Ispitivanje sadržaja i antioksidativne aktivnosti fenolnih kiselina u toku proizvodnje slada i piva

Autor: Pejin Jelena
Jazyk: srbština
Rok vydání: 2009
Předmět:
Druh dokumentu: Diplomová práce
Popis: Cilj istraživanja doktorske disertacije je bio da se ukonitnuitetu ispita sadržaj ukupnih fenola, fenolnih kiselina ianitoksidativna aktivnost (antiradikalska aktivnost na DPPH ihidroksil radikale) u toku proizvodnje slada i piva (u ječmu,namočenom ječmu, zelenom sladu, sladu, sladovini, ohmeljenojsladovini, sladovini tokom fermentacija, mladom pivu i pivu)proizvedenih od tri priznate sorte pivskog ječma: NS 525, NS565 i NS 583.Sadržaj ukupnih fenola u uzorcima ječma je bio: NS 525 -0,76; NS 565 - 0,75 i NS 583 - 0,70 mg GAE/g suve materije.Sadržaj ukupnih fenola u svim proizvednim sladovima (0,96;0,94 i 0,91 mg GAE/g suve materije za NS 525; NS 565 i NS583) je bio viši od sadržaja u ječmu. Sorta NS 525 je imalanajviši sadržaj ukupnih fenola tokom svih faza sladovanja, doksu sorte NS 565 i NS 583 imale niže sadržaje ukupnih fenola.Najniži sadržaj ukupnih fenola imala je sorta NS 583.U svim ispitivanim sortama ječma ferulna, p-kumarinska ivanilinska kiselina su bile dominantne u uzorcima ječma,tokom sladovanja i u proizvedenom sladu.Sadržaj ukupnih fenolnih kiselina u ječmu je iznosio za sortuNS 525 - 200,98; NS 565 - 184,10 i za NS 583 – 177,27 μg/g suvematerije. Sadržaj ukupnih fenolnih kiselina je rastao kod svihispitivanih sorti tokom močenja i dostigao maksimum u tokuprvog dana klijanja za NS 525 – 548,31; NS 565 – 518,65 i NS583 – 517,17 μg/g suve materije. Dobijeni rezultati su pokazalida je proces sladovanja imao značajan uticaj na sadržajpojedinačnih i ukupnih fenolnih kiselina.Sorta NS 525 je imala najvišu antiradikalsku aktivnost naDPPH radikale (EC50 za NS 525 - 0,658; NS 565 - 0,667 i NS583 - 0,758 mg/ml) što pokazuje da sorta ječma ima uticaja naantiradikalsku aktivnost na DPPH radikale. Za ispitivane sorteječma, antiradikalska aktivnost na DPPH radikale se povisilaznačajno tokom močenja. U proizvedenim sladovimaantiradikalska aktivnost na DPPH radikale bila je viša nego uječmu. Trend porasta i smanjenja antiradikalske aktivnosti naDPPH radikale tokom sladovanja je bio isti za sve ispitivanesorte ječma.Antiradikalska aktivnost na hidroksil radikale, izražena kaoEC50 vrednost, u ispitivanim sortama ječma je iznosila: NS 525– 0,352; NS 565 – 0,385 i NS 583 – 0,455 mg/ml. Može sezaključiti da je sorta NS 525 imala najvišu antiradikalskuaktivnost na hidroksil radikale. Antiradikalska aktivnost nahidroksil radikale se znatno povisila tokom močenja. Uproizvedenom sladu je antiradikalska aktivnost na hidroksilradikale bila viša nego u ječmu. Trend porasta i smanjenjaantiradikalske