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- ДокументEFFECT OF CHITOSAN PRETREATMENT ON THE QUALITY OF STRAWBERRIES DURING COLD STORAGE(2021) A. Blahopoluchna, N. LiakhovskaThe paper is focused on improving the technology of storing strawberries. It has been investigated how pretreatment of berries with aqueous solutions of low-molecular-weight chitosan of three concentrations (0.1%, 0.3%, 0.5%) affects the quality parameters of strawberries during refrigeration. The treated berries and the reference (untreated sample) were stored in 500 g perforated plastic containers at 0±2°C for 14 days. It has been found that strawberries treated with chitosan solutions had significantly smaller weight loss than the reference. At the end of storage, this parameter was 9.7% in the reference and 7.0–8.6% in the treated berries. It has been established that the respiration rate of the strawberries decreased sharply on the first day, which was caused by refrigerated storage, and continued to decline until the end of storage. Finally, this parameter attained the value 3.3 mg CO2/kg-1h-1in the reference and 2.2–3.0 mg CO2/kg-1h-1 in the treated berries. The hardness of the strawberries at the end of storage was 0.10–0.14 kg/cm2. The change in the lustre level of the berries has been observed. It has been established that on the 14th day of storage, the surface of the untreated berries was dull. The best characteristics have been observed for treatment at the chitosan concentration 0.5%. The effect of chitosan films on the sensory characteristics of berries has been investigated. It has been found that the pretreatment did not impair the taste of the berries. The results of the tasting evaluation indicate that the taste, aroma, and colour were better in the variants with the treatment concentrations 0.3 and 0.5%. However, as for the appearance and consistency, the experts preferred the berries treated at the concentration 0.5%. After two weeks’ storage, the strawberries have been found to be damaged by four fungal diseases. The infections found in the samples were Botrytis cinerea (grey mould), Rhizopus stolonifer (black mould), Whetzelinia sclerotiorum (white mould), and Penicillium spp. It has been established that pretreatment of strawberries with chitosan solutions reduces the development of phytopathogenic diseases. It has been shown that chitosan-based edible coatings have a positive effect on strawberries, increasing their shelf life and improving their quality. A conclusion has been drawn about the technology of application of chitosan solutions and about their concentrations.
- ДокументGEROPROTECTIVE PROPERTIES OF POLYPHENOLIC COMPOUNDS OF FOOD PLANTS(2021) P. Oliіnyk, D. Voronenko, R. Lysiuk, A. Oliinyk, S. OliinykPeople’s ageing causes economic and social problems all over the world. The article presents the results of the analysis of modern research on ways and means that can eliminate the causes of ageing, prolong the active longevity and working ability of the elderly. It has been established that human health and longevity depend on the specific features of a person’s nutrition and are affected by micronutrient deficiency in the body caused by unbalanced diet. Considering the free radical theory of ageing, which is based on the chemical nature and ubiquity of free radicals, it has been found that consumption of plant foods rich in antioxidants prevents oxidative damage to cellular structures, which is caused by reactive oxygen species. It has been demonstrated that well-known plant antioxidants, such as flavonoids and other polyphenolic compounds, have a protective effect. They modulate energy metabolism in a way conducive to well-being and longevity, and reduce the risk of chronic diseases and ageing. It has been established that the antioxidant effect of flavonoids involves scavenging of free lipoperoxide radicals, inhibition of nitric oxide production, inactivation of peroxynitrite and other oxidants, inhibition of xanthine oxidase and other radical-producing enzymes, chelation of metals. Neuroprotective and radioprotective properties of flavonoids have been revealed. Flavonoids can inhibit regulatory enzymes or transcription factors that are important for the control of inflammatory mediators, affect oxidative stress through DNA interactions, and enhance genomic stability. Combinations of polyphenols can exhibit synergistic or additive beneficial effects. It has been shown that the rational use of plant-based diets rich in polyphenolic compounds helps to reduce the total mortality rate and, in particular, mortality from coronary heart disease, to maintain sustainable weight management, to decrease the frequency and severity of high-risk conditions such as obesity, hyperglycaemia, hypertension, hyperlipidemia, and improve the general condition in cases of long-neglected cardiovascular diseases and diabetes.
