Influence of content of [beta] conglycinine subunits on technological and functional properties of soybean proteins

Zbog značajne nutritivne vrednosti i visokog sadržaja proteina, antioksidanasa i nezasićenih masnih kiselina soja se svrstava u kategoriju funkcionalne hranu. Zdravstveni efekti soje u humanoj ishrani su brojni: doprinosi smanjenju koncentracije glukoze i holesterola u krvi, pokazuje antioksidativni efekat, povoljno utiče na održavanje hormonske ravnoteže, sprečava osteoporozu i deluje preventivno na različite tipove kancera. Na tehnološki značajne funkcionalne osobine proteina semena soje najviše utiču dva glavna rezervna proteina: glicinin (11S protein) i β konglicinin (7S protein). I 11S i 7S proteini se javljaju u više izoformi. Molekul glicinin čine dva neglikozilovana heksamera koji se sastoje iz parova kiselih i baznih polipeptida povezanih disulfidnim mostom.β konglicinin je glikozilovani trimerni protein koji se sastoji iz tri podjedinice- α, α' i β. Pojedine sorte soje, među kojima su naročito brojne domaće sorte, sintetišu dodatnu β' podjedinicu. Premda je efekat ostalih podjedinica β konglicinina na tehnološka funkcionalna svojstva proteina soje intenzivno proučavan, u literaturi postoji veliki broj kontradiktornih podataka. O efektima β' podjedinice na rastvorljivost, emulgujuća i gelirajuća svojstva sojinih proteina veoma malo se zna. Cilj ovog rada bio je da se ispita efekat polipeptidnog sastava glicinina i β konglicinina na rastvorljivost, emulgujuća i gelirajuća svojstva proteina na različitim pH vrednostima (3, 5, 6 i 8) na seriji od 9 različitih genotipova soje gajenih u dve sukcesivne godine. Uspostavljanje korelacija između specifičnih podjedinica sojinih proteina i željenog svojstva pri datoj pH vrednosti, omogućilo bi ne samo selekciju sorti pogodnih za dati tehnološki proces, već bi uticalo i na osobine gotovih proizvoda. Povećana rastvorljivost obezbeđivala bi lakše usvajanje aminokiselina i bolju svarljivost. Pored povećane biološke vrednosti, visoka rastvorljivost je u pozitivnoj korelaciji sa funkcionalnim svojstvima poput geliranja i penivosti...Because of its nutritive value and high content of proteins, antioxidants and unsaturated fatty acids, soybeans have been regarded as functional food. Health benefits of inclusion of soy in human diet are numerous: it helps diminishing concentration of glucose and cholesterol in blood, has antioxidative effect, helps in regulating hormonal balance, prevents osteoporosis and has protective influence against different types of cancers. The strongest influence on technological functional properties of soybean proteins is exhibited by two reserve proteins: glycinin (11S protein) i β conglycinin (7S protein). Both 11S and 7S protein are present in different isoforms. Glycinin molecule is composed of two non-glycosilated hexamers that contain pairs of acidic and basic polypeptides linked together by disulfide bonds. β conglycinin is glycosilated trimeric protein composed of three types of subunits - α, α' and β. Some varieties of soybean, among them numerous varieties grown in Serbia, are synthesizing additional β' subunit. Although effects of other subunits of β conglycinin on technological functional properties of soybean proteins have been extensively studied, there is still a high number of contradictory data in literature. Little is known about influence of β' subunit on solubility, emulsifying and gelling properties of soybean proteins. The aim of this work was to examine effect of polypeptide composition of glycinine and β conglycinine on solubility, emulsifying and gelling properties of soybean proteins at different pH values (3, 5, 6 and 8) on series of 9 different genotypes grown in two successive years. Establishing correlation of specific subunit of soybean protein with desired characteristic on given pH value would allow not only selection of varieties of soybean suitable for particular technological process, but would also have impact on properties of finished product. Higher protein solubility would allow better usage of amino acids and would also give higher digestibility..

The extraction of antioxidative compounds from rusks enriched with millet flour (Panicum miliaceum L.)

