Protein profiles and total antioxidant capacity of water soluble and insoluble protein fractions of white cow cheese at different stage of ripening

This research is focused on proteolysis and total antioxidant capacity of proteins of white brined cheese prepared from overheated (90 degrees C, 10 minutes) cow milk. White brined cow cheese of overheated milk went through specific proteolytic changes during ripening that were result of high level of whey proteins incorporated into the gel matrix. Specificity was reflected through the relatively low level of soluble nitrogen fractions, the intensive and continual decrease of alpha(s)-caseins up to 15.42 % of initial content, slow degradation of beta-casein throughout the whole ripening period and high level of proteolytic products tightly bounded into gel matrix. Strong negative correlations (-0.97, -0.98 and -0.91; p lt 0.05) between ripening time and resudual alpha(s)-caseins, beta-casein and low molecular weight products were observed. Proteolysis also affected the total antioxidant capacity of both water soluble and water insoluble nitrogen fractions, but to different extents and with different trends. Total antioxidant capacity of water insoluble fraction increased slowly during the whole ripening period, wherease significant improvement of total antioxidant capacity of water soluble fraction started after 30 days of ripening. These findings could be useful for better understanding and control of the white brined cow cheese production

Characterization of sunflower seed and kernel proteins

Total sunflower proteins, storage proteins, and helianthinin (11S) and 2S albumin fractions and their respective subunits in seeds and kernels of three sunflower hybrids were analyzed. Protein contents were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and coupled with densitometry. The SDS-PAGE profiles of the seed and kernel proteins in the crude extracts for all genotypes showed a very similar number of protein bands (thirty two) in the electrophoretograms. Three polypeptide groups of helianthinin fraction were detected. Two of these were acidic (α, Mw = 36,800 - 42,900 Da and α', Mw = 31,000 - 35,300 Da), while one was basic (β, Mw=21,000 - 29,600 Da). The molecular weight of the 2S albumin proteins ranged from 11,500 to 20,100 Da. According to our results, there were significant differences among the seed and kernel protein contents. The 2S albumin content was significantly higher in kernels than in whole seeds of sunflower hybrids (P lt 0.05). By contrast, the 11S helianthinin content was significantly higher in seeds (where it ranged from 61.75 to 67.70% of totally extracted proteins) than in kernels (varied from 57.36 to 61.51% of totally extracted proteins) of sunflower hybrids (P lt 0.05)

Expected genetic advance and stability of phytic acid and antioxidants content in bread and durum wheat

Fifteen genotypes of bread wheat (Triticum aestivum L.) and fifteen genotypes of durum wheat (Triticum durum Desf.) were evaluated in the multi-environment trial during 2010-11. and 2011-12 vegetation seasons to investigate components of variance, heritability in a broad sense (h(2)), expected genetic advance (GA), and stability of phytic acid (PA), inorganic phosphorus (P-i), phytic phosphorus (P-p)/P-i relation, yellow pigment (YP), water soluble phenolics (WSPH) and free protein sulfhydryl groups (PSH) content. The field trials were carried out at three locations in Serbia, as randomized complete block design with four replications. The genetic component of variance (sigma(2)(g)) predominated the genotype x environment interaction (sigma(2)(ge)) component for: P-i in bread wheat (3.0 times higher), P-p/P-i in bread wheat (2.1 times higher) and in durum wheat (1.2 times higher), YP content in bread wheat (2.2 times higher) and in durum wheat (1.7 times higher), and WSPH content in bread wheat (1.4 times higher). The relation sigma(2)(g)/sigma(2)(ge) for P-i content in durum wheat was equal to one. The sigma(2)(ge) prevailed sigma(2)(g) for: PA in bread wheat (1.7 times higher) and in durum wheat (5.7 times higher), PSH in durum wheat (3.7 times higher), and WSPH in durum wheat (5.2 times higher). High h(2) coupled with high expected genetic advance as percent of mean (GAM) were observed for: P-i (93.7% and 26.1%, respectively) in bread wheat, P-p/P-i relation in bread wheat (92.4% and 20.7%, respectively) and in durum wheat (87.2% and 20.8%, respectively), YP content in bread wheat (92.6% and 28.0%, respectively) and in durum wheat (90.7% and 28.1%, respectively), and WSPH content (88.9% and 25.8%, respectively) in bread wheat. PA content in bread and durum wheat had medium to medium high h(2) (50.5% and 77.9%, respectively), and low expected GAM (9.9% and 3.7%, respectively). GGE biplots with average-environment coordination (AEC) indicated less stability of durum wheat for PA, WSPH and PSH content

