Effect of electric stimulation on histological traits and color of carcasses in old duck and chicken

Abstract

The effect of electric stimulation on some quantitative character of old duck and chicken carcasses were the main aim of the present study. The device for measuring meat tenderness was designed at department of Food Sciences, College of Agriculture, and University of Basrah. A total of 36 old duck and same number of spent layer chickens aged78.21 week’s birds were slaughtered with knife manually. They de-feathered, and all internal organs were removed. Carcasses were divided into three groups, the control group (no electric stimulation), the second treatment group (electric conductivity 3.67 V/cm) with low voltage [110 volt]) and 1% saline solution, the third treatment group (7.33 V/cm) with 220 V voltage and 1% saline solution. Traits were measured at 25 min, 6 hrs and 24 hrs after electric stimulation. The carcasses were stored for 30 and 60 days. The following histological parameters were determined; sarcomere length, muscle fiber length, muscle fibres breaking index and color. The results indicated that length of sarcomere and muscle fibre breaking index were significantly(P≤0.05) affected by electric stimulation, because there was an increase in sarcomere length and muscle fiber breaking index of third treatment in chicken with an increasing interval of time. There was a significant (P≤0.05) decrease in muscle fiber diameter in electric stimulation treatment three (duck and chicken) with the time progress. Duck differed significantly when compared to chicken. Statistical analysis showed a significant effect of electric stimulation on color lightness (L). Duck appeared to be darker in color than chicken. Treatment group three revealed blue coloration at 25min, 60 days in both duck and chicken. Whereas other treatment groups showed yellowness (b) color. Similarly, stimulation affected color redness (a) where all groups showed greenish except 30 and 60 day intervals, their color was reddish and value of (a) of duck was less than of chicken. Electric stimulation (especially 220 V voltage) improve meat tenderness of both chicken and duck.