Alcohols In Yields Research Articles

ДОСЛІДЖЕННЯ УМОВ ОДЕРЖАННЯ АЛКОГОЛЬНИХ НАПОЇВ З ЯБЛУК

The results of research on the fermentation process of apple juice and its concentrate are described. For this, two races of yeast of the types Saccharomyces bayanus (France) were selected and wild yeast was taken for comparison. The influence of temperature (10–30 0C) and duration of fermentation (12–40 days) on alcohol yield, content of total extract and sugar is shown. The quality characteristics of fruit wines characterized by aroma, strength, extract and sugar content has been established. The suitability of ciders for the production of calvados by distillation and aging of the obtained drinks has been studied. The taste and aroma of the obtained drinks were evaluated, namely: the strength, extract content and aroma, which affect the quality of the obtained products, were determined. An organoleptic evaluation of the obtained products and French Calvados was made.

Research of topinambur water-heat and enzymatic processing modes for ethyl alcohol producing

Currently, the search for alternative sources of raw materials for the production of ethyl alcohol and related food and feed products is becoming increasingly relevant. One of the promising sources is jerusalem artichoke (topinambur). This crop has a high yield, is unpretentious, rich in polysaccharides. One of the problems in the production of ethyl alcohol from jerusalem artichoke tubers is the effective conversion of raw material polysaccharides into sugars digestible by alcohol yeast. Considering the seasonality of this crop and the difficulties in storage, it is necessary to integrate the technology of its processing as much as possible into the conditions of existing plants for processing grain raw materials into alcohol. The paper considers the most common options for water-thermal and enzymatic treatment of grain mashes in the production of ethyl alcohol in relation to Jerusalem artichoke. At the same time, it was shown that the highest results, with an alcohol yield of up to 98 liters per 1 ton of Jerusalem artichoke, are achieved when the mass is processed according to a mechanical-enzymatic scheme at a temperature of 90-95 °C using inulase enzyme for saccharification.

Valorization of the Wheat Bran C5 Fraction Using Ru/ZrO2-MCM48 Catalysts

Monometallic Ru/MCM48 and Zr/MCM48 and bimetallic Ru/Zr-MCM48 and Zr/Ru-MCM48 catalysts have been synthesized and tested in the hydrogenation of wheat bran hydrolysates. Catalysts have been characterized by XRD, SAXS, TPR, TPD-NH3, TEM, and N2 adsorption/desorption at 77 K. The hemicellulose fraction has been extracted, hydrolyzed, and purified before the hydrogenation reaction. The purification step mainly consists of the extraction of the sugars in an organic phase and a back-extraction in an acid-aqueous solution. Ru/Zr-MCM48 catalyst exhibited the highest conversions of sugars in the hydrogenation of the purified wheat bran hydrolysate (PWBH), practically unchanged after 5 reaction cycles. Sugar alcohol yields were 73.2% in pentitols and 65.9% in sorbitol. The incorporation of the tetragonal ZrO2 to the MCM48 support has led to a more active and stable catalyst for the hydrogenation of PWBH. Results have shown that this incorporation must be done before the deposition of the Ru(0) phase.

The formation of higher alcohols in rice wine fermentation using different rice cultivars.

Higher alcohols are closely related to the flavor and safety of rice wine. The formation of n-propanol, isobutanol, isoamyl alcohol, and phenylethanol during rice wine fermentations was for the first time investigated in this study among 10 rice cultivars from two main production regions. Rice wine made from Yashui rice, the long-grain non-glutinous rice from Guizhou, produced the highest yields of higher alcohols (487.45 mg/L), and rice wine made from five glutinous rice cultivars produced the lowest yields of higher alcohols (327.45-344.16 mg/L). An extremely strong correlation was found between the starch in rice and higher alcohols in rice wine. Further analysis first showed that the former fermentation period was key for the nutrient consumption and higher alcohol formation, with more than 55% of glucose being consumed and more than 75% of higher alcohols being synthesized in 48 h. Correlation analysis confirmed the strong correlation between nutrient consumption and higher alcohol formation including valine-isobutanol (coefficient higher than 0.8 in seven rice cultivars and higher than 0.6 in three rice cultivars), glucose-isoamyl alcohol (coefficient higher than 0.8 in five rice cultivars and higher than 0.6 in the other five rice cultivars), and glucose-phenylethanol (coefficient higher than 0.8). The correlation of threonine-n-propanol, leucine-isoamyl alcohol, phenylalanine-phenylethanol, glucose-n-propanol, and glucose-isobutanol varied among the rice wines made from 10 rice cultivars. RT-qPCR analysis on five target genes verified the variation caused by different rice cultivars. this study for the first time reported the special formation pattern of higher alcohols during rice wine fermentation, emphasizing the early contribution of glucose metabolism on the formation of isobutanol. This study highlighted the significance of rice selection for making rice wine with good quality and provided theoretical references for the control of higher alcohols, especially in the former period of rice wine fermentation.

