Mycotoxins are toxic secondary metabolites of fungi that contaminate a large variety of foods and have toxic effects on humans. The best protection against mycotoxins is to monitor their presence in food. This paper shows the screening results of mycotoxins present in 76 samples of different groups of grain foods. Samples of grain food were analyzed for contamination with aflatoxins, ochratoxin A, zearalenone, fumonisins and deoxynivalenol. Analysis were conducted using competitive enzyme-linked immunosorbent assay (ELISA). None of the samples was contaminated with aflatoxins. The most predominant mycotoxin was ochratoxin A with the mean level of 4.84 ± 4.49 ppb in 19.7% of the examined samples. Zearalenone, fumonisins, and deoxynivalenol were found in 9.21, 14.5 and 3.9% of the samples, respectively. Mycotoxin content in the investigated samples was compared with the regulations of Serbia and those of the European Union

The change of paprika surface colour during three years of storage was monitored by measuring CIEL*a*b* colour parameters once a year. Ten commercial and three branded paprika samples, originating from Hungary, Austria and Serbia, were stored in original packaging at ambient temperature in dark during the storage period. The colour of paprika powder was measured by Chroma Meter CR-400 (Konica Minolta, Japan), using attachment for granular materials CR-A50. Directly measured colour parameters were CIE L* (lightness), a* (+a* = redness,-a* = greenness), b* (+b* = yellowness,-b* = blueness) and dominant wavelength (DWL), while derived colour parameters were chroma (C*), hue angle (h°), and total colour change (ΔЕ). Paprika samples had similar granulation, and therefore it was concluded that it did not influence the colour reflection. The change of reflected colour of paprika powder during storage can be characterized by increase of CIE L* and b* colour values and decrease of a* colour value. Therefore, chroma values remained almost unchanged, while hue angle showed shift in spectrum from red-orange to orange-yellow, similarly to dominant wavelength. The paprika samples changed their colour most rapidly during the first year of storage, except the branded paprika from Serbia. Commercial paprika samples from Serbian market changed their colour more rapidly comparing to other investigated samples.

Polymeric wheat endosperm proteins, especially the high-molecular-weight glutenin subunits (HMW-GS), are probably the most interesting protein fraction giving the essential information about the bread-making quality of wheat flour.A relatively new method that shows great potential for a fast, reliable and automatable analysis of protein purity, sizing and quantification is microfluidic or Lab-on-a-Chip (LoaC) capillary electrophoresis. This aim of this work was to explore the possibilities of implementation of LoaC method to analysis of protein samples isolated from a Serbian common wheat variety, emphasizing the steps that might bring uncertainties and affect reproducibility of obtained glutenin subunits quantitation results. A good resolution of protein bands in a molecular weight range of 14.0 to 220.0 kDa was achieved. The reproducibility of HMW-GS sizing and quantitation were good, with the average coefficient of variation values of 1.2 and 12.2%. The ratio of HMW-GS to low-molecular-weight glutenin subunits (LMW-GS) was about 20%. The investigation ruled out influences of the extract solution addition and the buffer addition steps of the applied method, as well as the individual chip influence on GS quantitation results. However, there was statistically significant difference between HMW-GS quantitation results of multi-step and one-step extraction procedures applied prior to glutenin subunits extraction step.

The influence of post-harvest ripening conditions of pepper Aleva NK picked in red maturity stage on the composition of volatiles in spice paprika was investigated by GCMS. The post-harvest ripening in the dark and under daylight was conducted under semicontrolled conditions for two weeks. The obtained chromatograms indicated that the aroma of investigated spice paprika consisted of a large number of volatile compounds regardless of the application and conditions of the post-harvest ripening. The main volatiles of the analyzed paprika samples were fatty acids and their esters, terpenes and terpenoides and aldehydes and ketones. The share of fatty acids and their esters decreased during the post-harvest ripening, and the ripening in the dark favored the decrease. The share of terpenes and terpenoides and the share of aldehydes and ketones in the total volatiles increased during the post-harvest ripening. The post-harvest ripening in the dark favored the increase of the share of terpenes and terpenoides, while the ripening under daylight favored the increase of the share of aldehydes and ketones. [Projekat Ministarstva nauke Republike Srbije, br. III 46001]

Proline is one of the organic osmolytes that accumulates in plants in response to stressful environmental conditions. The aim of this study was to determine the concentration of proline in the grain filling phase in ten winter wheat cultivars under conditions of prolonged periods of air temperatures above 30?C and to assess the variability of wheat variety responses. The correlation between proline accumulation and photosynthetic pigments, accumulated starch and yield was also determined. In the experimental field, flag leaves were sampled for each variety in the grain filling phase. Statistical data analysis and parameter correlation were performed using the SPSS program. The results showed that there is a statistically significant difference between proline values in moderate and high air temperature conditions when proline accumulation occurs. The significant correlation of accumulated starch content and yield with proline concentration showed that in addition to higher proline values under heat stress, wheat varieties Apac, Talas and Futura also have higher yield and starch content. A correlation was also found between proline concentration and photosynthetic pigment contents, where the Apac wheat variety showed the best adaptive response to the investigated traits and was characterized by a smaller reduction in photosynthetic pigment content under heat stress. The interrelation of proline with the photosynthetic pigment content and wheat quality parameters may be important in breeding technologies aimed at improving wheat stress tolerance.

The objective of this study was to investigate the application of different instrumental methods for measuring the hardness of fresh and cooked parsnip. Research was carried out on two previously prepared commercial parsnip samples, both fresh and cooked for 5, 10, 15 and 20 minutes. Hardness was measured using a TA.XTPlus Texture Analyzer, equipped with different fixtures and load cells. Penetration test was performed on the parsnip discs, while the instrument was equipped with a 5 kg load cell and a 2 mm diameter stainless steel flat cylinder probe. Shearing test was conducted on the whole parsnip roots with a 30 kg load cell and Warner-Bratzler (WB) flat knife blade. The obtained values of the coefficients of variation for both methods indicated that these methods are more suitable for measuring the hardness of fresh parsnip. The results of analysis of variance showed that penetration test generally expressed better differentiation between the samples A and B. The greatest change of firmness during cooking was observed after the first 5 minutes, as measured by both methods. Parsnip firmness progressively decreased with increasing cooking time, with less pronounced differences between the cooking times obtained by shearing test. Further experiments should include more representative parsnip samples and more repetitions within the sample in order to make general conclusions. All results should be verified with sensory evaluation of parsnip hardness by an expert panel or a panel of trained assessors.

Effects of treatment with triazole fungicide were evaluated on 14 wheat genotypes with respect to mycotoxin (aflatoxins, ochratoxin A and deoxynivalenol), yield, 1000 kernel weight and hectoliter weight. Mycopopulation of seed samples was also determined. According to the results, fungicide treatment can reduce the level of mycotoxins in seed samples in order to improve the quality parameters and reduce the level of fungal contamination

Sensory analysis is the best mean to precisely describe the eating quality of fresh foods. However, it is expensive and time-consuming method which cannot be used for measuring quality properties in real time. The aim of this paper was to contribute to the study of the relationship between sensory and instrumental data, and to define a proper model for predicting sensory properties of fresh tomato through the determination of the physicochemical properties. Principal Component Analysis (PCA) was applied to the experimental data to characterize and differentiate among the observed genotypes, explaining 73.52% of the total variance, using the first three principal components. Artificial neural network (ANN) model was used for the prediction of sensory properties based on the results obtained by basic chemical and instrumental determinations. The developed ANN model predicts the sensory properties with high adequacy, with the overall coefficient of determination of 0.859.