The Study of Thermal Reversibility of the Freezing-defrost Process of Browned Onion

The features and dynamics of the freezing-defrost processes of the studied sample of browned onion were established and studied. At the research it was revealed, that at freezing temperature –20 °С the value of maximal freezing speed does not change.The process of defrost of browned onion was carried out using calorimeter with the reverse connection on temperature and PID-regulator, on the temperature curve of its freezing. It was determined, that the process of defrost of the studied sample needs more heat that is educed at freezing. The modes of stepped defrost that testify to the possibility of thermal reversibility of freezing process were experimentally established.The direct dependence of educed and consumed heat quantity on the mode of thermal processing of studied sample was revealed. The more moisture was eliminated from the food product, the less heat must be consumed for defrost. The analogous dependence is typical also for the freezing process.The received data can be used for determination of the rational modes of freezing and defrost of the browned onion

Conducting Commodity Assessment of Lactose Free and Ordinary (Lactose) Yoghurts on the Example of Ukrainian Producers

The objects of research were 5 lactose-free and 5 ordinary (lactose) yoghurts presented on the market in Kharkiv (Ukraine). When carrying out research work, a complex of generally accepted chemical, physicochemical, mathematical methods was used, corrected for the merchandising evaluation of yoghurts.The first stage of the study was to conduct a comparative organoleptic assessment of selected samples, paying attention to the uniformity of consistency, the presence of inclusions, the presence of foreign odors and flavors, as well as the uniformity of color.According to the results of a comparative organoleptic quality assessment, it was found that all the studied samples of yoghurts had the same pure, sour milk taste, without extraneous odors unusual for the product, with a well-expressed sour taste. The results of the consistency assessment indicate that on the surface of sample No. 3 there was a separation of whey and a curd, with an undisturbed clot, which occurred due to the fact that lactose-free yoghurt was produced by the thermostatic method.The second stage of the comparative merchandising assessment of selected yoghurt samples was to determine their main physical and chemical parameters in accordance with the requirements of DSTU 4343:2004 «Yoghurts. General technical requirements». The analysis of the physicochemical indicators of the studied samples showed that only sample 1 had deviations from the requirements of the normative and technical documentation, namely, the content of the mass fraction of dry substances was lower by 0.3 %, which indicates non-compliance with the product manufacturing technology. The content of the mass fraction of dry substances of other samples was within acceptable limits. When determining the content of titratable and active acidity, the mass fraction of fat in yoghurts, it was found that all the samples under study did not deviate from the requirements of the regulatory and technical documentation.It was found that carrying out a commodity assessment (determination of organoleptic and physicochemical indicators) makes it possible to obtain a set of results on the freshness of the studied samples of lactose-free and ordinary (lactose) yoghurts

Cryoscopic and Microbiological Study of the Semi­finished Product for Making a Smoothie Drink

The dynamics of freezing a semi-finished product for making a smoothie drink was investigated. We have chosen, as the subject of present study, a semi-finished product whose production technology included strawberry, dried apple, and oat flakes.By using a low temperature calorimeter, crystallization ranges for the examined semi-finished product, as well as the amount of frozen moisture, which was 68.6 %, were identified. It is established that freezing at −20±2 °C contributes to the complete preservation of the sample, and its further storing at the temperature within such limits ensures its storage over a long period of time. It was also experimentally established that the curves of freezing and defrosting of the sample do not coincide, that is, the character of temperature dependence during freezing and defrosting is different. This testifies to the irreversibility of plant tissue during ice formation and thawing.A reduction in the total microbial contamination over a long refrigeration storing is established, which indicates a negative effect of cold on the viability of microorganisms. The amount of mesophilic-aerobic and optionally anaerobic microorganisms in 30, 60, 90, 180, and 270 days of refrigeration at −18±2 °C is significantly reduced compared to freshly prepared. The amount of yeast and mild fungi also decreases during storage. It is important to comply with sanitary and hygienic standards during production, packaging, storing, and selling, since the complete extinction of the microflora does not occur.The development and active introduction of effective freezing technologies, low temperature storage, and processing of fruits and berries would contribute to solving a task on the balanced nutrition of people, reducing the level of diseases, improving quality of life. In addition, the introduction of such technologies would significantly enlarge the base of local processing industry whose development, in turn, would contribute to the development of agricultural production in a given region.The data obtained data could be applied to determine the rational freezing and defrosting modes for a semi-finished product and would make it possible to extend the assortment of frozen products