Poređenje sitnozrnih žitarica prema sadržaju dijetalnih vlakana i proteina

The content of dietary fibres (cellulose, hemicellulose, lignin, NDF, ADF), tryptophan and proteins, as well as their quality index were determined in whole grains of bread and durum wheat, rye, hull-less barley and hull-less oat, each represented with four genotypes. In addition, content of β-glucans in hull-less barley were determined. In average, hull-less barley and oat had the lowest content of hemicellulose (22.54 and 13.11% d.m., respectively), cellulose (1.36 and 1.41% d.m., respectively), lignin (0.98 and 0.49% d.m., respectively), as well as NDF (24.84 and 15.16% d.m., respectively) and ADF (2.30 and 2.04% d.m., respectively). In average, the highest content of hemicellulose was in durum wheat (33.47% d.m.), followed by rye (29.63% d.m.), and bread wheat (23.24% d.m.). Among tested hull-less barley genotypes the the content of β-glucans ranged from 4.1% d.m. (IWHBON 97-18) to 5.6% d.m. (Apolon). The highest content of proteins (on average 15.65% d.m.) and tryptophan (on average 0.206% d.m.) was in hull-less oat. Hull-less barley had the highest protein quality index (1.48%) followed by bread and durum wheat and hull-less oat (IQ 1.35, 1.34 and 1.31%, respectively), and rye (IQ 0.93%). The results indicate that there is genetic diversity in content of dietary fibres and proteins among tested genotypes and that it should be possible to selectively breed for lines with high nutrition capacities, as well as, to improved diet requirements.U zrnu genotipova hlebne i durum pšenice, raži, golozrnog ječma i golozrnog ovsa određen je sadžaj dijetalnih vlakana (celuloze, hemiceluloze, lignina, NDF-a, ADF- a), triptofana i proteina, kao i njihov indeks kvaliteta. Pored toga određen je i sadržaj β-glukana u zrnu četiri reprezentativna genotipa golozrnog ječma. U proseku, golozrni ječam i ovas imali su najniži sadržaj hemiceluloze (22.54 i 13.11% s.m.), celuloze (1.36 i 1.41% s.m.), lignina (0.98 i 0.49% s.m.), kao i NDF (24.84 i 15.16% s.m.) i ADF (2.30 i 2.04% s.m.). Najviši sadržaj hemiceluloze bio je u zrnu durum šenice (u proseku 33.47% s.m.), sledi raž (u proseku 29.63% s.m.) i hlebna pšenica (u proseku 23.24% s.m.). U zrnu ispitivanih genotipovima golozrnog ječma sadržaj β-glukana se kretao od 4.1% d.m. (IWHBON 97-18) do 5.6% d.m. (Apolon). Najviši sadržaj proteina (u proseku 15.65% d.m.) i triptofana (u proseku 0.206% d.m.) bio je u zrnu golozrnog ovsa. Najviši indeks kvaliteta proteina bio je u zrnu golozrnog ječma (u proseku 1.48%), sledi hlebna i durum pšenica i golozrni ovas (1.35, 1.34 i 1.31%), a zatim raž (0.93%). Rezultati ukazuju na genetičku divergentnost u sadržaju dijetalnih vlakana i proteina između ispitivanih genotipova i mogućnost odabira genotipova za selekcione linija visokog nutritivnog kapaciteta, kao za i poboljšane zahteva ishrane

