Variation in oil quality and content of low molecular lipophilic compounds in chia seed oils

Figures & data

Table 1. Seed material used in the study.

Sample	Origin country	Shelf life
1.	Argentina	08.2018
2.	Argentina	No data
3.	Argentina	02.2018
4.	Argentina	08.2019
5.	Argentina	04.2019
6.	Paraguay	05.2018
7.	Paraguay	07.2018
8.	Paraguay	12.2018
9.	Paraguay	12.2018
10.	Uganda	08.2018
11.	Bolivia	07.2018
12.	Bolivia	02.2018
13.	Peru	04.2018
14.	Peru	10.2017
15.	Out of EU	01.2019

Table 2. Oil recovery from chia seeds and the fatty acid composition of chia seed oils.

Sample	Oil yield (g/100 g of dry basis)	Fatty acid composition (%)									n-6/n-3 ratio
		Palmitic	Stearic	Oleic	Linoleic	α-Linolenic	Unidentified minor fatty acids
		(C16:0)	(C18:0)	(C18:1, n-9)	(C18:2, n-6)	(C18:3, n-3)	1	2	3	4
		Retention time (min)
		3.49	4.76	5.04	5.89	6.42	3.89	5.35	6.03	6.65
1	34.0 ± 0.23^a	8.80 ± 0.22^bc	3.75 ± 0.20^bcd	8.19 ± 0.26^abcd	22.49 ± 0.39^a	55.92 ± 1.08^abc	0.19 ± 0.01^a	0.13 ± 0.01^b	0.27 ± 0.03^b	0.29 ± 0.02^ab	0.40 ± 0.01^a
2	33.8 ± 0.30^a	8.72 ± 0.13^bc	3.33 ± 0.15^abc	8.08 ± 0.28^abcd	23.12 ± 0.34^a	55.95 ± 0.88^abc	0.16 ± 0.01^a	0.12 ± 0.01^ab	0.27 ± 0.06^b	0.27 ± 0.04^ab	0.41 ± 0.01^a
3	34.2 ± 0.30^ab	8.66 ± 0.05^abc	3.10 ± 0.11^ab	7.91 ± 0.35^abc	23.06 ± 0.32^a	56.62 ± 1.00^abc	0.13 ± 0.06^a	0.06 ± 0.00^ab	0.17 ± 0.03^ab	0.31 ± 0.08^b	0.41 ± 0.01^a
4	35.7 ± 0.20^c	8.42 ± 0.14^abc	3.77 ± 0.16^bcd	8.37 ± 0.16^abcd	22.53 ± 0.28^a	56.22 ± 0.77^abc	0.14 ± 0.01^a	0.10 ± 0.01^ab	0.24 ± 0.02^ab	0.22 ± 0.01^ab	0.40 ± 0.01^a
5	35.0 ± 0.05^bc	7.75 ± 0.13^a	2.85 ± 0.27^a	6.79 ± 0.64^a	21.80 ± 1.11^a	60.48 ± 2.28^c	0.11 ± 0.03^a	0.10 ± 0.04^ab	0.09 ± 0.04^ab	0.05 ± 0.02^a	0.36 ± 0.03^a
6	34.3 ± 0.27^ab	8.79 ± 0.45^bc	3.99 ± 0.37^cd	8.85 ± 0.75^cd	23.05 ± 0.72^a	54.69 ± 2.45^ab	0.14 ± 0.02^a	0.06 ± 0.01^ab	0.21 ± 0.01^ab	0.23 ± 0.13^ab	0.42 ± 0.03^a
