectic mixture with the underlying aim of avoiding Cl2 handling in an engineering-scale laboratory, the present work focuses on electrochemical investigations on vacuum dried eutectic mixtures LiCl-KCl + H2O and vacuum dried LiCl-KCl + H2O mixtures using cyclic voltammetry at 500°C. Complicated voltammetric features were observed that were attributed to the cathodic reduction of H2O to form OH−, adsorption of OH− on tungsten electrode, and cathodic reduction of OH− to form O2−. The onset of cathodic current around −0.45 V (versus AgAg as reference) was due to both cathodic reductions of H2O and HCl, the latter being formed in melt due to high-temperature hydrolysis of LiCl, although it had limited solubility as compared to that of H2O. Cyclic voltammograms also showed an anodic peak at around −0.30 V attributable to the adsorption of O2− on the tungsten electrode. A total of 19 different LiCl-KCl eutectic melts subjected to various vacuum drying conditions and moisture content were investigated in this work using cyclic voltammetry. The LiCl-KCl + H2O mixtures were prepared to simulate conditions when there is an ingress of moisture in LiCl-KCl mixtures during long storage to determine whether the mixture can be purified. A larger composition range of moisture in the LiCl-KCl eutectic mixtures was used that not only helped in the attribution of cathodic reduction peaks to reactions mentioned above but also served as references to investigate the influence of vacuum drying of moisture-containing eutectic mixtures. A two-point criterion consisting of cathodic onset LiLi potential and residual cathodic current density estimated from cyclic voltammograms in the potential region −1.5 to −2.0 V at 500°C was used to quantify the purity of the eutectic melts. Former data were compared with the theoretical equilibrium potential of −3.637 V for the LiLi couple in LiCl-KCl eutectic melt at 500°C and those obtained from cyclic voltammograms of chlorinated melt. Cathodic reduction potentials for the above reactions were then compared with literature data where they were measured against Li-Al or NiNi reference electrodes in LiCl-KCl melts. Although reduction of HCl at Pt electrode in LiCl-KCl eutectic melts was known to be reversible from literature, it was not found to be so in the present work where a tungsten working electrode was used. The LiCl-KCl eutectic mixtures vacuum dried at 300°C were found to be closer in purity to those of chlorinated melt in that the onset LiLi potential and residual cathodic current density were similar. A lower residual cathodic current density for LiCl-KCl + 2 wt% H2O vacuum dried at 300°C was also achieved with the onset LiLi potential quite close to the theoretical equilibrium potential of LiCl (−3.637 V) in the eutectic melt.

Pilot study of thermal alkaline pretreatment of waste activated sludge: Seasonal effects on anaerobic digestion and impact on dewaterability and refractory COD

Thermal alkaline pretreatment (TAP) of waste activate sludge (WAS) was carried out in pilot-scale over a year to investigate its seasonal effects on anaerobic digestion and its impact on dewaterability, sludge liquor quality and formation of soluble refractory COD (sCODref). Temperature of TAP was set at 65–70 °C and pH was increased by initial dosing of sodium hydroxide [NaOH] (50% w/w, 1–2.5 mL/L sludge) as alkali agent following 2–2.5 h reaction time. Pilot digesters were fed with primary sludge (PS) and hydrolyzed WAS (HWAS) and compared to a reference digester fed with PS and untreated WAS. Biogas yield increase due to TAP of WAS showed a sinusoidal trend throughout the year with maximum in summer (+42%), minimum in winter (+3%) and average of +20%, indicating a strong seasonal effect on TAP efficiency. Ammonium [NH4+−N], orthophosphate [PO43−−P] and sulphate [SO42−] in sludge liquor increased by 34.6%, 17.0% and 21.6% with TAP, respectively. Centrifugation tests showed no significant difference in dewaterability of both digestates with respect to total solids of sludge cake. Normalized capillary suction time of digestate increased due to TAP, indicating a lower capability for water release. Furthermore, detected sCODref after batch aerobic biodegradation tests showed an increase of 30.3% with TAP. Hence, implementation of TAP of WAS in full-scale will potentially lead to an increase of 0.8–1.1 mg/L of sCODref in effluent of six wastewater treatment plants (WWTP) in Berlin. In conclusion, TAP of WAS leads to increase in biogas production with a slighter negative impact on effluent COD quality than high-temperature thermal hydrolysis.

Определение эффективности способов конверсии пшеничных отрубей для использования их в технологии продуктов питания

В работе исследовали эффективность распада полисахаридов пшеничных отрубей кислотным и ферментативным способами. Проведен сравнительный анализ биотрансформации растительных полимеров нативных и механически активированных пшеничных отрубей мультиэнзимными комплексами: амилолитического, глюколитического и целлюлолитического действия. С целью модификации белковых компонентов пшеничных отрубей использовали композицию ферментных препаратов амилолитического и протеолитического действия. Количественный и качественный состав моно-и дисахаридов в полученных гидролизатах определяли методом ВЭЖХ, содержание аминного азота - методом Попе-Стевенса. Установлено, что при высокотемпературном химическом гидролизе полисахаридов образуется высокий уровень пентоз - 62,4 мг/г сырья; увеличилось общее содержание моно- и дисахаридов до 125,6 мг/г пшеничных отрубей. При ферментативном методе обработки как нативных так и механически обработанных пшеничных отрубей комплексом препаратов: ГлюкоЛюкс А (1 %), АмилоЛюкс АТС (0,5 %), ЦеллоЛюксА (0,5 %) определено наибольшее суммарное содержание моно- и дисахаридов - 215,2 и 216,8 мг/г отрубей соответственно, что выше в 1,7 раза в сравнении с композицией ферментов протеолитического действия. Установлено содержание аминного азота при биоконверсии комплексом ферментных препаратов Протеаза кислая и Биоферм составила 39,52 мг/г сырья.

