جستجوی مقالات مرتبط با کلیدواژه "grapes" در نشریات گروه "صنایع غذایی"

The growth of fungal pathogens on the grape fruit causes a decrease in its quality and shelf life. In this study, the antifungal activity of ginger (Zingiber officinale) essential oil was investigated against fungal pathogens that cause spoilage in grape fruit. Ginger essential oil was extracted using hydrodistillation method and the content of total phenol, total flavonoid, antioxidant activity based on the inhibition of DPPH and ABTS free radicals and its antifungal activity against Aspergillus niger, Rhizopus stolonifer and Botrytis cinerea strains based on disc diffusion agar, well diffusion agar, minimum inhibitory concentration, and minimum fungicidal concentration were evaluated. The results showed that ginger essential oil has 89.80 mg GA/g total phenol and 38.60 mg QE/g total flavonoid. Its antioxidant activity against DPPH and ABTS free radicals was 73.45 and 66.53 μg/ml, respectively. The results of antifungal activity showed that A. niger and B. cinerea were the most sensitive and resistant fungal strains to essential oil, respectively, and the diameter of the inhibition zone in the disc diffusion and well diffusion agar methods, the minimum inhibitory concentration, and the minimum fungicidal concentration for the A. niger strain was equal to 13.90 mm, 14.50 mm, 8 mg/mL and 64 mg/mL, respectively. In general, ginger essential oil can be used as an antioxidant and antimicrobial agent to increase the shelf life of agricultural products.

The increase in the production and consumption of grapes in the world has increased the need for research in the field of creating conditions for further preservation of this fruit, and the lack of sensors that can provide accurate information from the production and storage process to control systems for decision-making is obvious and evident. Therefore, this study aimed to determine some characteristics of grape fruit (taste index, pH, firmness, ion leakage, ∆E, number of mold and general acceptance) stored in cold storage in the range of storage time from 0 to 60 days was measured and according to the importance Achieving these characteristics during fruit storage, a model using fuzzy logic was created as an expert system with accuracy (with a correlation coefficient greater than 0.96) and very high speed capable of predicting and determining these product characteristics only by using It was time to save it. This system was able to obtain the value of each of these studied characteristics at any desired storage time in the range of 0 to 60 days with very high accuracy and in a fraction of a second. On the other hand, it was found that with increasing storage time, the amount of taste index, pH, number of molds, ∆E and ionic leakage of the samples increased, but the degree of hardness and overall acceptance decreased.

In this research, due to the lack of a study on the modeling of the storage conditions of grape fruits coated with maltodextrin containing potassium nanocarbonate and pyracantha extract using the fuzzy-neural inference system (ANFIS), different storage times (zero to 60 days), concentration Potassium nanocarbonate (zero to 2%) and concentration of pyracantha extract (zero to 1.5%) used in edible coating as input and the amount of Brix, the percentage of dropping berry, the amount of malondialdehyde, the browning of the grapes cluster, aroma and taste of samples were considered as output. Three Gaussian, triangular and trapezoidal membership functions with 2-2-2 and 3-3-3 membership functions were investigated. The results showed that trapezoidal function with 3-3 membership function and Gaussian function with 3-3 membership function were selected as the best model for Brix output variable and percentage of dropping berry, respectively. finally, triangular model with 3-3 membership function was selected for cluster browning and malondialdehyde variables. On the other hand, the results indicated that with the increase in storage time, the amount of Brix, the percentage of dropping berry, malondialdehyde and cluster browning increased in all samples, but the amount of aroma and tast of the samples decreased. the use of coating containing potassium nanocarbonate and pyracantha extract caused the speed of these changes to decrease. In the end, it can be said that the high correlation coefficients between the laboratory results and the model outputs indicate the acceptable accuracy and usability of these models in controlling the storage conditions of grape fruits coated with maltodextrin containing potassium nanocarbonate and pyracantha extract.

The use of chemical compounds to prevent corruption and increase the shelf life of agricultural products, including grapes, has many applications. Due to the harmful effects of these compounds on human health and also the tendency of people to use organic products, today the use of low-risk and alternative methods has increased. The use of antimicrobial, antibacterial and antifungal compounds, such as natural essential oils, can be a good way to increase the shelf life of crops. In this study, the effect of thyme essential oil on increasing the shelf life of Fakhri cultivar grapes by two methods of immersion (direct contact) and fumigant (indirect contact) in concentrations (0, 150, 300 and 450 μl / l) In the cold storage with a temperature of 1±2° C and a relative humidity of 90% was tested for 60 days. Traits such as percentage of changes in fruit weight, titratable acidity, total soluble solids, sensory evaluation including fruit texture firmness, Smell and flavor, antioxidant capacity and browning of cluster wood were evaluated. The least percentage of changes in fruit weight and titratable acidity were observed at a concentration of 450 μl /l of thyme essential oil. The control treatment had the highest amount of total soluble solids in fruits (25.2 degrees Brix). Also, the results of sensory evaluation of fruit texture firmness showed that the fumigant method was better than the immersion method with gradual release of essential oil to maintain the firmness of fruit texture better. Sensory evaluation of grape fruit Smell and flavor and taste showed that at high concentrations of essential oil, the sensory evaluation index was lower. Antioxidant capacity was declining in the whole process and fumigant and immersion methods were not significantly different from each other.

The most important post harvesting factors that limiting grape berries after post harvesting are water losing and fungal decay. In this study, effect of titanium dioxide (TiO2) and soy protein isolate edible coating against postharvest decay and increasing the storage life of table grape cultivar was investigated. Uniform clusters with no disease and physical damage were packed with coated and uncoated (control) TiO2 nanoparticles. Then clusters were maintained for 31 days in cold storage at 0 ± 1 °C and RH 90 ± 5%. Grape berries abscission rate, total soluble solids (TSS), titratable acidity (TA), total phenolic content, color and clarity of grape berries, pH, antioxidant activity and total sugar characteristics were measured at intervals 6 days. The statistical analysis of results showed that the TiO2 nanoparticles treatment had significant effects in cluster and grape berries weight losing, fungal infection, TA, total phenol content and coefficient of ripening. This treatment had best flavor, quality, appearance and marketability compared with the samples without TiO2 nanoparticles treatment. In addition, the samples that treated with TiO2 nanoparticles showed higher TSS, TA, antioxidant activity, total sugar and total phenolic content. In the present study, two varieties of grapes treated with TiO2 nanoparticles in the comparison of control samples had higher quality at the end of the storage period.

Water losing and fungal decay are the main limiting factors of grape berries during storage. In this study, the effects of plastic film covered with titanium dioxide nanoparticles were investigated on the controlling of postharvest decay and increasing the shelf-life of three table grape cultivars (BidaneSefid, Gezel Ozom, and Rish Baba). The results showed that grape packed in plastic film covered with titanium dioxide nanoparticles considerably decrease berries shedding, decay incidence and weight loss. In addition to, this treatment suppresses decreasing color hue during the storage time. There was no significant difference between treated and untreated samples for berry firmness. Table grape CV. Gezel Ozom showed the best shelf life than two other cultivars. Overall, grapes packed in plastic film coated with titanium dioxide nanoparticles showed better taste, flavor, marketability and general appearance than the control because of lower decay incidence and weight loss.