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Amino acid profile of four honey types - two monofloral (acacia and sunflower), one polyfloral (meadow honey) and forest honey (honeydew honey) collected from the Autonomous Province of Vojvodina (Republic of Serbia) was determined using ion exchange chromatography. The results showed that proline was the dominant amino acid in all analyzed samples. Other amino acids present in substantial amounts were glutamic acid ˃ phenylalanine ˃ glycine ˃ serine in acacia and meadow honey samples, while sunflower was characterized by the presence of higher content of alanine compared to serine. Forest honey samples possessed the highest proline content and also the highest total amino acid content. Based on the amino acid contents, honey samples were classified using chemometric methods (cluster analysis (CA) and principal component analysis (PCA)). CA of different honey types could be applied to group honey types. According to the PCA, honey samples are clearly distinguished and form the specific groups. Therefore, amino acid profile could give an indication of honey botanical origin.

The formation of pyrazine cation radicals was detected in model systems consisted of D- (+)-glucose (1.0 mol L-1) and structural isomers of aminobutanoic acid (1.0 mol L-1) heated at the temperature of 98 °C for 20 minutes using electron spin resonance (ESR) spectrometry. Based on the analyses of hyperfine structure of ESR spectra of reaction mixtures of model systems, the presence of 1,4-disubstituted pyrazine cation radicals was found. Different polyphenols (gallic, caffeic, ferulic, chlorogenic acid, and tannic acid) were added in the model systems to investigate their influence on the formation of pyrazine cation radicals. It was found that tannic acid was the most efficient in inhibiting the formation of free radicals followed by gallic > caffeic ( chlorogenic > ferulic acid.

The aim of this work was to investigate nutritional profile in relation to proteins, amino acids, fatty acids and mineral composition, as well as phenolic profile of small edible fungal species Coprinellus disseminatus originated from Serbia. Total protein content in the analyzed fungal species was 9.72%. Fifteen protein fractions obtained by electrophoresis were identified in a range from 1.6 to 63.6 kDa. Chip-based separations showed the presence of protein fraction with molecular weight of 27.5 kDa that could possess antifungal activity. The total essential and non-essential amino acid contents were 29.57 and 96.69 mg/g DW, respectively. Among the essential amino acids, leucine was the most abundant. Fatty acid composition of C. disseminatus showed that polyunsaturated fatty acids (PUFA, 59.1% of total FA) predominated over saturated fatty acids (SFA, 23.1% of total FA) and monounsaturated fatty acids (MUFA, 17.9% of total FA). The dominant fatty acids were linoleic acid (56.6%), palmitic acid (13.9%), and oleic acid (12.0%). The most abundant macroelement in C. disseminatus was potassium, followed by calcium and magnesium, while iron dominated in microelements. Eight phenolic compounds were quantified in methanolic extract of C. disseminatus by LC-MS/MS with the highest amount of p-hydroxybenzoic acid and p-coumaric acid reaching 9.46 ± 0.2 µg/g DW and 7.8 ± 0.1 µg/g DW, respectively.

Novel vegetable proteins, like those extracted from abundant raw materials (grass) or agri-food by-products and waste streams (oilseed meals), are expected to be used as replacers for animal-derived proteins, due to higher production efficiency, reduced life cycle environmental impact and possibility to meet consumers' dietary or cultural preferences. Although having a versatile functionality (emulsifying, foaming, gelling, texturizing agents), application of proteins is limited since their properties highly depend on their structure and composition, environmental factors (pH, ionic strength, presence of other micro- and macro-molecules in food matrices) and isolation method and conditions. The objective of this article is to review the current techniques used to isolate the proteins from vegetable raw materials and comment on the influence of extraction method and conditions (pH, ionic strength, extraction media temperature, extraction time, etc.) on protein properties (yield, purity, appearance, solubility, denaturation degree, emulsification efficiency, etc.). The utilization of novel technologies such as ultrasound assisted extraction, electro-activation technique and approaches (enzyme-assisted extraction) to improve protein extraction yield or functionality was also discussed.

