Search Results (7)

Flavor is the most important feature consumers use to examine fruit ripeness, and it also has an important influence on taste sensation. Nowadays, more and more consumers pay much attention not only to the appearance but also to the fruit’s aroma. Exploiting the potential of headspace solid-phase microextraction (HS-SPME) combined with sensitive two-dimensional gas chromatography and the time-of-flight mass spectrometry (GC/GC-ToF-MS) method within 30 old/traditional cultivars of apples (Malus domestica Borkh) coming from the same germplasm and 7 modern/commercial cultivars, 119 volatile organic compounds (VOCs) were identified. The largest group was esters (53), followed by alcohols (20), aldehydes (17), ketones (10), and acids (10). The richest volatile profile was ‘Grochówka’, with 61 VOCs present. The results revealed a visible difference based on VOC levels and profiles between the different apple cultivars, as well as visible similarities within the same cultivar coming from different farms. Based on a PCA, the commercial cultivars were separated into 7 clusters, including (1) ‘Gala’, (2) ‘Melrose’, (3) ‘Red Prince’, (4) ‘Lobo’, (5) ‘Ligol’, and (6) ‘Szampion’. The results of this study indicate that the profile of volatile compounds may be a useful tool for distinguishing between commercial and old apple cultivars, as well as for the varietal classification of apples from different locations. The developed method can also be used to identify other fruit varieties and origins based on their VOC composition. This may prove to be particularly valuable in the case of establishing a Protected Designation of Origin or Protected Geographical Indication. Full article

The conducted experiment evaluated the effects of three fungi—Trichoderma atroviride (Ta), Trichoderma harzianum (Th) and Phytium oligandrum (Po)—on the growth of maidens of two apple cultivars, ‘Szampion’ and ‘Topaz’, budded on two rootstocks, M.9 and M.26, in the nursery. The evaluation was based on the number of maidens obtained and their height, trunk diameter and number and length of lateral shoots, as well as the fresh weight of the leaves and the whole maiden. For the weaker-growing maidens of the ‘Topaz’ cultivar, the activity of the photosynthetic apparatus was additionally measured depending on the rootstock and fungal treatments. The number of maidens obtained improved significantly when Th (8.3–9.0%) and Po (8.4–12.8%) were applied, depending on the rootstock and cultivar used. With the best treatment with the Po fungus, on average, for the two cultivars, maiden apple trees budded on the M.9 dwarf rootstock were characterized by a significantly better height of 6% and trunk diameter of 13% compared to the control. In contrast, trees grown on the M.26 rootstock did not have significantly increased growth after the same treatments, with the exception of the Po fungus, which improved the stem diameter by an average of 10%. The use of fungi stimulated an increase in the number and length of the lateral shoots of maidens of the more easily branching ‘Szampion’ apple tree cultivar. Based on the fluorescence parameters obtained, it can be assumed that the ‘Topaz’ cultivar on the M.26 rootstock is less susceptible to stress conditions, especially those related to high temperatures and drought. All fungi used had a positive effect on the activity of the photosynthetic apparatus. Significantly worse values of the fluorescence parameters were obtained for the control combination compared to the fungal treatments. Full article

Calcium is one of the most poorly reutilized nutrients. Its deficiencies cause various physiological disturbances and, consequently, reduce the quantity and quality of yields. Reduced content of Ca²⁺ ions in cells leads to development of, e.g., bitter pit in apples. Efficient and instantaneous mitigation of Ca²⁺ deficiencies is provided by foliar feeding. There are no detailed data on the effect of foliar feeding with various calcium forms on the cell structure or on the microanalysis and mapping of this element in apple fruit cells. Therefore, we carried out comparative studies of the ultrastructure of epidermis and hypodermis cells, to assess the content and distribution of calcium in the cell wall, cytoplasmic membrane, cytoplasm, and precipitates of Malus domestica Borkh. ‘Szampion’ fruit exposed to four Ca treatments, including the control with no additional Ca supplementation (I) and foliar applications of Ca(NO₃)₂ (II), CaCl₂ (III), and Ca chelated with EDTA (IV). Light and transmission electron microscopy and an X-ray microanalyzer were used and showed a beneficial effect of calcium preparations on the ultrastructure of fruit epidermis and hypodermis cells, manifested in the presence of a normally developed cell wall with a regular middle lamella, preserved continuity of cytoplasmic membranes, and stabilized cell structure. In the selected elements of apical epidermis cells, the highest level of Ca²⁺ ions was detected in the middle lamella, cell wall, plasmalemma, and cytoplasm. The highest increase in the Ca²⁺ content in these cell constituents was recorded in treatment IV, whereas the lowest value of the parameters was noted in variant III. Full article

Volatile profile of spirits is the most important factor, because it can contribute to pleasant flavor. The aim of the study was to determine the impact of dessert apple cultivar used for fermentation on the concentration of volatile compounds in apple spirits. SPME-GC-MS (solid-phase microextraction- gas chromatography- mass spectrometry) method enables the detection of 69 substances and GC-FID (gas chromatography - flame ionization detector) 31 compounds. Characteristic volatiles for brandies obtained from Topaz were limonene, myrcene, methyl valerate and 1,1-diethoxy-propane, from Rubin—β-citronellol and isopropyl acetate, Elise—limonene, myrcene benzyl acetate and isopropyl acetate, Szampion—β-citronellol, Idared—1,1-diethoxy-propane and Jonagored—ethyl trans-4-decanoate. Of the ten analyzed apple spirits, those obtained from Topaz, Rubin and Elise cultivars demonstrated the most diverse profile of volatile compounds. Moreover, their oenological parameters that are the most important in the production of alcoholic beverages were the most favorable. On the other hand, the content of sugars was relatively low in Elise must, while it was highest in Topaz must, which later on translated into differences in alcohol content. Brandies obtained from Gloster contained the smallest concentrations of esters and terpenes. Results of the sensory analysis showed that highest rated brandies were obtained from Topaz, Rubin, Elise and Florina. Full article

