Ultrasound-assisted extraction of phenolic compounds from mango (Mangifera indica cv. Chok Anan) peel and its inhibitory effect on enzymatic browning of potato puree / Chotika Jirasuteeruk, Chockchai Theerakulkait.
Sažetak

Enzymatic browning is a serious quality deterioration of fresh-cut fruits and vegetables. Recently, consumers and fruit and vegetable industrial processors have demanded the use of natural antibrowning agents to replace the use of chemicals. Mango (Mangifera indica cv. Chok Anan) peel was prepared in the form of mango peel liquid nitrogen powder. This included extraction by ultrasound or ultrasound combined with stirring. The total phenolic content of mango peel liquid nitrogen powder extract (further in the text: mango peel extract) was the highest after the extraction for 15 min using ultrasound followed by stirring for 15 min. The browning value of potato puree treated with mango peel extract was lower, while its L* value and the hue angle were larger than of samples treated with ascorbic or citric acids during storage for 6 h. Mango peel extract had a competitive inhibitory effect on potato polyphenol oxidase (PPO), which was larger than either ascorbic or citric acid. Its IC50 value was 0.3 mg/mL. Mangiferin, protocatechuic and gallic acid found in mango peel extract had high inhibitory effect on potato PPO, making mango peel a potential natural source of enzymatic browning inhibitor.; Enzimsko posmeđivanje ozbiljno narušava kakvoću svježe rezanog voća i povrća. U novije vrijeme, potrošači i prerađivači voća i povrća zahtijevaju da se umjesto kemijskih spojeva koriste prirodni inhibitori posmeđivanja. Iz praha kore ploda manga (Mangifera indica cv. Chok Anan) tretirane tekućim dušikom izdvojeni su polifenoli, i to ekstrakcijom potpomognutom ultrazvukom i ekstrakcijom potpomognutom ultrazvukom i miješanjem. Najveći ukupni udjel fenola u ekstraktu praha kore manga dobiven je ekstrakcijom potpomognutom ultrazvukom i miješanjem tijekom 15 min. Pri skladištenju se pirea od krumpira tretiranog prahom kore manga nakon 6 sati smanjilo njegovo posmeđivanje, dok su se svjetlina (L*) i kut promjene boje povećali u usporedbi s uzorcima pirea od krumpira tretiranim askorbinskom ili limunskom kiselinom. Ekstrakt praha kore manga imao je veći inhibicijski učinak na polifenolnu oksidazu u krumpiru nego askorbinska i limunska kiselina. Njegova vrijednost IC50 bila je 0,3 mg/mL. Mangiferin, protokatehinska i galna kiselina iz ekstrakta kore manga imali su jak inhibicijski učinak na polifenolnu oksidazu u krumpiru, pa je zaključeno da se kora manga može upotrijebiti kao prirodni inhibitor enzimskog posmeđivanja.