الفهرس 
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Abstract
Fermented fish is a biotechnological process based on hydrolysis of fish components through specific microorganisms or enzyme activities. This investigation aimed to exploit roe-free mullet fish to produce microbial fermented mullet products by inoculation with Lactobacillus plantarum bacteria (L), Saccharomyces cerevisiae yeast (S), or mix (M) of them compared to natural (T) one. Compared to T products; L, S, and M products revealed high levels of moisture, protein, and fat that ranged from 63.50- 66.76%, 63.18- 64.17%, and 20.80- 22.94%, respectively. The essential to the non-essential ratio of amino acids in L, S, and M products were 0.96 to 1.06. Umami taste, calculated protein efficiency ratio (1.94-2.22), and calculated biological values (84.02- 86.55) of L, S, and M products were higher. While caloric values (149.67- 166.88 kcal/100g) were close to the T product (157.19 kcal/100g). Thiobarbituric acid reactive substances were (<1. mg malonaldehyde/kg), total volatile basic nitrogen (77.11- 118.65 mg/100g sample), and salt (3.56-3.75%) contents in L, S, and M products were significantly less than T product. The highest reduction (16.36%) in moisture content was observed after 5 days of salting with 15% salt to T treatment. Aerobic and anaerobic counts in L, S, and M products were higher as ranged between 8.08-8.38 log CFU/g and 3.78-4.36 log CFU/g, respectively. Bacterial. analysis did not show the presence of Salmonella, Shigella, E. coli, and Clostridium botulinum except Staphylococcus spp and Proteus spp in all products. The highest total biogenic amines (BAs) including spermine, cadaverine, histamine, and tyramine were 48.49, and 37.49 mg/kg in L and S treatments, respectively. All natural and microbial fermented mullet fish products (L, S, M, C, and T) were below the maximum permissible limit of total BAs (750–900 mg/kg). Stored fermented mullets at -18°C for 6 months had a declining pattern in aerobic and Staphylococcus count in all treatments. Microbial fermentation products (L, S, and M) revealed the highest sensory properties, which ranged from extremely like to very like. In conclusion, microbial fermentation is an effective method for producing high-quality fermented fish products from roe-free mullet fish.