Efikasnost ekstrakata iz hrastovog žira na usporavanje oksidacije lipida

This work investigates different extraction techniques by utilizing 95% ethanol and refined sunflower oil as well as the effects of thermal pretreatments on the extraction of antioxidants from oak acorns. Experiments were conducted using oak acorn from Quercus cerris and Quercus robur. Peroxide values measurements and TBA test were used for oxidation rate monitoring. Two types of extracts were prepared: Using dried acorns Using heat-treated acorns - 15 min 210°C. The results indicate that both oil and ethanol extracts have antioxidative properties. Heat treatment did not have adverse effect on antioxidative properties of oak acorn extract.U radu se daje prikaz različitih tehnika pripreme ekstrakata, koristeći različite rastvarače i predtretman biljnog materijala (u smislu temperature i vremena tretmana jezgra hrastovog žira kao polaznog materijala). Ispitivanja su vršena na uzorcima hrastovog žira Quercus cerris i Quercus robur. Korišćeni rastvarači su 96,5% etanol i jestivo rafinisano suncokretovo ulje. Tok oksidacije praćen je određivanjem peroksidnog broja i ekstincije TBA testom. Pripremani su ekstrakti na bazi osušenog jezgra žira kao i termički tretiran biljni materijal na temperaturi od 210°C tokom 15 minuta. Dobijeni rezultati ukazuju da i uljni i etanolni ekstrakti ispoljavaju antioksidativno dejstvo pod datim uslovima ogleda i da termički tretman jezgra ne dovodi do razgradnje antioksidacione supstance

Uticaj toplotnog tretmana na sadržaj tanina i antioksidativni efekat ekstrakta hrastovog žira quercus cerris

The results of investigation of the tannin content in the oak acorn kernel Quercus cerris, qualitative analysis of tannin and antioxidation effect of ethanol extracts of acorn on porcine lipid (prime steam lard) as a substrate are presented in this paper. Experiments were carried out on kernel samples of the domestic oak acorn, from the location Zaglavak, near by the town of Bajina Bašta. Tannin content was determined by spectrophotometric procedure using phosphorus Wolframic acid on wave length of 715 nm. Qualitative analysis of tannin included sediment and stain responses as well as tannoform test with formalaldehyde and HCl. Antioxidant effect of ethanol extracts was investigated on fat samples treated at the temperature of 600C in the dark (Schaaloven test). The rate of oxidation was determined by measuring Peroxide value (Pb) and TBA value. The investigated extracts were obtained based on drying of acorn kernel and extracts based on thermal treatment - dry frying of acorn kernel. The obtained results show that dried acorn kernel contains 11.69 % of tannin and thermally treated acorn kernel 8.55%. Qualitative analysis confirmed the presence of gallic acid (pyrogallic, hydrolysing) tannins based on positive general sediment and stain responses on tannins. Ethanol extracts demonstrate antioxidation traits on porcine lipids in trial conditions. Synergistic effect of citric acid with primary anti oxidant was not proved. Thermal treatment of acorn kernel does not reduce the antioxidation activity of extracts.U radu su prikazani rezultati ispitivanja sadržaja tanina u jezgru hrastovog žira Quercus cerris, kvalitativna analiza tanina i antioksidaciono dejstvo etanolnih ekstrakata žira na svinjsku mast (pripremljenu vlažnim postupkom) kao supstratu. Ogledi su vršeni na uzorcima jezgra hrastovog žira domaćeg porekla, sa lokaliteta Zaglavak, okolina Bajine Bašte. Sadržaj tanina određivan je spektrofotometrijskim postupkom sa fosforvolframovom kiselinom na talasnoj dužini od 715 nm. Kvalitativna analiza tanina obuhvatila je taložne i bojene reakcije kao i tanoformsku probu sa formaldehidom i HCl. Zaštitni efekat etanolnih ekstrakata ispitivan je na uzorcima masti koji su temperirani na 600C u mraku. Tok oksidacije masti praćen je određivanjem TBA vrednosti ekstincije na 532 nm i peroksidnog broja. Ispitivani ekstrakti su dobijeni na bazi osušenog jezgra žira i ekstrakata na bazi termički tretiranog - suvo prženog žira. Dobijeni rezultati pokazuju da osušeno jezgro hrastovog žira sadrži 11,69% tanina a termički tretirano 8,55%. Kvalitativnim analizama dokazano je prisustvo galnih (pirogalnih hidrolizujućih) tanina na osnovu pozitivnih opštih taložnih i bojenih reakcija na tanine. Etanolni ekstrakti ispoljavaju antioksidaciona svojstva na svinjsku mast pri uslovima ogleda, sinergistički efekat limunske kiseline sa primarnim antioksidantom nije dokazan, termički tretman jezgra hrastovog žira ne smanjuje antioksidacionu aktivnost ekstrakata

