The present study was carried out to characterize the FA profile of sheep cheese marketed in Chile. Fifty-eight cheeses were collected from supermarkets of 5 different Chilean cities including 34 sheep cheeses, 7 from goat's milk, 11 from cow's milk, 4 from a mixture of sheep, goat and cow's milk and 2 from a mixture of sheep and cow's milk. Compared to the cow and goat cheese (3.4 and 2.5 g·100g−1), the sheep cheese (3.8 g·100g−1) contained higher contents of C18:1t. The saturated and polyunsatured FA contents were greater in goat cheese than in sheep and cow cheese. The n6/n3 ratio was greater in goat (6.1) cheese than in sheep and cow cheese (3.8 and 5.2). The atherogenicity index was unaffected by cheese type, however, the thrombogenic index was lower in sheep cheese (2.8) than in goat and cow cheese (3.1 and 2.9). The n6/n3 ratio and thrombogenic index were lower in Chilean sheep cheese than in those imported from Europe. The fatty acid profile of cheese can be used to differentiate animal species from which the cheese is made and to some extent the geographical origin that may give some insight as to animal feed and production management.
In Chile there has been a significant growth in cheese production (ODEPA,
The milk fatty acid profile of ruminants can be affected by different factors such as animal species, lactation stages, feeding, and genetics (Vargas-Bello-Pérez and Garnsworthy,
Given that sheep cheese has fatty acids that may have positive effects on human health and its production could signify economic profits, the objective of the present study is to analyze the FA profile of commercial sheep cheese in Chile. The results could become the basis for developing benchmarking tools and strategies aiming at
Fifty-eight cheeses were collected from supermarkets of 5 different Chilean cities (Santiago, Rancagua, Melipilla, Viña del Mar and Puerto Natales) including 34 sheep cheeses, 7 from goat's milk, 11 from cow's milk, 4 from a mixture of sheep, goat and cow's milk and 2 from a mixture of sheep and cow's milk. The sheep cheeses were produced in Chile (23 cheeses) and imported from France (2 cheeses) and Spain (9 cheeses). After collection, the cheeses were cut in four sections at which time two cores of each cheese were obtained and stored in re-sealable bags at –80 °C for one month until further analysis.
Two cores of each cheese were used for the FA analysis. The lipids from the cheese were extracted according to a chloroform/methanol (2:1, v/v) by Folch
The samples were assigned to four groups: cow, sheep, goat and mixtures. The samples were analyzed using ANOVA and multiple comparisons of means. In order to determine which FA was responsible for the differentiation between cheeses that were made from different animal species and geographical origin a multivariate analysis was carried out using a correlation matrix between individual FA to discard those that showed very high correlations (r = >0.9) as well as those without correlations. Bartlett's test of sphericity was applied to examine the hypothesis that the variables were uncorrelated in the population and the Kaiser-Meyer-Olkin index was used to measure sampling adequacy. Hierarchical clustering was then performed and a discriminant analysis was used to verify the extent to which samples were correctly assigned to the clusters identified in the previous analysis. To check for possible differences among cheeses associated with country of origin (Chile, Spain and France) an individual analysis of variance and multiple means comparison were performed. The SPSS statistical software for Windows was used (version 15.0.0; SPSS Inc., Chicago IL, USA).
