Raspberries are one of Serbia’s best-known and most widely exported fruits. Due to market fluctuation, producers are looking for ways to preserve this fresh product. Drying is a widely accepted method for preserving berries, as is the case with freeze-drying. Hence, the aim was to evaluate convective drying as an alternative to freeze-drying due to better accessibility, simplicity, and cost-effectiveness of Polana raspberries and compare it to a freeze-drying. Three factors were in experimental design: air temperature (60, 70, and 80 °C), air velocity (0,5 and 1,5 m · s−1), and state of a product (fresh and frozen). Success of drying was evaluated with several quality criteria: shrinkage (change of volume), color change, shape, content of L-ascorbic acid, total phenolic content, flavonoid content, anthocyanin content, and antioxidant activity. A considerable influence of convective drying on color changes was not observed, as ΔE was low for all samples. It was obvious that fresh raspberries had less physical changes than frozen ones. On average, convective drying reduced L–ascorbic acid content by 80.00–99.99%, but less than 60% for other biologically active compounds as compared to fresh raspberries. Convective dried Polana raspberry may be considered as a viable replacement for freeze-dried raspberries.

Cornelian cherries (Cornus mas L.) were dried by convective, vacuum, and freeze drying. The main goal was to investigate changing of physico-chemical properties of cornelian cherries during different drying techniques. Moisture content, water activity, total color change, shear force, rehydration power, total phenolic, flavonoid and anthocyanin compounds, ascorbic and organic acids, and antioxidant activity were used as the most suitable quality indicators. The lowest moisture content, water activity, total color change and the lowest content of investigated organic acids, the highest rehydration power, and also the lowest loss of ascorbic acid were obtained in vacuum dried samples. In freeze-dried samples, the lowest shear force and the highest antioxidant activity were observed. The lowest loss of phenolic, flavonoid, and anthocyanin compounds were also obtained in freeze-dried samples. Eight empirical models were used for the description of vacuum drying process, and model Midilli et al. was selected as the most suitable. Practical applicationsCornelian cherries present very popular sort of fruit with irresistible taste and specific texture.They also possess significantly high content of bioactive compounds. Drying parameters, mostly temperature, influence negatively on preservation of sensory and nutritive properties of cornelian cherries during drying. Thus, investigation of different impacts of each drying technique on physico-chemical parameters of cornelian cherries and also kinetics of cornelian cherries vacuum drying are useful both in scientific field and in industrial conditions. Based on this research, it could be seen, which drying parameters influenced the best on preservation of the most important physico-chemical properties of fresh cornelian cherries. Also, the most suitable empirical model used for the description of vacuum drying of cornelian cherries was observed.

Drying of stone fruit with different techniques and characterization of physical, chemical and biological properties of convective dried, vacuum dried and lyophilised stone fruit, as well as analysing and structuring the data sets by principal component analysis (PCA) were obtained in this paper. Drying technique significantly influenced the shear force, hardness, springiness and cohesiveness of dried apricot NS4 (Novi Sad 4) samples (p < .05); the total phenolic, flavonoid and monomeric anthocyanin content of dried sour cherry Feketicka, sweet cherry Lapins, sweet cherry Sweet Heart and plum Toptase samples and also the antioxidant capacity of dried sour cherry Feketicka, plum Anna Spath and peach Lela samples. The most noticeable differentiations of the stone fruit groups of samples dried with convective and vacuum drying and lyophilisation were observed in raw and dried sour cherry Feketicka and Erdi Botermo samples. Practical applications The results and conclusions obtained in this research have various application in food industry in many aspects. First, part of the fruit varieties investigated in this study were developed at the Faculty of Agriculture and their application in the fruit drying industry has been thoroughly investigated. In addition, application of different drying techniques on different stone fruit species were applied in this research. Finally, the possibilities of preservation the most important quality indicators of dried fruit was observed. The impact of obtained conclusions and results in the field of agricultural and food industry is significant, since they could be applied in the industrial processes.

