Kale (Brassica oleracea L. var. acephala) is a cold-tolerant leafy vegetable whose metabolic plasticity under frost stress remains underexplored. In this study, leaf tissues from 26 kale accessions grown under open-field conditions were metabolically profiled, focusing on soluble sugars, glucosinolates, and photosynthetic pigments before and after exposure to short-term frost. Frost stress induced significant quantitative and compositional shifts in sugar profiles, notably an accumulation of sucrose, suggesting its role as a key osmoprotectant. Among the twelve glucosinolates identified, indolic compounds dominated the unfrosted profile (67.4 %) but declined post-frost (51.6 %), coinciding with a marked increase in aliphatic glucosinolates (from 20.7 % to 38.6 %). Chlorophyll and carotenoid contents declined in most accessions following frost exposure. Notably, the metabolic profile of Accession_4 indicates a potentially resilient phenotype, characterised by limited pigment degradation and a shift toward aliphatic glucosinolates. This may reflect a stress-adaptation strategy and could be explored as a candidate for breeding or metabolotype selection approaches.

Hemp is becoming increasingly popular, and many new varieties are coming onto the market to meet the requirements of different industries. In this study, the seed and stem yield, seed nutritional properties and the biochemical characteristics of the inflorescences of seven European varieties (Fedora 17, Futura 75, KC Dora, Monoica, Santhica 27, Tiborszallasi, USO 31) were investigated in a 3-year field trial. Futura 75 and Tiborszallasi stand out as varieties with the highest potential in the conditions of the experiment (humid continental climate with oceanic influences, heavy soil). Futura 75 achieved the highest seed yield (505 kg/ha dry matter), stem yield (8 036 kg/ha fresh matter), protein yield (140 kg/ha) and oil yield (181 kg/ha). There were no differences in protein content (average 21.0%) among varieties. The total unsaturated fatty acid content was as high as 87.6% at Tiborszallasi. The best ratio between omega-6 and omega-3 fatty acids was 3 : 1 in Tiborszallasi, which had also the highest oil content (30.2%), the highest total phenolic content (2.8 mg caffeic acid (CA)/g) and the best antioxidant potential (6.69 EC50 DPPH (2,2-diphenyl-1-picrylhydrazyl) mg/L). Most varieties had higher cannabidiol and tetrahydrocannabinol contents in the inflorescence at seed maturity (from 0.22 to 3.3 for cannabidiol (CBD) and from 0.00 to 0.32 for tetrahydrocannabinol (THC)) compared to full flowering (from 0.17 to 4.33 for CBD and from 0.00 to 0.52 for THC, on average 2.64% for CBD and 0.19% for THC), presenting an opportunity for dual-purpose use.

This study investigated the biochemical and quality changes in mechanical and hand-harvested olive fruit of the cultivars 'Istrska belica' and 'Leccino' during storage. It investigated changes in phenolic compounds and fatty acid composition, analysed using HPLC and GC methods, to understand how different harvesting methods, affect olive quality during storage. The results showed that harvesting methods had different effect on fruit quality, which became more pronounced during storage. Hand-harvested olives maintained better fruit integrity, delaying slower degradation, whereas mechanically harvested olives showed greater damage at harvest, leading to accelerated biochemical changes. At harvest, 'Istrska belica' olives responded immediately to mechanical damage by accumulating phenolic compounds such as tyrosol (increased by 43 % from 18.3 to 26.1 mg/kg FW), verbascoside (33 % from 792 to 1049 mg/kg FW), hydroxytyrosol (55 % from 27.1 to 42.0 mg/kg FW), compared to manually harvested fruits, together with an increase in certain fatty acid compositions (palmitic (67 % from 11.2 to 18.7 mg/100 g FW), palmitoleic (96 % from 0.5 to 1.0 mg/100 g FW), stearic (49 % from 4.2 to 6.3 mg/100 g FW), and linoleic acids (44 % from 6.5 to 9.3 mg/100 g FW), probably due to membrane damage. In contrast, 'Leccino' fruits showed minimal metabolic differences compared between harvesting methods. During storage, the phenolic content of mechanically harvested 'Leccino' olives initially increased due to stress-induced metabolic activity, but significantly decreased after 16 days, indicating fruit deterioration. Meanwhile, hand-harvested 'Leccino' olives maintained stable phenolic and fatty acid profiles. During storage, mechanical harvesting of 'Istrska belica' caused the degradation of oleuropein (for 21.9 %) and other phenolic compounds, while oleuropein degradation products such as tyrosol, elenolic acid, demethyloleuropein increased, whereas hand-harvested fruit maintained stable content of six phenolic compounds and four fatty acids.

