Total antioxidant activity (TAA) of bell pepper during prolonged storage on low temperature

Abstract

Bell pepper (Capsicum annum L.) is a vegetable known for its antioxidant content, highly important for its nutritional values. The total antioxidant activity (TAA) of pepper fruits is measured by TEAC (Trolox equivalent antioxidant capacity). This assay measures both the hydrophilic (HAA) (vitamin C) and lipophilic (LAA)(carotenoids and vitamin E) contents based on the total radical scavenging capacity and the ability of a scaverenge the stable ABTS radical (ABTS + ) described by Vinocur and Rodov (2006). Fruit were cleaned and disinfected with hot water by rinsing and brushing (HWRB) at 55?C as it is described by Fallik et all ., (1999). Tap water wash was served as control. Fruit were stored at 2?C or 7?C during 3 weeks plus 3 days at 20?C (shelf life simulation). TAA in red bell pepper, immediately after harvest, was 4.29 (0.74 lipophilic and 3,55 hydrophilic) mol TE/g fr.wt. After 3 weeks storage at 2?C, TAA in pepper with cold wash treatment was 4.14 and 3.97 TEAC mol TE/g fr.wt. in HWRB treatment. After 3weeks +3days shelf life on 20?C TAA slowly growing up and obtained content of 5.24 in cold wash and 5.16 TEAC mol TE/g fr.wt. in HWRB. This is mainly due to changes in the lipophilic activity-LAA (treatment with cold water-1.79 and 1.81 mol TE/g fr.wt. in HWRB, comparing with 0.74 mol TE/g fr.wt. on beginning of storage). Hydrophilic antioxidant activity-HAA remains practically unchanged. In fruit, stored at 7?C, pepper ripeness has been associated with carotenoids accumulation especially after shelf life, TAA was 5.33 TEAC ( LAA 2.03) mol TE/g fr.wt.Paprika (Capsicim annum L.) je povrtarska vrsta poznata po sadrzaju antioksidanata koji su vrlo znacajni za njenu hranljivu vrednost. Ukupna antioksidantna aktivnost (TAA) plodova paprike izrazava se TEAC (trolox equivalent antioksidant capacity). Ovom metodom se odredjuju i hidrohilni (vitamin C) i lipofilni sadrzaj (karotenoidi i vitamin E) zasnovani na ukupnom kapacitetu ciscenja radikala, i sposobnosti uklanjanja postojanog ABTS radikala (ABTS+) po metodi Vinokura i Rodova (2006). Plodovi su cisceni i dezinfikovani sa toplom vodom uz cetkanje i tusiranje (HWRB- hot water rinsing and brushing) na 55?C opisano u metodi Fallik et all., (1999). Plodovi prani obicnom vodom oznaceni su kao kontrolni. Plodovi su cuvani na 2?C i 7?C tokom 3 nedelje + 3 dana na 20?C (shelf-life podrazavanje uslova prodaje). TAA kod crvene paprike tipa babure neposredno nakon berbe je 4.29 (0.74 lipohilni i 3.55 hidrofilna aktivnost) mol TE/g sveze mase. Posle tronedeljnog cuvanja na 2?C, TAA kod paprika tretmanom pranja hladnom vodom je 4,14 i 3.97TEAC mol TE/g kod HWRB. Posle 3nedelje+3dana na 20?C TAA blago raste i ostvaruje sadrzaj od 5.24 u tretmanu hladnom vodom i 5.16 TEAC mol TE/g sv. mase kod HWRB. Ovo povecanje se uglavnom desava tokom promena u lipofilnoj aktivnosti (tretman sa hladnom vodom 1.79 i 1.84 ?mol TE/g sveze mase kod HWRB, u poredjenju sa 0.74 mol TE/g sv. mase pocetkom cuvanja. Hidrofilna antioksidativna aktivnost prakticno ostaje nepromenjena. Kod plodova cuvanih na 7?C zrenje je udruzeno sa akumulacijom karotenoida posebno nakon shelf-life perioda, TAA je 5.33 (lipofilna faza 2.03) ?mol TE/g sveze mase.