aktivnosti na hidroksil radikale tokomsladovanja je bio isti za sve ispitivane sorte ječma.Sorta NS 525 je imala najviši sadržaj ukupnih fenola kao inajvišu antioksidativnu aktivnost tj. DPPH i hidroksilantiradikalsku aktivnost. Ovi rezultati pokazuju da sortaječma može da utiče na antiradikalske osobine slada. Sorta NS525 je imala najviši sadržaj ukupnih fenola, ukupnih fenolnihkiselina i najvišu antiradikalsku aktivnost na DPPH i hidroksilradikale u toku sladovanja.U svim proizvedenim sladovinama, ohmeljenim sladovinama ipivima, ferulna, p-kumarinska, vanilinska i sinapinska kiselinasu imale najviše sadržaje. Sadržaj svih ispitivanih fenolnihkiselina je povišen nakon hmeljenja. Najviši ukupni sadržajfenolnih kiselina je odreñen u ohmeljenim sladovinama (NS525 - 461,41, NS 565 - 426,22 i NS 583 - 423,56 μg/100ml).Sadržaj ukupnih fenolnih kiselina je u svim proizvedenimpivima bio niži u odnosu na odgovarajuće ohmeljene sladovine.U sladovini proizvedenoj iz slada NS 525 je odreñena najvišaantiradikalska aktivnost na DPPH i hidroksil radikale štoukazuje da antiradikalska aktivnosti komponenti slada imauticaja na antiradikalsku aktivnost proizvedene sladovine. Uispitivanim sladovinama, nakon hmeljenja se znatno povisilaantiradikalska aktivnost na DPPH i hidroksil radikale.Antiradikalska aktivnost na DPPH i hidroksil radikale sesmanjila tokom glavne i naknadne fermentacije.U sladovini proizvedenoj od slada NS 525 sa najvišimsadržajem ukupnih fenola i ukupnih fenolnih kiselinaodreñena je najviša antiradikalska aktivnost na DPPH ihidroksil radikale. Tokom proizvodnje piva sadržaj ukupnihfenola se blago smanjio, što ukazuje da je proces proizvodnjeimao uticaja na njihov sadržaj. Trend smanjenjaantiradikalske aktivnosti na DPPH i hidroksil radikaleodgovara smanjenju sadržaja ukupnih fenola i ukupnihfenolnih kiselina tokom procesa proizvodnje piva.Primenjena GC-MS metoda za odreñivanje sadržaja fenolnihkiselina tokom procesa proizvodnje slada i piva se pokazalakao osetljiva, specifična i dobre ponovljivosti. Može seprimeniti za odreñivanje sadržaja fenolnih kiselina u ječmu,namočenom ječmu, zelenom sladu, sladu, sladovini, ohmeljenojsladovini, tokom fermentacije i u pivu.Sadržaj ukupnih fenola, fenolnih kiselina i antioksidativnaaktivnost slada, koji se koristi za proizvodnju piva, imajuznačajan uticaj na antioksidativnu aktivnost piva.Razumevanje promena sadržaja fenolnih kiselina iantioksidativne aktivnosti tokom proizvodnje slada i piva moženam pružiti vredne informacije o zaštiti endogenihantioksidanata u proizvodnji piva. Na taj način mogu seproizvoditi piva sa višom antioksidativnom aktivnošću i prematome i povišenom otpornošću prema lipidnoj oksidaciji istarenju piva.