7	35.5 ± 0.09^c	8.45 ± 0.11^abc	3.95 ± 0.11^cd	8.99 ± 0.21^cd	22.19 ± 0.17^a	55.87 ± 0.24^abc	0.18 ± 0.01^a	0.06 ± 0.04^ab	0.18 ± 0.07^ab	0.15 ± 0.09^ab	0.40 ± 0.00^a
8	33.8 ± 0.21^a	9.07 ± 0.04^c	4.19 ± 0.01^de	8.27 ± 0.06^abcd	21.90 ± 0.04^a	55.93 ± 0.24^abc	0.17 ± 0.01^a	0.11 ± 0.01^ab	0.16 ± 0.09^ab	0.23 ± 0.00^ab	0.39 ± 0.00^a
9	34.5 ± 0.46^ab	8.86 ± 0.04^bc	4.05 ± 0.11^cd	8.21 ± 0.08^abcd	22.01 ± 0.02^a	56.32 ± 0.24^abc	0.16 ± 0.01^a	0.07 ± 0.05^ab	0.20 ± 0.01^ab	0.14 ± 0.04^ab	0.39 ± 0.00^a
10	33.7 ± 0.17^a	8.80 ± 0.07^bc	4.93 ± 0.13^e	9.73 ± 0.20^d	21.64 ± 0.04^a	54.35 ± 0.44^a	0.17 ± 0.01^a	0.08 ± 0.01^ab	0.14 ± 0.01^ab	0.16 ± 0.01^ab	0.40 ± 0.00^a
11	34.9 ± 0.15^bc	9.00 ± 0.12^c	3.45 ± 0.11^abcd	8.36 ± 0.15^abcd	23.21 ± 0.05^a	55.14 ± 0.54^abc	0.20 ± 0.02^a	0.15 ± 0.04^b	0.25 ± 0.05^ab	0.27 ± 0.08^ab	0.42 ± 0.00^a
12	34.5 ± 0.14^ab	8.55 ± 0.06^abc	4.03 ± 0.11^cd	8.82 ± 0.15^cd	22.72 ± 0.11^a	55.37 ± 0.35^abc	0.14 ± 0.03^a	0.12 ± 0.02^ab	0.12 ± 0.07^ab	0.14 ± 0.06^ab	0.41 ± 0.00^a
13	35.8 ± 0.08^c	8.01 ± 0.44^ab	3.08 ± 0.26^ab	7.07 ± 0.75^ab	21.74 ± 1.04^a	59.84 ± 2.62^bc	0.09 ± 0.05^a	0.02 ± 0.00^a	0.08 ± 0.04^a	0.09 ± 0.06^ab	0.36 ± 0.03^a
14	34.0 ± 0.30^a	8.71 ± 0.16^bc	3.82 ± 0.09^bcd	8.22 ± 0.14^abcd	22.00 ± 0.06^a	56.74 ± 0.42^abc	0.17 ± 0.05^a	0.02 ± 0.00^a	0.15 ± 0.01^ab	0.19 ± 0.06^ab	0.39 ± 0.00^a
15	33.8 ± 0.28^a	8.64 ± 0.48^abc	4.12 ± 0.45^cde	8.53 ± 0.84^bcd	22.49 ± 0.49^a	55.90 ± 2.38^abc	0.14 ± 0.04^a	0.03 ± 0.01^a	0.10 ± 0.04^ab	0.07 ± 0.01^ab	0.40 ± 0.03^a
All samples	34.49 ± 0.74	8.61 ± 0.35	3.76 ± 0.53	8.29 ± 0.72	22.39 ± 0.54	56.35 ± 1.68	0.15 ± 0.03	0.08 ± 0.04	0.17 ± 0.06	0.19 ± 0.08	0.40 ± 0.02
CV (%)	2.14	4.06	14.11	8.64	2.43	2.98	19.33	51.29	36.53	44.17	4.51