Different types of instant porridges have become a popular choice for breakfast, and it is known that breakfast is an important meal for daily appetite control. On our market there is porridge of uniform composition based on cereals, primarily oats. However, high-protein porridge is not available, which is a significant deficiency in the assortment of these products. In addition, insufficient intake of quality protein remains a dietary problem, particularly among children and the elderly, where diets consist mainly of cereals. Plant proteins in combination with cereals could be used to produce high protein instant porridge. In this study, proteins from legumes such as soybean and pea, specifically soy protein concentrate, soy protein isolate, and pea protein isolate were applied. Protein preparations were added to the main mixture composed of the buckwheat and corn extrudate and other additional ingredients. The protein preparations were added at three different levels: soy protein concentrate at 0, 7.5 and 15% (w/w main mixture basis) and soy protein isolate and pea protein isolate at 0, 15 and 30% (w/w main mixture bases), with the objective of optimizing the composition of the high-protein instant porridge. The aim of optimization was to maximize the protein content and overall acceptability. The optimal doses of protein preparations were determined using the method of desirability function and it was found that the optimized dose for the soy protein concentrate was 1.43 g/100 g, soy protein isolate 21.07 g/100 g and pea protein isolate 14.83 g/100 g. The prediction value for protein content was 24.77 %/DM and overall acceptability 4.09. The obtained experimental values were close to the prediction values: 24.32 %/DM for protein content and 4.41 for overall acceptability. The protein content of the formulated porridge was 24.32 %/DM, which is more than twice as high as that in the oat porridge present on the market. Based on standard nutritional values, the newly formulated high-protein instant porridge could be recommended as appropriate breakfast meal for adults.

Buckwheat is grown primarily because of its grain which, after undergoing the processes of dehulling, grinding and sieving, is used to produce buckwheat flour which is characterized by a considerable content of antioxidants, especially polyphenols and tocopherols. Buckwheat polyphenols are represented by phenolic acids and flavonoids, mainly rutin, a proven potent antioxidant. The content of polyphenols and tocopherols in buckwheat grain primarily depends on the buckwheat species, growing area, climate and growing conditions. Common buckwheat (Fagopyrum esculentum Möench), which is often used for the production of light and wholegrain buckwheat flour, contains less polyphenols than tartary buckwheat. The content of polyphenols in common buckwheat grain varies depending on the grain part. As their largest amount is contained in the hull and the outer layers of the grain, the wholegrain buckwheat flour is superior in polyphenols than the light buckwheat flour. Therefore, the wholegrain buckwheat flour is characterized by a higher antioxidant capacity. Polyphenols in buckwheat flour exist in free and bound forms, where the contribution of free polyphenols ranges between 48-64%. Due to a relatively high content of antioxidants in light and wholegrain buckwheat flour, they are used for substitution of wheat or other cereal flours in bakery, pasta and confectionary formulations in order to create either added value or gluten-free products. The aim of a long-term consumption of buckwheat flours is to achieve health benefits and protect from many chronic diseases. Technological procedures and some treatments used during the food preparation influence polyphenol composition and content and consequently the functionality of food. Therefore, in order to minimize polyphenol losses and preserve the antioxidant capacity of the final products it is necessary to understand the thermal treatments and their mechanisms. [Projekat Ministarstva nauke Republike Srbije, br. TR 31029]

Quality parameters and the possibility of successful placement of buckwheat-enriched wheat bread on the national market are presented in this paper. Analysis of the market position of buckwheat-enriched wheat bread includes demands, offer and competition. Elements that affect the overall retail price of buckwheat-enriched wheat bread are given in details, along with SWOT analysis and marketing plan including target market, market supply and product marketing mix. According to all performed analyses it could be concluded that this product should be positioned on the national market, especially for people with special needs and requirements.

