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The paper presents the results of three-year research on technological properties of fruits and quality of compotes made of four Novi Sad (NS) apricot cultivars (NS-4, NS-6, Novosadska rodna and Novosadska kasnocvetna) and five selections (SK-1, SK-3, SK-5, SK 13a and SK 16a). Apricots for this research on technological properties and making compotes were harvested in a collection of apricot genotypes of the Department of Fruit Growing, Viticulture, Horticulture and Landscape Architecture of the Faculty of Agriculture in Novi Sad, in the site “Rimski šančevi” (45º 20̓ 00ˮN,19°51̓ 100ˮE). Technological properties were investigated at the Faculty of Technology in Novi Sad and a laboratory of “Soja-Protein, AD Bečej” company. The investigated technological properties were: the amount of dry matter, total and reducing sugars, total acids, sucrose, total pectins, cellulose and mineral matter. These properties of NS cultivars and selections were compared to Hungarian Best (as a standard). The fruits of the NS cultivars and selections expressed better technological properties than Hungarian Best. The properties such as colour, aroma, taste, condition and consistency were sensory evaluated, with a method of giving points, used at the Novi Sad International Agricultural Fair. The compotes of the NS cultivars and selections were given more points than the compote made of standard. As for the total organoleptic properties, the compotes of selections SK-3, SK 13a and SK-5 stand out.

In this paper, we present the morphological characteristics of the seed and micromorphological, anatomical and chemical characteristics of the seed coat of pea (Pisum sativum L.) genotypes, Jezero, Javor and NS Junior. Our aim was to investigate whether these genotypes can be differentiated based on seed coat morphoanatomical characteristics, depending on the harvest treatment. The observations and measurements of seed coat cross-sections were performed using light microscopy. The seed coat surface was observed using SEM. A tuberculate seed coat surface characterized all examined pea genotypes, and the average diameter of the tubercle was about 12 μm. Statistical and laboratory analyses revealed that major damage was the most frequent defect type as the result of mechanized harvest in all the examined genotypes. Genotype NS Junior had the shortest seed length (6.1 mm). Micromorphological analysis revealed that the seed surface was tuberculate in all genotypes. The genotype Jezero had the highest number of tubercle ribs (11.0) and a significantly higher proportion of parenchyma tissue (50.6%), while NS Junior was characterized by the greatest share of macrosclereids (49.8%). The highest number of osteosclereids (832/mm2) was counted in genotype Javor. In addition, genotype NS Junior stands out due to the highest percentage of crude fiber (62.75 g/100g) in the seed coat. There was a marked difference among the studied genotypes with regard to the seed coat morphoanatomical characteristics, which is confirmed by the results of multivariate discriminant analysis (MDA). These results suggested that the morphological, micromorphological and anatomical characteristics of the seed might have an impact on the seed coat damage level at harvest. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. 31024 and Grant no. 173002]

The objective of this research was to optimize the vacuum drying of frozen blueberries in order to preserve health benefits phytochemicals using response surface methodology. The drying was performed in a new design of vacuum dryer equipment. Investigated range of temperature was 46-74°C and of pressure 38-464 mbar. Total solids, total phenolics, vitamin C, anthocyanin content and total color change were used as quality indicators of dried blueberries. Within the experimental range of studied variables, the optimum conditions of 60 °C and 100 mbar were established for vacuum drying of blueberries. Separate validation experiments were conducted at optimum conditions to verify predictions and adequacy of the second-order polynomial models. Under these optimal conditions, the predicted amount of total phenolics was 3.70 mgCAE/100dw, vitamin C 59.79 mg/100gdw, anthocyanin content 2746.33 mg/100gdw, total solids 89.50% and total color change 88.83. [Projekat Ministarstva nauke Republike Srbije, br. TR 31044]

The influence of protective properties of packaging materials and modified atmosphere on quality changes of dried apricot is shown in this paper. In our investigation, we used four different characteristic combinations of packaging materials with different barrier properties for packaging of dried apricot: polyester-polyethylene (PET/PE), paper-polyethylene (PAP/PE), paper-aluminum-polyethylene (PAP/Al/PE), polyester-aluminum-polyethylene (PET/Al/PE) and two different atmospheric conditions: normal and modified. Modified atmosphere was made in laboratory conditions: CO2 about 30%, N2 about 60%, and the rest is O2. Over the 12-month storage period, the changes in the water content, water activity (aw) and overall polyphenol content were monitored in the packed product.