a, b, … - Means in the same column for all variants followed by different letters are significantly different (p ≤ 0.05).

Values are mean  ±  SD (n = 3);

SD – Standard deviation;

CV – Coefficient of variance

Table 3. Phytosterol contents (mg/kg) in chia seed oils.

Sample	Campesterol	Stigmasterol	β-sitosterol	25-hydroxy-24-methylcholesterol	Other sterol-like compounds	Total
1	827 ± 20.5^f	301 ± 5.7^abc	3915 ± 77.1^abcde	652 ± 14.0^cd	1407 ± 184.2^abc	7103 ± 78.3^bcd
2	813 ± 14.8^ef	331 ± 18.7^d	4164 ± 64.2^de	631 ± 14.4^cd	1425 ± 95.8^abc	7364 ± 207.9^de
3	785 ± 5.0^cde	316 ± 4.6^cd	4082 ± 43.0^cde	651 ± 11.1^cd	1328 ± 20.1^ab	7161 ± 43.5^cd
4	725 ± 6.1^ab	276 ± 1.8^a	3684 ± 94.2^a	575 ± 5.0^ab	1530 ± 28.2^bcd	6790 ± 53.0^abc
5	760 ± 0.5^bc	301 ± 0.8^abc	4003 ± 18.0^abcde	661 ± 8.4^cd	1378 ± 5.1^abc	7104 ± 31.2^bcd
6	784 ± 13.1^cde	304 ± 3.0^bc	4211 ± 151.9^a	675 ± 1.7^d	1690 ± 21.5^d	7665 ± 138.7^e
7	766 ± 16.3^bcd	284 ± 4.7^ab	4061 ± 4.3^bcde	635 ± 23.0^cd	1518 ± 17.3^abcd	7265 ± 19.6^de
8	734 ± 6.2^ab	289 ± 5.7^ab	3832 ± 55.5^abcd	622 ± 14.2^bc	1492 ± 16.0^abcd	6969 ± 13.4^abcd
9	735 ± 7.3^ab	281 ± 7.5^ab	3713 ± 10.8^a	627 ± 10.2^bcd	1491 ± 8.6^abcd	6847 ± 14.8^abc
10	783 ± 4.2^bcd	296 ± 5.8^abc	4060 ± 73.0^bcde	618 ± 17.2^abc	1601 ± 41.4^cd	7358 ± 4.5^de
11	709 ± 2.5^a	302 ± 6.0^bc	3733 ± 31.0^ab	626 ± 6.9^bcd	1354 ± 23.9^ab	6724 ± 56.4^ab
12	763 ± 2.8^bcd	296 ± 1.5^abc	3853 ± 53.3^abcd	637 ± 19.0^cd	1445 ± 15.5^abc	6993 ± 61.2^abcd
13	693 ± 1.3^a	298 ± 6.1^abc	3804 ± 92.6^abc	569 ± 6.4^a	1289 ± 61.6^a	6653 ± 17.3^a
14	804 ± 17.6^def	305 ± 2.1^bc	3895 ± 108.5^abcde	654 ± 14.8^cd	1510 ± 4.7^abcd	7167 ± 134.1^cd
15	730 ± 8.6^ab	279 ± 0.0^ab	3676 ± 166.2^a	620 ± 14.8^abc	1452 ± 36.7^abcd	6757 ± 226.4^ab
Allsamples	761 ± 39.4	297 ± 15.0	3912 ± 183.4	630 ± 30.1	1461 ± 111.6	7061 ± 286.7
CV (%)	5.18	5.05	4.69	4.77	7.64	4.06

a, b, … - Means in the same column for all variants followed by different letters are significantly different (p ≤ 0.05).

Values are mean ± SD (n = 3);

SD – Standard deviation;

CV – Coefficient of variance

Table 4. Tocopherol contents (mg/kg) in chia seed oils.

Sample	α-tocopherol	γ-tocopherol	δ-tocopherol	Total
1	nd^a	118 ± 3.5^a	10.5 ± 1.44^a	129 ± 4.9^a
2	25.8 ± 5.40^b	541 ± 5.1^d	14.8 ± 0.99^abcd	582 ± 1.3^d
3	35.1 ± 0.09^cde	668 ± 0.9^hi	18.7 ± 2.14^cde	721 ± 1.1^ij
4	30.3 ± 0.35^bc	597 ± 6.3^ef	19.3 ± 2.10^de	647 ± 8.8^fg
5	32.9 ± 1.85^cd	618 ± 1.6^g	15.1 ± 1.06^abcde	666 ± 2.4^g
6	32.5 ± 1.29^cd	658 ± 1.0^hi	20.8 ± 0.86^e	712 ± 3.1^hi
7	37.4 ± 0.62^de	649 ± 12.1^h	19.3 ± 2.08^de	706 ± 13.6^hi
8	30.6 ± 0.36^bc	307 ± 2.4^b	12.2 ± 0.68^ab	350 ± 2.1^b
9	26.2 ± 0.21^b	439 ± 0.0^c	15.5 ± 1.28^abcde	481 ± 1.5^c
10	40.3 ± 0.31^e	676 ± 3.0^i	18.7 ± 2.90^cde	735 ± 0.2^j
11	34.4 ± 0.13^cde	595 ± 0.5^ef	12.1 ± 0.11^ab	641 ± 0.5^ef
12	31.6 ± 0.13^bcd	609 ± 2.4^fg	15.3 ± 1.28^abcde	656 ± 3.5^fg
13	34.5 ± 0.11^cde	601 ± 0.1^fg	16.5 ± 0.85^bcde	652 ± 1.1^fg
14	34.7 ± 1.23^cde	648 ± 3.9^h	13.8 ± 0.04^abcd	697 ± 5.1^h
15	30.8 ± 0.19^bc	579 ± 11.3^e	13.2 ± 0.06^abc	623 ± 11.4^e
Allsamples	30.5 ± 9.15	553 ± 151.9	15.7 ± 3.22	600 ± 161.9
CV (%)	30.02	27.45	20.47	27.00

a, b, … - Means in the same column for all variants followed by different letters are significantly different (p ≤ 0.05).

nd – not detected

Values are mean ±  SD (n = 3);

SD – Standard deviation;

CV – Coefficient of variance

Table 5. Polyphenol, carotenoid, and squalene contents in chia seed oils (mg/kg).

