201. Antioksidativne lastnosti kruha, obogatenega z dodatkom kaljenih pšeničnih zrn
- Author
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Porenta, Karmen and Terpinc, Petra
- Subjects
antioksidanti ,Triticum aestivum ,pšenica ,phenolic compounds ,Folin-Ciocalteu ,udc:633.111:543.637:547.56 ,germinated wheat grains ,obogaten kruh ,analytical methods ,enriched bread ,antioxidants ,wheat ,kaljena pšenična zrna ,ABTS ,fenolne spojine ,analizne metode ,DPPH - Abstract
V okviru diplomskega dela smo ugotavljali, kako različni dodatki kaljenih pšeničnih zrn (KPZ) vplivajo na antioksidativne lastnosti kruha. Prvi del poskusa je zajemal pripravo ekstraktov fenolnih spojin (FS) iz predhodno homogeniziranih in liofiliziranih vzorcev kruha z 0 %, 5 %, 15 % in 30 % dodatkom KPZ. Ekstraktibilne FS smo iz kruha pridobili s pomočjo metanola, medtem ko smo vezane FS sprostili iz celičnega matriksa šele po predhodni bazični hidrolizi. Za določanje vsebnosti FS smo uporabili metodo Folin-Ciocalteu (FC), za določanje vsebnosti antioksidantov pa metodi ABTS in DPPH. Z vsemi tremi metodami smo prišli do podobnih rezultatov. V kruhu s KPZ so ne glede na količino dodatka, prevladovali vezani antioksidanti. 15 % dodatek KPZ je vodil v znatno povečanje reaktivnosti ekstraktibilnih (1,9-krat pri metodi FC, 2,6-krat pri metodi ABTS ter 7,4-krat pri metodi DPPH) in vezanih antioksidantov (2,5-krat pri metodi FC in 1,6-krat pri metodi ABTS). Obogatitev kruha s KPZ je praviloma pomenila večji absolutni prirast vezane frakcije in večji relativni prirast proste frakcije antioksidantov. Vsebnost spojin z antioksidativnim delovanjem ni naraščala sorazmerno s količino dodanih KPZ, 30 % dodatka KPZ nismo opravičili. Within the diploma thesis we have studied how different amounts of added germinated wheat grains (KPZ) affect the antioxidant properties of bread. First, the preparation of phenolic compounds (FS) extracts from pre-homogenized and lyophilized bread samples with 0%, 5%, 15% and 30% addition of KPZ were performed. Extractable FS were obtained from bread using methanol, while bound FS were released from the cell matrix after alkaline hydrolysis. The Folin-Ciocalteu (FC) method was used to determine FS content, and the ABTS and DPPH methods for antioxidant determination. Similar results were obtained with all three methods. Bound antioxidants predominated in bread with KPZ, regardless of their amount. A 15% addition of KPZ resulted in considerable enlargement of reactivity of extractable (1.9-fold in the FC method, 2.6-fold in ABTS method and 7.4-fold in DPPH method) and bound antioxidants (2.5-fold in the FC method and 1.6-fold in the ABTS method). Enrichment of bread with KPZ resulted in higher absolute increment of bound and higher relative increments of free antioxidants. The content of the compound with antioxidant activity did not increase in proportion to the amount of added KPZ, supplement of 30% KPZ was not justified.
- Published
- 2020