Table 2. Comparison of mean monounsaturated fatty acid composition expressed as mg/100 g of meat between grass-fed and grain-fed beef

Author (publication year)	Feeding system	Breed	Beef cut/muscle location	Fat content	Monounsaturated fatty acid (mg/100 g meat)
Author (publication year)	Feeding system	Breed	Beef cut/muscle location	Fat content	C14:1	C16:1	C18:1 t11	C18:1 n-9	Total MUFA
Najar-Villarreal et al. (2019)	Grass-fed	NR	Ground beef	15.7 (% crude fat)	165.4^*	671.6^*	162.5	6,073.2^*	7,436.5^*
Najar-Villarreal et al. (2019)	Grain-fed	Angus	Ground beef	19.8 (% crude fat)	177.7^*	892.3^*	195.9	7,338.1^*	8,888.8^*
Hwang and Joo (2017)	Grass-fed	Hanwoo	Sirloin	5.94 (% crude fat)	24.5^*	188.8^*	NR	2,380.5^*	2,669.9^*
	Grain-fed	Hanwoo	Sirloin	25.39 (% crude fat)	139.5^*	1,023.3^*	NR	11,772.8^*	13,282.2^*
	Grass-fed	Australian beef	Sirloin	5.15 (% crude fat)	20.3^*	167.0^*	NR	1,891.2^*	2,136.0^*
	Grain-fed	American beef	Sirloin	10.22 (% crude fat)	46.8^*	413.8^*	NR	4,133.1^*	4,712.6^*
Turner et al. (2015)	Grass-fed	NR	Ribeye	38.26 (mg/g muscle)	16.8	93.9	67.6^*	1,153.0^*	1,474.4^*
Turner et al. (2015)	Grain-fed	NR	Ribeye	84.90 (mg/g muscle)	40.4	232.5	74.7^*	2,838.5^*	3,599.9^*
Duckett et al. (2013)	Grass-fed	Angus	Ribeye, strip	2.6 (% total fat)	10.0	63.8	83.1	785.5	1,064.6
Duckett et al. (2013)	Grain-fed	Angus	Ribeye, strip	6.7 (% total fat)	41.7	226.7	9.3	2,591.2	2,859.6
Aldai et al. (2011)	Grass-fed	Asturian valley cattle	Ribeye/L. thoracis	NR	0.063 (%)^*	0.804 (%)^*	2.41 (%)	18.85 (%)	156.4
Aldai et al. (2011)	Grain-fed	Asturian valley cattle	Ribeye/L. thoracis	NR	1.171 (%)^*	1.546 (%)^*	1.841 (%)	23.17 (%)	355.9
Alfaia et al. (2009)	Grass-fed	Alentejano purebred	Sirloin/L. lumborum	9.76 (mg/g muscle)	0.9^*	10.5^*	12.1	183.2^*	220.7^*
Alfaia et al. (2009)	Grain-fed	Alentejano purebred	Sirloin/L. lumborum	13.03 (mg/g muscle)	3.1^*	26.5^*	11.0	341.8^*	417.6^*
Ponnampalam et al. (2006)	Grass-fed	Angus	Sirloin/L. lumborum	2.12 (% of muscle)	NR	NR	NR	836.0^*	930.0^*
Ponnampalam et al. (2006)	Grain-fed	Angus	Sirloin/L. lumborum	3.61 (% of muscle)	NR	NR	NR	1,582.0^*	1,729.0^*
Realini et al. (2004)	Grass-fed	Hereford	Ground beef	11.43a (% total fat)	45.0^*	246.0^*	NR	3,707.4^*	3,998.4^*
Realini et al. (2004)	Grain-fed	Angus-Hereford	Ground beef	24.57b (% total fat)	189.1^*	695.4^*	NR	9,358.0^*	10,242.5^*

Between grass-fed and grain-fed beef studies followed by asterisk indicates significant difference (at least p<0.05); NR, not reported; C14:1, myristoleic acid; C16:1, palmitoleic acid; C18:1 t11, trans vaccenic acid; C18:1 n-9, oleic acid; MUFA, monounsaturated fatty acid