Sustainable Aviation Fuel from Syngas through Higher Alcohols

AbstractThe current review critically summarizes recent developments in transformations of syngas to higher alcohols. Although higher alcohols have found applications as fuel additives, detergents and plastics for a long while, transformation of alcohols to jet fuel has attained recent interest due to an urgent need to develop jet fuels from sustainable sources. Fermentation of lignocellulosic‐based sugars to ethanol as a technology does not compete with the food chain supply being thus a potentially acceptable route if economically viable. An alternative method is to gasify biomass to produce syngas, which can further be transformed to higher alcohols through several pathways. Jet fuel range alkanes are obtained from alcohols via oligomerisation, dehydration and hydrogenation. The highest space time yields of higher alcohols of 0.61 g/(gcath) is obtained over a bimetallic copper‐iron catalyst supported on a hierarchical zeolite at 300 °C and 5 MPa. Furthermore, copper‐cobalt and cobalt‐manganese compositions are promising for the direct synthesis of higher alcohols from syngas, where one of the challenges is to suppress formation of alkanes and CO2 and increase selectivity to higher alcohols. From the mechanistic point of view, it has been proposed to use dual‐site catalysts, where one site promotes hydrogenation, while the other site is required for the chain growth. In addition to selection of the optimum reaction conditions and catalyst properties, kinetic modelling, thermodynamics and scale up issues are discussed.

Approaches on Improving Electroreduction of Carbon Monoxide to Acetate in Flow Electrolyzer

Acetic acid (CH3COOH) is an important industrial chemical that is widely used in the generation of various products including medicals, food, solvent, synthetic fibers and fabrics. Although most acetic acid production today relies on the carbonylation process of methanol1, electrochemical synthesis method is a promising direction owing to its uniqueness in ambient conditions, utilization of renewable energy, and compatibility with bioengineering2. Cupper has the capability to electrochemically reduce CO2 to various C2 products but with low selectivity. The critical steps for acetate molecule generation from CO2/CO are the CO-dimerization and the nucleophilic attack of hydroxide ion on a ketene intermediate3, in which acetate production could be enhanced by electroreducing CO in alkaline electrolyte as compared to CO2 electroreduction in pH neutral solution. Meanwhile, the use of flow electrolyzer further improved the gas transport process by employing gas diffusion electrode, boosting the current and yield rate of products to industrial level. However, electrochemical reduction of CO to acetate on Cu-based electrocatalysts still suffers from low faradaic efficiency (<50%).4 In this talk, we will present our recent work on CO electroreduction to acetate by commercial Cu catalyst in flow electrolyzer. Parameters in terms of electrolyte molarity, catalyst loading, catalyst deposition method, and ionomer were manipulated to maximize the acetate production. Acetate was favored in high pH electrolyte by facilitating the nucleophilic attack of hydroxide ion process and suppressing competing proton transfer process towards ethylene and ethanol. Catalyst loading on gas diffusion electrode had great influence on the products selectivity, where low catalyst loading leans to ethylene generation, intermediate catalyst loading is selective to produce acetate, and high catalyst loading improves alcohol yield. A record 68% faradaic efficiency of acetate from CO with partial current density of 102 mA/cm2 was reached. Reference A. Dimian and A. Kiss, Chem. Eng. Res. Des., 159 (2020).S. Guo, T. Asset, and P. Atanassov, ACS Catal., 5172–5188 (2021) https://pubs.acs.org/doi/abs/10.1021/acscatal.0c04862.M. Jouny et al., Nat. Chem., 11, 846–851 (2019) https://doi.org/10.1038/s41557-019-0312-z.W. Luc et al., Nat. Catal., 2, 423–430 (2019) https://doi.org/10.1038/s41929-019-0269-8. Figure 1

N-rich doping strategy for constructing Ni@NC catalysts to boost aqueous ethanol coupling towards higher alcohols by inhibiting C1 byproducts

