Dynamics of free amino acids in beef during thermal processing and mathematical modeling of doneness correlation

Jiayu Sun; Lifen Wang; Zehua Huang; Nianguo Guo; Hongzhou An; Xiaobin Zhan; Mehdi Abddollahi; Zoltan Kovacs; Jiayu Sun; Lifen Wang; Zehua Huang; Nianguo Guo; Hongzhou An; Xiaobin Zhan; Mehdi Abddollahi; Zoltan Kovacs

doi:10.48130/fmr-0024-0027

Figures (3) Tables (6)

Figure 1.
SDS-PAGE map of beef with different doneness, Lv1−Lv5 represents the center temperature of beef at 50, 58, 66, 73, and 80 °C, respectively.
Figure 2.
(a)−(f) Logistic curve of different amino acids with beef central temperature. (g)−(l) Logistic curve of different amino acids with beef central temperature after enzymatic hydrolysis. Basic amino acids (BAA), acidic amino acids (AAA), hydrophobic amino acids (HAA), sulfur amino acids (SAA), aromatic amino acids (ARAA), total amino acids (TAA).
Figure 3.
Scatter diagram of each sample after projection. 0 represents raw beef; 1−5 represents the center temperature of beef at 50, 58, 66, 73, and 80 °C, respectively.

Compounds	Raw beef (mg/g)	Lv1 (mg/g)	Lv2 (mg/g)	Lv3 (mg/g)	Lv4 (mg/g)	Lv5 (mg/g)
Glu	0.44 ± 0.01^a	0.32 ± 0.05^bc	0.35 ± 0.06^b	0.30 ± 0.03^bc	0.26 ± 0.02^c	0.18 ± 0.01^d
Ser	0.32 ± 0.01^b	0.32 ± 0.02^b	0.34 ± 0.03^a	0.28 ± 0.02^bc	0.24 ± 0.01^c	0.20 ± 0.01^c
Gly	0.27 ± 0.00^a	0.25 ± 0.02^b	0.25 ± 0.01^b	0.21 ± 0.01^c	0.17 ± 0.00^d	0.17 ± 0.00^d
Thr	2.68 ± 0.02^a	1.97 ± 0.13^bc	2.07 ± 0.09^b	1.89 ± 0.57^bc	1.87 ± 0.37^c	1.18 ± 0.17^d
Ala	1.09 ± 0.01^a	0.96 ± 0.02^b	0.92 ± 0.05^b	0.82 ± 0.06^c	0.73 ± 0.04^d	0.62 ± 0.01^e
Arg	0.28 ± 0.01^a	0.21 ± 0.02^bc	0.23 ± 0.03^b	0.20 ± 0.01^bc	0.19 ± 0.01^c	0.16 ± 0.01^d
His	5.20 ± 0.02^a	5.05 ± 0.07^b	4.85 ± 0.27^b	4.45 ± 0.39^bc	3.72 ± 0.49^c	3.94 ± 0.16^c
Cys	0.02 ± 0.01^a	0.04 ± 0.00^a	0.04 ± 0.00^a	0.04 ± 0.00^a	0.04 ± 0.00^a	0.04 ± 0.01^a
Val	0.22 ± 0.00^a	0.17 ± 0.02^b	0.17 ± 0.01^b	0.14 ± 0.01^c	0.12 ± 0.00^cd	0.10 ± 0.01^d
Met	0.19 ± 0.00^a	0.15 ± 0.01^b	0.14 ± 0.02^b	0.11 ± 0.00^c	0.10 ± 0.01^c	0.09 ± 0.00^c
Ile	0.20 ± 0.01^a	0.14 ± 0.02^b	0.14 ± 0.02^b	0.11 ± 0.01^c	0.08 ± 0.01^d	0.08 ± 0.01^d
Leu	0.29 ± 0.00^a	0.23 ± 0.03^bc	0.24 ± 0.02^b	0.19 ± 0.01^c	0.16 ± 0.01^d	0.14 ± 0.01^d
Phe	0.17 ± 0.00^a	0.14 ± 0.01^b	0.14 ± 0.02^b	0.14 ± 0.01^b	0.11 ± 0.01^b	0.12 ± 0.01^b
Tyr	0.24 ± 0.01^a	0.18 ± 0.01^bc	0.20 ± 0.02^b	0.15 ± 0.01^c	0.13 ± 0.01^d	0.12 ± 0.01^d
Lys	0.26 ± 0.00^a	0.18 ± 0.02^b	0.20 ± 0.03^b	0.16 ± 0.00^c	0.14 ± 0.01^cd	0.12 ± 0.00^d
Trp	0.07 ± 0.00^a	0.06 ± 0.00^a	0.04 ± 0.01^a	0.05 ± 0.01^a	0.04 ± 0.00^a	0.03 ± 0.00^a
Different superscripts between columns represent significant differences between cultivars (p < 0.05). Lv1−Lv5 represents the center temperature of beef at 50, 58, 66, 73, and 80 °C, respectively.