Influence of chemical structure on the lipophilicity of isolated free carotenoids from paprika oleoresin has been studied by QSRR approach (Quantitative structure-retention relationship). The chromatographic behavior of these compounds was investigated by using reversed phase high-pressure liquid chromatography (RP HPLC). Retention mechanism has been determined using the following mobile phase: acetone -water, on reversed - phase column (SB-C18). A variety of lipophilicity parameters (logP) were calculated by use of different software products. On the basis of correlations, the nonlinear structure-activity models were derived between the retention constants, tr (retention time of investigation compounds), and logP values. Five high quality QSRR models were found to have a good predictive ability and close agreement between experimental and predicted values. The study showed that the retention constants can be used as a measure of lipophilicity of investigated compounds at a high significant level. [Projekat Ministarstva nauke Republike Srbije, br. 172012, br. 172014 i br. 31055]

This study investigates variability of tomato genotypes based on morphological and biochemical fruit traits. Experimental material is a part of tomato genetic collection from Institute of Filed and Vegetable Crops in Novi Sad, Serbia. Genotypes were analyzed for fruit mass, locule number, index of fruit shape, fruit colour, dry matter content, total sugars, total acidity, lycopene and vitamin C. Minimum, maximum and average values and main indicators of variability (CV and σ) were calculated. Principal component analysis was performed to determinate variability source structure. Four principal components, which contribute 93.75% of the total variability, were selected for analysis. The first principal component is defined by vitamin C, locule number and index of fruit shape. The second component is determined by dry matter content, and total acidity, the third by lycopene, fruit mass and fruit colour. Total sugars had the greatest part in the fourth component.

Vitamin C is an essential vitamin for human nutrition; with the L-ascorbic acid (AA) being the active form of vitamin C. Hence, determination of the L-ascorbic acid in the natural and processed foods is very important. In the past, plenty of methods based on the reversible redox reaction of AA oxidation/DHA reduction were developed. Because of L-ascorbic acid instability in aqueous solutions, it is useful to analyze various types of extraction. The aim of this study is to compare three different methods and three different extractants for the L-ascorbic acid determination. Fruits (kiwi, lemon, orange, and grapefruit) were purchased from a local market. The L-ascorbic acid in these four samples was determined by the three different methods: the AOAC, the HPLC method with three different types of extractions, and the colorimetric method using ascorbate-oxidase. For the HPLC measurements, one part of the fruits was extracted with distilled water, the second with potassium hydrogen phosphate, and the third with 3% meta-phosphoric acid (MPA) in 8% acetic acid. The HPLC measurements of each sample were repeated three times, the AOAC titration was repeated five times, and in the calorimetric method three measurements were performed. The results were statistically evaluated related to sample basis. Statistical analysis shows that there is a significant difference between the results for all three methods of extraction for all samples, except for the grapefruit sample where no significant difference was observed between the results obtained after the buffer extraction (E2) and the metaphosphoric acid in acetic acid extraction (E3). Discriminative analysis for the HPLC determinations proves that there is a clear difference and defined border between the samples in relation to the methods of extraction during the HPLC determination.

The main chemical composition, contents of total phenolic (TPh), total flavonoid (TF), and total monomeric anthocyianin (TMA), as well as the antioxidant activity of two raspberry cultivars (Meeker and Willamette), two blackberry cultivars (Čačanska bestrna and Thornfree) and wild bilberry were studied. The raspberry cultivars had the highest total solids among fruits investigated. Bilberry fruits had the highest sugar-to-acid ratio. Blackberry fruits were richer in crude fibers (cellulose) in comparison to raspberry and bilberry fruits. The content of pectic substances was highest in the bilberry. Also, bilberry had a highest content of TPh (808.12 mg GAE/100 g FW), TF (716.31 mg RE/100 g FW) and TMA (447.83 mg CGE/100 g FW). The antioxidant activity was evaluated spectrophotometrically, using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity assay. The DPPH free radical scavenging activity, expressed as the EC50 value (in mg of fresh weight of berry fruit per ml of the reaction mixture), of bilberry (0.3157 ± 0.0145 mg/ml) was the highest. These results also showed that the antioxidant value of 100 g FW bilberry, raspberry - Willamette, raspberry - Meeker, blackberry - Čačanska bestrna and blackberry - Thornfree is equivalent to 576.50 mg, 282.74 mg, 191.58 mg, 222.28 mg and 272.01 mg of vitamin C, respectively. There was a significant positive correlation between the antioxidant activities and content of total phenolics (RTPh 2=0.9627), flavonoids (RTF 2=0.9598) and anthocyanins (RTMA 2=0.9496) in berry fruits. [Projekat Ministarstva nauke Republike Srbije, br. TR 31044]