Influence of nutrition on productivity and chemical composition of khorasan wheat-triticum turgidum l. Ssp. turanicum jakubz

Khorasan wheat (Triticum turgidum L. ssp. turanicum Jakubz.) the white awn population is the optional type of a high-energy grain. This study aimed to examine the influence of plants’ mineral nutrition on the chemical composition of Khorasan grain. The mineral diet used in the supplementary plant nutrition affected the total amount of dry matter and the chemical composition of wheat grains, increasing its nutritional value. At the time of harvest, Khorasan wheat grains contained 89.74% of dry matter, i.e. 10.26% of water, while in the variants with additional nutrition had less dry matter 86.90% and more water, 13.10%, which indicates an extension of the vegetation period of plants in conditions of enhanced mineral nutrition. Mineral nutrition, which primarily increased the amount of nitrogen, statistically significantly affected protein synthesis in plants. Khorasan wheat grains had 14.94% of total proteins in the control and 15.2% in variants with NPP nutrition. Plant nutrition did not have a greater impact on the synthesis of oils in the grains, starch, NFE, and mineral salts content. The supplementary nutrition affected the total amount of dry matter and chemical composition of wheat grain increasing its nutritional value

Ekonomski efekti proizvodnje ozime pšenice na poljoprivrednim gazdinstvima u Republici Srbiji za 2006. i 2011. godinu

Based on the comparative analysis of gross margins in 2006 and 2011, the economic impact of winter wheat production on farms in the Republic of Serbia was estimated. The subject of the analysis was variable costs for purchased seed, fertilizers, pesticides, and contract harvesting services. Based on the analysis of the gross margin for winter wheat, it was noted that the value of production (VP), total variable costs (TVC) and gross margin (GM) were significantly higher in 2011 than in 2006. In 2011, VP was higher due to a significantly higher yield and the higher price of winter wheat grain. In addition to higher prices of all inputs, the increase in variable costs was mostly influenced by the higher price of fertilizer. Comparing the two time periods in winter wheat production, it was concluded that the value of GM in 2011 increased by 30%.Na osnovu uporedne analize vrednosti bruto marži u 2006. i 2011. godini procenjen je ekonomski efekat proizvodnje ozime pšenice na poljoprivrednim gazdinstvima u Srbiji. Analizirani su varijabilni troškovi, koji su se odnosili na utrošak novčanih sredstava za nabavku semena, đubriva, pesticida i ugovorene usluge za žetvu. Na osnovu analize kalkulacija bruto marži za ozimu pšenicu konstatovano je da su u odnosu na 2006. vrednost proizvodnje (VP), ukupni varijabilni troškovi (UVT) i bruto marža (BM) bili značajno veći u 2011. godini. U 2011. godini veća VP uslovljena je značajno većim prinosom i višom cenom zrna ozime pšenice. Na povećanje varijabilnih troškova, pored viših cena svih inputa, u najvećoj meri uticala je cena đubriva. Poređenjem ova dva vremenska perioda u proizvodnji ozime pšenice, vrednost BM u 2011. godini bila je veća za 30%

Mogućnosti primene alternativnog načina poljoprivredne proizvodnje u Srbiji

As reaction to distinct negative effect of modern agricultural technology and techniques on preservation and protection of environment, lately research of alternative methods of efficient agricultural production in conditions of necessary ecological limits is intensified. The term alternative, biological, ecological or organic agriculture are often determined as systems and methods of plant and livestock production which are in collision with system of ordinary agriculture. Alternative agriculture represents production system which avoids or considerably excludes the application of synthetic mineral fertilizers, pesticides growth regulators and food additives. For control and management of product quality ISO 9000 standards were adopted, and for management of quality of environment is determined by standards ISO 14000. Main purpose of legislatory regulations is protection of health of the population and biodiversity. Standards and regulations on protection of environment valid in EU will be applied on the territory of member states. They will directly or indirectly be transferred through various market mechanisms to wide European area. Adjustment of Serbian economy includes harmonization with the EU policy on protection of the environment which will enhance the competitiveness of Serbian economy on European and world market.Kao reakcija na izraženo negativno dejstvo savremene poljoprivredne tehnologije i tehnike na održanje i zaštitu životne sredine u poslednje vreme se intenziviraju istraživanja alternativnih načina ekonomski efikasnog obavljanja poljoprivredne proizvodnje u uslovima neophodnih ekoloških ograničenja. Pojam alternativna, biološka, ekološka ili organska poljoprivreda često su označeni kao sistemi i načini obavljanja biljne i stočarske proizvodnje koji su u koliziji sa sistemom već uobičajene poljoprivrede. Alternativna poljoprivreda predstavlja sistem proizvodnje koji izbegava ili znatno isključuje primenu sintetičkih mineralnih đubriva. pesticida, regulatora rasta i aditiva u hrani. Za upravljanje kvalitetom proizvoda usvojeni su standardi ISO 9000, a upravljanje kvalitetom životne sredine planirano je standardima ISO 14000. Osnovna svrha zakonodavne regulative je zaštita zdravlja populacije i biodiverziteta. Standardi i pravila zaštite životne sredine EU primenjivati će se na prostoru zemalja članica. Oni će direktno i indirektno tržišnim mehanizmima biti preneti na širok evropski prostor. Prilagođavanje srpske privrede podrazumeva usaglašavanje sa politikom zaštite životne sredine EU, što će pojačati konkurentnost privrede Srbije na evropskom i svetskom tržištu