Aqueous coupling of biomass fermentation bio-ethanol offers a promising biorefinery pathway for manufacturing higher alcohols, but it still suffers from the poor utilization efficiency due to the excessive formation of undesired C1 byproducts (CH4, CO and CO2). Herein, N-rich Ni@NC catalysts were synthesized via a facile one-step carbonization of organic–inorganic co-assembly containing polyacrylamide and nickel acetate. Interestingly, the optimized Ni@NC catalyst exhibited excellent performance in aqueous ethanol coupling, giving 74.8 % of ethanol conversion, 49.3 % of C4+ higher alcohol yield and only 1.6 % of C1 gas byproduct selectivity after 12 h reaction at 230 °C. The experimental results and DFT calculations revealed that the regulation of N-rich doping weakened the interaction of Ni with intermediated CH3CHO for inhibiting its deep decomposition into C1 gas byproducts, thereby facilitating the coupling reaction to produce more higher alcohols. Moreover, a feasibility to scale-up the aqueous ethanol coupling was further validated through a 100-fold magnification experiment at ranges of 50–5000 mL, and the fuel properties of higher alcohols as diesel blending were also evaluated. This work opens new avenues for efficient mass-production of higher alcohols via aqueous ethanol coupling.

Nitrogen fertilization of rice plants before flowering affects sake fermentation and quality

AbstractBackground and ObjectiveNitrogen fertilizer applied as top‐dressing to rice plants before flowering affects the yield and quality of rice grains. However, little is known about the effects of varying dosages of nitrogen at this stage on the brewing properties of sake using the rice grains. To explore this topic, we cultivated the sake rice cultivar “Koshitanrei” with low and high levels of nitrogen (equivalent to 10 kg and 30 kg N per hectare, respectively) applied 1 week before flowering and then conducted a small‐scale sake brewing test using the harvested rice.FindingsSake made from rice from the low‐N treatment was fermented more efficiently. This yielded a higher volume of sake with a higher alcohol concentration and decreased amino acid concentrations.ConclusionsThe use of rice from the low‐N treatment enhanced alcohol fermentation, resulting in increased alcohol yield and decreased concentrations of amino acids and related compounds.Significance and NoveltyThe amount of nitrogen applied to rice plants before flowering affects the fermentation properties of rice grains in sake brewing, and this can alter the quality and sensory properties of sake even though the nitrogen content of rice grains is unaffected.

Efficient Catalytic Upgrading of Ethanol to Higher Alcohols via Inhibiting C–C Cleavage and Promoting C–C Coupling over Biomass-Derived NiZn@NC Catalysts

The conversion of renewable bioethanol into high-energy-density higher alcohols has become essential for meeting the increasing global demand to achieve carbon neutrality. In this study, Zn- and nitrogen-codoped Ni-based lignin-derived carbon catalysts (NiZn@NC) were prepared by solvent volatile self-assembly and in situ reductive carbonization using pulp and paper waste stream alkali lignin as the carbon source. Lignin amphipathic derivatives with −COOH and −NH2 groups would coordinate with metal ions to form a stable lignin–metal framework; thus, the lignin-derived carbon layer disperses the NiZn bimetallic catalyst and prevents from corroding. At an amination reagent/lignin mass ratio of 1:2, an ethanol conversion of 75.2% and a high alcohol yield of 41.7% were achieved over the Ni20Zn1@NC catalyst. Experimental results and density functional theory calculations showed that Zn doping improved the electronic environment and defect structures of metallic Ni and carbon carrier, which effectively inhibited C–C cleavage and suppressed the byproduct formation, such as methane. Thereby, the synergetic effect between Ni and Zn facilitated the efficient conversion of aqueous ethanol into higher alcohols by the Guerbet reaction. This work provides a strategy of in situ pyrolytic doping and stabilizing of renewable biomass macromolecules as the frameworks for the construction of highly active and cost-efficient catalysts for ethanol upgrading.

