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Basil seed (Ocimum basilicum L.) is cultivated in large quantities in different regions of Iran. This seed has reasonable amounts of gum with good functional properties which is comparable with commercial food hydrocolloids. A central composite rotatable design was applied to evaluate the effects of temperature, pH and water ⁄ seed ratio on the yield, apparent viscosity and protein content of water-extracted Basil seed gum. All of the variables significantly (P < 0.05) affected the extraction yield, whereas the effect of water ⁄ seed ratio on apparent viscosity and the effects of pH and water ⁄ seed ratio on protein content were not significant (P > 0.05). Numerical optimisation determined the optimum extraction conditions based on the highest yield and viscosity and the lowest protein content as being temperature 68.71°C, pH 8.09 and water ⁄ seed ratio 65.98:1. Power law model well described non-Newtonian pseudoplastic behaviour of BSG. Flow behaviour index (n) and consistency index (K) of 1% crude and pure BSG samples were 0.306, 0.283 and 17.46, 20.22 Pa s n , respectively.

Two different peptones obtained by enzymatic hydrolysis of yellowfin tuna (Thunnus albacares) head waste have been shown to be effective in promoting the growth of lactic acid bacteria (Lactobacillus bulgaricus Persian Type Culture Collection (PTCC) 1332, Lactobacillus acidophilus PTCC 1643, Lactobacillus casei PTCC 1608, Lactobacillus delbrukii PTCC 1333, Lactobacillus plantarum PTCC 1058, Lactococcus lactis PTCC 1336, and Lactobacillus sakei PTCC 1712). Peptones obtained from the enzymatic hydrolysis with Alcalase or Protamex were used instead of the standard peptones used in commercial MRS media. Peptones produced by Alcalase and Protamex had a 34% and 19% degree of hydrolysis, respectively. The resultsshowed that the peptones from Alcalase and Protamex were better at promoting lactic acid bacteria (LAB) growth than the commercial MRS media (P<0.05). The choice of proteolytic enzyme used to produce the fish hydrolysate had a considerable impact on the performance of the resulting hydrolysate, both in terms of maximum growth rate and biomass production. Peptones produced using Alcalase, with a higher degree of hydrolysis, induced better growth and performed better overall as an LAB substrate than those using Protamex. Current study revealed that enzymatic-modified fish by-products can be used as low cast nitrogen source for bacterial growth.

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Fish protein hydrolysate was produced from the viscera of yellowfin tuna (Thunnus albacares). Hydrolysis conditions (enzyme activity, temperature, and time) were optimized using response surface methodology. A factorial design was applied to minimize enzyme utilization and modeling of degree of hydrolysis (r 2 =0.94). Lack-of-fit test revealed a non-significant value for the model, indicating that the regression equation was adequate for predicting the degree of hydrolysis under any combination of the variables (P<0.05). The optimum conditions to reach the highest degree of hydrolysis were: 60.4°C, 90.25 min, and a protease (Alcalase 2.4 L) activity of 70.22 AU/kg protein.The spray-dried tuna visceral protein hydrolysates had relatively high protein (72.34%) and low lipid (1.43%) content. The chemical score of the hydrolysate indicated that it fulfils adult human nutritional requirements except for methionine. Lysine and methionine were the first and the second limiting amino acids in that order. Phenylalanine was the predominant amino acid in the hydrolysates with respect to common carp requirement. In addition, the protein efficiency ratio of tuna visceral hydrolysate was 2.85-5.35.

Chemical (pH 3.3, 70°C, 85°C; pH 12, 70°C, 85°C) and biochemical (Alcalase, Protamex, Neutrase, Flavourzyme, and Trypsin) hydrolysis of Persian sturgeon (Acipenser persicus) visceral protein was investigated. The results of this study revealed that there are significant differences between enzymes in terms of degree of hydrolysis (DH%; P < 0.05). Alcalase-hydrolyzed fish protein had the highest DH% (50.13%), and Trypsinhydrolyzed fish protein had the minimum DH% (14.21%). The highest DH% in chemical hydrolysis was related to pH 3.3 at 85°C (68.87%). The highest protein recovery (83.64%) and protein content (73.34) were related to enzymatic hydrolysis by Alcalase. The results of current study showed the significant effect of hydrolysis conditions on fish protein hydrolysate properties. Microbial enzymes could produce fish hydrolysates with higher degree of hydrolysis when compared to animal enzyme. Also, in chemical hydrolysis it is clear that hydrolysis at the lower pH and at higher temperature causes to more protein recovery and degree of hydrolysis.

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In this research enzymatic hydrolysis of rice bran protein concentrate (RBPC) and soybean Protein (SBP) as control were studied with 3 commercial enzymes (Alcalase®, Papain and acommercial 3-enzyme cocktail containing of 1.6 mg ml − 1 Trypsin, 3.1 mg mlChymotrypsin, 1.3 mg ml −1 Aminopeptidase (SIGMA P7500) and 7.95 mg ml −1 pronase type XIV (SIGMA P5147) by the pH stat method. The hydrolysis was carried out at temperature of 28 C, 60 min and pH 8.00. Results were showed that RBPC, and SBP had higher Degree h y d r o l y s i s ( D H % ) w i t h A l c a l a s e ® e n z y m e . Alcalase®had stronger capability for hydrolysis compared to the other tested enzymes. After 60 minute of hydrolysis time, the DH% of Alcalase® for RBPC and SBP was 12.69 and 12.50 %, respectively. In contrast, papain enzyme was showed lowest DH% in three substrates that 1.56 and 1.24 % were for SBP and RBPC, respectively.The hydrolysis of the protein fraction performed the three enzymes on the two substrates was followed in SDS-PAGE. RBPC and SBP showed almost complete digestion with Alcalase® enzyme after 60 minutes. 3-enzyme cocktail enzyme hydrolyzed better the RBPC than the SBP. Papain enzyme had less effect on the two substrates than other 2 enzymes. It was found that Alcalase® has highest capability for hydrolysis compared to other enzyme preparations. The high value protein hydrolysates prepared by Alcalase® can be used as value added ingredients in many food formulations. They are also suitable for a broad range of industrial food applications and also for cosmetic and personal care products.