SUBSTANTIATION OF RATIONAL PARAMETERS FOR COMPLEX PROCESSING OF SECONDARY RAW MATERIALS OF SPRAT PRODUCTION USING THE METHOD OF HIGH-TEMPERATURE HYDROLYSIS

Processing of secondary raw materials from production of canned food «Sprats in oil» is considered. Comprehensive technology is developed for producing of protein, fat, and protein-mineral food additives from the sprat waste, as smoked sprat heads, using the method of high temperature hydrolysis. Rational method of the hydrolysis is substantiated, including preliminary separation of fat in fatty raw materials and its enzymatic-thermal treatment. The optimal values of temperature and duration of hydrolysis in autoclave are determined. Balances of organic substances are calculated for the main operations. This new technology was tested for fatty (24 %) and medium fat (13 %) raw materials under the temperature of 130–160оС. The hydrolyzed organic mass was divided into fat, protein, and mineralized fractions and proteinfat emulsion. Food additives containing low molecular weight water-soluble peptides and high molecular weight insoluble proteins were extracted from the protein fraction by freeze-drying and mineral compounds were extracted from the mineral fraction by convective drying. The proteins were extracted more thoroughly, so the content of low molecular weight peptides in the freeze-dried hydrolysate of protein fraction was &gt; 80 %. The produced additives have pleasant organoleptic properties and are sanitary safe. They are tested with some seafood, with positive result. The developed technology for processing of smoked waste is economically valuable and allows to solve the problem of pollution in the fish smoking industry.

Effect of high-temperature thermal hydrolysis on rheological properties and dewaterability of sludge

ABSTRACT The disposal processes like dewatering and anaerobic digestion (AD) are commonly utilized to reduce the volume of sludge and recover energy. Thermal hydrolysis process is widely used as a pretreatment for sludge AD, which can change rheological properties and dehydration of sludge irreversibly. The experiment was designed to evaluate the effect of high-temperature thermal hydrolysis (120, 130, 145, 160 and 170°C) for 60 min on sludge rheological properties, as well as its dewaterability. Rheological tests were performed at (20 ± 0.1)°C with a HAAKE Viscotester 550 Rotary Viscometer. Both raw and thermal hydrolysis sludge has a considerable reduction on apparent viscosity and yield stress, but a somewhat increase in thixotropy. With the increase of temperature, the sludge flow behaviour index n increases linearly, while the consistency coefficient k follows the law of linear decline, showing that thermal hydrolysis can weaken the non-Newtonian fluid properties and then improve sludge fluidity. The dewaterability increases linearly with the temperature. Besides, the dewaterability of high-temperature thermal hydrolysis processes sludge was always significantly better than raw sludge as its mud cake has a much larger solid content. Notably, the increase in flow performance index n and the decrease of thixotropy kinetic coefficient K caused by thermal hydrolysis are all linear with the enhancement of dewaterability, which demonstrates that rheological indicators can be a new tool to evaluate the dewaterability of sludge.

Исследование процесса модификации мясокостного сырья крупного рогатого скота методом высокотемпературного гидролиза

Исследование процесса модификации мясокостного сырья крупного рогатого скота методом высокотемпературного гидролиза

Silica Glass for High-Q Mechanical Resonators

This paper addresses issues related to the choice of materials for the fabrication of high-Q mechanical resonators. It has been shown that the best material combining a low level of thermoelastic losses and small bulk internal friction is silica glass. Given its excellent dissipative characteristics and relatively low cost, silica glass prepared via high-temperature hydrolysis of silicon tetrachloride in an oxygen–hydrogen flame is the most promising material for such resonators.

Fast protein analysis enabled by high-temperature hydrolysis.

While the bottom-up protein analysis serves as a mainstream method for biological studies, its efficiency is limited by the time-consuming process for enzymatic digestion or hydrolysis as well as the post-digestion treatment prior to mass spectrometry analysis. In this work, we developed an enzyme-free microreaction system for fast and selective hydrolysis of proteins, and a direct analysis of the protein digests was achieved by nanoESI (electrospray ionization) mass spectrometry. Using the microreactor, proteins in aqueous solution could be selectively hydrolyzed at the aspartyl sites within 2 min at high temperatures (∼150 °C). Being free of salts, the protein digest solution could be directly analyzed using a mass spectrometer with nanoESI without further purification or post-digestion treatment. This method has been validated for the analysis of a variety of proteins with molecular weights ranging from 8.5 to 67 kDa. With introduction of a reducing agent into the protein solutions, fast cleavage of disulfide bonds was also achieved along with high-temperature hydrolysis, allowing for fast analysis of large proteins such as bovine serum albumin. The high-temperature microreaction system was also used with a miniature mass spectrometer for the determination of highly specific peptides from Mycobacterium tuberculosis antigens, showing its potential for point-of-care analysis of protein biomarkers.

