Suitability of endophite yeasts from the skin and flesh of the podang mango (Mangifera lndica L.) as leavening agents for bread

Yeast is a leavening agent used to aid the fermentation process in bread making, by producing ethanol, as well as carbon dioxide, to improve the aroma, and increase the dough's volume, respectively. In Indonesia, the yeast used in bread making is imported. Thus, there is a need for homegrown alternatives. This study, therefore, aims to obtain yeast isolates with the capacity to act as bread leavening agents from the skin and flesh of Mangifera indica var. Podang. In this study, a total of three endophytic isolates, YDM-1, and YDM-3, from the fruit's flesh, as well as YKM-1 from the skin, were obtained. YDM-1 and YKM-1 were identified macroscopically and microscopically as Ascomycota class and Hemiascomycetes sub-class. In comparison, YDM-3 was identified as Ascomycota class and Archiascomycetes sub-class. Subsequently, the isolates were subjected to carbohydrate fermentation, 50% glucose tolerance, flocculation, hydrogen sulfide compound, temperature tolerance, and ethanol tolerance analyses. The three isolates have met the criteria for leavening yeast. YDM-3 and YKM-1 are able to produce a similar increase in the volume of bread dough commercial yeast, with an incubation period of 12 hours. Meanwhile, YKM-1 produced the best aroma as well as the best potential in developing bread and is, therefore, suitable to be used as commercial yeast.