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The pectinase enzymes are involved in several industrial applications, and industrial waste is one of the largest environmental pollutants, so this study aims to Endo-polygalacturonase (endo-PG) producing using Aspergillus niger AUMC 4156, Penicillium oxalicum AUMC 4153 and P. variotii AUMC 4149 by using some agro-industrial wastes (dried orange peel and sugar beet pulp) as a sole raw carbon source for degradation these waste in the process of urban wastes disposal. The fermentation process was carried out as a submerged culture technique under both shaken and static culture conditions. A. niger AUMC 4156 was the most promising producer of endo-PG under static conditions while P. oxalicum AUMC 4153 was the highest producer of endo-PG under shaken conditions. Sugar beet pulp proved to be the most preferable to orange peel as the only source of carbon in both shaken and static cultures. The medium that encompassing orange peel as a single carbon source afforded the highest protein content with all tested fungal strains in stirred and static cultures in comparison with sugar beet pulp. The highest activity of endo-polygalacuronase that produced using A. niger AUMC 4156 and P. oxalicum AUMC 4153 was achieved by using sugar beet pulp at 3% concentration under static cultures, meanwhile maximal enzyme activity produced by both fungal strains required 2% sugar beet pulp under shaken cultures. Sugar beet pulp showed promised potential as a good inducer for endo-polygalacturoase production, and enzymes production depended on fungal strains, culture medium, and submerged fermentation conditions.

The present study evaluated the microbiological, chemical, and organoleptic aspects of irradiated fresh fish and its products to extend their shelf life. Fresh fish and its products were irradiated at three doses (1.5, 3.0, and 4.5 kGy) used for preservation to study the effects of irradiation on their microbiological properties, fatty acid composition, and organoleptic properties. Irradiated fresh bolti fish, smoked herring, and smoked mackerel were evaluated microbiologically, chemically, and organoleptically. Radiation treatment not only reduced the counts of aerobic bacteria, fecal streptococci, molds, and yeasts but also destroyed all the Staphylococcus aureus cells, improving the hygienic quality of the fresh and smoked fish samples. Irradiation increased the peroxide, acid, and thiobarbituric acid values, but they remained within acceptable levels. No new fatty acids or other artifacts due to irradiation were observed. Irradiation of 4.5 kGy greatly reduced the organoleptic quality scores of fresh bolti fish, indicating that the optimum radiation dose for this fish was 3.0 kGy. Smoked herring and mackerel could be irradiated with up to 4.5 kGy without adverse effects on their organoleptic properties.

The aim was to develop nutritious drinks using date nectar with the two most popular Saudi date cultivars (Khalas and Sukkari) and spirulina at different substitution rates. The date puree was prepared with different concentrations of pectin enzymes. The approximate composition, microbiological quality, sugars, vitamins, and minerals of date puree and spirulina, as well as the contaminants, physical properties, fatty acids, and phytopigments of spirulina were evaluated. Chemical composition and sensory properties of the developed date drinks were also assessed. The results showed that spirulina is safe, free from contaminants and heavy metals, and appeared to contain appreciable amounts of essential fatty acids, amino acids, vitamins, minerals, and phytopigments. The microbiological loads of date puree and spirulina were very low, and there were no pathogenic microbes were found. Spirulina contained higher amounts of total solids, ash, protein, minerals, fiber, fat, and vitamins, than date puree, indicating its suitability as a rich source of nutrients for food fortification. In both date types, treatment of puree with 400 ppm enzyme yielded nectar with higher scores in all sensory attributes, indicating that this is a suitable concentration to yield acceptable juice amounts. The substitution of date nectar with 10% spirulina gave the highest scores for sensory attributes; consequently, this concentration was used for the formulation of functional nectar from date nectar and spirulina. Incorporation of 10% spirulina in date nectars showed a significant increase in the contents of total solids, protein, essential amino acids, ash, fat, sugars, carotenoids, and chlorophyll in the date nectars, thereby improving its nutritional and health properties.

Fish quality is important in the food industry. Studies on the nutritional, microbial and minerals in Indian mackerel fish are limited. Therefore, this study was carried out to assess the quality and production of fish products (balls and fingers). Additionally, the effect of frozen storage for six months on the microbial, nutritional and sensory evaluation of fish balls and fingers was studied. The obtained results showed that the estimated minerals (zinc, cadmium, chromium, copper, lead and mercury) contents in Indian mackerel muscles were lower than the maximum permissible limits for human consumption. The levels of total bacterial counts and total yeast counts in Indian mackerel purchased from three different stores varied. After 6 months of storage, the microbial content decreased in Indian mackerel fish balls and fingers to less than 2.0×102 CFU/g, which was due to the effect of freezing on the growth and activity of microorganisms, while the carbohydrate, fat and energy contents increased, and the ash, protein and moisture contents decreased; however, Indian mackerel fish fingers had elevated ash, carbohydrate, fat, protein and energy contents and a reduced moisture content after freezing. Sensory evaluation of Indian mackerel balls and fingers at the start and end of the storage period (6 months) revealed good scores for appearance, odor, texture, taste and acceptability. These results provide insights into the benefits of good-quality Indian mackerel fish in the fish product industry and their availability after storage for six months.

