الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
In the last decades consumer demands in the field of food production have changed considerably. Consumers more and more believe that foods contribute directly to their health (Mollet and Rowland, 2002). Regarding to its nutraceutical, medicinal and functional importance, several projects have promoted cactus pear for its use in multiple applications such as juice, puree, jam, …etc .
Peel is a major waste in cactus pear pulp based products accounting about 37.72% of the fruit weight. New concept of peel snacks has been defined using the détente instantanée controlée ”DIC” technique which takes place between initial and final hot air drying. The obtained results showed that DIC treatments has remarkable effect on the drying kinetics, which significantly improved and reflected in declining the drying time (T4%) by 80.20% lower than the untreated peel as drying carried out at 70°C.The micro structural modification occurred is strongly depending on the DIC processing parameters in terms of vapor steam pressure and thermal holding time. The higher steam pressure and holding time used, the higher porosity, water effective diffusivity, expansion ratio, and on the contrary the lower densities were observed. The water holding capacity as well as oil holding capacity of DIC peel snacks showed considerably higher values being (4.02 ml/g and 3.23 ml/gm) against the untreated peel (1.81ml/gm and 1.67 ml/gm, respectively). This increment is corresponding to the increment in the DIC operating parameter in terms of steam pressure and processing time as well. Results showed that the DIC operating parameters significantly affect the chemical constituents such as protein, polyphenol, antioxidant activity and ß-carotene meanwhile only the steam pressure had significant effect on fat and alcohol insoluble solids (AIS) on the contrary ash content did not depend on the operating DIC parameters. The correlation coefficients revealed critical relationships between structural and chemical characteristics. Hence, the DIC is suggested as a successful innovative technology for the production of high quality and crispy dried peel snacks.
The impact of maceration treatment for whole fruit mash and pulp with different doses of cell wall degrading enzyme pectinase and cellulase on physical and phytochemical properties was investigated. Enzyme-assisted processing for whole fruit mash and pulp significantly improved the juice yield, TSS, titratable acidity, clarity,°Brix/Acidity ratio, β-carotene, polyphenol, ascorbic acid, antioxidant activity, fructose/glucose and total sugars. On the other hand enzymatic treatment caused obviously decrease of pulp content, pH and viscosity.
Some physiochemical properties of cactus juice resultant from enzymatic treated whole fruit mash and pulp were studied after concentration step. The TSS considerably increased. In addition color changes were observed and found to be affected by concentration process whereas lightness ”L*”, redness ”a*” and yellowness ”b*” values increased with increasing the TSS content. Results showed an increasing in the ascorbic acid content and NEB, meanwhile HMF significantly decreased for the enzymatic treated whole fruit mash and pulp as compared to the untreated concentrates. Results indicate that tailoring of specific enzyme mixtures can yield antioxidant rich juice products. Optimizing a strategy for extraction of phenolic rich juice from cactus cloudy juice can offer an opportunity for its utilization in developing novel functional beverages with enhanced color appeal and high antioxidant activity.
Results revealed that the optimum treatment for enzymatic extraction of cloudy cactus juice from whole fruit mash and pulp are pectinase (200 ppm) and cellulase (100ppm) for 60 min and pectinase (100 ppm) and cellulase (50ppm) for 30 min, respectively at 40°C at the natural pH of the fruit.
In the last decades consumer demands in the field of food production have changed considerably. Consumers more and more believe that foods contribute directly to their health (Mollet and Rowland, 2002). Regarding to its nutraceutical, medicinal and functional importance, several projects have promoted cactus pear for its use in multiple applications such as juice, puree, jam, …etc .
Peel is a major waste in cactus pear pulp based products accounting about 37.72% of the fruit weight. New concept of peel snacks has been defined using the détente instantanée controlée ”DIC” technique which takes place between initial and final hot air drying. The obtained results showed that DIC treatments has remarkable effect on the drying kinetics, which significantly improved and reflected in declining the drying time (T4%) by 80.20% lower than the untreated peel as drying carried out at 70°C.The micro structural modification occurred is strongly depending on the DIC processing parameters in terms of vapor steam pressure and thermal holding time. The higher steam pressure and holding time used, the higher porosity, water effective diffusivity, expansion ratio, and on the contrary the lower densities were observed. The water holding capacity as well as oil holding capacity of DIC peel snacks showed considerably higher values being (4.02 ml/g and 3.23 ml/gm) against the untreated peel (1.81ml/gm and 1.67 ml/gm, respectively). This increment is corresponding to the increment in the DIC operating parameter in terms of steam pressure and processing time as well. Results showed that the DIC operating parameters significantly affect the chemical constituents such as protein, polyphenol, antioxidant activity and ß-carotene meanwhile only the steam pressure had significant effect on fat and alcohol insoluble solids (AIS) on the contrary ash content did not depend on the operating DIC parameters. The correlation coefficients revealed critical relationships between structural and chemical characteristics. Hence, the DIC is suggested as a successful innovative technology for the production of high quality and crispy dried peel snacks.
