Enzyme Preparation Research Articles

Kinetic and thermodynamic investigation of Rhodanese synthesized by enhanced Klebsiella oxytoca JCM 1665 strain: a comparative between the free and immobilized enzyme entrapped in alginate beads

Klebsiella oxytoca JCM 1665 was subjected to extracellular rhodanese production using a submerged fermentation technique. The organism was further engineered for higher cyanide tolerance and rhodanese yield using ethylmethanesulfonate as a mutagen. Mutagenesis resulted in an improved mutant with high cyanide tolerance (100 mM) and rhodanese yield (26.7 ± 0.67 U/mL). This yield was 4.34-fold higher than the wild strain (6.15 ± 0.65 U/mL). At temperatures ranging from 30 to 80 °C, the first-order thermal denaturation constant (Kd ) for free enzyme increases from 0.00818 to 0.0333 min−1 while the immobilized enzyme increases from 0.003 to 0.0204 min−1. The equivalent half-life reduces from 99 to 21 minutes and 231 to 35 minutes, respectively. Residual activity tests were used to assess the thermodynamic parameters for both enzyme preparations. For the free enzyme, the parameters obtained were enthalpy (29.40 to 29.06 kJ.mol−1), entropy (−194.24 to −197.50 J.mol−1K−1) and Gibbs free energy (90.20 to 98.80 kJ.mol-1). In addition, for immobilized rhodanese, we obtained enthalpy (40.40 to 40.07 kJ.mol−1), entropy (−164.21 to − 165.20 J.mol−1K−1) and Gibbs free energy (91.80 to 98.40 kJ.mol−1. Regarding its operational stability, the enzyme was able to maintain 63% of its activity after being used for five cycles. Immobilized K. oxytoca rhodanese showed a marked resistance to heat inactivation compared to free enzyme forms; making it of utmost significance in many biotechnological applications.

Transformation of agricultural wastes into functional oligosaccharides using enzymes and emerging technologies.

Pectin-oligosaccharides (POS) serve diverse purposes as a food ingredient, antimicrobial and biostimulant in plants, and their functionality is linked to the degree of esterification. Grape and broccoli wastes emerge as environmentally friendly alternatives to obtaining pectin, serving as a sustainable source to producing POS. For example, microwaves have proven to be an effective and sustainable method to extract polysaccharides from plant matrices. This work aims to use grape and broccoli wastes as alternative sources for obtaining pectin by microwave-assisted extraction and biotransformation into POS, which possess biological properties. The extraction conditions were identified at a power of 400 W, 300 s for the extraction of pectin from grape pomace and broccoli waste. Biotransformation of pectins into POS, using commercial enzyme preparations (Viscozyme L and Pectinase). Characterisation was carried out by Fourier-transform infrared spectroscopy, thermogravimetric analysis, and scanning electron microscopy. Physicochemical analysis indicated grape pomace and broccoli waste pectins had galacturonic acid content of 63.81 ± 1.67 and 40.83 ± 2.85 mg 100 mg-1, low degree of esterification of 34.89% and 16.22%, respectively. Biotransformation of pectins into POS resulted in a 20% hydrolysis rate. The main enzymatic activity was polygalacturonase for the degradation of the main structure of the pectin. Production of POS from agro-industrial wastes by emerging technologies, such as the combined use of microwave-assisted extraction and enzymatic processes, represents an alternative method for the generation of bioactive compounds with distinctive properties suitable for different applications of interest.

Development of technology for obtaining juice from persimmon fruit (Diospyros kaki L.)

Organizing proper and environmentally friendly nutrition is one of the most pressing problems. Widespread persimmon fruits are of great technological importance as raw materials for the production of concentrated juice, used as a natural sweetener. The object of this study is the processes of obtaining juices from persimmon fruits. Quality indicators were studied in juices prepared by preliminary heat treatment and the use of an enzyme preparation. The juice yield from the Khachia variety was 93.9 %, and from the Hiakume variety – 93.8 %. To prepare concentrated juice, persimmon juice was used, prepared by preliminary heat treatment, and using 0.1–0.2 % enzyme preparation. A scheme for preparing concentrated juice has been developed, which is recommended for use as an environmentally friendly sweetener in food production. The concentrate contained 7.25 µg/100 g of iodine. The prepared concentrate is rich in nutritional components necessary for human life, as well as sugars, phenolic compounds with antioxidant and antimicrobial properties, as well as vitamin C. Nutritional components perform a wide range of functions in the optimal functioning of the immune system and play an important role in metabolic processes. The use of persimmon concentrate in the preparation of various food products increases the bioavailability of many minerals. Therefore, to ensure the nutritional value of the finished product and increase long-term quality storage, it is recommended to use concentrated persimmon juice as a sugar substitute

