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Traditional winter pruning in dormancy (BBCH-00) as control (C) and three late pruning treatments, LP1 (wool stage—BBCH-05), LP2 (two leaves folded—BBCH-12), and LP3 (four leaves folded—BBCH-14), were applied on Kékfrankos grapevines. The evolution of the phenological growth stages, grape juice, wine analytical parameters, and phenolic composition were evaluated. The quantitative aspects of the grape berry, bunch, yield, and cane were also assessed. Our goal was to reach a decrease in sugar content and an increase in acidity. Delaying or postponing the phenological phases to bring technological and phenolic ripening closer together was also one of our objectives. These were accomplished, but the negative aspects of late pruning, which resulted in a reduction in the diameter and weight of the canes, should also be taken into account. We also found that, the later the late pruning, the more the yield was reduced. By postponing pruning, the phenological phases were also extended. [ABSTRACT FROM AUTHOR]

Polyphenols, fatty acids, and mineral composition were studied in eight Persian walnut (Juglans regia L.) samples: 'Milotai 10' (M10) and 'Alsószentiváni 117' (A117) Hungarian varieties derived from two Hungarian growing areas (Pálháza—P and Berzék—B), 'Chernivets'ky 1' from Ukraine, and 'Chandler' from the United States of America, Chile, and Brazil purchased on the Hungarian consumer market. The aim was to reveal which walnut variety is the most suitable for consumption from a nutritive point of view. In comparison, both Hungarian varieties grown in Hungarian climatic conditions had on average approximately 33% more polyphenols, approximately 22% more SFAs (saturated fatty acids), and approximately 27% more MUFAs (monounsaturated fatty acids). Regarding the minerals, calcium, magnesium, phosphorus, and sodium were present in higher concentrations in both Hungarian varieties. Among the Hungarian-bred varieties, M10 mainly reached a higher compounds content, but the effects of the fruit site conditions were not clearly detected. Other varieties contained mainly potassium, copper, and zinc, such as 'Chandler' harvested from Chile. 'Chernivets'ky 1', harvested from Ukraine, had outstanding cinnamic acid and linoleic acid contents compared to the other examined varieties. All 'Chandler' samples (mainly the American) contained 11% more PUFAs compared to the samples derived from Hungary. [ABSTRACT FROM AUTHOR]

A relatively novel approach for easy and quick determination of rutin in buckwheat grain is suggested. The rutin content of the grain in seven common buckwheat (Fagopyrum esculentum) and six Tartary buckwheat (Fagopyrum tataricum) varieties was investigated by means of UV photoacoustic spectroscopy and HPLC as reference method. The lowest content was found in ‘Botan’ and ‘Bamby’ varieties, while the highest values were obtained in the variety ‘Emka’. Rutin content in grain of all Tartary buckwheat varieties was two orders of magnitude higher than in the other varieties. Rutin content in F. esculentum ranges between 9 and 36 mg/100 g dry weight as compared to 921 to 2 132 mg/100 g dry weight in F. tataricum. The UV photoacoustic spectroscopy data show rather good correlations of R2=0.977 and R2=0.980 with values obtained by HPLC data for all measured samples. Therefore, UV photoacoustic spectroscopy can be a cheap and quick method for determining rutin content in buckwheat grain.

Sea Buckthorn (SB) juice is rich in biologically active compounds. It has considerable health benefits; thus, it can serve as functional food ingredient. The aim of this study was to determine and compare the total content of polyphenols, antioxidant capacity (FRAP), soluble solid content, pH value, β-carotene content and colour parameters (L*, a*, b*) in berry juice of cultivar 'Leikora' Sea Buckthorn (SB) (Hippophae rhamnoides L.). The treatment was made as control sample of Sea Buckthorn juice (C), and Sea Buckthorn juice with 0.5 % (P0.5); 1 % (P1); 2 % (P2) dried pomace of Sea Buckthorn. The samples were stored at room temperature for physicochemical analysis at interval of 2 months for a total period of 14 months. According to our results, the β-carotene ( C to P2 was 3.71, 4.82, 5.49 and 6.52 mg 100 mL-1 ) as well as the antioxidant capacity of the samples increased with the growth of the pomace content. During storage, degradation occurred in the polyphenol content and antioxidant capacity, but the β-carotene content increased. The increase of the β-carotene content was 94.6 % (C) and 32.7 % (P0.5). The smaller reduction in antioxidant compounds was the higher the sample of pomace content is. The FRAP and total polyphenol values measured during storage confirm that the pomace has antioxidant effect. There is a close correlation between the two parameters, including a positive correlation (r = 0.8614), which indicates that a significant part of the antioxidant capacity of buckthorn is due to the presence of different polyphenols. [ABSTRACT FROM AUTHOR]