Two different ways of extracting antioxidative compounds (including soluble polyphenols) from rusks made from wheat flour with added millet (Panicum miliaceum L.) were compared, i.e., solvent extraction and in vitro digestion. Wheat flour was replaced by millet flour in amounts of 10, 20 or 30 wt. % (per dry mass). Solvent extraction was realized using a mixture of ethanol and water in different percentages, with or without the addition of formic acid. The total content of phenolic compounds (TPC) was determined using Folin-Ciocalteu reagent, while the antioxidative capacity was measured by the DPPH (2,2-diphenyl-1-picrylhydrazyl) assay. The efficiency of solvent extraction was enhanced by the addition of formic acid. The addition of millet flour in amounts up to 20 % enhanced the antioxidative properties. It was shown that in vitro digestion was more efficient in the extraction of antioxidative compounds, in comparison with solvent extraction

Control measures of handling and processing raw fish meat in order to prevent fish borne parasitic zoonoses

Последњих година, као последица глобализације и промена културолошких и кулинарских навика становништва, забележен је пораст броја људи инфи- цираних паразитима услед конзумације сировог или недовољно температурно обрађеног рибљег меса. Евисцерација рибе брзо након улова, као и адспекција и преглед меса пре пуштања у промет или пре конзумације представљају превентивне мере. Међутим, уколико се паразити ипак појаве у месу, постоје бројни хемијски и физички третмани које убијају паразите и након којих месо постаје безбедно за употребу. Поред стандардних, постоје и експерименталне методе за инактивацију паразита, као што је употреба електричне струје ниског напона или неконвенционални, традиционални начини, као што је употреба зачина.In the last few years, as a result of globalisation and changes in cultural habits and culinary practices there has been noted increasing in the number of parasitic infection in people caused by consumption of raw or undercooked fish meat and fishery products. Evisceration of fish soon after catching, adspection and control of fish meat before the consumption are preventing measures. If there are parasites in fish tissue they can be killed by using physical or chemical treatments. Moreover, there are some experimental methods such as low voltage current or non conventional, traditional method like using some vegetable products

Functional Properties of Pea (Pisum sativum, L.) Protein Isolates Modified with Chymosin

In this paper, the effects of limited hydrolysis on functional properties, as well as on protein composition of laboratory-prepared pea protein isolates, were investigated. Pea protein isolates were hydrolyzed for either 15, 30 and 60 min with recombined chymosin (Maxiren). The effect of enzymatic action on solubility, emulsifying and foaming properties at different pH values (3.0; 5.0; 7.0 and 8.0) was monitored. Chymosin can be a very useful agent for improvement of functional properties of isolates. Action of this enzyme caused a low degree of hydrolysis (3.9–4.7%), but improved significantly functional properties of pea protein isolates (PPI), especially at lower pH values (3.0–5.0). At these pH values all hydrolysates had better solubility, emulsifying activity and foaming stability, while longer-treated samples (60 min) formed more stable emulsions at higher pH values (7.0, 8.0) than initial isolates. Also, regardless of pH value, all hydrolysates showed improved foaming ability. A moderate positive correlation between solubility and emulsifying activity index (EAI) (0.74) and negative correlation between solubility and foam stability (−0.60) as well as between foam stability (FS) and EAI (−0.77) were observed. Detected enhancement in functional properties was a result of partial hydrolysis of insoluble protein complexes

Influence of content of [beta] conglycinine subunits on technological and functional properties of soybean proteins