Blueberry pomace, by-product of juice production, was processed into a new food ingredient by drying and grinding and used for a new gluten-free cookies' formulation, with the aim of improving nutritional profile and antioxidant capacity. Since duration and temperature at which dough is thermally treated during baking highly influence the quality of a baked product, the objective of this work was to optimise the baking conditions in order to obtain the best technological quality of the cookies. Referring to the results obtained at 160 and 170 °C and different baking times, the following was found: the difference in baking conditions caused variation between cookies' diameters of less than 1%, more regular shape of the cookies was obtained when baking time was shorter, hardness of cookies is highly correlated with moisture content, water activity, baking loss and short/long diameter ratio values. The colour characteristics (L*, a* and b*) of cookies' top and bottom surfaces indicated that the cookies were not overbaked under the chosen baking conditions. Baking time of 14 min at 170°C was found to be the optimal baking conditions for the blueberry pomace enriched gluten-free cookies.

Growing demand for better quality and cheaper products put on the need to industry to balance between the two kinds of needs, which are the reduction of production costs and to ensure a high quality product. This is the case with dried sugar beet pulp as a byproduct of sugar refining process. One of the possibilities to reduce energy consumption is savings in the process of thermal dehydration in the process of the conventional drying of pulp. Pulp drying is one third of total energy consumption in the sugar factory. Acidification of water extraction result in pulp that could be pressed better and in other hand in the juice with less non-sucrose compounds. Keeping the extraction process under certain conditions, directly affects on the quality of the extracted pulp and on effects of their further processing. This paper examines the impact of the extraction parameters of sugar from sugar beet and agents of acidification for water extraction (sulphurous acid, hydrogen peroxide) on the quality of dried sugar beet pulp. Extraction of sugar from sugar beet cossettes by hydrogen peroxide at pH 5.5 to 8.5 does not cause changes in mechanical properties of sugar beet cossettes and in water retention coefficient, but increases the brightness of dried sugar beet pulp for about 5-7 units, which solubility in water does not depend on the applied concentration of extracting agents, but increases in dependence on the duration of the extraction. Sugar beet pulp extracted at pH 11.0 has reduced strength, they are highly hydrated, and under the force they lose their shape, binding a larger amount of water thus reducing the effect of their pressing. The changes in microstructure were probably accompanied by segmenting the linear parts of macromolecules and are reflected in the increase of water retention capacity and increase the solubility of dried sugar beet pulp for two to three times. Under the same conditions of extraction, sulphurous acid produces similar but relatively mild changes in the characteristics of extracted and dried sugar beet pulp compared to conditions when hydrogen peroxide is used. From the point of the quality of the product of extraction, the most favorable results are obtained when the extraction is carried on at pH 5.5 for a period of 1 h at 70 °C, using water for extraction with sulphourus acid with the addition of 5% hydrogen peroxide. Under these conditions no significant degradation of sugar beet tissue is detected, do not change the physical, chemical and mechanical properties of the extracted pulp. But there is an average increase of lightness of dried noodles for about 7 units, which represents a significant improvement of their quality, since there is difficult to sell on the market the dried sugar beet pulp with increased colour.

Among a number of laboratory methods used to estimate the adequacy of heat treatment applied to full-fat soybean (FFSB) protein solubility in potassium hydroxide (PSKOH) is an unofficial method, but it is used by many laboratories due to its simplicity. It has been reported that the results of PSKOH analysis of the same sample of FFSB on the degree of heat treatment vary widely between laboratories. In this study, the original PSKOH method has been modified and subjected to an inter-laboratory test, with participation of 9 laboratories. Eight FFBS samples were processed by dry extrusion at temperatures ranging from 110 to 164°C and analysed on PSKOH. Processed FFSB samples were also assessed in a growth trial with broilers. Analysis of FFSB by the PSKOH method generated for adequately-processed FFSB values between 67.1 and 76.5%. The values above 76.5% corresponded to under-processed and below 67.1% to over-processed FFSB. The PSKOH method generated good precision, i.e. the repeatability and reproducibility limits of 3.48 and 10.86 %, respectively. The modified PSKOH method can be recommended as a reliable indicator for quality control of heat processed FFSB for the use in routine laboratory practice. This study could pave the way for establishing PSKOH as an official method for determining the nutritional value of FFSB following heat treatment.

