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In the processing of tomatoes into juice and subsequently into puree, the key elements of the production technology are the heat treatment processes of the crushed tomato pulp and, in the production of puree, the way the tomato juice is concentrated, which can significantly affect the nitric quality of the final product. The aim of the work was to evaluate the dynamics of changes in carotenoid and polyphenol content occurring during processing of tomatoes into tomato puree by traditional and vacuum technology. The varieties used in the work for industrial processing were Uno Rosso F1, Pavlina, Mobil, Zomok and Denar. The tomatoes were sorted, washed and crushed after harvesting. The resulting pulp was heated at 93 ± 1 °C for 3 minutes and then passivated. Traditional concentrating was carried out by boiling at 95 °C until a soluble solids content of 29 °Brix was reached, while vacuum concentrating was carried out at 70 °C until a soluble solids content of 29 °Brix was reached. Total carotenoid content was determined according to the methodology of Hegedűs et al. (2016). Extraction of carotene from the homogenized samples was performed with acetone. The acetone extract obtained was repeatedly shaken with petroleum ether and the layers were dispersed with distilled water. The carotenesaturated phase was then dried over anhydrous sodium sulphate, transferred quantitatively to a volumetric flask and made up to the specified volume with 25 mL of petroleum ether. The absorbance of the samples was measured spectrophotometrically on a JENWAY spectrophotometer (6405 UV/VIS) at a wavelength of 450 nm. Determination of total polyphenols was carried out by the Folin-Ciocalteau method. The method is based on the reaction of Folin-Ciocalteau reagent with the polyphenols present in the sample analyzed to form a blue colored product. Sample preparation for polyphenol analysis consisted of homogenization and extraction in 80% ethanol. The polyphenol content was measured spectrophotometrically at 765 nm using a Jenway spectrophotometer (6405 UV/VIS). The total polyphenol content was calculated from the gallic acid calibration curve (GAE) at a concentration of 50 - 800 mg/L. Tukey's HSD multiple comparison test at P < 0.05 was used to assess statistically significant differences between variants. By processing tomato fruits into tomato juice, we found that the carotenoid and polyphenol content decreased statistically significantly (P < 0.05) after processing the fruits into tomato juice. A further decrease in the content of the evaluated parameters continued during the production of tomato puree by traditional thickening technology, while concentrating in vacuum had a demonstrably positive effect on the evaluated parameters and ultimately resulted in a renewed increase in the carotenoid and polyphenol content. In the evaluation of the dynamics of changes in carotenoids, we found an average decrease of 8.28% after processing the fruits into tomato juice, the concentrating of tomato juice on the traditional technology meant a further decrease of 28.88% in the content of total carotenoids compared to the fruits, but after using the vacuum concentrating technology, we found an increase of 9.97% in the content of total carotenoids compared to tomato juice, and the content of carotenoids was almost at the original value of the fresh fruits. By Tukey's test, we found a statistically significant (P < 0.05) effect of tomato processing method on the content of total carotenoids. By monitoring the polyphenol content, we found that polyphenols are more vulnerable than carotenoids. In the stage of concentrating tomato juice to puree by traditional technology, the polyphenol content decreased by an average of 27.71% compared to fresh fruits, while concentrating by vacuum technology recorded a re-increase in polyphenol content by an average of 23.84% compared to juice, to a content almost identical to that of the fresh fruits. When processing tomato fruit into tomato puree, based on the results of our work, we can clearly recommend producers to prefer processing juice into puree by vacuum technology over the classical technology of thickening under oxygen. After vacuum thickening of the puree, there are ultimately only minimal changes in the content of nutritionally significant components compared with fresh raw material. [ABSTRACT FROM AUTHOR]

Tomatoes are the most commonly preserved vegetables in the world. Traditional tomato products are tomato juice, puree or ketchup but demand for dried tomatoes is increasing at the market. Drying is one of the oldest methods of preservation and often accompanies the degradation of nutritionally important ingredients. In order to protect nutrients from excessive oxidation during drying, the right choice of the drying temperature and the treatment of the raw material prior to drying are important elements of the manufacturing process. In our work we investigated the impact of various ways of antioxidant treatment of the raw material before drying on the stability of total carotenoids, polyphenols and antioxidant activity of the product. We used Uno Rosso F1 cultivar of tomatoes, dried by air at 70 °C, and the fruits were cut into slices of 3 mm thickness. To increase the stability of phytonutrients, we used the slice treatment prior to drying with 1% potassium bisulphite, ascorbic acid, citric and acetic acid and 5% sucrose and sodium chloride solutions. We found that the 1% solution of ascorbic acid was the most effective in protecting of total carotenoids and polyphenols. In the protection of total polyphenols, acetic acid and potassium bisulphite solutions were equally effective. The most significant increase in antioxidant activity was found to be ascorbic acid solution. [ABSTRACT FROM AUTHOR]