The impact of maceration treatment for whole fruit mash and pulp with different doses of cell wall degrading enzyme pectinase and cellulase on physical and phytochemical properties was investigated. Enzyme-assisted processing for whole fruit mash and pulp significantly improved the juice yield, TSS, titratable acidity, clarity,°Brix/Acidity ratio, β-carotene, polyphenol, ascorbic acid, antioxidant activity, fructose/glucose and total sugars. On the other hand enzymatic treatment caused obviously decrease of pulp content, pH and viscosity.
Some physiochemical properties of cactus juice resultant from enzymatic treated whole fruit mash and pulp were studied after concentration step. The TSS considerably increased. In addition color changes were observed and found to be affected by concentration process whereas lightness ”L*”, redness ”a*” and yellowness ”b*” values increased with increasing the TSS content. Results showed an increasing in the ascorbic acid content and NEB, meanwhile HMF significantly decreased for the enzymatic treated whole fruit mash and pulp as compared to the untreated concentrates. Results indicate that tailoring of specific enzyme mixtures can yield antioxidant rich juice products. Optimizing a strategy for extraction of phenolic rich juice from cactus cloudy juice can offer an opportunity for its utilization in developing novel functional beverages with enhanced color appeal and high antioxidant activity.
Results revealed that the optimum treatment for enzymatic extraction of cloudy cactus juice from whole fruit mash and pulp are pectinase (200 ppm) and cellulase (100ppm) for 60 min and pectinase (100 ppm) and cellulase (50ppm) for 30 min, respectively at 40°C at the natural pH of the fruit.
In the last decades consumer demands in the field of food production have changed considerably. Consumers more and more believe that foods contribute directly to their health (Mollet and Rowland, 2002). Regarding to its nutraceutical, medicinal and functional importance, several projects have promoted cactus pear for its use in multiple applications such as juice, puree, jam, …etc .
Peel is a major waste in cactus pear pulp based products accounting about 37.72% of the fruit weight. New concept of peel snacks has been defined using the détente instantanée controlée ”DIC” technique which takes place between initial and final hot air drying. The obtained results showed that DIC treatments has remarkable effect on the drying kinetics, which significantly improved and reflected in declining the drying time (T4%) by 80.20% lower than the untreated peel as drying carried out at 70°C.The micro structural modification occurred is strongly depending on the DIC processing parameters in terms of vapor steam pressure and thermal holding time. The higher steam pressure and holding time used, the higher porosity, water effective diffusivity, expansion ratio, and on the contrary the lower densities were observed. The water holding capacity as well as oil holding capacity of DIC peel snacks showed considerably higher values being (4.02 ml/g and 3.23 ml/gm) against the untreated peel (1.81ml/gm and 1.67 ml/gm, respectively). This increment is corresponding to the increment in the DIC operating parameter in terms of steam pressure and processing time as well. Results showed that the DIC operating parameters significantly affect the chemical constituents such as protein, polyphenol, antioxidant activity and ß-carotene meanwhile only the steam pressure had significant effect on fat and alcohol insoluble solids (AIS) on the contrary ash content did not depend on the operating DIC parameters. The correlation coefficients revealed critical relationships between structural and chemical characteristics. Hence, the DIC is suggested as a successful innovative technology for the production of high quality and crispy dried peel snacks.
The impact of maceration treatment for whole fruit mash and pulp with different doses of cell wall degrading enzyme pectinase and cellulase on physical and phytochemical properties was investigated. Enzyme-assisted processing for whole fruit mash and pulp significantly improved the juice yield, TSS, titratable acidity, clarity,°Brix/Acidity ratio, β-carotene, polyphenol, ascorbic acid, antioxidant activity, fructose/glucose and total sugars. On the other hand enzymatic treatment caused obviously decrease of pulp content, pH and viscosity.