Розповсюдженість, властивості та практичне значення α-галактозидази

The achievements of modern enzymology have greatly expanded the possibilities of practical use of enzymes, primarily in medicine and the food industry, which is due to their advantages over chemical catalysts: selectivity and stereospecificity of action, the possibility of achieving high rates of conversion of substrates under relatively mild technological conditions, harmlessness to the environment and humans. The microbial producers have proven themselves as a convenient and economical source of biotechnologically important enzyme preparations of hydrolytic action. One of such enzymes is α-galactosidase, which has the ability to cleave terminal α-linked galactosyl residues from a wide range of natural and synthetic compounds. The review presents data on the spread of the enzyme among different groups of microorganisms and provides a comparative description of their catalytic properties. A range of issues related to the physiological role of the enzyme in plant and animal organisms, localization and functional properties in bacteria and fungi are outlined. The place of α-galactosidase of microorganisms in the modern hierarchical classification of glycosidases is shown. The areas of possible use of the enzyme as an efficient tool for the modification of oligo- and polysaccharides in various industries are described.

Dietary α-galactosidase and xylanase to improve the nutritional value of corn-soybean-rapeseed meal diets in broiler chickens

ABSTRACT Two experiments were performed to assess the effects of an enzyme preparation (containing α-galactosidase and xylanase) on chicken performance, carcass traits, footpad dermatitis score, and nutrient digestibility. During first experiment, chickens were fed four diets: (1) control diet (PC): corn and soybean-rapeseed meal; (2) PC supplemented with 350 ppm of the enzyme; (3) Negative control (NC): PC with a 4% reduction of apparent metabolizable energy (AME) and crude protein content; (4) NC supplemented with 500 ppm of the enzyme. In the second experiment, chickens were fed PC or PC + enzyme 350 ppm and a digestibility balance was performed. The enzyme supplementation at 350 and 500 ppm significantly improved the overall feed conversion ratio in PC and NC diet, respectively (P < 0.01). Regarding footpad dermatitis score, animals fed NC + enzyme 500 ppm tended to present a lower value than animals fed NC (P < 0.1). Concerning the digestibility balance, PC + enzyme 350 ppm diet presented a higher feed AME and AMEn value than PC diet (P < 0.05). The enzyme also improved the apparent ileal digestibility (AID) of proline (P < 0.05) and tended to increase AID of cysteine (P < 0.1). In conclusion, the enzyme preparation improves birds feed efficiency by increasing energy utilization.

Green and sustainable techniques to increase the extraction of phenolic compounds from turnip greens by‐products

