مقالات رزومه پریسا عطایی

Occurrence and growth of fungi may cause spoilage and reduce dramatically quality and safety of white cheeses. A considerable interest both in the industry and scientific research has developed on the preservation of foods by the use of essential oils (EO) to effectively retard fungi growth and mycotoxin production. Therefore, the aim of this work was to investigate the chemical compositions and antifungal properties of several Iranian EOs against fungi contaminating Iranian white cheese. In this study, the EOs including Trachyspermum ammi, Satureja hortensis and Mentha piperita were used. The chemical compositions of EOs were characterized using GC-MS. Antifungal properties of EOs against isolated fungi was determined by disk diffusion agar, minimum inhibitory concentration (MIC), and minimum fungicidal concentration (MFC). According to the results from disk diffusion tests, the most sensitive fungi against all EOs was Trichoderma harizanum. In this regard, Paecilomyces variotii, Aspergillus niger, and Aspergillus oryza were highly resistance against all EOs. Also, The results of MIC and MFC indicate that the most sensitive fungi to all three EOs of T. ammi, S. hortensis and M. piperita was T. harizanum with MIC values of 0.281, 0.250 and 0.562 µL/mL, respectively, and its MFC values was 0.562, 0.562 and 1.125 µL/mL, respectively. Also, among the studied EOs, T. ammi and S. hortensis showed the highest antifungal activity, while M. piperita showed lower antifungal properties in compared to the other two EOs. Based on the results, it can be said that S. hortensis and T. ammi EOs have good antifungal activities and can be used in food industries, medical pharmacology, health affairs, and antifungal elements.

Cheese is one of the valuable dairy products that has a significant role in feeding most people in society. During or after the production process, cheeses may become contaminated with moulds, which can endanger the health of the product and reduce its marketability. Cheese is one of the foods that has the suitable conditions for the growth of fungi. The purpose of this study was to isolate and identify the contaminants of ultrafiltration (UF) cheeses offered in Fasa city. For this purpose, 110 samples of cheese cans from different factories were randomly collected from the market and kept both open and closed. After growth, moulds were identified morphologically and molecularly. The results showed that the highest contamination of open cheeses was related to Penicillium, followed by Aspergillus, Paecilomyces and Trichoderma. In closed cheeses, Byssochlamys spectabilis was the most contaminated mould. During this study, for the first time in Iran, this type of fungus was isolated and identified.

Every year during marine fishing, some species that are caught are not suitable for human consumption, and they are known as surplus fishing or low consumption, which is an important factor in wasting these rich resources. Therefore, it is necessary to set arrangements to use such species for human consumption, including the production of surimi. In this regard, additives such as gums can be used to reform and improve the properties of surimi. Therefore, in this study, the possibility of producing surimi from Chacunda gizzard shad was investigated, and the effect of Konjac gum on the physicochemical and textural properties of the product produced from this type of fish was evaluated. In this study, Chacunda gizzard shad was purchased freshly from the dock in Local market in Bushehr (IRAN) and immediately transferred to the laboratory after being placed in an ice chamber. After preparing surimi, Konjac gum in concentrations of 0.25, 0.50, and 0.75 % (w/w) was added directly to the surimi. Then, to prepare the surimi gel, the samples were first placed in a water bath at 25 ° C for 3 hours and then heated at 90 ° C for 20 minutes. After cooling the samples with ice water, the necessary tests were performed on them. The produced surimi was evaluated in terms of chemical composition, water holding capacity, and color factors, and the study of tissue properties and sensory evaluation of the produced gels was performed and compared with the control sample (without gum). Based on the results, the percentage of ash, protein, and fat in the treatments did not change significantly compared to the control sample (p>0.05). As the contraction level of Konjac gum increased, the amount of moisture and water holding capacity of the surimi samples increased significantly. The lightness level (L*) of the surimi and surimi gel increased significantly with the addition of Konjac. The control sample and the sample containing 0.25% of Konjac in the surimi of Chacunda gizzard shad showed more yellowness and redness than other treatments. But in the resulting gel, the amounts of redness and yellowness between treatments were not significant. By increasing the concentration of Konjac in surimi gel, the parameters of texture (firmness, cohesiveness, adhesiveness, springiness, chewiness), breaking force and deformation increased significantly compared to the control sample. Sensory evaluations also showed that the panelists assigned the highest score to the 0.75 % Konjac treatment for surimi gel from the Chacunda gizzard shad. Based on the findings of the present study, it was found that Chacunda gizzard shad has the potential to produce surimi, and by adding Konjac gum, its properties can be improved.