Production of distilled spirits using grain sorghum through liquid fermentation

The objectives of this research were to investigate the fermentation performance of US sorghum varieties for the production of distilled spirits as well as their associated coproducts and to study the formation of volatile compounds that are related to the flavor quality of the spirits. Three US sorghum varieties (red, white, and waxy sorghums) and four yeast strains (DADY, Ethanol Red, GR-2, and 71B) were used for distilled spirit production. Both sorghum variety and type of yeast strains had effects on alcohol concentration and alcohol yield. The alcohol concentration varied from 10.26 to 11.34% (v/v) while alcohol yield varied from 80.93 to 90.33%. Using Ethanol Red yeast achieved consistently the highest average alcohol concentration (11.10%, v/v) and yield (87.33%) regardless of variation in sorghum variety. Waxy sorghum demonstrated significantly higher average alcohol concentration (11.20%, v/v) and yield (89.65%) than white sorghum (10.74% for concentration and 84.7% for yield) and red sorghum (10.28% for concentration and 82.27% for yield). Alcohol fermentation also produces other metabolites as byproducts. Glycerol and lactic acid are the two major byproducts found from sorghum spirit fermentation. DADY produced the highest level of glycerol (∼1.4–1.5%, v/v) during fermentation, while GR-2 produced the lowest level of glycerol (0.9–1.1%, v/v). For all conditions, the lactic acid level was less than 1.2% (v/v). Eight volatile compounds were identified in sorghum spirits which mainly relate to fruity, sour, sweet, floral, buttery, and creamy flavors of the spirits. • Distilled spirits were produced using three sorghum varieties and four yeast strains. • Both sorghum variety and yeast strains had effect on alcohol concentration and yield. • Waxy sorghum demonstrated significantly higher alcohol concentration and yield. • Ethanol Red yeast achieved consistently the highest average alcohol concentration. • Eight major volatile compounds were identified in sorghum spirits.

Preliminary Studies on the In Vitro Interactions Between the Secondary Metabolites Produced by Esca-Associated Fungi and Enological Saccharomyces cerevisiae Strains.

Esca-affected vines alter the carbohydrate metabolism, xylem transport of water and photosynthesis and show regular grapes (but berries do not reach maturity), and phenolic compounds are reduced in concentration, oxidate and polymerizate. Pullulan and a mixture of scytalone and isosclerone (9:1; w/w), secondary metabolites produced in vitro and in planta by Phaeoacremonium minimum (syn. P. aleophilum) and Phaeomoniella chlamydospora, were assayed against the strains Byosal HS1 and IOC 18-2007 in microvinifications with synthetic grape must. The presence of pullulan and pentaketides mix affects the growth and metabolism of the tested Saccharomyces cerevisiae strains. Assays at 100 and 1000 µg mL−1 inhibited the growth of both strains, while no effects were recorded when evaluated at 1 and 5 µg mL−1. In comparison with the controls, pullulan and the scytalone/isosclerone mixture at 10 µg mL−1 had a growth reduction, a lower alcohol yield, reduced the concentration of tartaric acid and malic acid; and slowed down the production of lactic acid, acetic acid and total polyphenol content of the tested S. cerevisiae strains. These metabolites could be applied as an alternative to the sulfite addition in the early stages of vinification to support the action of selected Saccharomyces. Appealing is the subtractive action of pullulan against tartaric acid. Further data are needed to confirm and validate the enological performance in freshly pressed grape juice.

Chemical and volatile composition of Pálinka produced using different commercial yeast strains of Saccharomyces cerevisiae

Pálinka is Hungarian traditional alcoholic drink, and its quality is strongly depending on applied yeast strain. Unfortunately, all commercial yeast strains used the production of pálinka are selected for oenological purpose, and thus the efficacy and aroma releasing capacity are vary depending on the type and quality of fruit used. In this study, the fermentation efficacy of nine commercial yeast strains of Saccharomyces cerevisiae was focused. All strains were able to do alcoholic fermentation of apple juice quite efficiently, and the simple sugars (fructose, glucose and sucrose) were almost exhausted at the end of fermentation. Meanwhile, the alcohol production capacity and yield were no significant differences (around 9.17 v/v %–9.43 v/v %), whereas the ability of sugar consumption of strains Uvaferm Danstil A and Fermicru AR2 was stronger than others. The differences in the concentration and composition of volatile compounds were recorded. The highest levels of total volatile compounds were observed in samples fermented with Uvaferm Danstil A, Fermiblanc Arom, Vin-O-Ferm Roses, and Fermicru AR2. Meanwhile total volatile compounds, 2-methyl-1-propanol, 3-methyl-1-butanol, total higher alcohols, ethyl acetate, and total esters were considered as key parameters for describing the profile of fermented apple juices, whereas total fusel alcohols, 2-methyl-1-propanol, 2-methyl-1-butanol, 3-methyl-1-butanol, and total volatile compounds were characteristic indicators of samples fermented with Uvaferm Danstil A. This work provides very good information of commercial yeast strains for industrial pálinka production.