Zbog značajne nutritivne vrednosti i visokog sadržaja proteina, antioksidanasa i nezasićenih masnih kiselina soja se svrstava u kategoriju funkcionalne hranu. Zdravstveni efekti soje u humanoj ishrani su brojni: doprinosi smanjenju koncentracije glukoze i holesterola u krvi, pokazuje antioksidativni efekat, povoljno utiče na održavanje hormonske ravnoteže, sprečava osteoporozu i deluje preventivno na različite tipove kancera. Na tehnološki značajne funkcionalne osobine proteina semena soje najviše utiču dva glavna rezervna proteina: glicinin (11S protein) i β konglicinin (7S protein). I 11S i 7S proteini se javljaju u više izoformi. Molekul glicinin čine dva neglikozilovana heksamera koji se sastoje iz parova kiselih i baznih polipeptida povezanih disulfidnim mostom.β konglicinin je glikozilovani trimerni protein koji se sastoji iz tri podjedinice- α, α' i β. Pojedine sorte soje, među kojima su naročito brojne domaće sorte, sintetišu dodatnu β' podjedinicu. Premda je efekat ostalih podjedinica β konglicinina na tehnološka funkcionalna svojstva proteina soje intenzivno proučavan, u literaturi postoji veliki broj kontradiktornih podataka. O efektima β' podjedinice na rastvorljivost, emulgujuća i gelirajuća svojstva sojinih proteina veoma malo se zna. Cilj ovog rada bio je da se ispita efekat polipeptidnog sastava glicinina i β konglicinina na rastvorljivost, emulgujuća i gelirajuća svojstva proteina na različitim pH vrednostima (3, 5, 6 i 8) na seriji od 9 različitih genotipova soje gajenih u dve sukcesivne godine. Uspostavljanje korelacija između specifičnih podjedinica sojinih proteina i željenog svojstva pri datoj pH vrednosti, omogućilo bi ne samo selekciju sorti pogodnih za dati tehnološki proces, već bi uticalo i na osobine gotovih proizvoda. Povećana rastvorljivost obezbeđivala bi lakše usvajanje aminokiselina i bolju svarljivost. Pored povećane biološke vrednosti, visoka rastvorljivost je u pozitivnoj korelaciji sa funkcionalnim svojstvima poput geliranja i penivosti...Because of its nutritive value and high content of proteins, antioxidants and unsaturated fatty acids, soybeans have been regarded as functional food. Health benefits of inclusion of soy in human diet are numerous: it helps diminishing concentration of glucose and cholesterol in blood, has antioxidative effect, helps in regulating hormonal balance, prevents osteoporosis and has protective influence against different types of cancers. The strongest influence on technological functional properties of soybean proteins is exhibited by two reserve proteins: glycinin (11S protein) i β conglycinin (7S protein). Both 11S and 7S protein are present in different isoforms. Glycinin molecule is composed of two non-glycosilated hexamers that contain pairs of acidic and basic polypeptides linked together by disulfide bonds. β conglycinin is glycosilated trimeric protein composed of three types of subunits - α, α' and β. Some varieties of soybean, among them numerous varieties grown in Serbia, are synthesizing additional β' subunit. Although effects of other subunits of β conglycinin on technological functional properties of soybean proteins have been extensively studied, there is still a high number of contradictory data in literature. Little is known about influence of β' subunit on solubility, emulsifying and gelling properties of soybean proteins. The aim of this work was to examine effect of polypeptide composition of glycinine and β conglycinine on solubility, emulsifying and gelling properties of soybean proteins at different pH values (3, 5, 6 and 8) on series of 9 different genotypes grown in two successive years. Establishing correlation of specific subunit of soybean protein with desired characteristic on given pH value would allow not only selection of varieties of soybean suitable for particular technological process, but would also have impact on properties of finished product. Higher protein solubility would allow better usage of amino acids and would also give higher digestibility..

Influence of content of [beta] conglycinine subunits on technological and functional properties of soybean proteins

