The influence of hydroxypropyl methylcellulose-(HPMC-) beeswax (BW) composite edible coatings formulated with or without food additives with antifungal properties on physicochemical and sensory properties of plums (Prunus salicina) cv. "Friar" stored for 11 and 22 d at 1 ∘ C followed by a shelf life period of 5 d at 20 ∘ C was evaluated. Food preservatives selected from previous research included potassium sorbate (PS), sodium methyl paraben (SMP), and sodium ethyl paraben (SEP). Emulsions had 7% of total solid content and were prepared with glycerol and stearic acid as plasticizer and emulsifier, respectively. All the coatings reduced plum weight and firmness loss and coated fruit showed higher titratable acidity, soluble solids content, and hue angle values at the end of the storage period. In addition, physiological disorders such as flesh browning and bleeding were reduced in coated samples compared to uncoated controls. Paraben-based coatings were the most effective in controlling weight loss and the SMP-based coating was the most effective in maintaining plum firmness. Respiration rate, sensory flavor, off-flavors, and fruit appearance were not adversely affected by the application of antifungal coatings. Overall, these results demonstrated the potential of selected edible coatings containing antifungal food additives to extend the postharvest life of plums, although further studies should focus on improving some properties of the coatings to enhance gas barrier properties and further increase storability.

In this study, minerals required for the growth and aflatoxin production of A. flavus were determined. Then, the effectiveness of some chelating agents such as citric acid, phytic acid and ethylenediaminetetraacetic acid (EDTA) in preventing mold growth and toxin production was investigated in a fig-based medium and in two synthetic media, called Czapek-dox agar (CZA) and potato dextrose agar (PDA). A. flavus did not grow in CZA without sodium nitrate during 6-day incubation at 30 °C. The absence of the other components (magnesium sulfate, iron sulfate, potassium chloride and potassium phosphate) did not significantly (p>0.05) affect the growth of the mold. However, the mold produced significantly (p<0.05) higher amounts of aflatoxins in the media without magnesium sulfate and iron sulfate. A. flavus grew faster on fig-based medium and produced higher amounts of aflatoxins in PDA. In all media tested in this study, EDTA was found to be more effective than the other agents in controlling the growth of A. flavus. It was also effective in inhibiting the production of aflatoxins. It was determined that 1.75 mM EDTA reduced aflatoxin production up to 97% in PDA. Citric and phytic acids could inhibit the growth of the mold only in PDA. All chelating agent reduced aflatoxin production over 90% in fig-based medium. Bu çalışmada, A. flavus küfünün gelişmesi ve aflatoksin üretmesi için ihtiyaç duyduğu mineral maddeler tespit edilmiştir. Daha sonra, sitrik asit, fitik asit, etilendiamintetraasetik asit (EDTA) gibi bazı şelat ajanlarının; incir-bazlı bir ortam, Czapek-dox agar (CZA) ve patates dekstroz agar (PDA) besiyerlerinde küfün gelişmesi ve toksin üretmesini önlemedeki etkinliği araştırılmıştır. Sodyum nitrat içermeyen CZA besiyerinde 30 °C'deki 6 günlük inkübasyon süresince A. flavus küfünün hiç gelişmediği saptanmıştır. Diğer bileşenlerin (magnezyum sülfat, demir sülfat, potasyum klorür ve potasyum fosfatın) besiyerinde bulunmaması, küfün gelişimini istatistiksel olarak anlamlı bir şekilde etkilememiştir (p>0.05). Ancak magnezyum sülfat ve demir sülfat içermeyen besiyerlerinde istatistiksel olarak anlamlı düzeyde yüksek miktarlarda aflatoksin üretimi gözlenmiştir (p<0.05). A. flavus küfü, incir-bazlı ortamda daha hızlı gelişmiş ve PDA besiyerinde daha yüksek miktarda aflatoksin üretmiştir. Denenen tüm besiyerlerinde, EDTA, A. flavus gelişimini kontrol etmede diğer ajanlara göre daha etkili olmuştur. Ayrıca bu ajan, aflatoksin üretimini inhibe etmede de etkili bulunmuştur. Söz konusu ajanın 1.75 mM'lık konsantrasyonu, PDA besiyerinde aflatoksin üretimini %97'ye varan oranlarda azaltmıştır. Sitrik asit ve fitik asit küf gelişimini sadece PDA besiyerinde inhibe edebilmiştir. Denenen tüm şelat ajanları, incir-bazlı ortamda aflatoksin üretimini %90'ın üzerinde azaltmıştır.