In Saudi Arabia, walnuts are most edible snacks that possess different pharmacological effects. However, their effects on diabetic patients need to be examined. Thus, this study investigated the gross chemical composition, specific minerals, fatty acids and phenolic compounds of walnut seeds in addition to clarify the effect of the consumption of walnuts in different ratios (2.5, 5 and 7.5%) on streptozotocin-induced diabetes in rats. The chemical analyses revealed that the walnut seeds are rich in fat, protein and carbohydrates in addition to potassium, magnesium, calcium and phenolic compounds. Walnut seed oil had a high content of polyunsaturated fatty acids followed by monounsaturated fatty acids and saturated fatty acids thereafter. Biological results revealed that consumption of walnuts as 2.5, 5 and 7.5% of a basal diet fed to diabetic rats had a significant effect in elevating body weight gain and the feed efficiency ratio, significantly decreased the glycosylated haemoglobin (HbA1c) and glucose levels, and significantly increased circulating insulin compared to the positive controls. At the same time, consumption of 7.5% walnut seed powder in the basal diet restored the haemoglobin level and HbA1c values and also improved the antioxidant biomarker to within the values of the negative control group. Regarding the chemical constituents, walnut seeds are rich in fatty acids and phenolic compounds that give positive effects for consumption and also have ameliorative effect on streptozotocin-induced diabetes in rats.

A relatively short storage life is considered a major problem for the transportation of strawberries across long distances to markets and for exportation. The aim of this research is to study the combined effects of potassium sorbate and radiation (3 kGy) on the microbial load, shelf life and most of the biochemical constituents such as vitamin C and total soluble solids of strawberries. A potassium sorbate (1%) treatment was combined, in practical application, with irradiation (3 kGy) to extend the shelf life of strawberries. All strawberry samples were stored at 4 ± 1 °C (90–92% RH). Quality assessment of the microbial and biochemical constituents, vitamin C, and TSS during the storage period was performed. The results showed that Gamma irradiation alone at 3 kGy extended the shelf life of strawberries to 21 days. Further extension of the shelf life to 21 days was obtained when irradiation (3 kGy) was combined with potassium sorbate treatment. All treatments caused non-significant decreases in vitamin C content during storage, except for the treatment of strawberries with a solution of potassium sorbate, which caused a significant decrease in the vitamin C content, and a gradual decrease in the vitamin C content occurred with an increase in storage time for all treatments.

This research investigated the chemical analysis and sensory evaluation of low-calorie formulated pumpkin jams after storage for six months and the effects of the consumption of low-calorie jams on diabetic rats. Pumpkin jam with sucrose, fructose, stevia, and aspartame sweeteners and soybean was prepared and stored at 10°C for six months. Rats were divided into group 1 (negative control), group 2 (positive diabetic groups), and groups 3, 4, and 5 (diabetic groups treated with 10% sucrose, fructose, and stevia soybean jam, respectively). The results indicated that the contents of protein, fat, ash, and fibre were increased in the low-calorie formulated pumpkin jams. The highest sensory scores were recorded for sucrose and fructose soybean jams and then for stevia soybean jam, while the aspartame soybean jam showed significantly lower scores after storage for 3 and 6 months. Rat groups 4 and 5 showed significant decreases in the glucose level, and liver function enzymes activity showed significant increases in insulin and glycogen levels compared to group 2. Conclusion. Low-calorie pumpkin jams with soybean can be stored for 3 months at 10°C without any change. Stevia pumpkin jam with soybean has antidiabetic effects.

A study was conducted to assess the effect of radiation on Microbiological quality , chemical composition and organoleptic qualities of fresh Zingiberofficinalerhizomes or ginger. Fresh ZingiberofficinaleRhizomes were treated by using three doses of gamma radiation, 5.0, 10.0, 15.0 KGy. The results showed that radioactive transactions have led to a significant reduction in total number of bacteria; yeast and fungi. The results also revealed that Fresh Zingiberofficinalerhizomes weresensitive to irradiation. At high doses of 10.0 KGy, moderate changes were detected at chemical composition. However, a significant difference in the texture with the dose of 15.0 KGy was observed compared with control.