INHIBITION OF MOULDS ON THE SURFACE OF DRIED PERSIMMON FRUITS (Diospyros kaki L.) BY USING VARIOUS ANTIMICROBIALS AND UV-C TREATMENT
Project no. 1190 · Status: Kapanmış · 2017
Summary
In this thesis study, it was aimed to determine the antifungal effects of extracts obtained from persimmon peel and leaves and also clove oil, UV-C light and the combined use of these methods on Aspergillus, Alternaria and Rhizopus spp. isolated from the dried persimmon fruit to inhibit mould growth on the surface of the product. In this context, MIC, MFC and inhibition zones of natural antimicrobials were determined and it was revealed that the clove oil (MIC: 1.56%, v/v) has the highest antifungal effect. UV-C treatments were applied at different doses in the range of 0-18 kJ/m2 to UV-C resistant mould isolates. Rhizopus, Aspergillus and Alternaria spp. (2.24-2.59 log CFU/plate) were completely inactivated at doses of 1.2, 6, 18 kJ/m2 UV-C, respectively, whereas it has been shown that the effect of UV-C on the moulds inoculated to the dried persimmon surface was not sufficient. The combined effects of UV-C (0.6 and 3.6 kJ/m2) and clove oil (1.56 and 3.2%) were also investigated after the treatments and during the storage period of 28 day. As a conclusion of these applications, the highest reductions in the population of Rhizopus spp., Aspergillus spp. and Alternaria spp. were determined as 1.04, 0.81 and 0.72 log, respectively. Although the high rates of mould reduction were not achieved, these applications inhibited the germination of mould spores and no incidence of mould spoilage in was observed in the samples stored for 28 days. By using these treatments, the inhibition of mould growth on the surface of dried persimmons has been achieved and also a novel and value-added product that can be preferred by consumers was also produced. Keywords: Inhibition of mould, UV-C light technology, clove oil, natural antimicrobials