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Black soybean seed coat has a considerable content of anthocyanins which can provide a positive effect on the health of the consumers through food products enriched with the extracts of these valuable bioactive compounds. Nevertheless, the use of soybean seed coat, a by-product from soybean processing, additionally valorizes this raw material. The possibility of enrichment of sweet maize grains with anthocyanin extract was investigated. Several procedures with acetic acid were applied in the experiments of anthocyanins extraction from black soybean seed coat. During the marination process, the grains were stained, changing their standard yellow color to a crimson red. Since the brines with the addition of citric acid became cloudy (opalescent) after some time, lactic acid was used as an anthocyanin stabilizer in the continuation of the research. Depending on the extraction conditions, the spectrophotometrically determined content of total anthocyanins in the solution varied from 3541.90 to 5387.70 mg CGE/g d.m., and in the marinated maize grain between 179.89 and 286.05 mg CGE/g d.m. After seven days, the total anthocyanin content in the grain did not increase significantly, so this aging period was selected as optimal for marinating maize products.

Four commercial wholegrain flours made from differently colored kernels of maize genotypes produced in Maize Research Institute "Zemun Polje" were used as the subject of this study. Values of major chemical components as well as mineral nutrients, antioxidants and some vitamins of wholegrain flours obtained from white dent hybrid, yellow popping maize hybrid, red dent variety and blue popping maize landrace are presented. All flours had high fiber content (6.9-10.4%), while total protein ranged from 8.5% to 12.2%. A high level of anthocyanins was determined in blue popping maize wholegrain flour (910.0 mg CGE/kg), whereas yellow popping maize flour had a high content of total carotenoids (26.5 mg bCE/kg). Total antioxidant capacity was the lowest in white (15.50 mmol Trolox Eq/kg) and the highest in blue popping maize flour (37.6 mmol Trolox Eq/kg). All investigated wholegrain flours contained high levels of potassium and magnesium, as well as high content of trace elements, namely iron, zinc, copper and manganese. The maize flour is naturally gluten-free, which makes it highly suitable for persons susceptible to a gluten allergy and those with celiac disease. These results indicate that the wholegrain ZP maize flours can be used as functional food ingredients.

This study's primary objective was to assess the quality parameters of fifteen different genotypes of Serbian maize hybrids in order to establish whether they were suitable for making high-quality silage for ruminant feed. The study was carried out as a two-year field experiment at the Maize Research Institute in Zemun Polje, Serbia. Laboratory analyses included the yield structure of the examined maize hybrids, the evaluation of the composition of lignocellulosic fiber and the percentage of their ratios, as well as the in vitro dry matter digestibility and NDF digestibility of the whole plant samples. The Fisher's LSD test was used to statistically analyse the data, which were then reported as the mean and standard deviation of at least three independent replicates. The graphical representation of correlations among the observed parameters used the principal component analysis (PCA) method. All maize hybrids have displayed high-quality characteristics, which are required for the production of high-quality silage.

Five maize hybrids were used in this research: two yellow and one white dent, sweet hybrid, and yellow popcorn. Five brine recipes with acetic acid were examined, of which two with the addition of potassium sorbate. The brines with preservatives were stable for 16 months without colour changes of the liquid and corn cobs. The pH of brines ranged from 3.39 to 3.89. Canned hybrids ZP 366 and ZP 611k in brine without sugar, and with the addition of potassium sorbate and potassium metabisulfite marked as Number 5, showed the best sensory characteristics. The protein content determined in ZP 366 (9.56 %) and ZP 611k (10.23 %) did not vary significantly compared to whole-grain maize flour, while crude fibre content (7.67 and 6.88 %), and ash content (21.96 and 20.72 %) were significantly higher than in flour (crude fibre: 2.40; 2.64 %, ash:1.35; 1.48 %, respectively). This research will be continued in order to implement preliminary findings and new data on this subject.

