Utjecaj skute i tofua na fenole djevičanskog maslinovog ulja određene Fast Blue BB testom
| Autor: | Franjković, Doris |
|---|---|
| Přispěvatelé: | Koprivnjak, Olivera, Gobin, Ivana, Majetić Germek, Valerija |
| Jazyk: | chorvatština |
| Rok vydání: | 2023 |
| Předmět: | |
| Popis: | Djevičansko maslinovo ulje tradicionalno se koristi kao naljev za konzerviranje različitih vrsta namirnica. Pri tome može doći do migracije i međusobnih interakcija sastojaka kao što su npr. proteini iz skute i tofua te fenolne tvari iz djevičanskog maslinovog ulja, uz promjene u nutritivnim, senzorskim i funkcionalnim svojstvima obiju skupina tvari. Kao indirektni pokazatelj interakcija, u ovom su radu istražene promjene udjela ukupnih fenola djevičanskog maslinovog ulja tijekom njegovog višednevnog kontakta sa skutom i tofuom. Ukupni fenoli određeni su kolorimetrijskom metodom i reagensom visoko specifičnim za ove tvari. Simuliran je tradicionalni postupak čuvanja komadića skute i tofua u naljevu (7, 14 i 21 dan u hladnjaku, uz omjer masa materijal/ulje 1,3). Udio vode u ulju porastao je s početnih 0,06 % na konačnih 0,23 % (kontakt sa skutom) te 0,67 % (kontakt s tofuom). Pokazatelji hidrolitičkog i oksidacijskog kvarenja ulja blago su se ali statistički značajno smanjili, vjerojatno zbog njihovog amfifilnog karaktera i porasta udjela vode u ulju. Do značajnog smanjenja ukupnih fenola u ulju došlo je već nakon sedam dana čuvanja pri 2 ± 2 °C (za 48 % pod utjecajem skute i za 53 % pod utjecajem tofua), a nakon 21 dana za 65 % (utjecaj skute) te za 73 % (utjecaj tofua). Utvrđen je logaritamski pad udjela fenola pod utjecajem tofua (R2 = 0,96) te čvrsta negativna linearna povezanost omjera masa tofu/ulje i udjela fenola u ulju tijekom sedam dana čuvanja pri 6 ± 2 °C (r = -0,98). Razlike između materijala vjerojatno proizlaze iz različitih karakteristika i udjela proteina u suhoj tvari, te različitih udjela vode i drugih sastojaka u matriksu hrane. Rezultati pružaju korisne informacije za evaluaciju tradicionalnih postupaka čuvanja hrane u djevičanskom maslinovom ulju kao naljevu, budući da ukazuju na dinamiku interakcija fenola i proteina koje mogu rezultirati smanjenjem bioraspoloživosti i biodostupnosti obiju skupina tvari. Virgin olive oil is traditionally used as a marinade for the preservation of various types of food. This can lead to migration and mutual interactions of ingredients such as proteins from whey cheese and tofu and phenolic substances from virgin olive oil, with changes in the nutritional, sensory and functional properties of both groups of substances. As an indirect indicator of interactions, this work investigated changes in the proportion of total phenols of virgin olive oil during its several-day contact with whey cheese and tofu. Total phenols were determined using a colorimetric method and a highly specific reagent for these substances. The traditional procedure of keeping pieces of whey cheese and tofu in an infusion was simulated (7, 14 and 21 days in the refrigerator, with a mass ratio of material/oil of 1.3). The proportion of water in the oil increased from the initial 0.06 % to the final 0.23 % (contact with whey cheese) and 0.67 % (contact with tofu). Indicators of hydrolytic and oxidative deterioration of oils decreased slightly but statistically significantly, probably due to their amphiphilic character and the increase in the proportion of water in the oil. A significant reduction of total phenols in the oil occurred after only seven days of storage at 2 ± 2 °C (by 48 % under the influence of whey cheese and by 53 % under the influence of tofu), and after 21 days by 65 % (influence of whey cheese) and by 73 % (influence of tofu). A logarithmic decrease in the proportion of phenol under the influence of tofu (R2 = 0,96) and a strong negative linear relationship between the mass ratio of tofu/oil and the proportion of phenol in oil during seven days of storage at 6 ± 2 °C (r = -0,98) were determined. The differences between the materials probably stem from different characteristics and the proportion of protein in the dry matter, and different proportions of water and other ingredients in the food matrix. The results provide useful information for the evaluation of traditional food preservation procedures in virgin olive oil as an infusion, since they indicate the dynamics of phenol-protein interactions that can result in a decrease in the bioaccessibility and bioavailability of both groups of substances. |
| Databáze: | OpenAIRE |
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