Optimizing Sourdough Process for the Production of Honey and RoseLike Aromas in Breads

Background and Objective:Fermentation is one of the best methods for in-situgeneration of aromas in breads.However, generating desirable flavors needs controlling several effective factors. In this study,optimal conditions for the production of honey and rose-like aromas were investigated by fitting a quadratic model using response surface method. To the best of the authors’ knowledge, no study has used this method for the high-efficiency production of flavor compounds in sourdough.Material and Methods:In the present study, headspace solid-phase microextraction-gas chromatography mass spectrometrywas used to demonstrate ability of Kluyvero-mycesmarxianusand Leuconostoc mesenteroidesco-culture to produce 2-phenyl ethyl acetate and 2-phenyl ethyl alcohol in sourdough. Therefore, experiments were developed using response surface method and six parameters of dough yield, temperature, time,fructose, phenylalanine and bran proportions. Volatiles were collected from sourdough using headspace solid-phase microextractionmethod, followed by measuring the extracted volatile compounds using gas chromatograph connected to a mass selective detector.Results and Conclusion:Results suggested thatfermentation was optimum at 25 °Cfor 66.5 h with dough yield, 400;fructose,6%w v-1;phenylalanine, 0.3% w v-1and bran, 20% w w-1for the production of rose and honey-like aromas with high efficiency(2-phenyl ethyl alcohol127.1 mg l-1and 2-phenyl ethyl acetate70.7 mg l-1). Assessment of the baking and storage effects on the selected aroma compounds showed that although sharp decreases occurred in their concentrations due to the oven temperature, they were still detectable in the bread after 3 daysof storage.Based on the optimized model, it can be concluded that increasing time and decreasing fermentation temperature led to the strengthening of aroma production. Furthermore, phenylalanine and fructose strongly affected development of the target aromas.Conflict ofinterest:The authors declare no conflict of interest