Some physiochemical properties of cactus juice resultant from enzymatic treated whole fruit mash and pulp were studied after concentration step. The TSS considerably increased. In addition color changes were observed and found to be affected by concentration process whereas lightness ”L*”, redness ”a*” and yellowness ”b*” values increased with increasing the TSS content. Results showed an increasing in the ascorbic acid content and NEB, meanwhile HMF significantly decreased for the enzymatic treated whole fruit mash and pulp as compared to the untreated concentrates. Results indicate that tailoring of specific enzyme mixtures can yield antioxidant rich juice products. Optimizing a strategy for extraction of phenolic rich juice from cactus cloudy juice can offer an opportunity for its utilization in developing novel functional beverages with enhanced color appeal and high antioxidant activity.
Results revealed that the optimum treatment for enzymatic extraction of cloudy cactus juice from whole fruit mash and pulp are pectinase (200 ppm) and cellulase (100ppm) for 60 min and pectinase (100 ppm) and cellulase (50ppm) for 30 min, respectively at 40°C at the natural pH of the fruit.
In the last decades consumer demands in the field of food production have changed considerably. Consumers more and more believe that foods contribute directly to their health (Mollet and Rowland, 2002). Regarding to its nutraceutical, medicinal and functional importance, several projects have promoted cactus pear for its use in multiple applications such as juice, puree, jam, …etc .
Peel is a major waste in cactus pear pulp based products accounting about 37.72% of the fruit weight. New concept of peel snacks has been defined using the détente instantanée controlée ”DIC” technique which takes place between initial and final hot air drying. The obtained results showed that DIC treatments has remarkable effect on the drying kinetics, which significantly improved and reflected in declining the drying time (T4%) by 80.20% lower than the untreated peel as drying carried out at 70°C.The micro structural modification occurred is strongly depending on the DIC processing parameters in terms of vapor steam pressure and thermal holding time. The higher steam pressure and holding time used, the higher porosity, water effective diffusivity, expansion ratio, and on the contrary the lower densities were observed. The water holding capacity as well as oil holding capacity of DIC peel snacks showed considerably higher values being (4.02 ml/g and 3.23 ml/gm) against the untreated peel (1.81ml/gm and 1.67 ml/gm, respectively). This increment is corresponding to the increment in the DIC operating parameter in terms of steam pressure and processing time as well. Results showed that the DIC operating parameters significantly affect the chemical constituents such as protein, polyphenol, antioxidant activity and ß-carotene meanwhile only the steam pressure had significant effect on fat and alcohol insoluble solids (AIS) on the contrary ash content did not depend on the operating DIC parameters. The correlation coefficients revealed critical relationships between structural and chemical characteristics. Hence, the DIC is suggested as a successful innovative technology for the production of high quality and crispy dried peel snacks.
The impact of maceration treatment for whole fruit mash and pulp with different doses of cell wall degrading enzyme pectinase and cellulase on physical and phytochemical properties was investigated. Enzyme-assisted processing for whole fruit mash and pulp significantly improved the juice yield, TSS, titratable acidity, clarity,°Brix/Acidity ratio, β-carotene, polyphenol, ascorbic acid, antioxidant activity, fructose/glucose and total sugars. On the other hand enzymatic treatment caused obviously decrease of pulp content, pH and viscosity.
Some physiochemical properties of cactus juice resultant from enzymatic treated whole fruit mash and pulp were studied after concentration step. The TSS considerably increased. In addition color changes were observed and found to be affected by concentration process whereas lightness ”L*”, redness ”a*” and yellowness ”b*” values increased with increasing the TSS content. Results showed an increasing in the ascorbic acid content and NEB, meanwhile HMF significantly decreased for the enzymatic treated whole fruit mash and pulp as compared to the untreated concentrates. Results indicate that tailoring of specific enzyme mixtures can yield antioxidant rich juice products. Optimizing a strategy for extraction of phenolic rich juice from cactus cloudy juice can offer an opportunity for its utilization in developing novel functional beverages with enhanced color appeal and high antioxidant activity.
Results revealed that the optimum treatment for enzymatic extraction of cloudy cactus juice from whole fruit mash and pulp are pectinase (200 ppm) and cellulase (100ppm) for 60 min and pectinase (100 ppm) and cellulase (50ppm) for 30 min, respectively at 40°C at the natural pH of the fruit.