Soil salinization is a major constraint in horticulture, reducing yield and resource-use efficiency in high-value crops. While salinity generally inhibits plant growth, it can enhance the accumulation of bioactive compounds in medicinal and aromatic species. This study aimed to evaluate the effects of salinity and amino acid–based biostimulants on yield and phytochemical composition of hydroponically grown flat-leaf parsley (Petroselinum crispum var. neapolitanum). We hypothesized that salinity would reduce biomass while increasing phenolic and volatile compounds, and that biostimulants would mitigate yield loss under stress. Salinity (40 mM NaCl) reduced yield nearly fivefold compared to control plants. Biostimulant application partially alleviated this effect, increasing yield by 73.3 and 54.6

Drip loss is the liquid released from frozen strawberries during defrosting. High levels of drip loss make strawberries unsuitable for many applications that require whole fruit. This study is aimed at investigating the relationship between strawberry drip loss and the colour stability of nectars produced from these strawberries. Both solid (remainder after drip removal during defrosting) and liquid fractions (drip loss) were analysed by HPLC for anthocyanin, sugar and acid concentration, as well as total soluble solids and titratable acidity, to compare differences between the fractions. The results showed a strong correlation between strawberry drip loss and the colour stability of the resulting nectars. Strawberries with high levels of drip loss produced nectars with more stable colour. Determining the percentage of drip loss provides a quick and low-cost method for industrial nectar producers to select strawberries suitable for the production of colour-stable nectars. Furthermore, it was demonstrated for the first time that higher levels of solid content, achieved by separating the drip loss of defrosted strawberries before processing into puree, lead to nectars with higher initial consumer acceptance factor (AF) and a higher AF after 12 weeks. As a result, these nectars had a significantly better colour stability.

The presented study aimed to fully characterise berry powders derived from raspberry, blackberry and strawberry (RB, BB, SB) as well as raspberry and blackberry seed powders (RBS, BBS) in terms of proximate composition, the individual profile of minerals, sugars, organic and fatty acids, and phenolic and volatile compounds. Additionally, testing of powders' colour and antioxidant activity, as well as spectroscopic analysis, were also performed. Higher total and individual sugars, organic and phenolic acids, flavonols and anthocyanins content distinguished berry powders from the seed powders. Individually, RB contained significant amounts of citric and chlorogenic acids, BB was superior in cyanidin-3-O-glucoside and quercetin-3-O-rutinoside content, while SB was characterised by high sucrose, fructose, omega-3, and mineral (Ca, Mg, Fe) content. Berry seed powders exhibited remarkable TDF content, beneficial PUFA/SFA ratio, lighter colour, higher individual flavan-3-ols quantity, TPC and DPPH activity compared to berry powders. Mentioned discrepancies between berry and berry seed powders on a compositional level were also visible on ATR-FTIR spectra across all detected regions reflecting bonds attributed to cellulose, lipids, phenols and sugars. Pleasant, predominantly green, fruity and floral aromas were associated with berry powders, whilst additional herbal notes were characteristic of berry seed powders, all derived from the alcohols, aldehydes, esters and ketones as paramount volatile compounds. All examined powders can bear a nutritional claim of "high in" fibre (20.47-65.33%) and Mg (114.52-128.70 mg/100 g), enabling the design of food products packed with nutrients and bioactives while simultaneously reducing fresh fruit and fruit-processing waste.