Genetička varijabilnost sadržaja albumina i globulina i aktivnosti lipoksigenaze i peroksidaze između genotipova hlebne i durum pšenice

The classical Osborne wheat proteins fraction (albumin-globulin), as well as several polypeptides from the non-gluten protein fraction using SDS-PAGE analyses were determined in the grain of five bread (T. aestivum L.) and five durum wheat (T. durum Desf.) genotypes. In addition, the activity rate of lipoxygenase (LOX) and peroxidase (POD) enzymes implicated in the antioxidant metabolism was determined. Albumins and globulins in wheat grains were characterized by rich protein pattern - the number of bands varied from 19 to 23 and they were defined by molecular weight 76.4-12.4 kDa. The great differences between bread and durum wheat polypeptide contents were found. Result pointed out that polypeptides with molecular weight of 65.6, 43.5 and 32.9 kDa could be used to differentiate the bread from durum wheat. Significant differences in the LOX and POD activity between and within two wheat species were detected. Present study showed in durum wheat a lower activities of LOX and POD enzymes for about 45 and 22%, respectively, than in bread wheat. Our results could be useful for plant breeders in screening and selecting of better raw materials with high protein quality for the flour, breadmaking and pasta industry.Određen je sadržaj albuminsko-globulinske frakcije, kao i polipetida koji ulaze u sastav ovih neglutenskih proteina korišćenjem SDS-PAGE analize u zrnu pet genotipova hlebne pšenice (T. aestivum L.) i pet genotipova durum pšenice(T. durum Desf.). Pored toga, određena je aktivnost oksidativnih enzima, lipoksigenaze (LOX) i peroksidaze (POD), koji su uključeni u metabolizam antioksidanasa.Albumisko- globulinska frakcija proteina zrna pšenice karakterisala se bogatom proteinskom šemom - broj traka na gelu je varirao od 19 do 23, a molekulska masa izolovanih proteina kretala se od 76.4 do 12.4 kDa. Detektovani polipeptidi u zrnu genotipova hlebne i durum pšenice razlikovali se u sadržaju. Rezultati ukazuju da bi se polipeptidi molekulskih masa 65.6, 43.5 i 32.9 kDa mogli koristiti za razlikovanje hlebne i durum pšenice. Između i unutar analiziranih vrsta pšenice detektovana je značajna razlika u aktivnosti enzima LOX i POD. Rezultati pokazuju nižu aktivnost LOX i POD u zrnu durum pšenice za 45, odnosno 22% u odnosu na hlebnu pšenicu.Dobijeni rezultati mogu doprineti selekciji osnovnog materijala visokog kvaliteta proteina za upotrebu u pekarstvu i industriji testenina

The Influence of Milk Type on the Proteolysis and Antioxidant Capacity of White-Brined Cheese Manufactured from High-Heat-Treated Milk Pretreated with Chymosin

We investigated the effect of milk type on the proteolysis and total antioxidant capacity (TEAC) of white-brined cheeses prepared from high-heat-treated (90 degrees C, 10 min) cow's and goat's milk, pretreated with chymosin at a low temperature (4 degrees C). The cheeses produced showed improved antioxidant characteristics and a high content of denatured whey proteins. However, these characteristics depend on the type of milk and the ripening time. Ripened cow's milk cheese had higher values of WSN/TN (water-soluble nitrogen per total nitrogen content) and TCA-SN/TN (nitrogen soluble in 12% trichloroacetic acid per total nitrogen), but similar PTA-SN/TN (nitrogen soluble in 5% phosphotungstic acid per total nitrogen) values were observed in ripened cheeses. The antioxidant potential of a WSF (water-soluble fraction) was higher in goat's milk cheese, but higher TEAC (total antioxidant capacity) values of WINF (water-insoluble fraction) were observed in matured cow's milk cheese. In vitro digestion slightly improved the radical scavenging capacity of WSF, whereas digested WINF had more than twice the capacity of their undigested counterparts. The cheeses prepared in this study could be a good source of antioxidant peptides. Further investigations of their in vitro and in vivo functionality need to be conducted