Effect of Sautéing of Onion on Its Storage at Low Temperatures

We studied dynamics of freezing and defrosting of sautéed onion, determined its acidic and peroxide number, which was stored during 30 days at temperature of –18 °C. The change in anatomical structure of frozen onion depending on thermal pre–treatment was examined.The technology of production of frozen vegetable mixes implies the use of thermal treatment; therefore, selecting the method of canning, which will make it possible to maximally preserve useful substances of chemical composition of a product, is relevant.As the object of experiment we used fresh and frozen sautéed onionIt was found as a result that at temperature of freezing – 20 °C, the value of maximum speed of freezing practically does not change; this indicates that the rate of cooling is not limited by thermal and physical properties of the sample. We also experimentally determined the increase in acid number in the process of refrigeration storage during 30 days and the decrease in peroxide number in the examined samples of sautéed and frozen onion.It was revealed that the cells of onion after sautéing changed their form and structure: they do not have a clear form and orderliness; the breaks are visible at the contours of the walls of cells. The luminescent formations after sautéing of onion change their form as a result of deformation of cellular membranesThe obtained data may be used for providing high quality of the frozen vegetable mixes for soups and for determining rational regimes of freezing and defrosting of sautéed onion in their composition. Adding sautéed onion to the frozen vegetable mixes is expedient and will not change organoleptic properties of a product; it will not accelerate the oxidation processes of fats, but will only help to preserve the integrity of shape and delicate consistency of onion in a soup prepared from such a mix

Investigation of Change of Quality Indicators of Gluten-free Bread During Storage

The content of vitamins and microelements in vegetable powders, flour of legumes and in bread made with their use was investigated. The degree of staling of gluten-free bread was determined and, on the basis of the obtained regularities, the timing of the sale of special bread was scientifically substantiated and experimentally confirmed. The relevance of the studies carried out is due to the shortage of special dietary consumption products, the under-filling of the market for which is about 23 % of the total production. As a result of the study, it was found that the composition of the powder from carrots of the Daucus carota variety and the powder from the beets of the Beta vulgaris L. variety contained vitamins: А, Е, С, В1, В5, В6, В9, В12, K, РР and trace elements: Ca, Mg, Fe, Cu, I, Se, Zn. Vitamins A, E, C, В6, В9, В12 and microelements: Mg, Fe, Cu, I, Se, Zn are found in soy and chickpea flour. The degree of nutrient retention after the manufacture of specialized bread and after 72 hours of storage has been determined. Losses occur in the content of vitamins A, E, C and trace elements Fe, Cu. After 72 hours of storage, the developed types of bread, provided that 100 g per day are consumed, cover 50 % of the daily requirement for fortified vitamins and microelements. It has been established that the terms of sale of the "Protein" bread are 48 hours. The sales terms of "Carrot" and "Beet" bread are 72 hours, the decrease in the degree of staling of the bread is due to the use of vegetable powders (carriers of pectin), which is confirmed by an increase in the hydrophilic properties of the crumb of bread. The established patterns are important for scientists that they are working on the creation of gluten-free bread for dietary nutrition with improved quality indicators during storage, which is one of the priority and urgent tasks of the food industr

Emergence from protracted unconsciousness due to severe diffuse axonal brain injury: clinical observation and literature review

The paper gives data available in the literature on the variants of unconsciousness, bases of their development, and modes of correction. The authors analyze their observation of consciousness recovery after protracted unconsciousness (for about 6 months) during neuromodulation therapy and repetitive transcranial magnetic stimulation (rTMS) in a patient with severe traumatic and, probably, concominant hypoxic brain injury. Over time (within 2 years), they traced neurological and psychic changes, evaluated structural damages by Tl-, T2-weighted, FLAIR, and DTI magnetic resonance imaging, by constructing corticospinal tracts, and cerebral blood flow (computed tomography perfusion), and plasma catecholamines (epinephrine, norepinephrine, and dopamine). The case in question is clinical, instrumental, and laboratory evidence for the efficiency of use of not only direct stimulants of dopaminergic transmission, but also drugs with indirect dopaminergic activity, as well as rTMS for emergence from protracted akinetic mutism in the presence of akinetic-rigid syndrome