Postharvest treatment by 1-methylcyclopropene (1-MCP) for ‘Szampion’ cultivar apples inhibits ripening of climacteric fruit by blocking ethylene receptors, preventing ethylene from binding and eliciting its action. It is also possible to apply 1-MCP preharvest, which so far has not been studied for the ‘Szampion’ cultivar. The aim of this study was to assess the effects of preharvest 1-MCP treatment on the fruit quality parameters of cold-stored ‘Szampion’ cultivar apples in a Polish experiment. Two identical groups of apple trees (6 years, experimental orchard in Warsaw) were included, to obtain studied apples (preharvest 1-MCP treatment with Harvista^TM, 150 g/ha, 7 days before the optimum harvesting window, OHW) and control apples (1-MCP not applied). Apples for the studied group were harvested twice—on 28 September (OHW) and 24 October (delayed harvesting)—and for control group once—on 28 September, as before 24 October the majority of apples fell from trees. Afterwards, apples were stored in an Ultra Low Oxygen chamber (1.2% CO₂, 1.2% O₂). Apples were assessed in the preharvest period (weekly, six measurements for the studied group, and five measurements for the control group) and postharvest period (monthly, three measurements separately for each harvest time for the studied group and control group). The following parameters were assessed: internal ethylene content (IEC), firmness, total soluble solids (TSS) content, starch index, Streif index, titratable acidity (TA), and color for blush. For the preharvest period, statistically significant differences between the studied group and the control group were observed for IEC, the a* coordinate of color (p < 0.05; for apples treated with 1-MCP lower results), firmness, Streif index, TA (p < 0.05; higher results), and starch index (p < 0.05; no defined trend). For the postharvest period, statistically significant differences between the studied group and the control group were observed for apples harvested in the OHW for firmness (p < 0.05; for apples treated with 1-MCP higher results) and IEC (p < 0.05; no defined trend), while for delayed harvesting the differences were only minor. It may be concluded, that preharvest 1-MCP application makes it possible not only to obtain better results for ‘Szampion’ cultivar apples’ quality parameters, but also allows delayed harvesting without deterioration in quality. Full article

The paper presents the possibility of applying a twin-screw press for juice extraction from apples with different textural properties. The research was carried out with six different varieties; namely, Granny Smith, Modi, Ligol, Lobo, Boscop and Szampion. During the experiment, the following properties were measured: texture properties, pressing yield and polyphenolic content; and ascorbic acid content and antioxidant activity both in raw apples and apple juice. Based on the analysis, three hardness levels of apples can be distinguished, impacting the course of juice pressing in a twin-screw press (low hardness below 30 N, medium hardness 30–50 N and high hardness 50 N). The study showed that only high hardness apples are suitable for pressing on a twin-screw press. The mechanism by which texture properties influence the juice pressing process in the studied press was explained. It was further demonstrated that the hardness of apples has a positive impact on the degree of extraction of polyphenols and ascorbic acid into apple juice. This is caused by the different fracture patterns of tissues with different mechanical properties. High hardness apples (Granny Smith and Modi) were characterized by a considerably greater degree of bioactive substance extraction into juice than medium hardness apples. Full article

Determination of the optimum harvest window plays a key role in the agro-food chain as the quality of fruit depends on the right harvesting time and appropriate storage conditions during the postharvest period. Usually, indices based on destructive measurements are used for this purpose, like the De Jager Index (PFW-1), FARS index and the most popular Streif Index. In this study, we proposed a biospeckle method for the evaluation of the optimum harvest window (OHW) of the “Ligol” and “Szampion” apple cultivars. The experiment involved eight different maturity stages, of which four were followed by long cold storage and shelf life to assist the determination of the optimum harvest window. The biospeckle activity was studied in relation to standard quality attributes (firmness, acidity, starch, soluble solids content, Streif Index) and physiological parameters (respiration and ethylene emission) of both apple cultivars. Changes of biospeckle activity (BA) over time showed moderate relationships with biochemical changes during apple maturation and ripening. The harvest date suggested by the Streif Index and postharvest quality indicators matched with characteristic decrease in BA. The ability of biospeckle method to characterize the biological state of apples was confirmed by significant correlations of BA with firmness, starch index, total soluble solids and Streif Index, as well as good match with changes in carbon dioxide and ethylene emission. However, it should be noted that correlations between variables changing over time are not as meaningful as independent observations. Also, it is a well-known property of the Pearson’s correlation that its value is highly susceptible to outlier data. Due to its non-selective nature the BA reflected only the current biological state of the fruit and could be affected by many other factors. The investigations showed that the optimum harvest window for apples was indicated by the characteristic drop of BA during pre-harvest development. Despite this, at the current state of development the BA method cannot be used as an indicator alone. Due to rather poor results for prediction in OHW the BA measurements should be supported by other destructive methods to compensate its low selectivity. Full article