Sample	Carotenoids					Polyphenols	Squalene
	Lutein	β-carotene	9-cis-β-carotene	Unidentified carotenoid-like compounds	Total carotenoids
1	0.36 ± 0.01^def	0.92 ± 0.02^d	0.32 ± 0.01^f	0.63 ± 0.01^bc	2.23 ± 0.01^d	0.72 ± 0.00^a	29.39 ± 1.82^f
2	0.32 ± 0.02^cde	1.50 ± 0.07^f	0.29 ± 0.01^e	0.68 ± 0.04^bcd	2.79 ± 0.02^e	0.35 ± 0.00^a	29.86 ± 1.77^f
3	0.32 ± 0.03^cde	0.69 ± 0.03^bc	traces ^a	0.72 ± 0.04^cde	1.72 ± 0.04^bc	16.93 ± 0.00^gh	11.74 ± 0.50^ab
4	0.00 ± 0.00^a	1.80 ± 0.09^g	traces ^a	0.48 ± 0.02^a	2.28 ± 0.07^d	20.74 ± 1.29^h	14.87 ± 0.79^abcd
5	0.20 ± 0.05^b	0.37 ± 0.03^a	0.14 ± 0.00^b	0.66 ± 0.03^bcd	1.36 ± 0.01^a	5.76 ± 0.11^bcd	29.20 ± 1.29^f
6	0.35 ± 0.01^cdef	1.12 ± 0.04^e	traces ^a	0.71 ± 0.00^cd	2.17 ± 0.03^d	14.42 ± 3.33^fg	13.06 ± 0.33^abc
7	0.41 ± 0.00^f	1.41 ± 0.08^f	0.26 ± 0.02^cd	0.70 ± 0.07^cd	2.79 ± 0.13^e	11.67 ± 1.68^ef	11.08 ± 0.18^a
8	0.27 ± 0.02^bc	0.53 ± 0.02^ab	traces ^a	0.54 ± 0.01^ab	1.34 ± 0.05^a	9.01 ± 0.78^de	11.55 ± 0.01^ab
9	0.30 ± 0.02^cd	0.69 ± 0.01^bc	traces ^a	0.72 ± 0.01^cde	1.71 ± 0.00^bc	25.32 ± 1.45^i	14.67 ± 0.59^abcd
10	0.27 ± 0.02^bc	0.99 ± 0.01^de	0.27 ± 0.01^de	0.78 ± 0.04^de	2.30 ± 0.06^d	20.16 ± 0.62^h	17.81 ± 1.17^de
11	0.57 ± 0.02^g	1.52 ± 0.03^f	0.39 ± 0.00^g	1.50 ± 0.04^f	3.98 ± 0.08^f	1.76 ± 0.20^ab	18.92 ± 1.98^e
12	0.29 ± 0.02^cd	0.93 ± 0.00^d	traces ^a	0.70 ± 0.06^cd	1.92 ± 0.08^c	1.39 ± 0.22^ab	12.22 ± 0.40^ab
13	0.29 ± 0.01^cd	0.70 ± 0.03^c	traces ^a	0.65 ± 0.01^bcd	1.65 ± 0.05^b	2.21 ± 0.24^abc	18.22 ± 0.03^de
14	0.40 ± 0.01^ef	1.06 ± 0.00^de	traces ^a	0.84 ± 0.02^e	2.30 ± 0.03^d	6.36 ± 0.16^cd	16.88 ± 0.23^cde
15	0.31 ± 0.05^cde	1.13 ± 0.02^e	0.24 ± 0.00^c	0.72 ± 0.00^cde	2.41 ± 0.07^d	8.15 ± 0.16^de	15.53 ± 0.23^bcde
All samples	0.31 ± 0.12	1.02 ± 0.40	0.11 ± 0.15	0.73 ± 0.23	2.20 ± 0.66	9.66 ± 8.09	17.67 ± 6.52
CV	38.97	39.31	134.96	31.16	29.93	83.72	36.93

a, b, … - Means in the same column for all variants followed by different letters are significantly different (p ≤ 0.05).