Our research aimed to determine how pollen donors affected fruit set, weight, and phytochemical composition of plum 'Crvena Ranka,' a key cultivar suitable for producing high-quality brandy in the Serbian market, with growing export potential. Traditional polliniser 'Dragacevka' and cultivars widespread in production, 'Cacanska Lepotica' and 'Cacanska Rodna,' free and mixed pollination were chosen as pollen sources. The highest fruit set was observed in the crossing combinations with 'Cacanska Lepotica' and 'Cacanska Rodna'. There were no significant variations in total sugar (TS) among pollen donors. Significantly higher levels of total acids (TA) and individual organic acids are recorded with a pollen mixture, resulting in a significantly lower TS/TA compared to other polliniser combinations. The highest content of phenolic groups (hydroxybenzoic and hydroxycinnamic acids, flavonols, flavones, flavanols, anthocyanins) and their sum was detected in mixed pollination. These results indicate the synergistic effect of metaxenia of different pollen sources on the overall fruit quality of the maternal cultivar. Cacanska Lepotica' and mixed pollen significantly improved fruit quality, suggesting that growing 'Crvena Ranka' with 'Cacanska Lepotica' or in a multi-varietal orchard could enhance production to obtain high-quality plum products.

This study investigates enzymatic browning in several white-and red-fleshed apple cultivars by analyzing polyphenol oxidase (PPO) and peroxidase (POX) activities, total phenolic content (TPC), anthocyanins, ascorbic acid, and color changes during air exposure. Six white-fleshed cultivars ('Topaz', 'Opal', 'Red Boskoop', 'Golden Delicious', 'Crown Prince Rudolph', 'Idared') and the red-fleshed cultivar 'Baya Marisa' were evaluated. Results revealed cultivar-specific enzymatic activity influencing browning susceptibility. 'Idared' exhibited the highest PPO activity and the strongest browning potential, while 'Baya Marisa' showed low PPO but unexpectedly high POX activity. All white-fleshed cultivars were prone to browning, as indicated by a significant increase in browning index (BI) from 0 to 480 min. In contrast, 'Baya Marisa' showed minimal color change and no significant BI variation, suggesting limited browning. However, due to high a* values, BI may not be suitable for assessing browning in red-fleshed cultivars. 'Golden Delicious' had the highest initial ascorbic acid concentration and the slowest degradation rate. 'Baya Marisa' consistently exhibited the highest TPC, attributed to elevated anthocyanin levels. These findings emphasize the importance of cultivar selection in managing browning and highlight limitations of BI as a universal indicator, particularly for red-fleshed apples.

The aim of this study was to analyse the ripening process of two European plum cultivars, 'Nada' and 'Stanley'. As the effects of climate change are becoming increasingly evident, plum producers are facing new challenges. Therefore, the study was conducted in two consecutive years (2021 and 2022) characterised by different weather conditions during the ripening of the plum fruit. The first harvest was performed when 70 % of the fruit surface was covered with cultivar characteristic colour, while the last sampling date coincided with fruit drop. In addition to the basic fruit quality parameters (fruit weight, firmness, total soluble solids), 35 primary and secondary metabolites (sugars, organic acids and phenolics) were identified and quantified by HPLC analysis. Certain trends such as the decrease in fruit firmness, the accumulation of sucrose and anthocyanins and the degradation of malate, were observed during the ripening of two cultivars studied. No clear trend was observed for hydroxycinnamic acids, flavonols, flavanols and flavanones, although the most dominant phenolic compound in all ripening stages was 3-caffeoylquinic acid. Principal component analysis showed that ripening was largely cultivar-dependent and that the behaviour of the same cultivar differed between growing seasons. It was found that heat waves in combination with drought periods accelerated the ripening process, which had a particular effect on the softening rate.

In this study, changes in visual, physical and biochemical parameters of mechanically harvested olive fruit cultivar 'Istrska belica' were evaluated during 23 days of storage under cold (C) and uncontrolled (U) conditions over two years. At harvest, the fruit of both years had a similar maturity index (0.62 and 0.76) and fruits weight (2.75 g and 2.85 g) but different firmness (5.98 N and 5.77 N) and phenolic content. In 2022, fruit at harvest were softer and had more damaged spots after mechanical harvest, which resulted on a greatest decrease in antioxidant capacity during storage (for 12 % in U and 9 % in C). Although, firmness and fruit weight decreased while the maturity index increased, the changes during storage were more evident in phenolic content, from which oleuropein decreased the most (in 2021 for 30 % in U and 18 % in C, in 2022 for 31 % in U and 15 % in C). Consequently, the content of its degradation products, including demethyloleuropein glucoside, elenolic acid, and verbascoside, increased over time under both storage conditions. On the other hand, an increase in oleuropein degradation was observed under uncontrolled storage conditions, which was also confirmed by the faster increase in the final products (elenolic acid glucoside, hydroxytyrosol glucoside and oleoside). Changes in phenolic contents, physical parameters and damage propagation were slower at the lowest storage temperature. The initial quality of the fruit, such as ripeness, firmness and damage, also had a strong influence on changes during storage. The results suggest that fruit should not be overripe before storage and should be cooled as soon as possible for the shortest time necessary to minimise oxidation and phenolic degradation.