Antioxidative activities of wheat flours (type 500 and wholegrain) and buckwheat flours (light and wholegrain) were tested using 1,1-diphenyl-2-picrylhydrazyl (DPPH·)-scavenging activity, reducing power and chelating activity on Fe2+. Also, the content of the total phenolics of ethanolic extracts was estimated. Polyphenolics content (expressed as gallic acid equivalent, GAE) in wheat flours varied between 37.1 and 137.2 μg GAE/g extract, while its content in buckwheat flour were at least four time higher and ranged between 476.3 and 618.9μg GAE/g extract. Ethanolic extracts of buckwheat flours exhibited higher antioxidant activities in all the assays, except for chelating activity. Regarding all the obtained results, it can be concluded that bakery products produced with buckwheat flour could be regarded as potential functional foods.

An inhibitory effect of various concentrations (0.0, 0.5, 1.0, 1.5 and 2,0%) of mint (Mentha piperita L.) and caraway (Carvum carvi L.) on the growth of A. fumigatus, A. flavus and A. ochraceus was examined during 10 days of cultivation in YES medium at temperature of 25°C. Mint showed stronger inhibitory effect than caraway. Total dry weight (g/l) after 10 days of the growth of A. fumigatus in YES medium with 0.5% of mint decreased by about 95%, A. flavus by 97% and A. ochraceus by about 82%. Addition of higher concentrations of mint (1.0, 1.5 and 2.0%) reduced the growth of all tested species. It was poor and hardly visible. pH values of the media increased with the increase of mint concentrations. A. fumigatus showed the highest sensitivity towards caraway and A. flavus the lowest. Total dry weight (g/l) after 10 days of growth of A. fumigatus in medium with 0.5% of caraway decreased by about 72% in comparison to the control. In media with higher concentrations of caraway, its growth was found to be very poor. Concentration of 1.0% of caraway reduced A. flavus growth by 15% and of 1.5% by 92%, in regard to the control. In medium with 2.0% of caraway the growth of A. flavus was observed as poor and hardly visible. The growth of A. ochraceus in medium with 0.5% of caraway decreased by about 85% comparing with control and further decrease was noticed by the increase of concentrations. In medium with 1.5% of caraway a reduction of about 95% of growth was found and under 2.0% of caraway it was poor. pH of the media also increased with the increase of caraway concentrations. Applied concentrations of mint and caraway inhibited completely the production of AB1 by A. flavus.

The ethanolic extract of sugar beet pulp at 100% exibited good antioxidant activity of 69.74%. It showed an excellent scavenging activity on 1,1-diphenyl-2-picrylhydrazyl radicals (84.94%) and was a mild chelator for ferrous and cupric ions. On the basis of some identified phenolic acids in ethanolic extract from sugar beet pulp it is concluded that predominant acids (ferulic, gentisic and p-coumaric acid), which have been previously evidented as relatively potent antioxidants, contribute to the antioxidant properties of the investigated extract. Antioxidative nature of ethanolic extract from sugar beet pulp, that is sugar beet pulp itself, indicate that it could be used as antioxidative component for decreasing oxidative changes in foods.

Copyright of Chemical Industry / Hemijska Industrija is the property of Association of Chemical Engineers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chemical Industry / Hemijska Industrija is the property of Association of Chemical Engineers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Antioxidative activities of wheat flours (type 500 and wholegrain) and buckwheat flours (light and wholegrain) were tested using 1,1-diphenyl-2-picrylhydrazyl (DPPH.)-scavenging activity, reducing power and chelating activity on Fe2+. Also, the content of the total phenolics of ethanolic extracts was estimated. Polyphenolics content (expressed as gallic acid equivalent, GAE) in wheat flours varied between 37.1 and 137.2 µg GAE/g extract, while its content in buckwheat flour were at least four time higher and ranged between 476.3 and 618.9 µg GAE/g extract. Ethanolic extracts of buckwheat flours exhibited higher antioxidant activities in all the assays, except for chelating activity. Regarding all the obtained results, it can be concluded that bakery products produced with buckwheat flour could be regarded as potential functional foods. [ABSTRACT FROM AUTHOR]