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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]

Abstract Background Improvement of biofeedstock quality for cellulosic ethanol production will be facilitated by inexpensive and rapid methods of evaluation, such as those already employed in the field of ruminant nutrition. Our objective was to evaluate whether forage quality and compositional measurements could be used to estimate ethanol yield of maize stover as measured by a simplified pretreatment and simultaneous saccharification and fermentation assay. Twelve maize varieties selected to be diverse for stover digestibility and composition were evaluated. Results Variation in ethanol yield was driven by glucan convertibility rather than by glucan content. Convertibility was highly correlated with ruminal digestibility and lignin content. There was no relationship between structural carbohydrate content (glucan and neutral detergent fiber) and ethanol yield. However, when these variables were included in multiple regression equations including convertibility or neutral detergent fiber digestibility, their partial regression coefficients were significant and positive. A regression model including both neutral detergent fiber and its ruminal digestibility explained 95% of the variation in ethanol yield. Conclusion Forage quality and composition measurements may be used to predict cellulosic ethanol yield to guide biofeedstock improvement through agronomic research and plant breeding.

Growth curves are used in a wide range of applications such as crop science and biotechnology. Besides, mathematical models for fermentation can provide more information about kinetic of cell growth, and also promote the control and optimization of cell growth during fermentation. The main objectives of this study were undertaken not only plotted the cell growth curves, determined the specific growth equations, and calculated the kinetic parameters belong to Scheffersomyces stipitis strains (ATCC 58784 and 58785) but also to modelled their cell growths by using modified logistic and modified Richards models. The results indicated that the specific growth curves of ATCC 58784 in glucose and xylose mediums were y=0.3047×Abs600-0.2656 and y=0.2322×Abs600+0.4329, respectively. For ATCC 58785, they were y=0.2639×Abs600+0.0282 and y=0.2323×Abs600+0.6211, respectively. Furthermore, for ATCC 58784, maximum growth rate and doubling time values in glucose and xylose media were 0.23, 0.11 g/L/h and 2.45, 8.58 h, respectively. For ATCC 58785, they were 0.33, 0.11 g/L/h and 2.51, 7.66 h, respectively. In addition, modified logistic and modified Richards models were tested in order to describe cell growth profiles during fermentation by S. stipitis strains. Results indicated that these models can serve as a universal equation to fit cell growth. Moreover, validation of these models demonstrated that cell growth was all predicted accurately (slope=0.96 and 0.97, R2=0.998 and 0.998 for ATCC 58784 in xylose media by modified logistic and modified Richards models, respectively; slope=1.01 and 1.01, R2=0.995 and 0.995 for ATCC 58785 in xylose media by modified logistic and modified Richards models, respectively). [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]