Investigation of the antifungal effects of natural antimicrobial agents during fermentation and storage period in traditionally produced hardaliye
Project no. 20992 · Status: Kapanmış · 2019
Summary
<p>Hardaliye is a non-alcoholic traditional fermented beverage from Thrace region of Turkey that has a characteristic taste and odor produced by using grapes, mustard seeds, sour cherry leaves and sodium benzoate. One of the most critical points in hardaliye production is the prevention of alcohol formation by inhibiting the growth of yeast. Sodium benzoate considered as a food additive is added for the inhibition of yeast growth. In this project, the effect of using various plant materials as an alternative to sodium benzoate for the inhibition of yeast growth in hardaliye in order to ensure the production of additive-free hardaliye is investigated. Antifungal effects of water extracts of linden flower, quince leaves, green tea leaves, mulberry leaves, horseradish, sour cherry leaves, mustard seed and sodium benzoate on <em>S. cerevisiae</em>were investigated. Different hardaliye were produced using the selected test materials and microbiological and chemical analyzes were carried out during fermentation and storage. Only mustard seed extract had inhibitory and fungicidal effect at 25 mg/ml on <em>S. cerevisiae</em> among the tested plant materials extracts, the antifungal effect of mustard seed extract increased when used in combination with grape juice. The total phenolic content of the hardaliye samples were in the range of 2119.26-8653.33 mg GAE/L, and the antioxidant activities were in the range of 30.24%-93.15%. It was determined that the use of plant materials increased the total phenolic contents and antioxidant activities of hardaliye samples significantly. On the other hand, plant materials did not have an inhibitory effect on lactic acid bacteria and yeast growth at the used levels (1%). For this reason, the survival of <em>S. cerevisiae</em> as a test culture in grape juice containing plant materials were investigated. It was reported that the numbers decreased below the detection limit (<1 log CFU/ml) after 1 day in the grape juice samples containing horseradish (5%), mustard seeds (1.5%) or sodium benzoate (0.1%). As a result of this study, it was indicated that the use of mustard seeds at increased concentrations or horseradish have the potential to be used in the production of hardaliye as an alternative to sodium benzoate.</p>