No abstract

Duck feet are considered as waste products because people normally do not consume duck feet. It is highly available in Malaysia and thus has the high potential to be the alternative source to produce collagen other than fish, bovine or porcine. The main objective of this study is to evaluate the physicochemical properties of different treated duck feet collagen and its effect on the quality of sardine surimi. Duck feet was stirred and soaked in 5% lactic acid solution for different time (12, 24, 36 and 48 h) at 4ºC. Another treatment for the duck feet is demineralization. Duck feet collagen was demineralized by 0.5M EDTA solution for 24 h prior soaking in lactic acid solution for 24 h. Soaking time 24, 36 and 48 h has successfully decreased fat content of duck feet collagen significantly compared to 12 h. However, no differences in yield were observed for the samples. Prolong soaking time produced duck feet collagen with higher content of imino acid (hydroxyproline + proline). The intensity of lightness (L*) for the demineralized duck feet collagen is lower compared to duck feet collagen which was not treated by EDTA. Duck feet collagen has the ability to improve the quality of sardine surimi gel by enhancing its lightness, water holding capacity, gel strength and texture with low cooking loss and expressible moisture. The folding test score of sardine surimi gel has been increased from 3.00 to 5.00 by the addition of duck feet collagen. The gel strength for sardine surimi gel with the addition of duck feet collagen is in the range of 2625.90 g.mm to 2681.58 g.mm, which is approximately 9 times higher than the gel strength of sardine surimi without collagen (280.43 g.mm).

Abstract-In the present study, the quality of Muruku, a popular Indian traditional snack prepared by deep frying, was determined. Seven different brands or types of Muruku were obtained based on packaging types. The average fat and moisture content were 29.27% to 45.47% and 0.73% to 5.35%, respectively. The ratio of polyunsaturated to saturated fatty acids falls within the healthy range of 0.20 to 0.33. The oil indices analysis showed that the values of peroxide (PV), p-anisidine (PAV), acid value (AV) and thiobarbituric acid (TBA) of the oil extracted from the Muruku were in the range of 3.52 to 10.27 meq O2/kg, 3.67 to 14.04, 3.71 to 15.73 mg KOH/g and 2.42 to 38.59 mg malonaldehyde eq/kg, respectively. Cluster analysis grouped the samples into four groups indicating differences in the quality of the snack. Discriminant analysis showed that average lightness, redness, yellowness values, saturated fatty acids content, TBA, PAV, and moisture content were the main contributors in discriminating the samples. This suggests that most of the Muruku samples were subjected secondary oxidation either due to long storage because of inappropriate packaging technology employed or exposure to light and heat, which may increase the risk of rancidity and toxicity.

The original version of this article unfortunately contained a mistake. The first author name was incorrectly submitted and published as Nik Aisyah, N.M. instead of Nik Muhammad, N. The original article has been corrected.