Chemical Characteristics and Antioxidant Activity of Fermented Bread Saccharomyces cerevisiae YIS-3, Candida tropicalis NJM-2, and Their Combination
Nur Kusmiyati*, Kizvia Putri Enggeningtyas

Department of Food Science and Biotechnology, Faculty of Agricultural Technology, Universitas Brawijaya, Malang, Indonesia

email: nurkusmiyati[at]ub.ac.id

Abstract

Fermentation is a key process in bread making that not only affects texture and taste, but can also increase the functional value of food products. Saccharomyces cerevisiae is the most commonly used yeast in bread fermentation, but the potential of non-conventional yeasts such as Candida tropicalis and their combinations has not been studied in depth, especially in the context of increasing bioactive compounds and antioxidant activity. This study aims to evaluate the chemical characteristics and antioxidant activity of fermented bread using S. cerevisiae, C. tropicalis, and their combinations. This study used five fermentation treatments, namely without yeast (K-), fermipan (K+), S. cerevisiae (P1), C. tropicalis (P2), and their combination (P3). The chemical parameters analyzed included total acid (through titration), total sugar (phenol-sulfate method), and total phenol (Folin-Ciocalteu method). Antioxidant activity was analyzed using the DPPH method and supported by functional group characterization using FTIR. The results showed that treatment P1 gave the most optimal results in total acid (54.91%). Meanwhile, treatment (P2) produced the highest value of total sugar (50.57%), and total phenol (39.14 mgGAE/g). Treatment (P3) produced the lowest total sugar (36.36%). Antioxidant activity in all samples was very weak, with the lowest IC50 value in sample (P2) (3760 ppm), even though it contained high total phenol. The FTIR spectrum strengthens the presence of phenolic (-OH) and aromatic (C=C) groups related to antioxidant activity. Treatment with C. tropicalis in bread fermentation has the potential to increase the content of bioactive compounds and antioxidant activity, making this product a candidate for functional bread that supports health.

Keywords: antioxidant- bread- Candida tropicalis- chemical characteristics- Saccharomyces cerevisiae

Topic: Food science and biotechnology