Fatty acid profile, chemical composition, and sensory effects of crude glycerin on the longissimus dorsi of crossbred Boer goat kids

The objectives of this trial were to evaluate the fatty acid profile, chemical composition, and sensory effects of crude glycerin on the longissimus dorsi muscle of crossbred Boer goat kids. Twenty crossbred Boer goat kids (20.8±2.9 kg of BW at slaughter) were used in a completely randomized block design to determine the effect of partial replacement of corn by crude glycerin on chemical composition, longissimus dorsi muscle fatty acid profile, and sensory characteristics of meat. Kids were penned individually for 51 d and fed an isonitrogenous (140.0±2.0 g.kg-1 CP, DM basis) diet composed of 700 g.kg-1 concentrate and 300 g.kg-1 Tifton (Cynodon sp.) hay. Increasing levels of crude glycerin (80.0 g/100 g glycerol, DM basis) were 0, 40, 80 or 120 g.kg-1. There was no effect on the moisture, protein, or total lipids in the longissimus dorsi; however, the ash content decreased linearly with glycerin addition. Linear decrease for linoleic acid (3.57, 2.84, 3.76, and 2.33) and ω6:ω3 ratio (10.61, 9.71, 7.26, and 7.18 for CG0, CG40, CG80 and CG120, respectively) was observed with crude glycerin inclusion. Saturated, monounsaturated, and polyunsaturated fatty acids were not affected by treatments. In the sensory assessment, crude glycerin changed the toughness, color intensity, and overall appreciation of the longissimus dorsi muscle. The partial replacement of corn by crude glycerin has a low impact on chemical composition and meat fatty acid profile. Based on the overall appreciation, it is recommended to include 80 g.kg-1 crude glycerin in the diet.

本试验旨在探究粗甘油对波尔山羊杂交羔羊背最长肌的脂肪酸谱、化学成分及感官特性的影响。选取20只屠宰体重为20.8±2.9 kg的波尔山羊杂交羔羊，采用完全随机区组设计，分析以粗甘油部分替代玉米对肉品化学成分、背最长肌脂肪酸谱及感官品质的影响。试验期间羔羊单栏饲养51 d，饲喂等氮日粮（粗蛋白（crude protein, CP）为140.0±2.0 g·kg⁻¹，以干物质（dry matter, DM）计），日粮组成包含700 g·kg⁻¹精料与300 g·kg⁻¹蒂夫顿草（Cynodon sp.，狗牙根属）干草。粗甘油（甘油含量为80.0 g/100 g，以干物质计）的添加梯度设置为0、40、80、120 g·kg⁻¹。结果表明，粗甘油添加对背最长肌的水分、粗蛋白或总脂质含量无显著影响，但灰分含量随甘油添加量增加呈线性下降趋势。亚油酸含量及ω6:ω3比值随粗甘油添加量增加呈线性降低（CG0、CG40、CG80、CG120组的亚油酸数值分别为3.57、2.84、3.76、2.33，ω6:ω3比值分别为10.61、9.71、7.26、7.18）。饱和脂肪酸、单不饱和脂肪酸及多不饱和脂肪酸含量均不受试验处理的影响。感官评估结果显示，粗甘油添加会改变背最长肌的嫩度、色泽强度及整体接受度。以粗甘油部分替代玉米对肉品化学成分及脂肪酸谱的影响较小。基于整体接受度评分，推荐日粮中粗甘油的适宜添加量为80 g·kg⁻¹。