Every year during marine fishing, some species that are caught are not suitable for human consumption and they are known as surplus fishing or low consumption, which is an important factor in wasting these rich resources. Therefore, it is necessary to set arrangements to use such species for human consumption, including the production of surimi. The surimi industry mainly uses Alaska pollock fish as the main source for surimi production. However, due to the increase in the world’s population and partly the depletion of the fish stocks, followed by a reduction in the surimi production of Allaska Pollock fish (due to restrictive fishing laws), the need to use new species is considered urgent. In this regard, additives such as gums can be used to reform and improve the properties of surimi. Therefore, in this study, the possibility of producing surimi paste and gel from Lizardfish and Talang Queenfish was investigated and the effect of Konjac on the physicochemical properties of the product produced from these two types of fish was evaluated.

In this study, Talang Queenfish and Lizardfish with approximate weight of 225.9±33.6 and 275.9±24.4 g and average size of 15.1±2.4 and 17.3± 2.6 cm, respectively, were purchased freshly from the fish market. After preparing surimi paste from both types of fish, Konjac gum in concentrations of 0.25, 0.50 and 0.75 % (w/w) was added directly to the surimi paste. Then to prepare surimi gel, first, the samples were placed in a water bath at 25 ° C for 3 hours for setting and then cooked at 90 ° C for 20 minutes. After that, the prepared gels were cooled in iced water immediately. The produced paste and gel were evaluated in terms of chemical composition, water holding capacity and color factors. Texture and sensory characteristic were assessed on the produced gels of both types of fish and compared with the control sample (without gum).

According to the results, the yield of Lizardfish was 28% and Talang Queenfish was 22%. It seems that the larger size of Lizardfish has been effective in its higher yield than Talang Queenfish. Based on the results, the percentage of ash, protein and fat in the treatments did not change significantly compared to the control sample. Also, there was no significant difference between the two types of fish in the amount of mentioned factors (p>0.05). As the contraction level of Konjac gum increased, the amount of moisture and water holding capacity of the paste samples of both fish increased significantly, which is due to the absorption and binding of water by the Konjac hydrocolloid. The lightness level (L*) of the surimi paste and gel of both types of fish increased significantly with the addition of Konjac, which is related to the increase in water content in the samples. The lightness of the surimi paste and gel of Lizardfish was higher than that of Talang Queenfish, which is due to the presence of more pigments in the Talang Queenfish meat. Control Sample and treatment of 0.25% of Talang Queenfish surimi paste showed more yellowness and redness than Lizardfish, but in the resulting gel, their values were reduced, indicating that the formation of gel structure by Konjac gum and binding to the proteins covered the yellowness and redness of the samples. By increasing the concentration of Konjac in surimi gel of both fish the parameters of texture (firmness, cohesiveness, adhesiveness, springiness, chewiness) breaking force and deformation increased significantly compared to the control sample. Also, the results showed that the surimi gel from Lizardfish has higher firmness, cohesiveness and strength than Talang Queenfish. Sensory evaluations showed that the panelists assigned the highest score for the surimi gel from Lizardfish to the 0.5% treatment and for the Talang Queenfish to the 0.75% treatment of Konjac. Based on the findings of the present study, it was found that surimi gel from Talang Queenfish has a lower quality than Lizardfish, but with the addition of Konjac gum, its properties can be improved.

In this study, non-market sizes of Ilisha fish, which are less welcomed by consumers, were used to produce surimi and the effect of Konjac gum on the physicochemical properties of the product produced from this type of fish was investigated. For this purpose, different amounts of Konjac gum in concentrations of 0.25, 0.50 and 0.75 % (w/w) were added to the surimi samples of Ilisha fish and compared with the control sample (without gum). Surimi and the produced gel were evaluated in terms of chemical composition, water holding capacity and color factors, and textural properties and sensory evaluation were performed on the produced gels. The results showed that by adding Konjac gum to surimi samples and surimi gels, the amount of lightness (L*) decreased compared to the control sample while the moisture and water holding capacity of the samples increased significantly (p<0.05). By increasing the concentration of Konjac in surimi gel, the parameters of texture (firmness, cohesiveness, adhesiveness, springiness, chewiness) increased significantly compared to the control sample. Sensory evaluations also showed that the panelists assigned the highest score to the 0.5 % Konjac treatment for surimi gel from the Ilisha. Based on the findings of the present study, it was found that Ilisha has the potential to produce surimi and by adding Konjac gum, its properties can be improved.