Genotype x Environment interaction for antioxidants and phytic acid contents in bread and durum wheat as influenced by climate

Antioxidants prevent oxidative stress and exert positive health effects. However, phytic acid among them decreases micronutrients absorption, representing also antinutrient to human and non-ruminant animals. Fifteen bread wheat (Triticum aestivum L.) and 15 durum wheat (Triticum durum Desf.) genotypes were evaluated across six environments to determine contents of phytic acid (PA), inorganic P (Pi), total yellow pigment, total soluble phenolic compounds, free protein sulfhydryl groups (PSH), and also phytic acid P/P-i (P-p/P-i). The objective of this study was to quantify, for each trait the effects of environment, genotype, and their interaction; and the influence of climatic factors on the Genotype x Environment interaction (GEI) by the use of the factorial regression. GEI (P lt 0.001) prevailed as source of variation over genotype (P lt 0.001) in determining PA content in bread and durum wheat (44.3% and 34.7% of sum of squares-SS, respectively), PSH content in bread and durum wheat (27% and 28.4% of SS, respectively) and total soluble phenolic compounds content in durum wheat (35.5% of SS). The major contribution to the GEI represented climatic variables during stages of stem elongation for PA and phenolic compounds, and also flowering, fertilization, grain formation and grain filling for PSH. Total yellow pigment and Pi contents in bread and durum wheat were predominantly determined by genotype (P lt 0.001). Models of climatic variables proved to be efficient in the explanation of more than 92% of the SS of GEI for PA and antioxidants contents

Mineral Elements, Lipoxygenase Activity, and Antioxidant Capacity of Okara as a Byproduct in Hydrothermal Processing of Soy Milk

Minerals and antioxidative capacity of raw okara that was obtained as a byproduct from six soybean varieties during hydrothermal cooking (HTC) of soy milk were assessed. Lipoxygenase (Lox), an enzyme deteriorating the sensory characteristics of okara, was also investigated. All genotypes had very similar concentrations of Lox (4.32-5.62%). Compared to raw soybeans, the applied HTC significantly reduced Lox content in okara (0.54-0.19%) and lowered its activity to 0.004-0.007 mu mol g(-1) min(-1). Correlation between the content of Lox in soybeans and that in okara (r = 0.21;p lt 0.05) was not registered. This indicates that the content of this enzyme in okara depended much more on the technological process than on soybean genotype. Very strong correlation (r = 0.99; p lt 0.05) between okara Lox content and its activity was found. The most abundant minerals in raw okara were potassium (1.04-1.21 g/100g), phosphorus (0.45-0.50 g/100 g), calcium (0.26-0.39 g/100 g), and iron (5.45-10.95 mg/100 g). A very high antioxidant capacity (19.06-29.36 mmol Trolox kg(-1) contributes to the nutritional value of raw okara

The polypeptide composition, structural properties and antioxidant capacity of gluten proteins of diverse bread and durum wheat varieties, and their relationship to the rheological performance of dough

The aim of this study was to compare five bread and five durum wheat genotypes for gliadins and glutenins profiles, the concentration of free sulphhydryl groups and disulphide bonds, antioxidant capacity of gluten proteins and their bread-making performance. On average, bread wheat had significantly higher concentration of total sulphur-rich (S-rich) and sulphur-poor (S-poor) subunits of gliadins, as well as total low molecular weight (LMW) and high molecular weight (HMW) subunits of glutenins than durum wheat. However, durum wheat had higher concentration of S-rich gamma-gliadins and S-poor D-LMW-glutenins, but did not possess S-poor omega-gliadins. The concentration of disulphide bonds and total cysteine was higher in the durum gluten than that in the bread gluten, as well as antioxidant capacity (on average 90.6 vs. 85.9 mmol Trolox Eq kg(-1), respectively). In contrast to the bread wheat, the concentration of HMW-glutenins was negatively associated with extensibility, as well as resistance to extension in durum wheat flour dough