Zbog značajne nutritivne vrednosti i visokog sadržaja proteina, antioksidanasa i nezasićenih masnih kiselina soja se svrstava u kategoriju funkcionalne hranu. Zdravstveni efekti soje u humanoj ishrani su brojni: doprinosi smanjenju koncentracije glukoze i holesterola u krvi, pokazuje antioksidativni efekat, povoljno utiče na održavanje hormonske ravnoteže, sprečava osteoporozu i deluje preventivno na različite tipove kancera. Na tehnološki značajne funkcionalne osobine proteina semena soje najviše utiču dva glavna rezervna proteina: glicinin (11S protein) i β konglicinin (7S protein). I 11S i 7S proteini se javljaju u više izoformi. Molekul glicinin čine dva neglikozilovana heksamera koji se sastoje iz parova kiselih i baznih polipeptida povezanih disulfidnim mostom.β konglicinin je glikozilovani trimerni protein koji se sastoji iz tri podjedinice- α, α' i β. Pojedine sorte soje, među kojima su naročito brojne domaće sorte, sintetišu dodatnu β' podjedinicu. Premda je efekat ostalih podjedinica β konglicinina na tehnološka funkcionalna svojstva proteina soje intenzivno proučavan, u literaturi postoji veliki broj kontradiktornih podataka. O efektima β' podjedinice na rastvorljivost, emulgujuća i gelirajuća svojstva sojinih proteina veoma malo se zna. Cilj ovog rada bio je da se ispita efekat polipeptidnog sastava glicinina i β konglicinina na rastvorljivost, emulgujuća i gelirajuća svojstva proteina na različitim pH vrednostima (3, 5, 6 i 8) na seriji od 9 različitih genotipova soje gajenih u dve sukcesivne godine. Uspostavljanje korelacija između specifičnih podjedinica sojinih proteina i željenog svojstva pri datoj pH vrednosti, omogućilo bi ne samo selekciju sorti pogodnih za dati tehnološki proces, već bi uticalo i na osobine gotovih proizvoda. Povećana rastvorljivost obezbeđivala bi lakše usvajanje aminokiselina i bolju svarljivost. Pored povećane biološke vrednosti, visoka rastvorljivost je u pozitivnoj korelaciji sa funkcionalnim svojstvima poput geliranja i penivosti...Because of its nutritive value and high content of proteins, antioxidants and unsaturated fatty acids, soybeans have been regarded as functional food. Health benefits of inclusion of soy in human diet are numerous: it helps diminishing concentration of glucose and cholesterol in blood, has antioxidative effect, helps in regulating hormonal balance, prevents osteoporosis and has protective influence against different types of cancers. The strongest influence on technological functional properties of soybean proteins is exhibited by two reserve proteins: glycinin (11S protein) i β conglycinin (7S protein). Both 11S and 7S protein are present in different isoforms. Glycinin molecule is composed of two non-glycosilated hexamers that contain pairs of acidic and basic polypeptides linked together by disulfide bonds. β conglycinin is glycosilated trimeric protein composed of three types of subunits - α, α' and β. Some varieties of soybean, among them numerous varieties grown in Serbia, are synthesizing additional β' subunit. Although effects of other subunits of β conglycinin on technological functional properties of soybean proteins have been extensively studied, there is still a high number of contradictory data in literature. Little is known about influence of β' subunit on solubility, emulsifying and gelling properties of soybean proteins. The aim of this work was to examine effect of polypeptide composition of glycinine and β conglycinine on solubility, emulsifying and gelling properties of soybean proteins at different pH values (3, 5, 6 and 8) on series of 9 different genotypes grown in two successive years. Establishing correlation of specific subunit of soybean protein with desired characteristic on given pH value would allow not only selection of varieties of soybean suitable for particular technological process, but would also have impact on properties of finished product. Higher protein solubility would allow better usage of amino acids and would also give higher digestibility..

Uticaj metode ekstrakcije na proteinske profile proteina soje

Comparison between protein profiles of soybean obtained by commonly used methods of extraction (Tris buffer and Tris-urea buffer) with methods used for extraction of plant proteins for 2D PAGE analysis (direct solubilization in IEF buffer, acetone extraction, phenol extraction, extraction with urea solubilization buffer and thiourea-urea extraction) was investigated. 2D profiles of samples extracted directly in IEF buffer, in urea solubilization buffer and in acetone were characterized with low number of spots. Analysis of 2D PAGE profiles of Tris buffer and Tris-urea buffer extracts showed high degree of horizontal and vertical streaking. Thiourea-urea extraction gave a higher number of less intense protein spots than phenol extraction. The method of choice, due to a large number of intense spots, would be phenol extraction.Upoređeni su profili proteina semena soje dobijeni tradicionalnim metodama ekstrakcije (Tris-HCl puffer i Tris-urea pufer) sa profilima proteina soje ekstrahovanim metodama koje se obično koriste za ekstrakciju biljnih proteina za 2D PAGE analizu (direktno rastvaranje u IEF puferu, acetonska ekstrakcija, fenolna ekstrakcija, ekstrakcija puferom sa ureom i tiourea/urea ekstrakcija). Cilj rada je bio utvrditi primenljivost ekstrakcije Tris-HCl i Tris-urea puferom u 2D PAGE analizi. Raširena primena ove dve metode ekstrakcije zasnovana je na dobijanju visoke koncentracije proteina koji se karakterišu dobrom rastvorljivošću, kao i na već dobro poznatim Rf vrednostima pojedinih proteinskih podjedinica na SDS PAGE elektroforegramima visoke rezolucije. Tako bi njihova eventualna primena u proteomiks analizama, omogućila kako brzu analizu uzoraka, tako i prikupljanje većeg broja podataka, jer bi se izbegla potreba za resolubilizacijom i gubitak proteina. Poređenje ekstrakcionih metoda vršeno je na osnovu broja rastvornih proteina u ekstraktu, kao i denzitometrijskih merenja broja, intenziteta i oštrine tačaka na 2D profilima u okviru dva različita pH opsega. Premda ekstrakcije sa Tris-HCl i Tris-urea puferom daju najveću koncentraciju proteina u ekstraktu, ove metode daju manji broj tačaka u poredjenju sa ostalim ispitivanim metodama. Takođe, izraženo vertikalno i horizontalno 'razvlačenje' onemogućavaju preciznu denzitometrijsku analizu. Dodatni nedostatak ovih metoda (pogotovu ekstrakcije sa Tris-HCl puferom) jeste produženo vreme potrebno za korak izoelektričnog fokusiranja u poredjenju sa ostalim metodama. Direktna ekstrakcija u IEF puferu i ekstrakcija puferom sa ureom daju slične rezultate i karakterišu se malim brojem difuznih tačaka. Acetonskom ekstrakcijom dobija se mala koncentracija rastvorljivih proteina, a na 2D PAGE profilima uočava se visok stepen horizontalnog razvlačenja. Tiourea- urea ekstrakcija daje veći broj manje intenzivnih tačaka u poređenju sa fenolnom ekstrakcijom. Manji intenzitet tačaka može značiti gubitak manje zastupljenih proteina. U slučaju fenolne ekstrakcije, veliki broj koraka tokom pripreme uzorka produžava vreme analize, ali su tačke najintenziivnije. Na osnovu dobijenih rezultata, zaključeno je da je fenolna ekstrakcija metoda izbora za ekstrakciju proteina iz semena soje za analizu 2D PAGE metodom