Optimization of Mashing Parameters Used during the Conversion of Irish Wheat Grain to Spirit Alcohol

The Irish distilling industry is rapidly expanding, diversifying its growth with an increased interest in using different grains in whiskey production. To effectively use Irish-grown wheat in distillation, the identification of cultivars that are suited to the Irish climate and provide high alcohol yields, via a quick screening test for grain alcohol yield that is consistent with Irish industry standards, is required. The current study used response surface methodology (RSM) to optimize mashing parameters, enzyme dosage rate (α-amylase and amyloglucosidase), time, temperature, and malt inclusion rate, using a hard wheat (Triticum aestivum cv. Costello). By optimizing all factors, a maximum alcohol yield (AY) of 471 LA/tonne dry weight basis was achieved, equating to previous research. The enzyme, α-amylase plays a critical part in the process, of converting starch to sugars, and 48 U/g α-amylase was used to reach maximum alcohol yield. Furthermore, an optimal protocol was evaluated on soft wheat cultivars, producing alcohol yields in the range of 483–496 LA/tonne, suggesting the applicability of this product for use across multiple varieties and grain endosperm types. In summary, an optimal alcohol yield methodology was created, with increased AY across four distinct varieties, demonstrating the possibility for Irish cultivated wheat to be used in Irish distilleries.

Electronic Metal‐Support Interaction Strengthened Pt/CoAl‐LDHs Catalyst for Selective Cinnamaldehyde Hydrogenation

AbstractCinnamaldehyde (CAL) is a typical sustainable biomass molecule which is classified as α, β‐unsaturated aldehydes. Selective hydrogenation of CAL to produce high‐value and fine chemical cinnamylalcohol (COL) is an attractive catalytic transformation process. However, the hydrogenation of C=O bond in CAL is more unfavorable than C=C bond in thermodynamics and kinetics, leading to great challenge on achieving high yield of unsaturated alcohol. In this work, a Pt/CoAl‐LDHs catalyst was prepared for hydrogenation of CAL to COL, showing outstanding intrinsic activity (TOF as high as 4.93 s−1) and finally achieving 93.6 % selectivity at 95.4 % conversion. In contrast, the yields of COL over Pt/Co(OH)2 and Pt/Al(OH)3 were only 73 % and 34 % respectively. Characterizations including Raman, O‐XAFS, XPS revealed that the Co2+−O2−−Al3+ structure in CoAl‐LDHs contributed to strengthened metal‐support interactions, and resulted in electron‐rich and geometric decoration Ptδ− sites. The electron‐rich Ptδ− provided preferable H2 activation capability, and also exposed abundant unsaturated sites which optimized the adsorption mode of cinnamaldehyde favorable for C=O hydrogenation. However, in Pt/Co(OH)2 and Pt/Al(OH)3 catalysts, the Pt0 without electron‐rich and unsaturated property cannot improve the H2 activation capability as well as electronic repellency to C=C bond. In addition, a possible catalytic mechanism was proposed to illustrate the role of Ptδ−−Co2+−O2−−Al3+ interfacial structure on enhancing activity and selectivity.

Preparation of an Ionic Liquid Based on Polystyrene Microspheres to Catalyze the Conversion of Furfuryl Alcohol to Ethyl Levulinate

AbstractExhaustion of petroleum resources is seriously accelerating, hence, it is crucial to find renewable energies and change the global energy consumption structure. Biomass energy is the only carbon ‐ containing energy currently available and is irreplaceable in the preparation of fuels and chemicals. This study focuses on the transformation of furfuryl alcohol to ethyl levulinic acid ester using our prepared catalyst consisting of ionic liquid on polystyrene microspheres. The catalyst was characterized by IR, TG, XRD, BET and XPS techniques. In the presence of our catalyst, the conversion of furfuryl alcohol and ethyl levulinic acid yield was 98.54 % and 92.41 %, respectively. Repeated experiments showed that the acidic sites on the catalyst were occupied, slightly decreasing catalytic performance. However, after soaking and washing in concentrated sulfuric acid the catalytic activity was recovered, indicating immobilization on catalyst's surface and its stability during the reaction.

Promising Recyclable Ionic Liquid-Soluble Catalytic System for Reductive Hydroformylation

We report here the reductive hydroformylation of methyl 10-undecenoate (issued from castor oil) in a biphasic liquid/liquid system. The rhodium/amine catalytic system is immobilized in an ionic liquid phase, whereas the olefin and the products are in a nonpolar layer. The effects of various reaction parameters (nature and concentration of amines, nature of ionic liquids, temperature and syngas pressure or composition) were studied to increase the production of primary alcohols. Under optimized conditions, potassium N,N-dimethyltaurinate salt associated with rhodium, immobilized in 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide, allowed us to attain 93% of alcohol yield. With only 2 equiv of amine with respect to rhodium, the catalytic system can be efficiently immobilized in the ionic liquid and recycled due to the ionic nature of the involved catalytic species.

