Effect of salt, sugar and monosodium glutamate on the viscoelastic properties of fish cracker ("keropok") gel

Rheological and microscopic studies were carried out on the fish cracker ('keropok') gels. A hard gel is very important for the production of uniform, round, and thin slices of dried 'keropok' and easier for mechanical slicing. The addition of 2% salt in the 'keropok' gel increased the storage modulus (G′), and reduced loss tangent (tan δ = G″/G′). An increase in the fish content in 'keropok' also increased the G′ and reduced tan δ. Gels having higher values of storage modulus G′ and lower tan δ values, indicative of a strong elastic network, showed well crosslinked fish muscle bundles in the microscopy studies. In the absence of salt, the fish protein appeared to be in lumps and this has resulted in low storage modulus G′ and higher tan δ values. Lower the temperature of the gel to 5C will result in 5-6 fold increase in the G′ value

Effect of salt, sugar and monosodium glutamate on the viscoelastic properties of fish cracker ("keropok") gel

Rheological and microscopic studies were carried out on the fish cracker ('keropok') gels. A hard gel is very important for the production of uniform, round, and thin slices of dried 'keropok' and easier for mechanical slicing. The addition of 2% salt in the 'keropok' gel increased the storage modulus (G′), and reduced loss tangent (tan δ = G″/G′). An increase in the fish content in 'keropok' also increased the G′ and reduced tan δ. Gels having higher values of storage modulus G′ and lower tan δ values, indicative of a strong elastic network, showed well crosslinked fish muscle bundles in the microscopy studies. In the absence of salt, the fish protein appeared to be in lumps and this has resulted in low storage modulus G′ and higher tan δ values. Lower the temperature of the gel to 5C will result in 5-6 fold increase in the G′ value

Effects of different types and concentration of salts on the rheological and thermal properties of sin croaker and shortfin scad skin gelatin

The aims of this study were to examine the effect of salts (CaCl2, CaSO4 and MgSO4) on the rheological and thermal properties of gelatin extracted from the skins of tropical fishes, sin croaker (Johnius dussumeiri) and shortfin scad (Decapterus macrosoma). It was found that the melting temperatures of fish skin gelatins were increased by 1.5 times as compared to bovine gelatin which was only increased by 0.5 times after holding for 2 h at 5°C. The storage (G') and loss (G") modulus of fish skin gelatins were improved with the addition of calcium sulphate (CaSO4) and magnesium sulphate (MgSO4), respectively. However, the storage (G') and loss (G") modulus of gelatin solutions were decreased with the addition of calcium chloride (CaCl2). Magnesium sulphate (MgSO4) was found to be an effective salt to improve the bloom value, elastic and viscous moduli of the fish skin gelatin. This study showed that shortfin scad skin gelatin with salt addition possessed better thermal and rheological properties than sin croaker gelatin ©All Rights Reserved

Effects of different types and concentration of salts on the rheological and thermal properties of sin croaker and shortfin scad skin gelatin

The aims of this study were to examine the effect of salts (CaCl2, CaSO4 and MgSO4) on the rheological and thermal properties of gelatin extracted from the skins of tropical fishes, sin croaker (Johnius dussumeiri) and shortfin scad (Decapterus macrosoma). It was found that the melting temperatures of fish skin gelatins were increased by 1.5 times as compared to bovine gelatin which was only increased by 0.5 times after holding for 2 h at 5°C. The storage (G') and loss (G") modulus of fish skin gelatins were improved with the addition of calcium sulphate (CaSO4) and magnesium sulphate (MgSO4), respectively. However, the storage (G') and loss (G") modulus of gelatin solutions were decreased with the addition of calcium chloride (CaCl2). Magnesium sulphate (MgSO4) was found to be an effective salt to improve the bloom value, elastic and viscous moduli of the fish skin gelatin. This study showed that shortfin scad skin gelatin with salt addition possessed better thermal and rheological properties than sin croaker gelatin ©All Rights Reserved

Effect of fish, starch and salt contents on the microstructure and expansion of fish crackers ('keropok')

Light microscopy studies on the fish cracker gel and expanded product ('keropok') emphasised the role of fish proteins in the starch expansion process. The addition of salt (20 g kg-1) in the 'keropok' helped to distribute evenly the starch in the fish protein. Formation of thin fish muscle bundles assisted the expansion of 'keropok'. At 700-900 g kg-1 fish content, the fish muscle bundles formed a continuous network that caused a drop in the 'keropok' expansion. From the scanning electron microscopy study, ridges were found in samples (containing 600-900 g kg-1 fish content) with 20 g kg-1 salt at high magnification