Effects of herbal plants supplementation on tenderness and water holding capacity of chevon

An experiment was conducted to investigate the effects of dietary herbal plants supplementation as antioxidants on tenderness and water holding capacity of male meat. Thirty two male goats were used in a completely randomized design to determine the effects different dietary supplementation of antioxidants (control, vitamin E, Andrographis paniculata (AP) and turmeric) on kids. The diet fed was a total mixed ration fed for 100 days with iso-caloric (2.4 M Cal/kg DM) and iso-nitrogenous (15 percent). The animals were slaughtered at end of experiment and three muscles including Longissimous dorsi (LD) were taken. The muscles were vacuum-packed and displayed for 0, 7 and 14 days in a chiller at 3-4°C. Water holding capacity measurements of the LD muscle included drip loss and cooking loss. At 0, 7 and 14 days of refrigerated retail display storage, the LD sample was weighed and put on a plastic hurdle. After a 24 h storage period at 4°C, the meat samples were removed from the bag and reweighed, accounted for the percent drip loss (Lanza et al., 2003). The measurement of cooking loss was conducted on each LD sample at 3 display periods (days 0, 7 and 14). About 30 g of each sample was weighed, held in plastic bags and immersed in an 80C water-bath until the internal temperature reached 78C. Then , the bags were cooled under running tap water for 30 min, blotted dry with paper towels, and reweighed. The percentage of cooking loss was calculated from the difference between the weights (Lanza et al., 2003). At the end of each display storage time (0, 7 and 14 days) the cuts of LD muscle were frozen and stored at -80°C. Prior to the mechanical assessment of tenderness, the cuts were thawed at 4°C, placed on aluminum pans, and covered with aluminum foil. The cuts were then cooked in water-bath to an internal temperature of 78'C and maintained at this temperature for an additional 10 min. After cooking, cuts were chilled overnight at 4'C before core removal (Kannan et al., 2002). To standardize the instrument was set with a 30-kg load cell and a crosshead speed of 3s/min (Sazili et at., 2005). Up to 3 cores (0.9cm diameter) were removed as close to the longitudinal orientation of the muscle fibers as possible. Each core was placed on the base plate of a TA-HO plus texture analyzer (Stable Micro Systems, UK) fitted with a Warner-Bratzler blade and sheared once in the centre and perpendicular to the longitudinal direction of the fibers. In the present experiment the least square means for the percent of drip loss and cooking loss, as well as the effect of the time of display on the cooking loss in the LD muscle were not affected (P 0.05) by the treatments. However, the drip loss increased (P > 0.05) from 1.77% to 3.90% by day 7 of the display and remained unaffected (P > 0.05) thereafter. Tenderness may be the most important eating quality parameter that determines consumer acceptability (Miller el aI.,2001; Kannan, et al., 2002). Tenderness values for goat meat are often in the acceptable range for consumer (Webb et al., 2005). In the present experiment the Warner-Bratzler shear force was not affected (P >0.05) by the dietary supplementation of antioxidants in LD muscle, but the display time significantly improved (P < 0.05) tenderness at 14 days.