The growing market demand for environmentally friendly products for plant nutrition has led to the development of new fertilizers, particularly liquid compost-based products such as teas, extracts, and leachates. The aim of this research was to compare the effect of chemical fertilization (CF) and its combination with liquid fertilizer based on vermicompost and beneficial microorganisms (CF + VP) on the phytochemical profile of strawberry (Senga Sengana), blackberry (& Ccaron;a & ccaron;anska Bestrna) and blueberry (Aurora). The results showed that CF + VP positively affected fruit weight (8.8 g), soluble solids (8.9 degrees Bx), total sugars (65.5 g/kg FW), and the sum of all phenolic groups (275.12 g/kg FW) in blackberry fruits. Significantly higher fruit weight (15.5 g), total sugars (62.4 g/kg FW), organic acids (9.6 g/kg FW), and flavanones (20.06 mg/100 g FW) content in strawberry fruits were confirmed in CF + VP. The same treatment exhibited the highest effectiveness in terms of organic acids (17.3 g/kg FW) and anthocyanins (153.26 g/kg FW) in blueberry. The application of CF + VP improved all components of fruit quality in the examined species compared to CF, and the positive impact was particularly pronounced in the phenolic composition of blackberries. Taking into account the stimulating effects on the sensory and nutritional value of the fruit of the studied berry species, the usa of VP as a supplement to CF can be regarded as a sustainable practice for enhancing growing technology aimed at obtaining biologically valuable fruits.

The use of photoselective nets in highbush blueberry (Vaccinium corymbosum L.) orchards could affect the light properties below the nets, along with the plants' physiological processes and the chemical composition of their leaves. In our research, we compared the effects of black, red, yellow, and white exclusion nets with full-sun conditions (control) on light quality and quantity and the performance of blueberry 'Bluecrop' leaves over two consecutive years. The light properties were found to be altered by the nets. The net photosynthesis and leaf gas exchange did not differ among the treatments in 2022. In 2023, the lowest net photosynthesis was measured in the leaves of plants under the control treatment (7.08 mu mol m_ 2 s_ 1) before harvest and under the black (3.01 mu mol m_ 2 s_ 1) and red nets (3.36 mu mol m_ 2 s_ 1) after harvest. At the same time, plants without fruit exhibited significantly lower values of carbon assimilation. The highest chlorophyll fluorescence value was measured in the plants under the red net (0.59) before harvest and under the white exclusion net (0.40) after harvest. Among the measured chloroplast pigments, zeaxanthin increased under the yellow net and the control treatment in 2022, while in 2023, it increased under the red net, white exclusion net, and control treatment before harvest. The total phenolics differed significantly among the treatments across all three sampling dates, with the highest contents measured before harvest in 2023. These promising results indicate that other blueberry cultivars and colored photoselective nets should also be examined in future experiments.

This study investigates the changes in mechanically harvested ‘Leccino’ olives stored under cold and room-temperature conditions from harvest up to 23 days of storage during two consecutive seasons. Variations in quality parameters, including maturity index, weight, firmness, and colour, were monitored throughout the storage period. In addition, the phenolic profile of the olives was analysed using HPLC, and the fatty acid composition was determined by GC–MS. These analyses enabled a comparison of changes across different storage durations, seasons, and storage conditions. Results show that fruit ripeness at harvest differed notably between the two seasons. In the second season, the olives displayed a higher maturity index, lower firmness, and lower content of certain individual phenolic compounds, indicating a more advanced stage of ripening compared to that of the previous year. These initial differences strongly influenced the subsequent development of fruit quality and biochemical characteristics during storage. Storage temperature had a significant effect on the quality parameters and metabolism. As expected, olives stored at room temperature lost their firmness and weight more quickly than those stored under cold conditions. The most abundant phenolic in olive fruit, oleuropein, degraded more rapidly at room temperature, resulting in a quicker accumulation of its derivatives. Fatty acids were more stable than phenolic compounds during storage, likely due to their lower susceptibility to enzymatic degradation and oxidative reactions under the tested conditions. While saturated fatty acids remained largely unchanged, a slight increase in unsaturated fatty acids was observed after 23 days of cold storage, possibly as a result of adaptations of the membrane to cold storage conditions.