Sweet cherries (Prunus avium) belong to the group of stone fruit (Prunus spp.) and they present a rich source of phenolic, flavonoid, and anthocyanin compounds (Ballistreri et al., 2013; Bastos et al., 2015). These components contribute to potent antioxidant activity of sweet cherries. Sweet cherries possess delicious taste and attractive appearance and they are also very good source of many phytochemicals which contribute to a healthy diet (Nawirska-Olszańska et al., 2017). In order to preserve these components and to keep sweet cherry available through the whole year, different preservation techniques such as freezing and drying could be applied. Dried fruit is mainly produced by solar drying and conventional air drying. According to Ochoa, Kesseler, Pirone, Márquez, and De Michelis (2007), shrinkage phenomenon of whole sweet cherry fruits during

Pulses are edible seeds of plants belonging to the legume family, which are of great importance for human and animal nutrition. In this study, several nutrients, antinutrients and bioactive compounds were quantified in the seeds of ten pulses, i.e., common and runner beans, field peas, lupins (white, blue and yellow), faba beans, lentils (brown and red) and chickpeas. Homogenised, air-dried seed samples were analysed for various parameters: protein (18.0–43.1%), fat (0.6–18.5%) and phytic acid content (507–2566 mg/100 g dry weight (DW)), phenolic profile (27 phenolic compounds in total) and multi-mineral composition. The analysed phenolic compounds mainly belong to phenolic acids (hydroxybenzoic acids and hydroxycinnamic acids) and/or flavonoids (flavones, flavonols and flavanols). Total phenolic content (TPC) ranged from 719 μg/g DW in chickpeas to 5012 μg/g DW in common beans. A total of ten elements belonging to macro- (Mg, P, S, K and Ca) and micro-minerals (Cr, Mn, Fe, Zn and Mo) were determined. Using cluster analysis, pulses were divided into three groups according to the parameters studied: 1. common and runner bean; 2. field pea, white and blue lupin, faba bean, red and brown lentil and chickpea; and 3. yellow lupin. The most varying phytochemicals in terms of their content in the analysed pulses were phytic acid, quinic acid, catechin and TPC. A perfect positive significant Pearson correlation (1.00) was observed for six pairs of variables within the group of phenolic compounds.

The influence of biostimulants (B) and nitrogen (N) fertilization on the yield and quality of onions were investigated. Experiments in the field with directly seeded (DS) onions and those from sets (FS) were carried out in 2021 in the Autonomous Province of Vojvodina (Serbia). HumiBlack® (B1), Tifi® (B2), and Agasi® (B3) were used as B, and there was a control without B. Four N doses were used: 64, 100, 150 (standard dose), and 200 kg N/ha. The highest yields of DS onions (63.9 t/ha) and FS onions (52, 1 t/ha) were measured on treatment B2 × 150 kg N/ha. The highest total sugar content (80.6 g/100 g DM) was measured in FS onions under treatment B2 × 100 kg N/ha. Total nitrogen and protein content were the highest in DS onions treated with B2 × 200 kg N/ha, where total nitrogen was 2.3 g/100 g DM and protein content was 14.5 g/100 g DM. Depending on B and N, titratable acidity ranged from 1.7 to 3.6 g/100 g DM. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) were used to analyze onions and showed that FS onions have lower values of total phenolics and crude fiber content, DPPH, FRAP, and ABTS compared to DS onions. In this study, a chemometric approach was suitable for grouping onions according to treatment effect and main interactions between B and N.

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Sustainable extraction techniques (ultrasound-assisted extraction (UAE), microwave-assisted extraction (MAE), and pressurized-liquid extraction (PLE)) were applied and compared with conventional solvent extraction to evaluate their efficiency in maximizing the bioactive compound content and antioxidant activity of black and red currants. The influence of ethanol concentrations (30%, 50%, 70%) were studied in all extraction methods, while different temperatures (30, 50, 70 °C/80, 100, 120 °C) were evaluated in UAE and PLE, respectively. Generally, higher total phenolics were determined in black currant extracts (1.93–3.41 g GAE/100 g) than in red currant extracts (1.27–2.63 g GAE/100 g). The results showed that MAE was the most efficient for the extraction of bioactives from black currants, with 3.41 g GAE/100 g and 0.7934 g CE/100 g, while PLE provided the highest TP and TF for black currant samples (2.63 g GAE/100 g and 0.77 g CE/100 g). Extracts obtained by MAE (10 min, 600 W, 30% ethanol) and PLE (50% ethanol, 10 min, 120 °C) had the highest antioxidant activity, as determined by various in vitro assays (DPPH, FRAP, and ABTS). In conclusion, sustainable extraction techniques can be considered an efficient tool to maximize the content of bioactive antioxidants from black and red currants.