Agroekološki uslovi i morfološko-produktivna svojstva krupnika

Experiments were conducted during 2011-2012, at three localities in Serbia (Valjevo, Nova Varoš and Nova Pazova). The seed of spelt wheat cultivar Nirvana was used, having been selected at the Institute of Field and Vegetable Crops in Novi Sad. The objective of the research was to assess the effect of agro-ecological conditions on morphological and productive properties of spelt wheat grown on different types of soils. The effect of the locality was significantly expressed in all tested morphological properties of spelt wheat (plant height, number of spikelets, number of grains per spikelet), while meteorological conditions (year) affected spike length and grain mass per spike significantly. The average grain yield from all three localities was 3.20 t ha-1. A considerably higher yield was achieved on chernozem, locality Nova Pazova (3.89 t ha-1). The comparison of the grain yields from Valjevo (eutric cambisol) and Nova Varoš (grey forest soil) did not show any significant differences.Ispitivanja su sprovedena tokom 2011-2012 godine, na tri lokaliteta u Srbiji (Valjevo, Nova Varoš i Nova Pazova). Korišćeno je seme krupnika sorte Nirvana, selekcionisana u Institutu za ratarstvo i povrtarstvo, Novi Sad. Cilj istraživanja je bio da se oceni uticaj agroekoloških uslova na morfološke i produktivne osobine pod različitim tipovima plodnosti zemljišta. Uticaj lokaliteta značajno se ispoljio kod svih ispitivanih morfoloških osobina krupnika (visina biljke, broj klasića, broj zrna u klasiću), a meteorološki uslovi (godina) su značajno uticali na dužinu klasa i masu zrna u klasu. Prosečan prinos zrna krupnika na sva tri lokaliteta iznosio je 3,20 t ha-1. Značajno veći prinos ostvaren je na černozemu, lokalitet Nova Pazova (3,89 t ha-1). Poređenjem prinosa zrna na lokalitetima Valjevo (gajnjača) i Nova Varoš (sivo šumsko zemljište) nisu utvrđene značajne razlike

Kvalitet i stanje semena pšenice (Triticum spp.) tokom skladištenja

The effect of storage on quality and condition of grain of three wheat cultivars (Ljiljana, Dragana and Simonida) selected in Serbia, was studied. Freshly harvested wheat was stored at 25°C for 12 and 20 months. Decreasing of the volume from 812.3 to 727.7 kgm-3 and absolute mass from 38.5 to 33.0% of wheat grain during storage was recorded. Grain germination in interaction of storage duration and temperature remained at the level above 95%. The interaction of studied factors exhibited no statistically significant effect on the changes in the degree of germination of wheat grain. The changes of the acid degree value (2.0- 2.4 ml 1(NaO)/100 g) were at the level of statistical significance. pH value of fresh samples of grain was 6.5 and after 20 months 5.5. The samples tested from the aspect of their glassiness were homogenous, the value of the coefficient of variation for storage duration was CV lt 10%, and for genotypes CV lt 18%. The storage duration of wheat grain mostly contributed to the increase of the acid degree value, and slightly less the genotype, as well as the interaction of these factors.Ispitivan je uticaj skladištenja na kvalitet i stanje semena pšenice za tri sorte (Ljiljana, Dragana i Simonida) koje su selekcionisane u Srbiji. Posle žetve pšenica je uskladištena na 25°C za 12 i 20 meseci. Zabeležen je pad vrednosti zapreminske 812,3-727,7 kgm-3 i apsolutne mase 38,5 - 33,0% tokom skladištenja semena pšenice. Klijavost semena u interakciji vremena i temperature skladištenja se zadržala na nivou preko 95%. Interakcija ispitivanih faktora nije ispoljila statistički značajan uticaj na promenu stepena klijavosti semena pšenice. Promene kiselinskog stepena (2,0-2,4 ml 1(NaO)/100 g) su na nivou statističke značajnosti. pH vrednost svežih uzoraka semena je bila 6,5 a nakon 20 meseci 5,5. Uzorci testirani na svojstvo staklavosti su veoma homogeni, vrednost koeficijenata varijabilnosti za dužinu skladištenja je Cv lt 10%, a za genotipove Cv lt 18%. Dužina skladištenja semena pšenice najviše doprinosi porastu vrednosti kiselinskog stepena, a nešto manje genotip, kao i interakcija ovih faktora