Highly Efficient Transfer Hydrogenation of Biomass-Derived Furfural to Furfuryl Alcohol over Mesoporous Zr-Containing Hybrids with 5-Sulfosalicylic Acid as a Ligand.

The catalytic transfer hydrogenation of biomass-derived furfural to furfuryl alcohol under mild conditions is an attractive topic in biorefinery. Herein, mesoporous Zr-containing hybrids (Zr-hybrids) with a high surface area (281.9–291.3 m2/g) and large pore volume (0.49–0.74 cm3/g) were prepared using the biomass-derived 5-sulfosalicylic acid as a ligand, and they were proven to be highly efficient for the Meerwein–Ponndorf–Verley reduction of furfural to furfuryl alcohol at 110 °C, with the highest furfuryl alcohol yield reaching up to 97.8%. Characterizations demonstrated that sulfonic and carboxyl groups in 5-sulfosalicylic acid molecules were coordinated with zirconium ions, making zirconium ions fully dispersed, thus leading to the formation of very fine zirconia particles with the diameter of <2 nm in mesoporous Zr-hybrids. The interaction between the 5-sulfosalicylic acid ligands and zirconium ions endowed mesoporous Zr-hybrids with relatively higher acid strength but lower base strength, which was beneficial for the selective reduction of furfural to furfuryl alcohol. A recycling study was performed over a certain mesoporous Zr-hybrid, namely meso-Zr-SA15, demonstrating that the yield and selectivity of furfuryl alcohol remained almost unchanged during the five consecutive reaction cycles. This study provides an optional method to prepare hybrid catalysts for biomass refining by using biomass-derived feedstock.

Facile synthesis of Ni/Fe3O4 derived from layered double hydroxides with high performance in the selective hydrogenation of benzaldehyde and furfural

Efficient upgrading of biomass-derived platform chemicals plays a crucial role in the sustainable synthesis of fine chemicals. Herein, the noble-metal free and robust Ni/Fe3O4 catalysts originated from NiFe-layered double hydroxides (LDHs) was efficient for the selective upgrading of benzaldehyde (BzH) and furfural (Fur), accordingly, the highest yield of fine chemical benzyl alcohol (99.0%, BAL) and biofuel 2-methylfuran (78.4%, 2-MF) were obtained under mild conditions over the Ni/Fe ratio of 1, respectively. These performance is far superior to most of preciously reported candidates and their counterpartners. Systematic characterizations further revealed that Ni2+/Fe3+ ratio was closely related to the dispersion and the surface acidity of catalysts, which played crucial roles in achieving excellent catalytic performance. Besides, the solvent effect, reaction parameters and reusability of catalysts in the hydrogenation process of benzaldehyde were then studied as example. Finally, the reaction pathways of benzaldehyde and furfural hydrogenation were rationally proposed. This work provides a promising way to upgrade biomass-derived chemicals.

Intensification of ethyl alcohol technology due to multienzyme composition

The effect of the complex enzyme preparation Bruzaym BGX on the viscosity of rye kneading was studied. The dynamics of glucose accumulation in the wort is shown, as well as the possibility of reducing the dosage of glucoamylase when using a multi-enzyme complex at the stage of water-heat treatment. The effect of the enzyme complex on the fermentation kinetics of rye wort was studied. It was found that the use of a multienzyme complex at the stage of water-heat treatment allows one to increase the glucose content in the wort by 34.7 %, compared with the control. This increases the yield of alcohol by 1.4 decalitres/t of conditional starch, reduces the duration of fermentation to 50 – 52 hours and reduces the total content of impurities in the mature brew by 10%.

Selective hydrogenation of α,β-unsaturated aldehydes over Pt supported on cerium–zirconium mixed oxide of different composition

Cerium–zirconium mixed oxides with different Ce/Zr ratio were prepared and used as supports for Pt-containing catalysts. The study of the catalysts in the cinnamaldehyde hydrogenation reaction has shown that cinnamaldehyde conversion and cinnamyl alcohol selectivity strongly depend on the CeO2 content in the support. The highest cinnamyl alcohol yield of 81% was obtained in 105 min at room temperature and atmospheric pressure over the 1%Pt/CeO2–ZrO2 catalyst with Ce : Zr atomic ratio equal to 4 : 1.