Studies carried out in the frame of the doctorial thesisaimed at continuous determination of the content oftotal phenolics, phenolic acids and antioxidant activity(antiradical activity on DPPH and hydroxyl radicals)during malt and beer production (in barley, steepedbarley, green malt, malt, wort, hopped wort,fermenting wort, green beer, and beer) produced fromthree accepted brewer’s barley varieties: NS 525, NS565, and NS 583.The total phenolics content in the barley samples was0.76 for NS 525, 0.75 for NS 565 and 0.70 mg GAE/gdry matter (d.m.) for NS 583. Higher content of totalphenolics was determined in the malt samples incomparison with the barley samples: (0.96, 0.94, and0.91 mg GAE/g d.m. for NS 525, NS 565, and NS 583,respectively). Variety NS 525 was the highest in totalphenolics content during all stages of malting whencompared to the other varieties. The lowest content oftotal phenolics was found in the variety NS 583.In all examined samples, ferulic, p-coumaric andvanillic acid dominated in the barley samples, duringmalting and in the produced malts.Content of total phenolic acids in the barley sampleswas 200.98 for NS 525, 184.10 for NS 565 and 177.27mg/g d.m. for NS 583. During steeping, the content oftotal phenolic acids increased for all samples reachingthe maximum at the first day of germination (NS 525 –548.31; NS 565 – 518.65, and NS 583 – 517.17 μg/gd.m.). The obtained results revealed that the maltingprocess had significant impact on the content of totaland individual phenolic acids.Variety NS 525 showed the highest antiradical activityon DPPH radicals (EC50 for NS 525 was 0.658, for NS565 0.667, and for NS 583 0.758 mg/ml) indicating thatbarley variety influences the antiradical activity onDPPH radicals. Antiradical activity on DPPH radicalssignificantly increased during steeping for allinvestigated barley varieties. Higher antiradicalactivity on DPPH radicals was determined inproduced malts when compared to correspondingbarley varieties. Similar increasing and decreasingtrends in the antiradical activity on DPPH radicalsduring malting were observed in all investigatedbarley varieties.The antiradical activity on hydroxyl radicals,expressed as EC50 value, in investigated barleyvarieties, was: 0.325 for NS 525, 0.385 for NS 565, and0.455 mg/ml for NS 583. It can be concluded thatbarley variety NS 525 showed the highest antiradicalactivity on hydroxyl radicals. The antiradical activityon hydroxyl radicals significantly increased duringsteeping. Higher antiradical activity on hydroxylradicals was determined in produced malts whencompared to corresponding barley varieties. Similarincreasing and decreasing trends in the antiradicalactivity on hydroxyl radicals during malting wereobserved in all investigated samples.Variety NS 525 had the highest content of totalphenolics and exhibited the highest antioxidantactivity that is antiradical activity on DPPH andhydroxyl radicals. These results suggest that varietycan influence the malt antiradical properties. VarietyNS 525 was the highest in total phenolics content, totalphenolic acids content and antiradical activity onDPPH and hydroxyl radicals during malting.The highest contents of ferulic, p-coumaric, vanillic,and sinapic acids were determined in all wort, hoppedwort and beer samples. Increased contents of allphenolic acids were observed after hopping. Thehighest content of total phenolic acids was determinedin the hopped worts (461.41 for NS 525, 426.22 for NS565, and 423.56 μg/100 ml for NS 583. The beerscontained less total phenolic acids when compared tothe corresponding hopped worts.Wort produced from NS 525 malt showed the highestantiradical activity on DPPH and hydroxyl radicalswhich indicates that the antiradical activity of maltcomponents affects the antiradical activity in producedwort. After hopping, antiradical activity on DPPH andhydroxyl radicals significantly increased in all worts.The antiradical activity on DPPH and hydroxylradicals decreased during primary and secondaryfermentation.Wort produced from NS 525 malt contained thehighest total phenolic content, total phenolic acidscontent and showed the highest antiradical activity onDPPH and hydroxyl radicals. During beer production,content of total phenolic compounds slightly decreasedwhich indicates that production process had aninfluence on their content. Similar decreasing trendsbetween the antiradical activity on DPPH andhydroxyl radicals and the contents of total phenolicsand total phenolic acids during beer production wereobserved.The applied GC-MS method for determination ofphenolic acids contents during malt and beerproduction was sensitive, specific and had goodrepeatability. It can be used for determination ofphenolic acids content in barley, steeped barley, greenmalt, malt, wort, hopped wort, during fermentationand in beer.The content of total phenolics, phenolic acids andantioxidant activity of malt used for beer productionhave significant influence on the beer antioxidantactivity. Understanding how the phenolic acids andantioxidant activity change during malt and beerproduction can provide valuable information aboutthe protection of endogenous antioxidants in beerproduction. In this way, the production of beer withenhanced antioxidant activity is possible and thereforehigher resistance to lipid oxidation and longer shelflifecould be introduced.
Databáze: Networked Digital Library of Theses & Dissertations
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