Effect of Drying Method on the Production of Dehydrated Sourdough Starter from Fermented Papaya (Carica papaya L)

Yeast is a leavening agent used in bread-making that contains microorganisms of the Saccharomyces cerevisiae species. The use of yeast in bread-making is known for its practicality and ease, but yeast intolerance often occurs. As an alternative, natural yeast can be used to address this problem. Natural yeast has several benefits, such as enhancing flavor and aroma, prolonging the shelf life of bread, improving digestibility, maintaining bread softness for an extended period, and being free from additional chemical additives. However, natural yeast also has some disadvantages, such as a moist and brittle texture, which leads to a relatively shorter storage time. Therefore, this study aimed to investigate the impact of different drying techniques on natural yeast derived from fermented papaya fruit water. The drying techniques employed were air-drying for five days, sun drying for five days, and oven drying at 40°C for 48 hours. The best-dried yeast was obtained through the 5-day air-drying process, with a moisture content of 13.1%, nitrogen content of 2.07%, lactic acid bacteria colony count of 9.50 × 103 CFU/g, and an average preference rating of 3.92 for appearance, aroma, and color by the panelists. Furthermore, the dried yeast was successfully reactivated, with a volume expansion of 3 times from the initial height of 3 cm to 9 cm.