Table 1.

Free amino acids in beef samples with different levels of doneness.

Compounds	Raw beef (mg/g)	Lv1 (mg/g)	Lv2 (mg/g)	Lv3 (mg/g)	Lv4 (mg/g)	Lv5 (mg/g)
Glu	0.49 ± 0.03^a	0.35 ± 0.01^b	0.36 ± 0.02^b	0.30 ± 0.09^c	0.25 ± 0.06^c	0.23 ± 0.09^c
Ser	0.80 ± 0.04^a	0.52 ± 0.05^b	0.52 ± 0.03^b	0.47 ± 0.02^b	0.22 ± 0.16^c	0.36 ± 0.03^bc
Gly	0.16 ± 0.01^a	0.15 ± 0.02^a	0.16 ± 0.01^a	0.12 ± 0.02^ab	0.08 ± 0.03^b	0.12 ± 0.02^ab
Thr	1.67 ± 0.10^a	1.21 ± 0.16^b	1.18 ± 0.05^b	1.17 ± 0.24^b	1.06 ± 0.10^c	0.92 ± 0.14^c
Ala	1.12 ± 0.04^a	0.73 ± 0.08^b	0.62 ± 0.07^bc	0.54 ± 0.04^cd	0.42 ± 0.08^d	0.42 ± 0.05^d
Arg	2.21 ± 0.13^a	1.70 ± 0.19^b	1.70 ± 0.04^b	1.72 ± 0.03^b	1.66 ± 0.09^c	1.62 ± 0.30^c
His	9.37 ± 0.72^a	9.66 ± 0.45^a	9.41 ± 0.09^a	8.94 ± 0.53^ab	7.82 ± 0.27^bc	8.28 ± 0.43^c
Cys	0.48 ± 0.06^a	0.42 ± 0.07^a	0.39 ± 0.12^a	0.34 ± 0.02^b	0.42 ± 0.08^a	0.42 ± 0.00^a
Val	2.34 ± 0.23^a	1.56 ± 0.16^b	1.40 ± 0.06^b	1.36 ± 0.07^b	1.39 ± 0.17^b	1.44 ± 0.20^b
Met	1.48 ± 0.11^a	1.01 ± 0.17^b	0.79 ± 0.13^bc	0.70 ± 0.08^bc	0.50 ± 0.09^d	0.55 ± 0.15^d
Ile	3.47 ± 0.38^a	2.71 ± 0.16^b	2.52 ± 0.02^b	2.34 ± 0.12^b	2.25 ± 0.14^b	2.21 ± 0.28^b
Leu	8.29 ± 1.71^a	5.97 ± 0.40^b	5.55 ± 0.18^b	5.08 ± 0.17^b	4.93 ± 0.13^c	4.88 ± 0.09^c
Phe	1.37 ± 0.21^a	1.33 ± 0.10^a	1.11 ± 0.16^ab	1.13 ± 0.04^bc	0.91 ± 0.16^c	0.76 ± 0.17^cd
Tyr	0.66 ± 0.09^a	0.27 ± 0.03^b	0.20 ± 0.03^bc	0.11 ± 0.05^cd	0.08 ± 0.05^d	0.06 ± 0.02^d
Lys	2.44 ± 0.22^a	1.99 ± 0.05^b	2.01 ± 0.10^b	1.78 ± 0.08^c	1.67 ± 0.26^c	1.83 ± 0.23^c
Trp	0.49 ± 0.24^a	0.40 ± 0.08^a	0.43 ± 0.08^a	0.29 ± 0.04^a	0.41 ± 0.03^a	0.37 ± 0.07^a
Different superscripts between columns represent significant differences between cultivars (p < 0.05). Lv1−Lv5 represents the center temperature of beef at 50, 58, 66, 73, and 80 °C, respectively.

Table 2.

Free amino acids in beef hydrolysate with different doneness.