Functional properties of protein hydrolysates from pea (Pisum sativum, L) seeds

The aim of this study was to investigate the effects of partial enzymatic hydrolysis on functional properties of two different pea protein isolates obtained from two pea genotypes, Maja and L1. Papain and commercial protease (Streptomyces griseus protease) were used for protein modification. Solubility, emulsifying and foaming properties were estimated at four different pH values (3.0, 5.0, 7.0 and 8.0). Papain increased solubility of L1 pea protein isolate at pH 3.0, 5.0 and 8.0, emulsifying properties and foaming capacity at all pH values. Otherwise, papain increased solubility of Maja pea protein isolate only at pH 8.0. This pea protein isolate modified with both enzymes formed emulsions with improved stability at lower pH (3.0, 5.0). The commercial protease-prepared pea protein isolates showed generally low solubility and different emulsifying and foaming properties. Proper selection of enzyme, conditions of hydrolysis and genotypes could result in production of pea protein isolates with desirable functional properties

Examination of changes in total volatile nitrogen during the storage of cold smoked fish

Smoked fish, especially cold-smoked fish, is one of the most respected fish products. Since this is a "ready to eat" product, a particular attention is given to the packaging and changing during storage (bacteriological status, physical and chemical characteristics, sensory properties). The cold-smoked fish most commonly is packaged in the vacuum and modified atmosphere (MAP). The aim of this study was to evaluate the changes in the content of total volatile nitrogen (TVN) in the cold smoked fish packaged in a vacuum and MAP. For the experiment slices of cold smoked trout were packaged in a vacuum (O-I group) and three different modified atmospheres (O-II: 50% CO2+50% N2; O-III: 60% CO2+40% N2 and O-IV: 90% Co2+10% N2). The fish is stored after packaging at a temperature of 3 ℃, and the content of TVN was examined on days 0,7, 14,21,28,35 and 42. The content of TVN was determined by reaction of titration with hydrochloric acid in the presence of 3% of boric acid and methyl red and methyl blue as indicators. The content of TVN in samples of O-I group was from 3.52±0.24 ppm (on day 0) to 28.38±3.22 ppm (day 42), in O-II group from 3.02±0.06 ppm to 23.72±7.45 ppm, in O-III group from 3.07±0.09 ppm to 39.26±10.78 ppm and in samples of O-IV group TVN content was from 3.12±0.07 ppm to 36.15±4.47 ppm (respectively). During the 6 weeks of storage, the TVN in the samples of all four groups of cold smoked fish grew throughout the whole storage period, as can be seen from the regression equation for O-I, O-II, O-il and IV-O group: y=3.3019x+3.1481, y=2.6366x+4.6628, y=4.9603x-0.7559 and y=4.9762x-0.0561 (respectively). From the shown data it can be concluded that, based on the content of TVN as an indicator of spoilage, the least changes were detected in samples of O-II group, then O-I group, while the most pronounced changes were in the samples O-III and O-IV group of cold-smoked trout.Zbornik kratkih sadržaj