AbstractThe work was aimed to optimize extraction and recovery of phenolics from turnip greens by‐products using eco‐sustainable techniques based on the use of microwaves, ultrasound, or enzymes and of water as solvent. The optimization of ultrasound‐ and microwave‐assisted extractions was performed using a 4‐factors/3‐levels and a 3‐factors/3‐levels Box–Behnken Design (BBD), respectively and the results of the corresponding trials were fitted to a second order polynomial model. The enzymatic extractions were performed using three different commercial enzymatic preparations, optionally combined with an ultrasound treatment carried out according to the central values of the BBD design. The best results obtained from each green technique were compared with those of the conventional solid–liquid extraction performed with a 70% ethanol aqueous solution. Regarding ultrasounds, the conditions able to maximize the total phenolic concentrations of the extracts (solid–water ratio, 50 g/L; T, 45°C; t, 40 min; power, 24 W) increased the extraction efficiency by about 75% and reduced the extraction times from 2 h to 10 min with respect to the conventional extraction. Concerning microwaves, the optimized conditions (solid‐water ratio, 75 g/L; t, 3 min; power, 160 W) allowed the increase of the extraction efficiency by about 48% and the decrease of the extraction times to just a few minutes. For both techniques, the factor that mainly affected extraction yield and antioxidant activity were “solids‐to‐solvent ratio” and “power,” respectively. According to the results of the enzymatic treatments, the best extraction was that performed with the commercial mix of pectinlyase, polygalacturonase, pectinesterase, and arabinase, which had the same extraction efficiency of microwaves but required longer times (90 min). Furthermore, the combination with ultrasounds did not improve its performances. Extraction technique also affected the phenolic profiles in terms of number and concentration of compounds identified. In conclusion, ultrasounds and microwaves are the best treatments to maximize extraction yield (the first) and minimize extraction time (the second).Practical applicationsThis study presents an approach to the sustainable recovery of phenolics contained in vegetable by‐products that can be adapted to a variety of food waste. It also supplies an overview of the extraction technique efficiency. The industrial adoption of our findings can lead to the following advantages: reduction food waste and/or remove from it compounds that can alter the ecosystem balance; reduction of disposal cost; production of precious ingredients for functional foods/natural cosmetics/natural supplements; obtainment of a new source of income by creating a further activity that can run in parallel with the main production of the company and can serve to diversify investments; improvement of the green image of the company, especially if the energy necessary to the energy needed to power the new process is obtained from renewable sources.

Comparative Investigation of pH-Dependent Availability of Pancreatic Enzyme Preparations In Vitro.

This study aimed to compare different pancreatic enzyme preparations (PEPs) available in Germany regarding particle geometry and size, and to evaluate enzyme activity under physiologically relevant conditions in vitro. Pancreatic endocrine insufficiency is characterized by deficiency of pancreatic enzymes resulting in maldigestion. It is orally treated by pancreatic enzyme replacement therapy. The formulations differ in their physical properties and enzyme release behavior, potentially resulting in inconsistent dosages and poor interchangeability of products. A total of 25 products were analyzed for particle size and number of particles per capsule. Enzyme activities of lipase, amylase, and protease were measured by digestion of olive oil emulsion, starch, and casein, respectively. To analyze enzyme release, gastric environments were simulated by incubating PEPs at pH 1, 4, or 5. Duodenal conditions were simulated by subsequent incubation at pH 6. Regarding physical properties and enzyme release kinetics, considerable differences between different PEPs were found. Furthermore, compared to the label claim, excess lipase activity was observed for most products, reaching up to 148%. These in vitro results suggest poor interchangeability of PEPs, potentially explained by physical and release characteristics. Physicians and patients should be aware of the potential gap between label claims and the real-life performance of different PEPs.

Purification, characterisation and visualisation of soybean protein hydrolysis by aspergillopepsin I from mangrove Aspergillus tubingensis

In order to obtain marine-derived enzymes suitable for protein hydrolysis in acid brewing system, seven species of fungi were obtained from mangrove soil. One of the strains, Aspergillus tubingensis, was determined to have a high acid protease production capacity. Its fermentation broth was purified and the obtained protease was identified as aspergillopepsin I (ATAP) with a molecular weight of 41205 Da. Homology modelling shows that ATAP contains three active sites, each containing to a Zn atom and amino acid residues. The enzyme had the highest relative activity at pH 3.5 and 35–40 °C, and exhibited pH and thermal stability at pH 3.0–3.5 and 20–50 °C. ATAP showed certain salt tolerance. K+ and Zn2+ promoted the enzyme activity, while Mg2+, Cu2+, Co2+, and Fe2+ slightly inhibited the enzyme activity. The results of inhibitors suggest that ATAP belongs to the class of aspartic proteases containing metal atoms. Furthermore, the results of enzymatic hydrolysis of defatted soybean powder showed that the contents of soluble protein, amino nitrogen, free amino acids and the proportion of small molecular peptides (<3 kDa) in the hydrolysate increased significantly. In addition, molecular docking of ATAP and aspergillopepsin I from Aspergillus oryzae 3.042 with soybean globulins (7S and 11S), respectively, showed better hydrolysis of soybean globulins by the former, especially for 7S globulin. Visual analysis indicated the interaction forces between enzymes and soybean globulins were dominated by hydrogen bond and hydrophobic interaction. In conclusion, ATAP may be a candidate as an enzyme preparation for the hydrolysis of soybean proteins.