- ДокументOptimisation of conditions for deacetylation of chitin-containing raw materials(2021) O. Pavlova, M. TrusovaThe paper describes the differences between chitosan and chitin, and reviews works by foreign scientists on obtaining chitosan from various raw materials. Methods of modifying chitosan and obtaining combined sorbents have been analysed. It has been studied whether chitosan is applicable in the technology of wines and alcoholic beverages as a sorbent. The purpose of the study was determining the optimal conditions of the deacetylation stage to obtain chitosan with the best sorption properties from Aspergillus niger biomass. A three-factor experiment has been carried out. It involved obtaining 27 samples of chitosan using sequential four-step acid-base hydrolysis under various conditions of the deacetylation stage. The deacetylation process was optimised under alkaline conditions depending on the alkali concentration, processing temperature, and exposure. For each of the samples obtained, the adsorption activity, specific surface area, and distribution coefficient in the sorbent–sorbate system have been determined. The degrees of deacetylation of all chitosan samples have been determined by potentiometric titration. The study has resulted in determining the optimal conditions for the deacetylation stage: processing temperature 110–130°C, sodium hydroxide concentration 27–36 g/dm3, exposure 45 to 65 minutes. The sample deacetylated at the temperature 120 °C, alkali concentration 30 g/dm3, and exposure 45 minutes has shown the best adsorption activity values: the adsorption activity for methyl orange 347.96 mg/g, the specific surface area of the sorbent samples 0.52·105 m2/g, the distribution coefficient in the sorbent–sorbate system 3.29·10-3 ml/g. This sample had the highest degree of deacetylation, 43.6%. The sample has been analysed using IR spectroscopy, and its main characteristic frequencies have been studied. It has been concluded that the sample obtained was equivalent to the reference chitosan
- ДокументTHE BOUILLON TABLES FROM TURKEY: DETERMINATON OF CIS-TRANS FATTY ACID PROFILES BY CAPILLARY GAS CHROMATOGRAPHY(2021) Harun DıramanNowadays, commmercial bouillon tablets are mostly used as a flavor enhancer substant or an instant product in Turkish cuisine. As chemical structure, Trans FAs are unsaturated fatty acids having at least one double bond in its trans geometric configuration. Trans FA are occured by the partial hydrogenation of vegetable oils in the manufacturing of margarine and vegetable shortening. In this study, industrially produced commmercial bouillon tablet (n=14) samples from Turkey were analyzed by capillary (DB 23 column) gas chromatography method and an under controlled temperature oven programm with particular emphasis on cis–trans fatty acid profiles. The bouillon samples were collected as two goups (first group containing animal additives [AAB n=12] and second group including vegatable additives [VAB n=2]). There is no detailed information on fatty acid (FA) compounds, including trans fatty acids (TFAs), of consumed several commercial boullions in Turkey. There is no “trans fatty acid-free” declaration on various bouillon labels in Turkey. Large variations were observed among the cis–trans FA profiles of the boullion samples from Turkey,despite the fact that the samples are produced in the same production conditions.The palmitic (PAM) levels (predominant cis saturated FAs for all samples) of AAB samples (32.63–44.44%) were more high rather than the VAB samples (47.62–50.64%). Other major saturated FAs for AAB and VAB samples were determined stearic ( (5.28–9.90% AAB and 6.33–6.73% VAB), lauric (0.19– 5.84% AAB and 1.13–1.30% VAB) and myristic acids (0.86–2.61% AAB and 1.39–1.45% VAB).The changes of oleic (OLA) acid (from other predominant cis monounsaturated FA) of VAB samples (30.75–33.45%) were high than those of AABs (12.64–29.35%). The ranges of LO, an essential /nutritional fatty acid and the predominant FA of PUFAs, and PUFAs of AAB – except two samples– commercial bouillon samples (0.45–9.82% and 0.45–9.97% ) were low rather than VAA samples (7.97–8.14% and 8.14–8.35 %). Conjugated Linoleic (CLA) FAs, having nutritional FAs having anti-carcinogenic, antioxidative and anti-atherosclerotic effects, were determined in small amounts for only six samples (0.03% to 0.06% ). Elaidic acid (C18:1 trans acid) content, the mainly trans FA in all boullion, was within the range of 20.00–27.32% in the AAB samples, and it was significantly higher than the range in VAB samples (0.08–0.14%). Total trans fatty acids (TFAs) were another important major (second) FAs for all bouillon samples. The changes of Trans/Cis ratio ranged between 0.26 and 0.50 for AAB samples but VB samples has a little values from 0.002 to 0.003. Turkish vegetable boullion. samples have low total trans FA contents (0.19–0.26%) than the animal boullion samples (20.19–28.78%).There are a large variation and significant (P<0.05) differences were statistically determined among major cis FAs (PAM, SA, OLA, LO and LN) and their involved parameters (SFAs, MUFAs and PUFAs). The consumed several commercial boullions in Turkey were classified and characterized chemometric method (Principal Component Analysis, PCA) based on some fatty acid profiles and their parameters. Applying PCA to the all bouillon samples data determined the percentage of total variance explained by the first two PCs were 49.3% and 21.8% (totally 71.1%), respectively.
- ДокументPreservation of rapana meat by the irradiation technology(2021) T. Lebska, L. Bal-Prylypko, T. Kovalinska, V. Sakhno, Ye. Bondarenko, E. Mikhneva, O. Kravchenko, V. BondarenkoThe article considers the technology of maturing preserves from the meat of the Black Sea gastropod mollusc Rapana thomasiana using irradiation technologies. The methods of improving the technology of processing rapana meat have been studied in order to ensure long-term storage of the finished product without using artificial preservatives. The technology is based on the preliminary preparation of the semi-finished product, which includes defrosting, sorting, cutting, washing, inspection, portioning, blanching, and cooling. It has been studied how different methods of preprocessing the raw material affect the mechanostructural properties of rapana preserves. Blanching the meat of rapana has proved practical. Acetic acid has been shown to increase the sensitivity of rapana muscle tissue to picowaves. It has been found effective to soften rapana muscle tissue by marinating with acetic acid and by using picowave irradiation in various doses (2 to 10 kGy) for 60 s. The choice of the recommended dose of 2 kGy has been substantiated. It has been established that after picowave processing, the sensory properties of the finished product do not change. The system of picowave processing of preserved meat to soften its inhomogeneous structure has been described. The shift of kinetic energy in the electronic field using thin targets to form the required radiation field of different sizes has been used. This has allowed influencing the inhomogeneous structure of the raw material. It has been proved that after picowave irradiation with the dose 2 kGy, the preserved rapana meat is microbiologically safe and can be stored for 90 days at 4±2°С. The technological scheme of making preserves from rapana meat using PWP has been provided. The studies indicate that using the irradiation technology is practical, as it ensures the maturation of low-maturing aquatic organisms, extends the shelf life of food, guarantees safety and high quality