The macro- and micro-chemical composition, as well as antioxidant activity of two strawberry cultivars, Marmolada and Clery, were studied. Results showed a noticeable difference in the sugar, protein and pectin contents. Clery had 6.92% and Marmolada 4.93% of total sugar. Also, protein and pectin contents were higher in the Clery cultivar. No significant difference was observed in acidity, as well as in ash and cellulose content. Marmolada had a higher content of total phenolics and flavonoids (228.04 mg GAE /100 g FW and 136.01 mg RE/100 g FW, respectively ). The anthocyanins content in Marmolada (32.0 mg CGE/100 g FW) was slightly lower than in Clery (36.0 mg CGE/100 g FW). The antioxidant activity was evaluated spectrophotometrically, using 2,2-diphenyl- 1-picrylhydrazyl (DPPH) radical scavenging activity assay. The DPPH free radical scavenging activity, expressed as EC50 value, of Marmolada (0.77 mg/ml )was higher than of Clery (0.83 mg/ml). There was a significant positive correlation (R2>0.90) between the concentration of phenolics/flavonoids/anthocyanins and DPPH radical scavenging activity of both strawberry cultivars. These results also showed that the antioxidant value of 100 g FW Marmolada and Clery is equivalent to 237.91 mg and 219.01 mg of vitamin C, respectively.

Coagulation and flocculation are the most used methods for removal of turbidity of water. Recently, many studies have focused on the investigation of natural coagulants for this purpose. In view of the fact that extracts of common bean have coagulation activity, this study is concerned with the chemical composition of these extracts and their influence on the coagulation activity. Extraction was conducted with distilled water, 0.5M NaCl and 1M NaCl and total sugars content, proteins, phytic acid and total phenolics content and their coagulation activity were determined in the obtained extracts. These experiments confirmed that an extraction time of 10 minutes is sufficient for the extraction of active coagulant components from common bean seeds and that water is satisfactorily efficient and most economical solvent.

In this study, 14 newly synthesized s-triazine derivatives were investigated by means of reversed-phase thin-layer chromatography (TLC) on C-18 stationary and two different mobile phases: acetonitrile-water and methanol-water. Quantitative structure-retention relationship (QSRR) was developed for a series of s-triazine compounds by the multiple linear regression (MLR) analysis. An MLR procedure was used to model the relationships between molecular descriptors and retention of s-triazine derivatives. Physico-chemical molecular descriptors were calculated from the optimized structures. Statistically significant and physically meaningful QSRRs were obtained.

Considerable attention has been paid to the analysis of chemicals in the s-triazine group, due to their widespread use in agricultural chemistry and their subsequent impact on biological systems. For initial chemical screening of the activity of newly synthesized compounds, it is recommended to determine their lipophilicity and physico-chemical property in relation to biological activity. Lipophilicity is difficult to quantify. The most widely accepted measure of lipophilicity is the octanol-water partition coefficient. Measurement of the octanol-water partition coefficients is achieved by an alternative method, i.e. reversed-phase liquid chromatography. Reversed-phase thin-layer chromatography (RP TLC) is a rapid method for the analysis of large number of s-triazine type compounds. Certain relationship between the structure of s-triazine compounds and their mobility on silica gel impregnated with paraffin oil have recently been demonstrated. The retention behavior of compounds in various chromatographic systems strongly depends on their physico-chemical properties. Recently, much effort was given in finding adequate mathematical model relating the retention of the given analyte to its physico-chemical and structural parameters (descriptors). These correlations are known as quantitative structure-retention relationships (QSRR), which offer a powerful tool for the prediction of separation behavior. The QSRR equations describing retention constants RM0, determined for different modifiers in mobile phase in terms of logarithms of n-octanol-water partition coefficients, were derived. The partition coefficients (AlogPs, AClogP, AB/logP, milogP, AlogP, MlogP, logPKowin, XlogP2, XlogP3, ACDlogP i ClogP) were calculated by application of different software packages. The goal of this paper was to select the logP data and TLC system that best characterize octanol/water partitioning and thus the lipophilicity of the investigated molecules.