Investigation of metabolic processes of alcohol yeast during the fermentation of buckwheat-corn wort

To expand the range of competitive alcoholic beverages with original organoleptic properties, it is promising to study the use of new types of plant raw materials in grain distillate technologies. The purpose of this work was to establish the influence of the characteristics of the composition of grain wort prepared with the joint use of an alternative raw material source — buck- wheat and corn, which is widely used in alcohol production, on the metabolic processes of the yeast Saccharomyces cerevisiae 985-T and alcoholic fermentation. The objects of the study were buckwheat and corn; enzyme preparations — sources of amylases, xylanases, β-glucanases and proteases; samples of grain wort, mash and mash distillates. The prospects of introducing mixed grain media prepared using non-traditional buckwheat raw materials into the technology of original alcoholic bever- ages are substantiated. It was shown that the use of buckwheat as a source of biocomplete protein, essential amino acids and minerals together with corn containing a high level of starch and a low level of non-starch polysaccharides contributed both to an increase in the yield of alcohol and a change in the quantitative content of secondary metabolites in the composition of volatile impurities. It was found that an increase in the concentration of soluble carbohydrates in the wort and a decrease in its viscosity by 15.5–40.3% occurred due to the inclusion of corn in the composition of the grain mixture, and the enrichment of the wort with nitrogen assimilated by yeast by 19.0–41.8% — as a result adding buckwheat. The optimal ratio of corn and buckwheat in the composition of the grain mixture (7:3) was selected, which made it possible to improve the biochemical and technological parameters of grain must, increase the efficiency of the vital processes of yeast and alcoholic fermentation, ensure an increase in the yield of alcohol by 1.8%, reduce the formation of side metabolites, especially higher alcohols, and change their composition in the direction of increasing the proportion of aldehydes and esters, which can have a positive effect on the organoleptic characteristics of the distillate.

Study of the Wobenzym Enzyme Preparation Effect on the Formation of Bacterial Biofilms

Study of the Wobenzym Enzyme Preparation Effect on the Formation of Bacterial Biofilms

Application of simultaneous rapeseed oil extraction and interesterification with methyl formate using enzymatic catalyst

A novel method of interesterification of rapeseed oil utilising methyl fomate and an enzymatic catalyst to produce biodiesel without the need for glycerol separation was researched. Using the enzyme preparation Lipozyme TL IM as a catalyst, the simultaneous processes of oil extraction from rapeseed and interesterification in-situ were investigated. Three independent variables were assessed for their interaction and impact on the yield of rapeseed methyl esters: the mass ratio of methyl formate to rapeseed, the time, and the amount of catalyst. Utilising surface response methodology, process optimisation was performed, and a model explaining the impact of independent variables on the yield of rapeseed methyl esters was developed. Lab testing has verified that the optimal process parameters have been identified, resulting in a 94.24 % rapeseed methyl ester yield. Using a 48:1 mass ratio of methyl formate to rapeseed and 23.33 % of the enzymatic catalyst in 64.5 h produced the highest yield. The reaction product contained conventional biodiesel (rapeseed methyl esters) along with mono-, di-, and triformyl glycerides. The interesterification product's physical and chemical characteristics were identified, and the resulting quality indicators were compared with the specifications of standards for biodiesel and mineral diesel fuel.

