Abstract | Cilj ovog istraživanja bio je utvrditi utjecaj vremena na sintezu organosumpornih spojeva (OSS) češnjaka i njihovih derivata nakon mehaničkog oštećenja svježih češnjeva češnjaka (sjeckanje i oksidacija na zraku u trajanju 2, 5, 8 i 11 min), utjecaj vremena blanširanja (1, 5 i 10 min) pri 100 oC, te utjecaj vremena prženja (1, 3 , 5, 9 i 11 min) pri temperaturi 120 oC na stabilnost spomenutih spojeva. U drugom dijelu istraživanja određivana je stabilnost organosumpornih spojeva u vodenom ekstraktu češnjaka (ekstrakt OSS češnjaka nasjeckanog i oksidiranog na zraku u trajanju 8 min) tijekom skladištenja na temperaturama +4°C , -20°C i -80°C kroz period od 15 dana Određivanje organosumpornih spojeva provedeno je primjenom HPLC UV/PDA metode. U svima uzorcima najzastupljeniji je bio S-metil-metantiosulfinat (TiMe2), a u padajućem nizu slijede izomeri S-2-propenil-metantiosulfinat/ S-metil-2-propentiosulfinat (TiMeAl/TiAlMe), alicin (TiAl2), S-1-propenil-2-propentiosulfinat/S-2-propenil-1-propentiosulfinat (TiPeAl/TiAlPe), S-1-propenil-metantiosulfinat/ S-metil-1-propentiosulfinat (TiMePe/TiPeMe) i neidentificirani spoj. Nakon mehaničkog oštećivanja maseni udio TiMe2 se povećavao do 11 minute, dok su se ostali OSS povećavali do 8 minute, nakon čega je uslijedila djelomična degradacija. Najstabilniji tijekom termičke obrade bio je TiMe2, čiji se maseni udio tijekom prženja povećavao, a tijekom blanširanja se neznatno smanjivao. Istovremeno, termička obrada (prženje i blanširanje) utjecala je na značajno smanjenje masenih udjela svih ostalih OSS. Tijekom skladištenja vodenog ekstrakta češnjaka kroz period od 15 dana najstabilniji je bio TiMe2, a nakon 6 dana skladištenja koncentracija mu se smanjila za 25%. Ostali OSS su značajno degradirali već nakon 3 dana skladištenja (20 do 30 %), a najnestabilniji je bio alicin. |
Abstract (english) | The aim of this study was to determine the influence of time on synthesis of organosulfur compounds (OSC) and their derivatives after mechanical damage of fresh clove garlic (cutting and oxidation in the air lasting 2, 5, 8 and 11 min), the influence of blanching time (1, 5 and 10 min) at 100 oC and the influence of frying time (1, 3, 5, 9 and 11 min) at 120 oC on the stability of mentioned compounds. In the second part of the study, the organosulfur compounds stability in garlic water extract (extract OSC of cutted garlic, oxidised in the air for 8 min) storage at the temperature +4oC, -20oC and – 80oC during the period of 15 days was determined. The organosulfur compounds were determined using HPLC UV/PDA method. In all samples, the most common was methanesulfinothioicacid S-methyl ester (TiMe2), followed in descending order methanesulfinothioicacid S-2-propenylester/ 2-propenesulfinothioicacid S-methyl ester (TiMeAl/TiAlMe), 2-propeniltiosulfinat (TiAl2), 2-propenesulfinothioicacidS- 1-propenylester/ 1-propenesulfinothioicacid S-2-propenylester (TiPeAl/TiAlPe), methanesulfinothioicacid S-1-propenylester/ 1 –propenesulfinothioic acid S-methy 1 ester (TiMePe/TiPeMe) and unidentified compound. After mechanical damage, mass fraction TiMe2 was increased till 11 min, while other OSC were decresed till 8 min, followed by partly degradation. The most stable during the thermal treatment was TiMe2, which had the mass fraction during the frying increased, and during the blanching slightly decreased. In the same time, the thermal treatment (frying and blanching) had influence on significantly decrease of mass fraction of others OSC. During the storage of garlic water extract in the 15 days period, the most stable was TiMe2, and after 6 day of storage mass fraction was decreased for 25%. Others OSC were significantly degradatet after 3 days of storage (20-30%), and the most unstable was alicin. |