Values are mean  ±  SD (n = 3);

SD – Standard deviation;

CV – Coefficient of variance

Table 6. Quality features of chia seed oils.

Sample	AV(mg KOH/g)	PV(mEqO2/kg)	Induction time (h)	p-Anisidine value(-)	Conjugated dienes(%)	Conjugated trienes(%)
1	25.69 ± 1.25^f	7.30 ± 0.14^h	0.14 ± 0.00^a	14.59 ± 0.44^h	0.344 ± 0.009^j	0.013 ± 0.000^g
2	3.51 ± 0.00^bc	6.30 ± 0.14^g	1.87 ± 0.01^c	2.71 ± 0.07^ef	0.199 ± 0.020^def	0.002 ± 0.000^bcde
3	1.56 ± 0.24^a	3.40 ± 0.28^de	2.42 ± 0.23^ef	2.94 ± 0.14^ef	0.158 ± 0.001^a	0.002 ± 0.000^bcde
4	7.77 ± 0.48^de	2.60 ± 0.28^bcd	2.94 ± 0.04^g	7.95 ± 0.36^g	0.220 ± 0.001^fg	0.000 ± 0.000^ab
5	2.91 ± 0.24^abc	2.70 ± 0.14^bcd	2.32 ± 0.08^def	1.45 ± 0.18^bc	0.174 ± 0.000^ab	0.000 ± 0.000^a
6	2.05 ± 0.00^ab	4.40 ± 0.00^f	2.06 ± 0.01^cde	0.53 ± 0.01^a	0.176 ± 0.001^abc	0.003 ± 0.001^cde
7	2.10 ± 0.00^ab	3.40 ± 0.28^de	2.97 ± 0.30^g	2.67 ± 0.15^ef	0.213 ± 0.001^efg	0.002 ± 0.001^abcd
8	6.33 ± 0.24^d	4.10 ± 0.42^ef	0.21 ± 0.12^a	14.57 ± 0.09^h	0.320 ± 0.000^i	0.001 ± 0.000^abc
9	9.58 ± 0.97^e	2.00 ± 0.00^ab	1.02 ± 0.01^b	3.24 ± 0.06^f	0.233 ± 0.000^gh	0.002 ± 0.000^abcde
10	1.88 ± 0.24^ab	2.10 ± 0.14^ab	3.45 ± 0.05^h	2.17 ± 0.02^cde	0.197 ± 0.000^cde	0.002 ± 0.001^abcd
11	3.55 ± 0.24^bc	2.00 ± 0.00^ab	1.98 ± 0.04^cd	1.81 ± 0.01^bcd	0.157 ± 0.000^a	0.002 ± 0.000^cde
12	2.20 ± 0.24^abc	1.60 ± 0.28^a	2.04 ± 0.03^cde	1.19 ± 0.19^ab	0.230 ± 0.000^gh	0.006 ± 0.000^f
13	3.33 ± 0.25^abc	3.00 ± 0.28^cd	1.87 ± 0.06^c	1.38 ± 0.17^b	0.182 ± 0.001^bcd	0.003 ± 0.000^de
14	1.86 ± 0.24^ab	2.00 ± 0.28^ab	2.58 ± 0.04^fg	2.34 ± 0.02^de	0.247 ± 0.001^h	0.006 ± 0.000^f
15	3.98 ± 0.24^c	2.40 ± 0.00^abc	2.50 ± 0.04^f	1.70 ± 0.32^bcd	0.203 ± 0.001^def	0.004 ± 0.000^e
All samples	5.22 ± 6.04	3.29 ± 1.63	2.02 ± 0.93	4.08 ± 4.50	0.217 ± 0.054	0.003 ± 0.003
CV (%)	115.63	49.51	45.97	110.36	24.60	97.95

a, b, … - Means in the same column for all variants followed by different letters are significantly different (p ≤ 0.05).

Values are mean  ±  SD (n = 3);

SD – Standard deviation;

CV – Coefficient of variance

Figure 1. Two-dimensional graph for a PCA (correlation circle for the composition and quality features of chia seed oils).