Microbiological indicators of cottage cheese using different rennet leavens

Rennet cheeses occupy an important place in the diets of the population of Ukraine. The technology of cheese production depends both on the quality of raw materials and on the quality of the enzymes used to curdle milk. Therefore, the study of the effect of rennet enzymes obtained by improved biotechnology on the microbial state of the finished product is of scientific and practical importance. III groups of samples (n = 3) were formed to conduct the experiment. Cow's milk for research was collected from clinically healthy cows during the calving period. In the control group of samples, rennet enzyme of microbial origin was used for curdling milk. In the 1st experimental group of samples, an enzyme preparation was used, extracted from the rennet of dairy calves according to the method of Yu. Ya. Svyridenko In the II experimental group, an enzyme preparation obtained by the method of extraction according to the method of was used. S. V. Merzlova. Laboratory research was carried out in the conditions of the Research Institute of Food Technologies and Technologies of Processing Livestock Products and the Laboratory of Microbiological Research Methods of the Department of Microbiology of the Bilotserk National Agrarian University, which is certified according to (DSTU ISO 10012:2005). To determine the qualitative and quantitative microbial composition, culture was carried out from cheeses obtained with the help of various enzyme preparations. Microbiological research was carried out using the methods defined by DSaNPiN 4.4.5-078-2001 “Microbiological standards and methods of control of food products”. To determine bacterial insemination, two nutrient media such as Lees agar and Streptococcus thermophilus agar were used. The method of serial dilutions was used for seeding the suspension. Sowing was carried out by applying 1.0 cm³ of suspension (dilutions from 1 to 10-5) in melted and cooled agar in Petri dishes, followed by thermostating for 48 hours at 37 °.

Enzymatic Preparation, In-Depth Molecular Analysis, and In Vitro Digestion Simulation of Palmitoleic Acid (ω-7)-Enriched Fish Oil Triacylglycerols.

In this study, an enzymatic reaction was developed for synthesizing pure triacylglycerols (TAG) with a high content of palmitoleic acid (POA) using fish byproduct oil. The characteristics of synthesized structural TAGs rich in POA (POA-TAG) were analyzed in detail through ultrahigh-performance liquid chromatography Q Exactive orbitrap mass spectrometry. Optimal conditions were thoroughly investigated and determined for reaction systems, including the use of Lipozyme TL IM and Novozym 435, 15 wt % lipase loading, substrate mass ratio of 1:3, and water content of 2.5 and 0.5 wt %, respectively, resulting in yields of 67.50 and 67.45% for POA-TAG, respectively. Multivariate statistical analysis revealed that TAG 16:1/16:1/20:4, TAG 16:1/16:1/16:1, TAG 16:1/16:1/18:1, and TAG 16:0/16:1/18:1 were the main variables in Lipozyme TL IM and Novozym 435 enzyme-catalyzed products under different water content conditions. Finally, the fate of POA-TAG across the gastrointestinal tract was simulated using an in vitro digestion model. The results showed that the maximum release of free fatty acids and apparent rate constants were 71.44% and 0.0347 s-1, respectively, for POA-TAG lipids, and the physical and structural characteristics during digestion depended on their microenvironments. These findings provide a theoretical basis for studying the rational design of POA-structural lipids and exploring the nutritional and functional benefits of POA products.

Effect of a Phytomineral Complex and an Enzyme Preparation on the Absorption of Nutrients and the Energy Balance of Calves' Diet

Effect of a Phytomineral Complex and an Enzyme Preparation on the Absorption of Nutrients and the Energy Balance of Calves' Diet

Safety evaluation of the food enzyme preparation D-psicose 3-epimerase from the non-genetically modified Microbacterium foliorum strain SYG27B.

This assessment addresses a food enzyme preparation consisting of the immobilised non-viable cells of the non-genetically modified bacterium identified by the applicant (Samyang Corporation) as Microbacterium foliorum strain SYG27B. This strain produces the enzyme D-psicose 3-epimerase (EC 5.1.3.30). The food enzyme preparation is used for the isomerisation of fructose to produce the speciality carbohydrate D-allulose (synonym D-psicose). Since the hazard identification and characterisation could not be made and the identity of the production organism could not be established, the Panel was unable to complete the assessment of this food enzyme preparation containing D-psicose 3-epimerase.

Evaluation of Heavy Metal Concentrations in Enzyme Embedded Poly Lactic Acid (EPLA) by ICP-OES: Lipase from Candida Rugosa.

