Tulip petal as a novel natural food colorant source: Extraction optimization and stability studies

Production of food ingredients from natural sources has attracted a great attention since people tend to consume foods prepared with natural additives. In the present study, potential usage of tulip petal waste was investigated to produce alternative food colorants. This study involves three parts: (i) solvent optimization (ethanol and water), (ii) process optimization (temperature and time) for anthocyanin extraction and (iii) determination of stability of anthocyanins extracted under optimum conditions determined with respect to pH and temperature. Optimum solvent was found as 35% ethanol and 65% water using mixture design. Response surface methodology was applied to determine optimum extraction process for obtaining maximum anthocyanin amount which was extracted at 54 degrees C for 116 min. Stability tests were perfomed to determine stability of anthocyanins at different temperatures (60-90 degrees C) and pH levels (2,4 and 6). An increase in temperature and pH levels caused an increment in the degradation kinetics of the anthocynains. The results of the present study highlighted that tulip petal wastes could be utilized as a novel natural source for the recovery of the natural food colorant. (C) 2016 Elsevier B.V. All rights reserved.