The focus of this study is on the physical quality traits and starch composition of various maize kernel genotypes grown in Serbia. Furthermore, the aim was to determine the relationship among these quality traits. Results obtained from the Stenvert hardness test showed great variability among the maize samples. The portion of the hard endosperm fraction (HE) ranged from 53.29% to 76.28%. Test weight (TWt) and 1000-kernel weight (KWt) of 10 different ZP maize genotypes ranged from 782.69 to 907.39 kgm-3 and from 128.40 to 376.50 g, respectively. The specialty maize genotypes had the highest content of amylose (27.8% and 28.9%). Yellow dent genotype, ZP 606, had the lowest amylose content in the kernel (22.3%). The results suggested that the composition of starch granule differed depending on the hardness of the endosperm. The amylose content was highly correlated with the physical traits such as TWt, KWt, density and HE.

Maize is one of the most important field crops both in the world and in our country. All commercially grown maize hybrids can be classified into one of five elementary types: dent, flint, floury, popping and sweet maize. The objectives of this study were to characterize the grain chemical compositions of yellow-seeded and white-seeded maize dents, popping maize and sweet maize genotypes. The results show that grains contents of starch, protein, oil, crude fibre, and ash of four selected maize genotypes ranged in the intervals: 53.54-68.13%; 9.19-13.00%; 4.35-5.39%; 2.13-3.93% and 1.28-2.85%, respectively. The amylose to amylopectin ratio varied from 21:79 to 28:72, which is a principal property of normal maize starch. The content of lignocellulosic fibres: NDF, ADF, ADL, hemicellulose and cellulose ranged from 11.31-15.27%; 2.51-3.54%, 0.24-0.52%, 8.10-12.68% and 2.14-3.02%, respectively. The solubility index of albumin, globulin, zein and glutelin ranged from 9.46-29.42%, 5.64-13.13%, 21.11-28.10% and 18.81-23.69%, respectively

The influence of grain moisture content at harvest and at the moment of popping on popping volume and percentage of unpopped kernels was analysed. Four popcorn hybrids were studied. Hybrids were harvested when grain moisture content was: above 25%, between 20 - 25%, and below 18%. Each sample was popped at 20%, 18%, 16%, 14%, 12%, and 10% of grain moisture. All examined factors and their interactions significantly influenced both popping volume and percentage of unpopped kernels. The highest popping volume and the lowest percentage of unpopped kernels were observed at 14% grain moisture content. Hybrid ZP 608k had the highest popping volume and the lowest percentage of unpopped kernels at all treatments and overall. The lowest popping volume and the highest percentage of unpopped kernels were noticed for ZP 501k. The lowest percentage of unpopped kernels was observed in the last harvest term when grain moisture content was below 18%.

In this study 36 maize hybrids of different FAO maturity groups were observed in three successive years (2011, 2012 and 2013), on 8 locations. The main objective of this experiment was to observe the GxE interaction concerning yield, grain moisture, grain yield per ear and test weight. The experiment was set up according to the RCBD. Based on the obtained results average estimates, CV and overall ranking of hybrids were calculated. ANOVA was applied in order to estimate the effect of factors: genotype, environment and interaction. Thus the significance of all these factors was observed. Results of this research indicate the importance and necessity of performing multilocation and multiyear trials with the aim of observation and understanding the intensity of GxE interaction, as well as its influence on the grain yield and it components.

This research encompassed a total of 12 popcorn hybrids planted according to the RCBD in three replicates in Zemun Polje in 2016. The following traits were analyzed: grain yield (t/ha), kernel size, 1000 kernel weight, popping volume, percentage of unpopped kernels, and sensory characteristics (the appearance, taste, smell, tenderness, crispness, adhesiveness to the teeth, presence of pericarp and overall taste acceptability of popcorns). The analysis of variance showed significant differences between the popcorn hybrids with regard to the traits analyzed. The grain yield ranged from 4.78 t/ha (ZP 644/1k) to 7.38 t/ha (ZP 557/1k). The lowest popping volume was noticed in ZP 501k (28 cm3/g), whereas the highest popping volume was found in the lower-yielding hybrid ZP 544/1k (40.17 cm3/g). The percentage of unpopped kernels was very low and it ranged from 0.66% to 4.57%. The analysis of sensory characteristics of popcorns also showed differences between 12 popcorn hybrids.