The influence of particle diameter of ground paprika on its colour was examined in this study. Six samples of industrial ground paprika, from various phases of milling, and different particle size were purchased from the factory. Extractable colour (ASTA) and surface colour (L, a

Essential oils extracted from spices, as natural antimicrobial agents, attract particular attention due to their possible role in food protection from microorganisms, and their nontoxicity, in contrast to the synthetic preservatives. In this work, inhibitory effect of Allium ampeloprasum and two onions (Allium cepa), Junski srebrnjak and Kupusinski jabučar, essential oils in different concentrations (1, 4, 7 and 10%) on three yeasts (Saccharomyces cerevisiae, Candida tropicalis and Rhodotorula sp.) and three moulds (Aspergillus tamarii, Penicillium griseofulvum and Eurotium amstelodami) was investigated. All three essential oils showed the strongest inhibitory effect against S. cerevisiae in concentration of only 1%. Among onions, Kupusinski jabučar essential oil had stronger influence to C. tropicalis, while Allium ampeloprasum essential oil did not show any influence on this yeast. Rhodotorula sp. was influenced only by Allium ampeloprasum essential oil. The strongest inhibitory effect on A. tamarii showed Kupusinski jabučar (57% of inhibition, in concentration of 10%), while on P. griseofulvum, the strongest influence showed Allium ampeloprasum essential oil (78.3% of inhibition, in concentration of 10%). Junski srebrnjak and Kupusinski jabučar essential oils, in concentrations of 7 and 10% respectively, completely inhibited the growth of E. amstelodami.

Dietary fibers are one of the main nutritive components, along with proteins, fats and oils, carbohydrates, minerals and vitamins. Also, they are one of the basic parameters of dry beans technological quality and nutritive value. Physical characteristics and the main chemical composition of sixteen dry bean varieties (Phaseolus vulgaris) had been examined in this study. Using statistical analyses, correlation between certain parameters of chemical composition was established.

This paper shows that it is possible to improve antioxidant activity of apple juice by extraction of polyphenolic compounds from apple pomace, as waste, and their addition to the apple juice. Raw apple juice was prepared by pressing of apple mash. After thermal treatment of raw apple juice, depectinisation, additional clarification and filtration, the clarified juice was obtained. In raw and clarified apple juice soluble solids, acidity, reducing sugar, total sugars and brown component content were determined, as well as total dry matter, ash, acidity, reducing sugar, total sugars, total pectins, cellulose and starch content in apple mash and pomace. The total cotent of phenolics in clarified apple juice and apple pomace extract, determined spectrophotometrically using the Folin- Ciocalteu reagent, was 0.496 mg/ml and 6.505 mg/g, respectively. The antioxidant activity of clarified and polyphenol-enriched clarified juice (with addition of apple pomace extract in the concentrations 0.05 g, 0.1 g, 0.5 g and 1 g of phenolic compounds per liter of clarified apple juice) was examined on stable 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radicals. Based on the obtained results it can be concluded that polyphenol-enriched clarified juice was more effective on DPPH radicals than the clarified apple juice.

Fast frozen blackberry partially change its surface color from characteristic black to copper-redish color. This change decreases the market value, especially when the product is intended for export. For these reasons classic tunnels for slow freezing are being more widely used nowadays. In order to clarify mentioned phenomena, a detailed monitoring of preparation process and freezing, as well as changes of frozen blackberry fruits in industrial conditions was carried out. Along with sensory evaluation of surface color changes, chemical analysis of reference parameters of fresh and frozen fruits were performed. The results of sensory evaluation confirmed evident color change of fruits frozen by slow (and fast) treatment; the chemical analysis confirmed unchanged total solids and anthocyanin content, as well as changes in pH value and vitamin C, in comparison to fresh blackberry fruits.

The presence of fungi in cinnamon, marjoram, caraway and clove was investigated. Total fungal counts determined on SMA nutritive medium ranged from 8.0 (clove) to 3.3 × 104 per g (caraway) and from 6.0 to 5.2 × 104 per g on MY50G medium for the same spices. The most frequent contaminants of spice samples were the genera: Eurotium (90%), Aspergillus (80%), Penicillium (75%), Cladosporium (45%), Rhizopus, Scopulariopsis and Syncephalastrum (25%). Producers of sterigmatocystin (80%) were dominant. Producers of aflatoxin (60%) and ochratoxin A (30%) were isolated from the samples.

