Determination of antioxidant potential of dehydrated soup enriched with lyophilized mushroom extracts

Abstract

The aim of this study was to determine the antioxidant potential of dehydrated soup enriched with different types of lyophilized mushroom extracts. Three mushroom species were collected from the Republic of North Macedonia: Suillus granulatus, Coriolus versicolor and Fuscoporia torulosa. After their determination and drying, aqueous and ethanolic extracts (50% EtOH) were prepared. Moreover, both extracts were lyophilized showing high antioxidant potential, determined through the ability to capture free DPPH radicals (73.38–81.60%) and the conjugated diene method (69.25– 77.06%). Both types of lyophilized extracts were added in industrially produced dehydrated vegetable soup in order to improve its quality properties, as well as the biological activity. Thus, ten samples of dehydrated soups were produced. Higher values for all antioxidant tests were obtained in all tested soup samples enriched with lyophilized mushroom extracts, compared to the control sample. According to the DPPH radical test (54.14–61.41%) and the ability to chelate iron ions (36.68–43.99%), higher values were obtained in soups enriched with lyophilized aqueous extracts, while the method of conjugated dienes showed higher values in soups enriched with lyophilized ethanolic extracts (47.27–60.60%). From the aspect of product traceability during storage, it can be noticed that in all antioxidant tests the values were constant until the 30th day after production, and then they decreased minimally until the 45th day after production. Namely, on the 45th day after production, the largest decrease in antioxidant activity of soups enriched with lyophilized aqueous extracts was observed with the conjugated diene method (43.17–54.79%). The antioxidant activity of all tested samples on 0th, 15th and 30th day after production differed statistically significant (p<0.05) compared to 45th, 60th and 90th day after production. Therefore, it can be concluded that the obtained product showed certain antioxidant potential which is significantly higher compared to the control sample.