Abstract | Rogač (Ceratonia siliqua L.) je zimzeleno stablo iz porodice mahunarki koje se uglavnom uzgaja na području Mediterana. Plod rogača (mahuna) ima visoku nutritivnu vrijednost, a zahvaljujući visokom udjelu prehrambenih vlakana i fenolnih spojeva, posjeduje brojne dodatne pozitivne učinke na zdravlje. Proteini su makronutrijenti s brojnim fiziološkim ulogama, a s obzirom da organizam ne može sam sintetizirati sve aminokiseline od kojih se oni sastoje, neophodno ih je unositi prehranom. Stoga je cilj ovog istraživanja bio odrediti udio probavljivih proteina, kao i postotak probavljivosti u uzorcima brašna rogača prikupljenog na 14 različitih lokaliteta s područja obale i otoka srednje i južne Dalmacije. Također, ispitan je i utjecaj antinutritivnih faktora, kao što su prehrambena vlakna i fenolni spojevi (naročito tanini), na probavljivost proteina. Određivanje probavljivih proteina u uzorcima brašna rogača provedeno je kombinacijom modificirane metode po Kumagai-u kojom je simulirana gastrointestinalna digestija i metode po Kjeldahlu. Rezultati istraživanja su pokazali da je udio probavljivih proteina u brašnu rogača relativno nizak (1,749 - 3,228 g/100 g originalnog uzorka) te da vrijednosti značajno variraju ovisno o lokalitetu, s najvećom varijacijom od 84,563 %. Također, lokalitet je imao vrlo značajan utjecaj i na probavljivost proteina pri čemu je utvrđena najveća varijacija od 102,067 %. Usporedbom probavljivosti proteina s udjelom ukupnih, odnosno topljivih prehrambenih vlakana utvrđena je slaba do umjerena korelacija (r = 0,334, odnosno r = 0,472), dok je usporedbom s udjelima ukupnih fenolnih spojeva (r = 0,505) i tanina (r = 0,615) pronađena umjerena do dobra korelacija. Unatoč njihovim antinutritivnim učincima, prehrambena vlakna i fenolni spojevi s njihovim protektivnim učincima na zdravlje čine rogač namirnicom koja se sve više preporučuje kao dio uravnotežene prehrane. |
Abstract (english) | Carob (Ceratonia siliqua L.) is an evergreen tree of the Fabaceae family, cultivated mainly in the Mediterranean area. Carob pod has a high nutritional value and, because of the high share of dietary fiber and phenolic compounds, has a number of additional positive effects on human health. Proteins are macronutrients with numerous physiological roles and considering that human body can not synthesize all the amino acids of which they consist, they must be obtained from the diet. The aim of this study was to determine the content of digestible proteins and the percentage of digestibility in carob flour samples collected at 14 different locations in the coast and islands of central and southern Dalmatia. Also, it was examined the influence of antinutritive factors, such as dietary fiber and phenolic compounds (especially tannins), on protein digestibility. The share of digestible proteins in carob flour was determined by combining the modified Kumagai method, which simulated the gastrointestinal digestion, and the Kjeldahl method. The results showed that the share of digestible protein in carob flour is relatively low (1.749 - 3.228 g/100 g of original sample) as well as the values vary significantly depending on the location, with a maximum variation of 84.563 %. Also, the location has had a very significant effect on protein digestibility and it is determined a maximum variation of 102.067 %. Comparing protein digestibility with a content of total and soluble dietary fiber, it was found a small to intermediate correlation (r = 0.334, r = 0.472) and while comparing protein digestibility with a content of total phenolic compounds (r = 0.505) and tannins (r = 0.615), there was an intermediate to good correlation. Despite their antinutritive effects, dietary fiber and phenolic compounds with their protective effects on health make carob a food highly recommended as part of a balanced diet. |