Abstract: Enzymes like lipases are essential for catalyzing important reactions in the fields of biotechnology and industrial operations. For quality control and safety evaluations, however, the quantification of these contaminants is crucial because the presence of heavy metals in enzyme preparations can negatively affect their activity and stability. Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES), a key component of this investigation, is used to measure the levels of heavy metals in lipase enzyme preparations embedded in polylactic acid (PLA). The lipase enzyme being studied comes from Candida rugosa, which is well-known for its considerable industrial applications. According to preliminary findings, the lipase enzyme is successfully protected from external heavy metal pollutants by the encapsulating technique, maintaining its enzymatic activity and stability. The lipase-PLA composite had only minimal quantities of heavy metals, according to the ICP-OES study. The research's conclusions show great potential for the creation of reliable and contaminant-free lipase enzyme preparations, which will increase their suitability for usage in a variety of industrial processes and encourage the use of biodegradable polymers, supporting environmental sustainability. By highlighting the significance of quality control and safety assessment through the determination of heavy metal concentrations, this research contributes to the larger field of enzyme biotechnology. It also highlights the potential of Candida Rugosa lipase implanted in PLA matrices for eco-friendly and sustainable biocatalytic applications in sectors ranging from food and pharmaceuticals to biofuel generation and other biodegradable polymers.

Streptococcus thermophilus: A Source of Postbiotics Displaying Anti-Inflammatory Effects in THP 1 Macrophages.

In addition to traditional use in fermented dairy products, S. thermophilus also exhibits anti-inflammatory properties both in live and heat-inactivated form. Recent studies have highlighted that some hydrolysates from surface proteins of S. thermophilus could be responsible partially for overall anti-inflammatory activity of this bacterium. It was hypothesized that anti-inflammatory activity could also be attributed to peptides resulting from the digestion of intracellular proteins of S. thermophilus. Therefore, total intracellular proteins (TIP) from two phenotypically different strains, LMD-9 and CNRZ-21N, were recovered by sonication followed by ammonium sulphate precipitation. The molecular masses of the TIP of both strains were very close to each other as observed by SDS-PAGE. The TIP were fractionated by size exclusion fast protein liquid chromatography to obtain a 3-10 kDa intracellular protein (IP) fraction, which was then hydrolysed with pancreatic enzyme preparation, Corolase PP. The hydrolysed IP fraction from each strain exhibited anti-inflammatory activity by modulating pro-inflammatory mediators, particularly IL-1β in LPS-stimulated THP-1 macrophages. However, a decrease in IL-8 secretion was only observed with hydrolysed IP fraction from CNRZ-21N, indicating that strain could be an important parameter in obtaining active hydrolysates. Results showed that peptides from the 3-10 kDa IP fraction of S. thermophilus could therefore be considered as postbiotics with potential beneficial effects on human health. Thus, it can be used as a promising bioactive ingredient for the development of functional foods to prevent low-grade inflammation.

BIOTECHNOLOGICAL PROCESSING OF LOW-GRADE MEAT WITH ENZYME PREPARATIONS

Biotechnological methods for processing raw materials in the meat industry are associated with the creation of advanced technologies. Domestic and world experience indicate the advisability of using enzymes in the meat industry to accelerate the maturation processes and increase the quality of semi-finished products. In order to intensify technological processes, increase the nutritional and biological value of finished products, enzyme preparations are used in the process of processing low-grade meat raw materials. Currently, herbal enzyme preparations phytosin, papain, bromelain, etc. are widely used. Processing meat with enzymes improves the consistency of meat, softens the structure of rough and strong muscle fibers and connective tissue; helps to increase the degree of digestibility of the product; improves taste, smell and color and accelerates the ripening process of meat [1].Enzymes are participants in both traditional and new technological processes used in food production. The muscles of farm animals are characterized by low concentrations of intracellular enzymes. Some anatomical parts of the carcass are characterized by a high content of connective tissue. This determines the toughness of such meat and its slow maturation. Beef under normal conditions matures after 10-14 days of aging at a temperature of 2-4°C. After treatment with enzymes, the meat matures in 1-2 days. The main purpose of aging beef is to break down the muscle fiber structure and enhance the natural flavor of the meat [2].Processing low-grade meat with plant enzymes will make it possible to use parts of the carcass that are full in composition, but have naturally increased rigidity: meat from the hind legs, shoulder blades, and brisket. Processing meat with a plant enzyme preparation leads to significant destructive changes that provide an effective softening effect, and is consistent with the obtained assessments of physicochemical and functional technological properties [3].The use of enzyme preparations has a positive effect on the tenderness, juiciness, nutritional value of raw materials, the formation of the required level of water-binding and water-holding capacity, and improves organoleptic characteristics due to the targeted effect of plant enzymes and enzymatic preparations on the components of muscle tissue [4].