The aim of this research was to determine the changes in fruit quality parameters, antioxidant capacity and phenolic content during natural fermentation of five olive cultivars. During processing, the fruit weight and firmness decreased and dry matter increased in all cultivars. Nine phenolic compounds were studied in detail during natural fermentation for the first time. 'Istrska belica' have the highest contents of phenolics, which require the longest processing period. Oleuropein content decreased during processing in all cultivars, resulting in fruit browning, a decrease in antioxidant capacity and an increase in other derived phenolic compounds. We found that the contents of bitter phenolic compounds stabilized a few months before the end of processing and the bitter taste in the final products did not differ between cultivars, although their content varied between cultivars. Understanding phenolic variations during the olive processing could reduce processing time and increase phenolic content in the final product.

This study investigates the effects of four preservation treatments: thermal pasteurization (TP), ohmic heating (OH), high-pressure processing (HPP), and pulsed electric fields (PEF), on the aroma and phenolic compounds of strawberry nectar, under equivalent microbial inactivation conditions (5-log reduction) on pilot-scale systems. Changes during 60 days of storage at 4 degrees C were also evaluated. HPP was the most effective method for retaining aroma compounds, with initial levels of 5.29 +/- 0.03 mg/L, closely to the untreated samples, while TP showed the lowest retention (2.94 +/- 0.13 mg/L). During storage, HPP-treated samples had a 41.6 % reduction in aroma compounds but still the highest remaining concentrations after storage compared to the other treatments. Key aroma markers, such as mesifurane, methyl and ethyl butyrate, were significantly better preserved in HPP and PEF treated samples compared to TP and OH. Phenolic content followed a similar trend: immediately after treatment HPP and PEF samples exhibited the highest total phenolic content (TPC), including anthocyanins like pelargonidin-3-glucoside, which constituted up to 81 % of total anthocyanins. Non-thermal methods (HPP and PEF) preserved phenolics better than TP, although differences between treatments were not significant after 60 days of storage. OH demonstrated intermediate performance due to its uniform heating process that minimized thermal degradation. Overall, non-thermal methods emerged as the most effective for preserving both aroma and phenolic profiles, followed by OH, while TP resulted in the greatest losses. These findings highlight the potential of non-thermal and alternative thermal technologies over thermal pasteurization to maintain the sensory and nutritional quality of fruit-based beverages.

The use of photoselective nets has gained interest in highbush blueberry production systems in recent years. Although some work has been conducted on their effects on the growth and development of the fruit, the performance of fruit grown under those nets after harvest has not been addressed yet. Here we focus on the performance of fruit grown under photoselective nets (exclusion, red, yellow, black) during long cold storage for the first time. The experiment was performed in two different years, monitoring morphological parameters, as well as primary and secondary metabolites using HPLC-MS and GC-MS. Minimal differences between treatments were noticed in fruit color, firmness and total soluble solids contents (TSS). In terms of fruit metabolism, two different periods were described during storage, with an inflection point at 14 days; in the first period, an increase in sugar content and a decrease in volatile content was observed, while after that, we found the opposite behavior. Overall, fruit grown under red nets showed the highest retention of secondary metabolites and the highest sugar/organic ratio, probably associated with a higher antioxidant capacity promoted by an increased red light proportion during the growth season. On the other hand, yellow nets showed the least favorable storage performance, as the light quality did not significantly improve the metabolism.

Bio-based solutions that promote plant growth, yields and functional quality of foods in primary production are gaining popularity in environmentally challenging conditions such as temperature fluctuations, late frosts and excess precipitation. This study was implemented to examine the foliar effect of microalgae biostimulants (three microalgae: Chlorella vulgaris, Scenedesmus vacuolatus and Coelastrella sp. in two concentrations ‒ 5 and 10