Abstract
In order to improve physical and chemical properties of dough produced from wheat flour of suboptimal quality (protein content 10.7% dry basis, dough energy 4.0 cm2), optimal doses of ascorbic and citric acid were evaluated using a response surface methodology and desirability function. The paper brings the analysis of the main effects as well as their interactions. The effect of organic acids was evident in relation to pH lowering and decrease in free thiol groups, which consequently changed the physical properties of dough (increased dough energy, extensibility and resistance). The well known oxidative effect of ascorbic acid which is manifested as increase in dough energy and resistance, was enhanced by the addition of citric acid i.e. their synergistic action. Contribution of citric acid was the donation of hydrogen ions which changed the pH, lowered the content of free -SH groups and increased protein aggregation. Ascorbic acid individually significantly increased energy (linear regression coefficient b1 = 4.010-4) but higher effect was exerted by the addition of ascorbic and citric acid mixture as seen through higher interaction regression coefficient (b12 = 0.076). Dough resistance was significantly affected only by ascorbic acid due to its oxidizing action whereas dough extensibility was affected by both acids (main effects) at all applied doses and their mixtures. The effect on dough extensibility depends on the dose of acids but resistance decreased with quadratic increase of acid doses. Second-order polynomials were used in modeling of responses (dough energy, resistance and extensibility) which showed a good fit with experimental data as shown by high values of the coefficients of determination R2 for energy, resistance and extensibility (0.953, 0.976 and 0.996, respectively). Based on F value, it could be concluded that the model gave good prediction of experimental data while p-values for all responses showed that the models were significant at significance of 90%. The obtained models were used to optimize the doses of ascorbic and citric acid in order to maximize dough energy and extensibility. Significant increase of dough energy by 4.7 times and extensibility by 1.5 times was achieved by the set of optimum conditions of 97 mg/kg citric and 100 mg/kg ascorbic acid. The obtained results are applicable in semi-industrial and industrial facilities for flour processing.
Highlights
Činjenice da limunska kiselina u prisustvu soli ima pozitivan efekat na osobine testa [33] i da u kombinaciji sa askorbinskom kiselinom doprinosi proširenju asortimana proizvoda od durum brašna [34] podstakla je dalja istraživanja u pravcu analize njenog delovanja, u smeši sa askorbinskom kiselinom, na pšenično testo od brašna sa niskim sadržajem proteina i izrazito niskom energijom
U farinografskoj mesilici po proceduri za izradu testa [39] formirano je testo konzistencije od 500 Fj
Za vreme rastezanja menja, za vrednost otpora testa se uzima visina krive na 5 cm od početka rastezanja i izražava se u Brabenderovim jedinicama (Bj)
Summary
Organske kiseline imaju značajnu funkciju u pšeničnom testu, među kojima je najvažnija L-askorbinska kiselina (E300) koja ima ulogu oksidacionog sredstva. S obzirom na to da proteini u pšeničnom testu imaju značajnu ulogu u formiranju strukture i određivanju biohemijskih i fizičkih osobina, opravdano je ispitivanje delovanja organskih kiselina u jednom tako složenom viskoelastičnom sistemu kao što je pšenično testo. Činjenice da limunska kiselina u prisustvu soli ima pozitivan efekat na osobine testa [33] i da u kombinaciji sa askorbinskom kiselinom doprinosi proširenju asortimana proizvoda od durum brašna [34] podstakla je dalja istraživanja u pravcu analize njenog delovanja, u smeši sa askorbinskom kiselinom, na pšenično testo od brašna sa niskim sadržajem proteina i izrazito niskom energijom. Nakon definisanja modela koji opisuje i predviđa glavne efekte i interakciju posmatranih organskih kiselina sprovešće se optimizacija koncentracije askorbinske i limunske kiseline s ciljem postizanja maksimalnog efekta povećanja energije i rastegljivosti testa korišćenjem funkcije poželjnosti
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
