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In this study, apricot samples were dried by using different drying methods (tray drying, microwave drying, and freeze drying). Moreover, different pretreatments (infrared, ultrasound, and treatment with dipping green tea extract) were also applied to the samples. The effect of process conditions on physical and chemical quality of dried apricot samples were investigated. It was aimed to come of age of these technologies as an alternative to conventional pretreatments. Among all drying techniques, the shortest processing time was achieved by microwave drying at 270 W. Midilli was found to be the best model that fits the moisture ratio values among 10 thin layer models. Freeze dried samples had the lowest water activity which ranged from 0.2260 to 0.4868 and rehydration capacity of dried samples were found to be between 2.40 and 3.09. Besides, it was found that the total phenolic content of dried apricots varied between 99.24 and 512.60 mg GAE/100 g dry matter. In addition, the maximum antioxidant activity values for microwave drying (270 W) were obtained in the green tea extract pretreated samples and calculated to be 1.85 ± 0.01 mg TE/g dry matter. NMR and SEM analysis were also applied to the samples. To sum up, it can be declared that microwave technology and green tea extract pretreatments were superior and had beneficial impacts on the end product's quality. [ABSTRACT FROM AUTHOR]

The aim of the study is to enrich pasta with cornelian cherry powder, a product with high bioactive contents. In this way, it was aimed to obtain a new product that is more nutritionally advanced and can contribute to the country's economy. In this study, cornelian cherry with high bioactive content and an attractive color advantage was used for the enrichment of the pasta formulation. In addition, the pasta production procedure was revised by applying microwave technology for drying. Cornelian cherry powder:dough ratio, dough thickness, and microwave power were optimized with response surface methodology. Total phenolic content, antioxidant activity, color, and water‐holding capacity were determined as responses. Optimum conditions were found as 4.53% for powder:dough ratio, 0.1 cm for dough thickness, and 270 W for microwave power. According to optimization results, it was detected that the cornelian cherry powder:dough ratio affected the total phenolic content and antioxidant activity, and microwave power was found to be effective only on antioxidant activity. For optimum conditions, the total phenolic content and antioxidant activity were found as 1.29 GAE/g and 0.5 mg TE/g, respectively. The characterization analysis showed that the microwave–dried sample shrank less than those dried with the conventional method. In Fourier transform infrared spectroscopy (FTIR) results, it was determined that the amount of carbohydrates in the samples obtained under optimum conditions was lower than that of control. It has been observed that the application of microwave technology for drying pasta enriched with cornelian cherry powder had positive effects on the quality of the final product. [ABSTRACT FROM AUTHOR]

Currently, the majority of fresh apricots destined for the production of dried apricots undergo sulphur oxide fumigation before drying to protect the fruit against fungal spoilage. To eliminate the use of sulphite, packaging assisted with essential oil is a promising strategy to increase shelf-life of dried apricots since it does not impact its flavor characteristics. In this study, three essential oils were selected: clove, lemongrass and thyme. They were screened for antifungal activity against Eurotium spp. with different methods: micro- and macro-dilution and agar-diffusion. Growth/no-growth data were used to develop models for all three methods. Clove exerted the strongest antifungal activity with an inhibitory concentration of 0.075%, 0.035% and 0.05% through respectively micro-dilution, macro-dilution and agar diffusion. For thyme the following values were obtained: 0.775%, 0.070% and 0.100%. This means that the antifungal activity of thyme is 10 times lower in micro-dilution and 2 times lower in macro-dilution and agar diffusion compared to clove. Through micro-dilution, lemongrass was found to have the second highest antifungal activity (0.25%). When used in the volatile atmosphere of dried apricots and in macro-dilution, the antifungal activity of lemongrass was the lowest, with respective values of > 0.200% and 0.105% for G/NG prediction. [ABSTRACT FROM AUTHOR]

In this study, wheat straw was pretreated with a microfluidizer to improve its enzymatic hydrolysis and ethanol yields. The pretreatment was performed at various pressures (500, 1000, and 1500 bar) and solid loadings (1, 2, and 3%). The microfluidized biomass was then subjected to hydrolysis and simultaneous saccharification and co-fermentation (SSCF) experiments at different enzyme loadings (5, 10, and 15 FPU/g dry wheat straw) using a mutant yeast. The results indicated that the microfluidization method alters the structure of biomass and leads to a reduction in lignin content. The samples pretreated at 1% solid loading contained the minimum lignin concentration and provided the maximum sugar and ethanol yields. These results signified that the microfluidization method is more effective on biomass at low solid loadings. The process conditions were optimized for higher ethanol and sugar yields using response surface methodology (RSM). The optimum pressure and solid and enzyme loadings were found as 1500 bar, 1%, and 15 FPU/g dry wheat straw, respectively. The yields obtained at this condition were 82%, 94%, and 65% for glucose, xylose, and ethanol, respectively. High sugar yields implied that microfluidization is an effective pretreatment method for cellulosic ethanol production. On the other hand, low ethanol yield may indicate that the microorganism was sensitive to inhibitory compounds present in the fermentation medium. [ABSTRACT FROM AUTHOR]

Microwave-assisted extraction (MAE) is commonly used in recent years as an innovative approach to enhancing the quality of extracts while decreasing the extraction time and the solvent consumption in comparison to conventional techniques. In this study, the influence of microwave power, solid concentration and extraction time on total phenolic content (TPC), colour values and dielectric properties of Caucasian whortleberry were investigated. The process variables were optimized using response surface methodology. The highest TPC from Caucasian whortleberry was obtained at an extraction time of 3.5 min, a solid concentration of 15% and a microwave power of 360 W. The results showed that L* and a* values of the extracts were highly correlated with TPC by a second-order polynomial. Moreover, no significant difference was found in dielectric properties between the groups. [ABSTRACT FROM AUTHOR]