Abstract
Purpose: To develop reduced-salt silver carp meat gels using low frequency ultrasound.
 Methods: Silver carp meat batters were prepared with 0.5, 1 (reduced-salt) and 2 % (regular salt), and sonicated (20 KHz, 500 W) for 30 and 40 min, or unsonicated (control). Changes in gel properties were evaluated in terms of color, texture, cooking loss and microstructure using color measurement, puncture test, cooking loss and scanning electron microscopic (SEM) analysis, respectively.
 Results: Ultrasound and salt exposure led to marked effects on color, texture and cooking loss in fish meat gels (p < 0.05). Reduction in salt content increased the lightness (L*) and cooking loss; and also decreased the sample values of greenness (-a*), breaking force, rupture distance and gel strength. Scanning electron microscopy (SEM) on regular-salt level samples showed that ultrasonic exposure decreased dense aggregates and increased the number and distribution of small cavity samples. Reduced-salt samples (1 % salt) subjected to 30 min sonication had better color (lighter) than control (0 min sonication), better texture (higher gel strength) and cooking loss comparable to that of regular-salt level sample subjected to 30 min sonication, and similar to microstructures from normal salt samples without ultrasound exposure.
 Conclusion: Low frequency ultrasound is suitable for preparing reduced-salt fish meat gels under suitable ultrasonic conditions.
Highlights
Silver carp (Hypophthalmichthys molitrix) is one of the major inexpensive freshwater fish species harvested commercially in China [1]
The test was done on cylindershaped slices of meat gels with TA.XT Plus texture analyzer bearing a 5-mm diameter plunger operating at a velocity of 1 mm/sec
The results showed that breaking force, distance to rupture and gel strength values of samples were affected by salt content and ultrasound treatments
Summary
Silver carp (Hypophthalmichthys molitrix) is one of the major inexpensive freshwater fish species harvested commercially in China [1]. Food products such as fermented sausages [2], surimi [3,4,5] and restructured fish [1] have been developed from silver carp. Common salt or sodium chloride is a vital additive in the processing of many foods. There is a great interest in reduced-salt products. Reduction in salt content could influence the characteristics of meat products. Reduced salt content impairs the complete solubilization or dissociation of myofibrillar proteins, thereby contributing to coarse product structure [4]. It has been shown that salt concentrations below 2 % negatively affect the mechanical and functional attributes of fish products [7]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
