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In this study three technological attempts were applied to produce low sodium smoked herring fish with high quality. The first technological attempt was reducing time of salting from 48 to 24 h. The second attempt was using wet salting method with different concentration of brine solution (8, 15 and 26% NaCl) instead of dry salting method. The third attempt was replacement of sodium chloride with some salt replacers such as KCl, K-Lactate and mixture of them at different levels 20, 40 and 60%. Immediately after processing all treatments were packed in polyethylene bags under vacuum and then stored at 4ºC for 3 months. Treatments were evaluated chemically (Moisture content, salt, Na, K, pH value, TVBA, TMNA, TBA and PV), physically (WHC and plasticity), microbiologically (Total bacterial count, Psychrophilic, Halophilic, coliform, Staphylococcus aureus, Salmonella spp, Clostridium botulinum and yeast and mold counts) and organoleptically. Results suggested that salt replacers (KCl, K-Lactate and mixture of them) should be used until a level of 40 % and brine solution should be used at 15% NaCl and dry salting method for 24 h instead of 48 h to obtain low sodium smoked herring fish with high eating quality.

Colloids are of vital role for improving the quality of foods including that of psyllium, locust bean and pectin which is found in orange peel albedo. These colloids are also of value for clinical nutrition. The last opinion could be confirmed by the chemical analysis which revealed that locust bean seeds had higher total phenolic compounds (485.28 mg/100 g) while psyllium seeds (297.54 mg/100 g) and orange peel albedo (246.11 mg/100 g) showed nearly the same level. Major phenolic compound was pyrogallol for locust bean, being cholchecein for other two colloids sources. Total flavonoid compounds were higher for psyllium seeds (536.46 mg/100 g) and locust bean seed (275.76 mg/100 g), being less for orange peel albedo (113.65 mg/100 g); major flavonoid in all sources was the hesperidin. The best eating qualities recoded for psyllium sausage followed by locust bean sausage. Generally, all three colloids sources improved the eating quality of beef sausage. Plasticity confirmed the results of sensory evaluation where the best sample was that of psyllium sausage. Higher pH value after 6 months storage at-18ºC was in line with the best Water Holding Capacity (WHC) and plasticity levels recorded for psyllium sausage. Color intensity and TBA value were best for locust been followed by psyllium treatments. The lowest color intensity was in line with the highest TBA value. The keeping quality was better when adding the tested colloids; TVN, TBA value, Total Bacterial Count (TBC), Yeast and Mold (Y and M) count was lowest for psyllium followed by locust bean treatment. Other colloids showed the same trend but at lower degree.

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Strawberry is a non-climacteric fruit but exhibits very limited postharvest life due to its rapid softening and decay. Therefore, the current study was carried out to evaluate the effect of edible coatings using chitosan (CH) and chitosan nanoparticles (CHNPs) to improve the quality and extending the shelf life of strawberries during storage. Chitosan nanoparticles (CHNPs) were prepared by an ionic gelation method. The size and shape of the synthesized CHNPs were observed by transmission electron microscopy (TEM) technique. The strawberry samples were stored (after coating) at ambient temperature (25±3°C) and cold temperature (6±2°C) then, we evaluated the effectiveness of edible coating for physicochemical and microbiological properties, as well as the shelf-life during storage. The results of the TEM showed that the average particle size was 18.8-21.8 nm. At the different temperatures of storage, the samples coated with CHNPs had lower values of weight loss, decay, total soluble solids, and malondialdehyde concentrations. The same treatment had higher levels of total acidity and anthocyanin compared to the CH and uncoated treatments, that lead to preserving their quality properties and extending the shelf-life. Also, counts of total aerobic, mold, and yeast for strawberry samples treated by CHNPs were lower than those for CH and control treatment during the storage. In conclusion, the antimicrobial edible coating by CHNPs improved the qualitative characteristics and increased the shelf-life from 2 to 6 days for fruits stored at 25±3°C and from 8 to 16 days for samples stored at 6±2°C.