Background. Photoacoustic spectroscopy (PAS) is a tool for the rapid and non-destructive identification of materials even without contact. In recent years, there have been several works concerning the applicability of PAS in food analytical measurements. The intention of this work is to identify whether there is a correlation between total carotenoid and the β-carotene content of pumpkin and squash measured by high-performance liquid chromatography (HPLC), spectrophotometry (SP) and PAS. Material and methods. 'Crown prince F1', 'Veenas F1', 'Atlas F1' and 'Apollo F1' (SAKATA) were used as experimental materials. The samples were measured in a fresh state and in a lyophilised condition with HPLC, SP and PAS. Results. The results of SP show that total carotene content varies according to the species and variety. Lyophilisation resulted in lower, although varying carotene content compared to the raw form. Typical PA spectra of pumpkins were determined (300-550 nm), normalized to the carbon black powder. At 17 Hz the amplitude and carotene content shows direct proportionality in the range investigated. Photoacoustic (PA) signal and carotenoid content of pumpkin samples gave a linear correlation (R2 = 0.9821). Conclusion. The measurement of PA spectra gives reliable information about the total carotene content of pumpkin and squash samples. These findings may allow the use of PAS as a fast tool for the carotenoid determination in squashes and give the possibility of instead for the results to be used for the evaluation of squash varieties currently used for industrial processing in functional food development. [ABSTRACT FROM AUTHOR]

Minor crops are gaining new interest due to the high content of bioactive compounds available in their grain and the consequent opportunity to be employed as ingredients for the production of healthy foodstuff. Tartary buckwheat (Fagopyrum tataricum Gaertn.) grain is rich in flavonoids, the most important being represented by rutin, a compound possessing a high health value. When processing bakery products added with Tartary buckwheat whole flour, the key point is to prevent rutin from being hydrolysed to quercetin. In this view, a combination of heat treatment and controlled humidity level was applied for different lengths of time, in the attempt to deactivate the enzymes catalysing the reaction. Tartary buckwheat grain contains other polyphenols also capable to confer health properties. This class of compounds has been associated with the prevention of cardiovascular diseases, cancers, neurodegenerative diseases, diabetes, and osteoporosis. In this study it was observed how the physical treatments meant to preserve rutin would influence the overall content of polyphenols in Tartary buckwheat whole flour and dough. [ABSTRACT FROM AUTHOR]

Sour cherry juices made from two sour cherry cultivars (Érdi bőtermő and Kántorjánosi 3) were investigated to determine their total anthocyanin content and half-life of anthocyanins during heat treatment at different temperatures (70, 80 and 90 °C) for 4 h. Before the heat treatment, Érdi bőtermő juice had higher anthocyanin concentration (812 mg/L) than Kántorjánosi 3 juice (513 mg/L). The greatest heat sensitivity of anthocyanins was measured at 90 °C, while the treatments at 80 and 70 °C caused lower thermal degradation. The loss of anthocyanins in Érdi bőtermő juice aft er treatment was 38, 29 and 18%, respectively, while in Kántorjánosi 3 juice losses of 46, 29 and 19% were observed, respectively. At 90 °C sour cherry Érdi bőtermő juice had higher half-life (t1/2) of anthocyanins, while the Kántorjánosi 3 juice had higher t1/2 values at 70 °C. Cyanidin-3-glucosyl-rutinoside was present in higher concentrations in both cultivars (Érdi bőtermő: 348 and Kántorjánosi 3: 200 mg/L) than cyanidin-3-rutinoside (177 and 121 mg/L) before treatment. However, during the experiment, cyanidin-3-rutinoside was proved to be more resistant to heat. Comparing the two varieties, both investigated pigment compounds were more stable in Kántorjánosi 3 than in Érdi bőtermő. Degradation rate of anthocyanins was cultivar-dependent characteristic, which should be taken into account in the food production. [ABSTRACT FROM AUTHOR]