Hydrolysis as a basis for processing vegetable waste into bioplastics

The greening of processing waste from logging and woodworking industries involves measures to prevent the negative impact of production processes on the natural environment and is enabled by the development of resource-saving techniques that minimize harmful emissions to the environment. These production operations are based on hydrolytic cleavage of glycoside bonds of vegetable biomass polysaccharides with the formation of monosaccharides as the main reaction products. Despite the wide range of available methods of processing wood into promising materials (heat treatment, pyrolysis, hydrolysis, etc.), one of the most effective methods is to produce sugars by weak acids hydrolysis. In this regard, the paper describes the technology of high-temperature hydrolysis of pine sawdust with sulfurous acid in order to detect reducing substances (RS) in the hydrolysis residue. The paper considers the effect of sulfurous acid, temperature, and treatment time on the yield of RS.

Preparation and Properties of Foaming Agent for Air Foam Flooding

In order to meet the requirements of air foam flooding in Dagang Gangdong Oilfield, two kinds of foaming agents, GFPA-1 and GFPA-2, were prepared by sulfonation, neutralization and high-temperature hydrolysis of α-olefins with different carbon chain lengths in the laboratory. The test results of foaming agents for its properties showed that when the concentration of foaming agent was over 0.5%, the initial foaming volumes of the two foaming agent systems were more than 500mL, and the foam half-life of GFPA-2 was about 3.5 hours, obviously longer than that of GFPA-1. Therefore, GFPA-2 was selected as the foaming agent for air foam flooding. The experimental results of static adsorption, plugging and core displacement performance of GFPA-2 foaming agent showed that the initial foaming volume of GFPA-2 foaming agent could still maintain 500mL after 48 hours of adsorption at a concentration of 0.5%, and when the ratio of gas to liquid was 1: 1, the resistance factor was more than 50. When a 0.4% foaming agent was injected with 0.35 PV slug, the displacement efficiency of air foaming flooding was 17.4% higher than that of water flooding.

Improvement of Biodegradability and Biocompatibility of Electrospun Scaffolds of Poly(butylene terephthalate) by Incorporation of Sebacate Units

Incorporation of aliphatic units to poly(butylene terephthalate) (PBT) gives rise to biodegradable copolymers with tunable properties (e.g., degradability), depending on the selected comonomer and the specific composition. Specifically, a low molecular weight poly(butylene sebacate-co-terephthalate) (PBSeT) with a high ratio of aliphatic sebacate units (i.e., 70 mol-% with respect to the total dicarboxylate content) has been employed in this work to get new electrospun biodegradable scaffolds. Appropriate electrospinning conditions have been found despite the limited copolymer molecular weight. In addition, PBSeT has been employed to improve biocompatibility and biodegradability of scaffolds based on the PBT homopolymer. Scaffolds with different properties have been prepared following two strategies: Electrospinning of single solutions of PBT and PBSeT mixtures and co-electrospinning of independent PBT and PBSeT solutions. Characterization involved spectroscopic (FTIR, NMR), calorimetric (DSC, TGA) and surface hydrophobicity analyses. Hydrolytic and enzymatic degradation studies demonstrated the success of the approach due to the susceptibility of the PBSeT component towards the enzymatic attack with lipases from Pseudomonas cepacia and even towards high temperature hydrolysis.

Processing Induced Degradation Routes of Prochloraz in Rapeseed Oil.

Analyzing the fate of substances in complex matrices, such as processed food, is a major challenge in modern analytical chemistry. However, current regulatory procedures for pesticides only include high temperature hydrolysis of the active substance in water (OECD 507) to simulate food processing. This study shows that heating radiolabeled [imidazolyl-2-14C]prochloraz in virgin rapeseed oil at temperatures up to 240 °C leads to an extensive degradation of the active substance. In total, 11 degradation products were identified. Several of these products were formed by reactions of the active substance with ingredients from the oil. 2-[(1-H-Imidazole-1-carbonyl)(propyl)amino]ethyl oleate (icpame-oleate), a reaction product of an oleic acid moiety and the prochloraz backbone, was identified for the first time. The quantification of prochloraz, icpame-oleate, imidazole, and 2,4,6-trichlorophenol demonstrated the dependency of the degradation process on temperature, heating duration, and type of oil. The obtained results in this study show the enormous impact of high temperature food processing on the fate of pesticides. The necessity to consider matrix related reactions in pesticide regulation is emphasized, and the suitability of the OECD 507 guideline is questioned. Concerning possible toxicological risks of novel degradation products, future studies will have to assess potential hazards or opportunities of food processing, ultimately yielding in safer food.