Fruit growing
and viticulture of South Russia
The publication presents the results of studies to determine the population size of grape thrips Drepanothrips reuteri Uzel and the extent of distribution of on the Don under different meteorological conditions. The studies were carried out in 2021 and 2022 in the conditions of two agrocenoses of Novocherkassk and Nizhnekundryuchensky Branches of the experimental field of the All-Russian Research Ya. I. Potapenko Institute for Viticulture and Winemaking. The subject of the study was the dynamics of the prevalence and harmfulness of grape thrips on the technical grape varieties Tsvetochnyi and Cabernet severnyi, in an uncovered culture. In the context of the widespread distribution of sugescent pests of grapes, the issue of protecting production plantings and improved basic plantings of the mother plant from them is acute, using the method of monitoring studies to signal the population size using flower traps. Therefore, the study of the development features of grape thrips, both in the conditions of the mother plant of basic plants and fruit-bearing vineyards and their influence on the economically valuable traits of grapes, is relevant. Grape thrips is a relatively new species for grape plants in the Rostov region, migrating from abandoned areas with weeds adjacent to the vineyards in search of food. To contain the prevalence of the grape thrips population below the economically significant threshold of harmfulness in agrocenoses, it is necessary to conduct timely phytosanitary monitoring. Under the conditions of two agrocenoses in 2021 and 2022, two generations of grape thrips developed during the growing season: the first at the end of May, the second at the end of June. The intensity of damage to plants of two grape varieties by grape thrips was not significant and did not exceed the economically significant threshold of harmfulness, so it was decided not to carry out chemical treatments. The presence of a stable number of pest individuals suggests that the population may be capable of wider distribution.
As known, tomatoes contain a fairly large amount of biologically valuable substances in their composition. Consumers prefer tomatoes in fresh form. However, being a climacteric crop, tomatoes differ during storage and maturation by a high rate of respiration and evaporation of moisture, which leads to a decrease in valuable nutrients, deterioration in quality, over-ripening and rapid aging, which as a result reduces the marketable appearance of products. Traditional methods of processing tomatoes before storage are not always effective enough to maintain the quality of tomato fruits at the proper level, since it is not always possible to store tomatoes at the recommended low temperature, the necessary relative humidity, etc. In order to increase the storage time of tomatoes while maintaining their quality and safety, it is necessary to search for new modern methods of fruit processing before storage. In this regard, an overview of existing traditional technologies, as well as modern and promising techniques and methods for preparing fresh tomatoes for storage, contributing to the reduction of quantitative losses, preserving qualitative characteristics, is carried out. The most promising methods of preliminary preparation of tomatoes for storage, providing a high level of physical-chemical, organoleptic and microbiological indicators that ensure the safety of stored products are: treatment with ethylene biosynthesis inhibitors and ethylene absorbers, ozonation, modified gas atmosphere, electric field and ultrasound treatment, the use of biological products, the use of active packaging, antimicrobial film-forming coatings, etc. The article describes the work of both domestic and foreign researchers.
The work shows the results of the influence of the degree of maturity, storage parameters and processing method on the techno-chemical parameters of zucchini. Thus, during the organoleptic assessment of zucchini of different degrees of maturity, stored at a temperature of 8 to 10 ºC for 18 days, it was found that ELF EMF treatment allows maintaining organoleptic quality indicators. At the same time, the average expert assessment score for zucchini of the 1st degree of maturity treated with ELF EMF was the maximum. The maximum weight loss was observed in zucchini of the 1st degree of maturity, the minimum in the 3rd degree of maturity. When storing zucchini, weight loss depends on the degree of maturity. The minimum weight loss of zucchini without treatment was noted at the 3rd degree of maturity, and the greatest at the 1st degree of maturity. It has been established that when storing zucchini, ELF EMF treatment can reduce weight loss compared to the control sample for zucchini of the 1st and 2nd degrees of maturity. When studying changes in the biochemical parameters of zucchini depending on the degree of maturity, the method of processing samples and storage conditions, it was found that they decrease over time. During storage, ELF EMF treatment can reduce the loss of soluble solids by 0.2-0.5 %, and when stored in a refrigerator by 0.2-0.3 %, depending on the degree of maturity. It has also been established that to assess the degree of maturity of zucchini, the iodine-starch method can be used, the essence of which lies in the ability of starch to give a blue-black color in an iodine solution: hydrolysis of starch during the ripening of zucchini proceeds in the direction from the center to the periphery of the seed chamber, which makes it possible to assess the degree of maturity zucchini fruits.
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.
In this work, an attempt has been made to study the possibility of using carbon dioxide extracts from plant raw materials as an additive to improve the taste and aromatic parameters of a grape-containing drink. Advancing the technology of juices and drink is mainly aimed at improving their stability indicators, preserving and increasing the content of biologically active substances. Considerable attention in the production conditions is paid to the use of preservation agents, especially if this applies to products intended for infant food. In this work, methods of chemical analysis, capillary electrophoresis, gas chromatography using a capillary column were used to assess the general parameters of the component composition of grape juice. Experiments on the modification of grape drink used carbon dioxide extracts produced by OOO Karavan (Krasnodar). To compare the component composition of the extracts, the substances were determined by group characteristics. It has been shown that the use of CO2 extracts increases the stability of grape-containing drink. The effect on the taste, color and aroma of grape juices from Aligote, Riesling varieties was investigated at the following doses of vegetable extracts 0.005 %, 0.01 % and 0.02 %. The main condition for the use of the carbon dioxide extract additive has been determined it should not change the taste and aromatic characteristics of grape-containing drink. Among the selected plant extracts, only the addition of 0.005 % of horse chestnut or coconut allowed to ensure the stability of the product and did not change its taste characteristic. The use of these carbon dioxide extracts allowed to increase the stability of grape-containing drink within the warranty period and contributed to its clarification.