Spices are widely used in food processing. One of the main disadvantages of spices application is their frequent microbiological spoilage. Health benefits (microbiological status, mineral and heavy metal content) of commercial ground paprika (Capsicum annuum), as well as the colour and microbiological status of its conventional and supercritical oleoresins were examined in this work.

Red pepper (Capsicum annuum L.) is one of the most important vegetables in the world. The main ground pepper quality attributes are extractable color, surface color, qualitative and quantitative carotenoid content. In this work, the influence of heat treatment on ground pepper quality was investigated. Microbiological status was examined in non-sterilized and sterilized ground pepper. Color changes were assessed by measuring the extractable color (ASTA) and surface color, using a photocolorimeter. The obtained results showed that at the end of experiment, non-sterilized samples had higher color values in comparison to the sterilized ones. Also, color deterioration was heightened at room temperature.

Dried fruits are very delicate to biochemical changes during storage, due to low water content, as well as low aw value. The shelf life of these products depends on aw value. Materials for dry fruits packaging are necessary to have appropriate barrier characteristics for water, oxygen, nitrogen and carbon dioxide molecules, as well as for electromagnetic rays, especially those with low wavelengths in UV region. During storage of packed dry fruits, qualitative changes, influenced by different packaging materials, may occur. The results of tested characteristics of different packaging materials, combination and their barrier features, as well as the qualitative changes of packaged dried apples are presented in this paper. The qualitative changes of color and sensory characteristics of packaged dried apples point out to influence of the type, combination as well as the barrier features of used packaging materials. .

There have been an increasing interest of consumers for a ide variety of pickled vegetable products worldwide. Regarding the regional vegetable supplies and relatively poor assortment of ready-to-use products, the need to broaden the offer of domestic pickled vegetables at the market came out. In this work recipes for different vegetables, spices and condiments were developed. The best graded samples were analyzed for their main chemical composition (dry matter, proteins, oils and fats, total acidity, total sugars, sucrose, starch, cellulose, pH) and energy- values.

Compositional characteristics of seven lines of tomatoes have been determined. The following parameters were evaluated: dry matter, acidity (citric acid equivalent), Ca-pectate, ash, cellulose, sugars (total, reducing sugars, sucrose), mineral substances (N, P, K, Ca, Na), surface color and carotenoid content. From a compositional viewpoint, there were no significant differences between lines, but in cellulose, sucrose, mineral substances, carotenoid content, and surface colour parameters, a*, b*, L and h°. .

Green pea (Pisum sativum L.) has a long tradition in Serbia and Montenegro as a processing crop. Short growing season, relatively simple production, pleasant taste and high nutritional value stimulate both production and consumption of peas. The objective of this paper is to present the main characteristics of two pea varieties, domestic cultivar Tamis and imported cultivar Jof and the influence of prolonged time between harvest and processing on the changes of main characteristics. Both cultivars have grains of very high quality that can be used for industrial processing as well as for garden growing (the green market). In the present paper the results of one-year study are shown: cultivar characteristics, growing season length, and physico-chemical (tenderometer value (TM), dry matter, alcohol insoluble solids (AIS), sugar and starch) measurements for texture determination. According to the results, the optimal way of processing for each variety was recommended. .

Powders of pepper were stored at ambient temperature, exposed to daylight The final quality was evaluated by measuring the extractable colour by the American Spice Trade Association (ASTA). Also, the possibility of using surface colour measurement, as a supplement to extractable colour measurement was investigated. The use of the chromatic attributes L, a and b, suggested by the Commision Internationale de l'Eclairage (CIE), i.e., of the CIELAB space, made it possible to find the correlation between ASTA and apparent colour of paprika.

The number of people suffering from insulin-dependent (Diabetes Melitus type I) and insulin-independent (Diabetes Melitus type II) is huge, and the number of potential diseased is in permanent rise. For that reason products with reduced amount of sugar have become very popular. Factory "Srbijanka" Valjevo manufactures reduced–sugar marmalades from apricot peach, strawberry, apple and orange. Low–metoxyl pectins and high-grade locust bean gum were used as gelation agents. Sensory evaluation and energy value of these marmalades were determined and all samples were highly graded. All marmalades belonged to the group of low-calorie (dietetic) products.