Number	Discriminant factor (mg/g)
Number	BAA	AAA	HAA	SAA	ARAA	TAA	AR	DR
1	6.05	0.45	1.46	0.23	0.52	12.53	0	0
2	6.01	0.48	1.46	0.21	0.50	12.57	0	0
3	5.77	0.43	1.39	0.22	0.50	11.93	0	0
4	5.73	0.45	1.39	0.20	0.48	11.97	0	0
5	4.52	0.33	1.57	0.27	0.55	11.17	1	1
6	5.46	0.30	1.05	0.20	0.37	10.29	1	1
7	5.47	0.28	0.96	0.18	0.36	10.04	1	1
8	5.40	0.40	1.17	0.21	0.38	10.75	1	2
9	4.56	0.41	1.41	0.25	0.53	10.72	1	1
10	4.66	0.33	1.39	0.26	0.46	10.47	2	2
11	5.73	0.42	1.25	0.20	0.45	11.13	2	0
12	5.14	0.33	1.01	0.18	0.33	9.93	2	2
13	4.96	0.29	0.98	0.16	0.35	9.88	2	3
14	4.66	0.34	1.40	0.26	0.50	10.49	2	2
15	4.26	0.33	1.29	0.20	0.48	10.25	3	3
16	4.10	0.33	1.37	0.32	0.45	10.27	3	3
17	5.02	0.31	0.96	0.16	0.35	9.26	3	3
18	5.12	0.26	0.87	0.15	0.33	8.84	3	3
19	4.26	0.34	0.88	0.15	0.33	9.61	3	3
20	4.26	0.27	1.21	0.21	0.39	9.62	4	4
21	4.20	0.27	1.18	0.23	0.40	9.48	4	4
22	4.74	0.23	0.76	0.16	0.28	8.26	4	4
23	3.87	0.26	0.71	0.13	0.26	8.36	4	4
24	3.53	0.29	0.74	0.14	0.30	7.67	4	4
25	3.65	0.22	0.91	0.17	0.32	8.04	5	5
26	4.43	0.18	0.65	0.12	0.27	7.22	5	5
27	4.16	0.18	0.71	0.13	0.27	7.48	5	5
28	4.08	0.19	0.69	0.14	0.27	7.19	5	5
29	3.60	0.23	0.98	0.18	0.30	8.06	5	5
AR (Actual result), DR (Results of discrimination). Basic amino acids (BAA), acidic amino acids (AAA), hydrophobic amino acids (HAA), sulfur amino acids (SAA), aromatic amino acids (ARAA), total amino acids (TAA).

Table 3.

Classification results of discriminant analysis (free amino acids without enzymolysis).

Number	Discriminant factor (mg/g)
Number	BAA	AAA	HAA	SAA	ARAA	TAA	AR	DR
1	12.93	0.46	15.3	1.78	2.16	32.7	0	0
2	15.52	0.55	18.36	2.14	2.59	39.57	0	0
3	14.1	0.49	19.54	1.98	2.7	38.7	0	0
4	15.09	0.53	20.9	2.12	2.89	40.96	0	0
5	13.6	0.35	12.53	1.34	1.94	29.43	1	2
6	14.03	0.34	14.54	1.74	2.12	32.41	1	1
7	12.41	0.38	12.66	1.21	1.94	28.1	1	2
8	12.04	0.63	12.82	2.28	3.32	30.51	1	1
9	12.24	0.6	13.79	3.01	2.88	31.9	1	2
10	12.98	0.37	11.93	1.07	1.69	28.13	2	3
11	13.42	0.34	12.35	1.07	1.99	28.99	2	3
12	12.95	0.39	11.7	1.4	1.51	27.91	2	1
13	11.55	0.54	13.25	2	3.11	29.17	2	2
14	11.81	0.58	13.3	2.38	3.61	29.29	2	4
15	12.32	0.17	11.27	1.12	1.5	26.37	3	2
16	13.03	0.32	10.38	0.87	1.5	25.97	3	3
17	11.99	0.4	11.37	1.12	1.59	26.78	3	2
18	11.84	0.5	12.81	1.84	3.22	29.06	3	3
19	11.35	0.56	12.34	2.06	2.65	29.98	3	3
20	11.03	0.26	9.33	0.77	1.15	22.52	4	5
21	11.24	0.32	11.49	1	1.57	25.19	4	5
22	11.17	0.17	10.58	1	1.45	24.5	4	4
23	10.51	0.5	10.16	2.01	2.66	25.28	4	4
24	11.02	0.12	10.85	2.5	2.72	26.23	4	4
25	11.76	0.27	10.97	0.96	1.35	25.4	5	5
26	10.55	0.1	8.68	0.79	1.02	21.28	5	5
27	12.88	0.31	11.16	1.15	1.21	26.71	5	2
28	8.84	0.28	8.36	1.3	1.74	20.34	5	5
29	10.36	0.44	8.66	1.11	2.11	22.53	5	5
Basic amino acids (BAA), acidic amino acids (AAA), hydrophobic amino acids (HAA), sulfur amino acids (SAA), aromatic amino acids (ARAA), total amino acids (TAA).

Table 4.

Classification results of distance discriminant analysis (free amino acids after enzymolysis).

AR DR

0 1 2 3 4 5

0 4 0 0 0 0 0

1 0 4 1 0 0 0

2 0 0 5 0 0 0

3 0 0 0 5 0 0

4 0 0 0 0 5 0

5 0 0 0 0 0 5

AR (Actual result), DR (Results of discrimination).

Table 5.
Results of discriminating data without enzymatic decomposition.
AR DR

0 1 2 3 4 5

0 4 0 0 0 0 0

1 0 5 0 0 0 0

2 0 0 5 0 0 0

3 0 0 0 5 0 0

4 0 0 0 0 5 0

5 0 0 0 1 0 4

AR (Actual result), DR (Results of discrimination).

Table 6.
The discriminant results of enzyme decomposition data.