Khorasan wheat population researching (triticum turgidum, ssp turanicum (mckey) in the minimum tillage conditions

Khorasan wheat occupies a special place in the group of new-old cereals (Triticum turgidum, ssp. Turanicum McKey). It is an ancient species, native to eastern Persia, that is very close to durum wheat by morphological characteristics. Investigations were carried out in agro ecological conditions of the eastern Srem, with two wheat populations with dark and bright awns as objects of study. The following morphological and productive characteristics were investigated: plant height (PH), spike length (SH), number of spikelets per spike (NSS), absolute weight (AW) and grain weight per spike (GW), seed germination (G) and grains yield (YG). Field micro-experiments were set on the carbonate chernozem soil type on loess plateau in 2011 and 2012. Hand wheat sowing was conducted in early March with drill row spacing of 12 cm. The experiment was established as complete randomized block system with four replications. Tending crops measures were not applied during the growing season. Plants were grown without usage of NPK mineral nutrients. Chemical crop protection measures were not applied, although powdery mildew (Erysiphe graminis) was appeared before plants spike formation in a small extent. The results showed that both populations have a genetic yield potential. In general, both populations manifested a satisfactory tolerance on lodging and there was no seed dispersal. Plants from bright awns population were higher, had longer spikes and larger number of spikelet's per spike. However, plants from dark awns population had higher absolute weight and grains weight per spike, as well as grain yield per plant. Strong correlation connections were identified among the investigated characteristics. The determination of correlations, as well as direct and indirect affects, enabled easier understanding of the mutual relationships and their balancing in order to improve the yield per unit area

EFFECT OF TEMPERATURE ON THE PHYSICAL CHANGES AND DRYING KINETICS IN PLUM (Prunus domestica L.) POŽEGAČA VARIETY

In this study, drying kinetics of autochthonous variety Požegača plum was examined in a laboratory dryer at three temperatures. The whole plum fruits, together with the kernels were subjected to the drying process. The effect of drying has been examined at temperatures of 55, 60 and 75 °C, with a constant air velocity of 1.1 m s-1. The corresponding experimental results were tested using six nonlinear regression models. Coefficient of determination (R2), standard regression error (SSE), model correlation coeficient (Vy), as well as the maximum absolute error (ΔY) showed that the logaritmic model was in good agreement with the experimental data obtained. During drying of plums, the effective diffusivity was found to be between 5.6×10-9 for 55 °C and 8.9×10-9 m2s-1 at 75 °C, respectively. The physical characteristics of fresh (length 39.64 mm and width 29.15 mm) and dried (length 37.52 mm and width 22.85 mm) plum fruit were determined. Finally, by chemical analysis, the contents of micro-and macro-elements (Fe, Mn, Cu, B and N, F, K, Ca, Mg and S) in the skin and flesh of the dried product, prunes, has been established

Productivity traits of rye (secale cereale), khorasan wheat (triticum turgidum, ssp taranicum mckey) and quinoa (chenopodium quinoa willd) grown on degraded soil

The productivity traits of rye, khorasan wheat and quinoa on degraded soil were investigated in a three-year research (2010-2012). The research was carried out in two localities: Stanari (ST) (Bosnia-Herzegovina) and at "TENT 2" in Obrenovac (OB) (Serbia). A significant interdependence between grain yield and aboveground biomass yield was observed in the investigated genotypes and localities. The resulting average grain yields in these localities ranged between 1,166-1,702 kg ha-1 (rye), 1,826-1,943 kg ha-1 (khorasan wheat) and 520-966 kg ha-1 (quinoa). Fluctuations in grain yields were due to different soil conditions different nutrient contents and the distribution of precipitation at initial stages of crop development. This research confirmed that rye is a crop with minimum soil requirements and it can be successfully grown in poor soil. The second best biomass yield was obtained by khorasan wheat, while the lowest biomass yield was obtained by quinoa