Photoacoustic spectroscopy (PAS) and reflectance colorimetry are suggested as new tools for the analysis of total carotenoids in lyophilized apricot powders. The data obtained by these two techniques from seven apricot cultivars were compared to those acquired by spectrophotometry and high-performance liquid chromatography (HPLC). Best correlations were found between the total carotenoid (TC) content (obtained by VIS spectrophotometry: 1.2-3.4 mg per 100 g of fresh mass) and colorimetric index a* (a* represents the redness of the investigated sample), as well as either argon-ion laser- or xenon-lamp--based PAS. In all three cases linear correlations were comparable. However, according to the sensitivity and precision data, expressed via limit of detection (LOD) and measurement repeatability, the Xe-lamp-based PAS is a preferred approach, followed by colorimetric index a* and Ar-ion laser PAS. Both PAS methods exhibit practically the same Pearson's correlation coefficient (R=0.987 and R=0.991) values. Nevertheless, residual sum of squares (RSS) and residual standard deviation of the linear regression (sy/x) differ markedly. For Xe-lamp-based PAS these parameters were much lower than in the case of Ar-ion laser PAS. Likewise, analysis imprecision amounted to relative standard deviation (RSD) of 1-3 % for Xe-lamp PAS and 2-6 % for Ar-ion laser PAS. On the other hand, as expected, the calibration sensitivity achieved for the PAS signal induced by an Ar-ion laser at 481 run was substantially higher than that of a Xe-lamp at 470 nm. Nevertheless, according to much lower sy/x/ the corresponding LOD for Xe-lamp PAS was still two times lower than that of Ar-ion-based laser PAS (0.59 vs. 1.10 mg per 100 g). Unlike this, Ar-ion laser PAS showed more favourable instrumental precision and standard error of the weighed mean when compared to the Xe-lamp PAS (0.1-0.6 and 0.1-0.3 % vs. 0.5-8.0 and 0.4-1.7 %, respectively). As far as colorimetric indices are concerned, only a* proved to be analytically useful; excellent R but rather modest RSS and Sy/x resulted in LOD value of 0.70 mg per 100 g and acceptable analysis imprecision of up to 3 %. The outcome of this research provides sufficient amount of evidence that analytical methods such as reflectance colorimetry and PAS without the use of any chemicals are feasible for reliable quantification of total carotenoids in freeze-dried apricot homogenates. [ABSTRACT FROM AUTHOR]

Thanks to the high rutin content of its grain and whole flour, tartary buckwheat can be proposed as an ingredient of new food preparations containing effective amounts of this bioactive compound credited to exert a growing multiplicity of health beneficial properties. In this respect, most dietary supplement preparations, containing around 50 mg of rutin, are suggested as the daily preventive dose. Considering that the content of rutin of tartary buckwheat whole flour usually ranges between 1000 up to 2000 mg/100 g dry weight, the introduction of a low percentage of this ingredient in the original recipe would allow to reach such amount in a food largely consumed like bread. Preliminary result would indicate that, in the preparation of a typical Tuscany bread, a certain amount (up to 20%) of wheat flour can be replaced by a mixture of common and tartary buckwheat whole flour so to allegedly secure an intake of 50 mg of rutin through the average daily consumption of bread (about 200 g) in addition to an appreciable content of beneficial buckwheat protein and amylase resistant starch. However, efforts are to be dedicated to identify the most suited wheat flour in order not to impair texture, taste and acceptability of the bread so amended. In addition most of the rutin was not recovered in the final products, either degraded to quercetin or lost during preparation and baking processes. Research are underway to verify the extent of rutin degradation to quercetin by the hydrolyzing enzymes, known to be present in tartary buckwheat grain, during the phase of dough formation and successive leavening and to workout processing conditions apt to control such a phenomenon. [ABSTRACT FROM AUTHOR]