Cold test (CT) is a valuable method of assessing maize seed vigour. Although widely used CT is not standardized because of variations in CT procedures. The objective of this study was to evaluate seed vigour of 15 maize inbred lines developed at the Maize Research Institute Zemun Polje, using two different substrates (soil and sand) in a severe CT (7.5°C for 10 days followed by 7 days at 20/30 °C). Statistical analysis showed that inbred lines differ significantly in seed vigour, and no difference between two applied substrates in CT. Coefficients of variation were lower in CT with sand (6.05 %), compared to the CT with soil (6.74%) due to variation in soil quality and presence of soil-borne pathogens. Both CT procedures were highly correlated with field emergence. Results of this research indicate that CT with sand is appropriate for testing maize seed vigour, with the potential for standardization.

The percentage of moisture content at the moment of popping has the most significant impact on the popping volume of popcorn. In this research we observed the influence of the optimal moisture content of 14.2 % and lower moisture content (12, 10 and 8 %) on the popping volume of twelve popcorn hybrids. At moisture content of 14.2 % the highest popping volume was observed in ZP 611k (41.33 cm3/g). Four popcorn hybrids had very good popping volume of over 39 cm3/g and four hybrids achieved medium popping volume of 36-39 cm3/g, while three popcorn hybrids had unsatisfactory popping volumes below 36 cm3/g. Hybrid ZP 501k was the one with the lowest popping volume of 28.67 cm3/g. By reduction of percentage of moisture content in the grain, significant reductions in popping volumes were observed - in average 37.68, 27.97, 16.93 and 3.79 cm3/g, respectively. Analysis of variance showed that genotype, moisture content and their interaction had significant impact on the popping volume.

These experiments were conducted in the period 2003-2008 in Zemun Polje. Five hybrids were investigated in six sowing dates - on April 5th (Sd1), 15th (Sd2) and 25th (Sd3), and on May 5th (Sd4), 15th (Sd5) and 25th (Sd6). Three unfavorable years for the maize production were distinguished in this period: 2003 with 210.0 mm, 2007 with 290.1 mm and 2008 with 224.6 mm of precipitation; 2005 was moderately favorable, with 387.4 mm of precipitation. Two years were favorable for the maize production, both in terms of precipitation amounts and distribution: 2004 with 427.6 mm and 2006 with 417.1 mm. The highest average yield was achieved in Sd2 (11.21 t/ha - 100%). On the other April sowing dates, average yield was lower: on Sd1 - 11.04 t/ha (98.48%), on Sd3 - 10.97 (97.86%). The effects of the May sowing dates were significantly lower comparing with the Sd2: Sd4 - 10.53 t/ha (93.93%), Sd5 - 10.46 t/ha (93.31%) and Sd6 - 9.71 t/ha (86.62%). The highest yielding hybrid was ZP 684 (11.16 t/ha). These results doubtlessly point to the mid April sowing date as an optimum for maize in Serbia.

The experiment with 12 popcorn hybrids was set up according to the RCB design in three replicates. Examined traits were: grain yield (GY), popping volume (PV) and number of kernels per 10g (NK). ANOVA showed statistical differences among examined genotypes according to all three traits. Grain yield of the hybrids varied from 3.36 t/ha (ZPSK 645/1k) up to 6.07 t/ha (ZPSK 611k). The lowest popping volume had hybrid ZPSK 501k (27.33 cm3/g), which is considered unsatisfactory, while five hybrids had good popping volume over 38.00 cm3/g. Negative correlation was determined between GY and PV (-0.52), which although wasn't significant indicated that higher yielding hybrids often have lower popping volumes. Significant correlation was between GY and NK (-0.70*), and between NK and PV (0.66*). These results point out to the fact that breeding of popcorn is very complex process, for there is necessity of producing high yielding and good popping quality hybrids, which is mostly contradictory.