Determination of malvidin-3,5-diglucoside content in wines from Cabernet Cortis and three Italian-resistant hybrids, with preliminary evaluation of oenological glycosidases for enzyme-induced breakdown of malvidin-3,5-diglucoside and malvidin-3-glucoside

ABSTRACT The content of malvin (malvidin-3,5-diglucoside) was determined in a set of wines obtained from Cabernet Cortis and other three recently introduced grape-resistant hybrids (Cabernet Volos, Merlot Khantus and Merlot Khorus) produced in South Tyrol (Italy), to establish their conformity to legal requirements and suggest winemaking approaches for their production and use. Different skin maceration times and ageing periods were considered for the wines investigated. Malvin content exceeded the limit of 15 mg/L, imposed by the Italian government for the commercialization of wines, in 18 out of 21 samples and showed a significant decrease during wine ageing (by about 40–50% every 12-month period) with the scarce effect of maceration time and fermentation temperature. Single-cultivar wines became suitable for commercialization after ca. 7 years ageing, following traditional winemaking approaches. The use of two commercial enzymatic pectolytic preparations indicated for aroma enhancement and possessing β-glucosidase activity was also investigated at two different dosages, to increase the degradation rate of malvin in wines after winemaking. They are unsuitable for significant malvin content decrease within a 6-month time lapse.

ИССЛЕДОВАНИЕ ПРОЦЕССА ОСВЕТЛЕНИЯ ЯБЛОЧНОГО СУСЛА С ПРИМЕНЕНИЕМ РАЗЛИЧНЫХ ВСПОМОГАТЕЛЬНЫХ СРЕДСТВ

The quality of clarification of apple must from various varieties of apples of domestic and foreign breeding, different ripening periods, growing at the Research and Breeding Collection of Genetic Resources of Horticultural Crops, located in the Central Joint Stock Company, Krasnodar, was studied. Sampling of apples was carried out at optimal ripeness from different sides of the tree crown in relation to the cardinal directions. Apple processing was carried out using a crusher-grinder, followed by pressing the pulp on a hydraulic press. The enzyme preparations SQzyme PCL, Grainzyme NL and Fructozyme R were used in the experiments. Apple must was clarified using bentonite (BENTOVIN), plant (pea) and animal (gelatin) protein. As a result of the studies, it was established that self-clarification of the must without the use of enzyme preparations was slow. Slow self-clarification with the formation of voluminous loose and mobile sediments was observed only in certain variants (Ekzotika, Orfey, Liberti, Renet Platona). The addition of enzyme preparations, especially SQzyme PCL, contributed to an increase in must yield by 12-17 % relative to the control. The most “responsive” to the use of enzyme preparations were apples of the varieties Dzhin, Ekzotica, Orfey, Margo, Prikubanskoe, Bagryanets Kubani, Liberti, Renet Platona, forms 12/1-20-16 and 12/1-20-33. With the addition of enzyme preparations in the pulp, the rate of must extraction increased. Gradual clarification was noted in the next 3-4 hours. The greatest increase in must yield was noted during the processing of apple varieties such as Enterprise, Margo, Ketni, Renet Platona – by 12-17 % compared to the control (without the use of enzyme preparations). The use of only one sorbent – bentonite, animal or vegetable protein – did not lead to high-quality clarification of the must at the given dosages. At the same time, complex processing made it possible to significantly improve the quality of clarification and reduce the turbidity of the must. The highest quality clarification of the must, regardless of the apple variety, was obtained by complex treatment of the pulp with enzyme preparations followed by dosing of proteins and bentonite. Key words: APPLE MUST, CLARIFICATION, ENZYME PREPARATIONS, BENTONITE, PROTEIN SORBENTS