Physicochemical properties of surimi gel from silver carp as affected by ultrasonically emulsified vegetable oils

Abstract

ABSTRACTThe objective of this study was to investigate the effects of ultrasonically emulsified palm oil (UE-PA), peanut oil (UE-PE), and sunflower oil (UE-SU) on the whiteness, textural, rheological, and microstructural properties of surimi gels from silver carp. Three ultrasonically emulsified oils had different specific fatty acids and oil droplet sizes of 300-400 nm. Compared with the control group, low addition of UE-SU (2.5 g/100 g) showed the highest water-holding capacity (WHC), storage modulus (G’), and hydrogen bond in surimi gels. The low addition of UE-PE (2.5 g/100 g) increased disulfide bond, β-sheet, and β-turn of surimi gel, so had higher hardness and chewiness values, comparing to those with other emulsified oils. As ultrasonically emulsified oil addition increased in surimi gels (2.5–7.5 g/100 g), hardness, chewiness, WHC, G’ were decreased, while whiteness was increased (p < .05). Light microscopy showed the most uniform distribution of oil droplets of UE-SU in surimi gels. Results demonstrated that lower addition of UE-PE and UE-SU (2.5 g/100 g) could potentially improve the whiteness, textural, rheological, and nutritional quality of surimi-based products.

Keywords

• Vegetable oils
• ultrasonic emulsification
• surimi
• texture
• whiteness
• rheology