Carrot ( Daucus carota L.) belongs to the most common type of vegetable because of its consumption, versatile usage in the canning industry and because of its beneficial effects on the health of consumers. It is valuable mainly because of the high content of β-carotene, B vitamins, vitamin C, carbohydrates and minerals. The aim of this work was to compare the quality of carrot juice from different varieties of carrots regarding the content of total carotenoids and polyphenols and also to assess the dynamics of their changes evaluated under the influence of the pasteurization (85 °C). There were selected varieties of carrot such as Baltimore F1, Exhibition F1, Kamaran F1, Napoli F1, Belgrado F1, Komarno F1, Nantes, Rubina and Nandrin F1. The highest content of carotenoids, assessed by the spectrophotometry, was determined in variety Kamaran F1 (213.66 mg 100 g−1 dry matter) and the lowest in Belgrado F1 (146.80 mg 100 g−1 dry matter). After the pasteurization, the content of carotenoid decreased and ranged from 128.04 mg 100 g−1 dry matter in variety Napoli F1 to 142.55 mg 100 g−1 in Kamaran F1. The highest content of polyphenol determined by the Folin Ciocalteu method was found in fresh juice of Rubina (922.80 mg GAE 100 g−1 dry matter) and the lowest in the variety Nantes (535.75 mg GAE 100 g−1 dry matter). After the pasteurization, the content of the monitored components was found to be 450.34 mg GAE 100 g−1 dry matter in Napoli F1 to 751.95 mg GAE 100 g−1 dry matter in Komarno F1 variety. [ABSTRACT FROM AUTHOR]

Due to the content of biologically active substances, sea buckthorn (Hippophae rhamnoides L.) has become the object of great interest of both, experts and the general public. It is appreciated particularly for the high content of vitamins and other biologically active substances, not only in berries but also in leaves and bark. The aim of the study was to evaluate the nutritional quality of sea buckthorn juice prepared from different varieties of sea buckthorn based on the content of total carotenoids, polyphenols and antioxidant activity. In this study we used varieties Hergo, Tytti, Vitaminaja, Raisa, Askola, Dorana, Slovan, Leikora, Bojan, Terhi and Masličnaja. Content of different components was quantified using spectrophotometry. The total carotenoids content expressed as β-carotene content in juice ranged from 50.63 mg.100 g-1 DM to 93.63 mg.100 g-1 DM, the highest content was in variety Askola and the lowest one in Terhi. Total polyphenols content determined by Folin-Ciocalteu method ranged from 13.03 mg GAE. dm-3 DM to 25.35 mg GAE. dm-3 DM. The highest content was identified in juice of variety Dorana and the lowest one in Raisa. The antioxidant activity quantified by the FOMO method ranges from 45.11 g AA. dm-3 DM to 108.77 g AA. dm-3 DM. The highest antioxidant activity was determined in juice of Dorana and the lowest in variety Bojan. [ABSTRACT FROM AUTHOR]

Most of the global production of tomatoes is used for tomato products. The fruits to be processed are evaluated on the basis of important technological quality parameters, such as the content of dry mat ter and organic acids. Recent ly, among important quali tat ive characteristics of fruits has been included colorant content, especially lycopene. Aim of this study was to evaluate the qual ity of selected tomato varieties for industrial processing. Tested were varieties Uno Rosso, San Marzano 4, Brixol, St rombol ino, UG. 8168, Diana and Nemarock cult ivated in very hot and dry agro-climatic region. The dry matter content was determined by the gravimet ric method, the content of organic acid by titration and the content of colorants spectrophotometrically. The dry matter content of the samples ranged from 4.65% (Nemarock) to 5.93% (San Marzano 4). Content of organic acids ranged from 0.33% (Nemarock) to 0.59% (St rombolino), content of carotenoids in tomato samples ranged from 111.288 mg.100 g-1 DM (Nemarock) to 198.365 mg.100 g-1 DM (San Marzano 4). Lycopene was present in the amount of 99.438 mg.100 g-1 DM (Nemarock) to 192.687 mg.100 g-1 DM (San Marzano 4). In terms of t reatment the best properties showed San Marzano 4, which is characterized by high dry mat ter content, low organic acids and high content of colorants. [ABSTRACT FROM AUTHOR]