From the cheese samples analyzed, only C17:0 was not different among animal species (
Fatty acid profile (mean ± standard deviation) of cheese from different animal species (g·100g−1 of total FAME)
Fatty acid | Cow (n = 11) | Sheep (n = 34) | Goat (n = 7) | Mixture (n = 6) | P-value |
---|---|---|---|---|---|
C4:0 | 1.32±0.15 |
1.18±0.17 |
1.01±0.07 |
1.18±0.07 |
0.001 |
C6:0 | 1.08±0.05 |
1.36±0.19 |
1.44±0.11 |
1.21±0.11 |
<0.001 |
C8:0 | 0.81±0.05 |
1.62±0.29 |
2.06±0.24 |
1.29±0.25 |
<0.001 |
C10:0 | 2.17±0.23 |
5.92±1.06 |
8.44±1.22 |
4.47±1.07 |
<0.001 |
C12:0 | 2.93±0.38 |
3.99±0.59 |
4.46±0.82 |
3.18±0.54 |
<0.001 |
C14:0 | 11.1±0.62 |
11.43±1.15 |
10.53±0.82 |
10.23±1.01 |
0.028 |
C14:1c9 | 1.62±0.17 |
0.84±0.13 |
0.49±0.04 |
0.91±0.22 |
<0.001 |
C15:0 | 1.35±0.25 |
1.34±0.25 |
1.01±0.12 |
1.05±0.21 |
0.001 |
C16:0 | 31.84±3.08 |
28.55±2.33 |
29.88±1.1 |
30.9±1.87 |
<0.001 |
C16:1c9 | 2.01±0.14 |
1.4±0.39 |
0.74±0.25 |
1.37±0.36 |
<0.001 |
C17:0 | 0.73±0.12 | 0.76±0.14 | 0.69±0.10 | 0.69±0.17 | 0.418 |
C17:1n3(c10) | 0.34±0.05 |
0.36±0.07 |
0.29±0.07 |
0.32±0.07 |
0.047 |
C18:0 | 12.12±1.39 |
11.64±1.91 |
11.08±1.33 |
13.12±1.53 |
0.159 |
C18:1t | 3.36±1.65 |
3.77±1.21 |
2.47±1.26 |
2.7±0.65 |
0.050 |
C18:1n9c | 22.52±1.52 |
19.64±1.92 |
19.75±2.93 |
22.68±1.35 |
<0.001 |
C18:2n6(t9,12) | 0.41±0.07 |
0.58±0.13 |
0.52±0.23 |
0.41±0.10 |
0.001 |
C18:2n6(c9,12) | 2.15±0.41 |
2.22±0.42 |
3.22±0.43 |
2.2±0.33 |
<0.001 |
C18:3n6(c6,9,12) | 0.06±0.07 |
0.34±0.07 |
0.24±0.07 |
0.29±0.08 |
<0.001 |
C18:3n3(c9,12,15) | 0.63±0.27 |
0.96±0.34 |
0.77±0.47 |
0.55±0.33 |
0.009 |
C20:1n9(c11) | 1.26±0.67 |
1.49±0.59 |
0.74±0.29 |
0.86±0.29 |
0.005 |
Others | 0.95±0.15 |
0.6±0.24 |
0.18±0.10 |
0.39±0.11 |
<0.001 |
Short chain FA | 2.40±0.15 | 2.53±0.33 | 2.44±0.15 | 2.39±0.05 | 0.434 |
Medium chain FA | 5.91±0.65 |
11.53±1.89 |
14.96±2.06 |
8.93±1.75 |
<0.001 |
Short + medium chain FA | 5.39±0.29 |
8.14±1.34 |
10.07±1.62 |
12.94±1.53 |
<0.010 |
Long chain FA | 57.13±2.23 |
53.72±1.83 |
53.19±1.21 |
55.99±1.63 |
<0.001 |
Saturated FA | 65.45±2.57 |
67.78±2.14 |
70.6±1.84 |
67.32±2.09 |
<0.001 |
Monounsaturated FA | 31.11±2.61 |
27.51±1.93 |
24.47±2.2 |
28.83±1.85 |
<0.001 |
Polyunsaturated FA | 3.25±0.28 |
4.11±0.61 |
4.75±0.77 |
3.45±0.51 |
0.009 |
PUFA n3 | 0.63±0.27 |
0.96±0.34 |
0.77±0.47 |
0.55±0.33 |
<0.001 |
PUFA n6 | 2.62±0.43 |
3.15±0.49 |
3.98±0.46 |
2.9±0.37 |
<0.001 |
PUFA n6/ PUFA n3 | 5.17±2.82 |
3.79±1.81 |
6.09±1.79 |
6.45±2.78 |
<0.007 |
PUFA/SFA | 0.049±0.005 |
0.061±0.009 |
0.067±0.011 |
0.051±0.009 |
<0.001 |
Atherogenicity index |
2.33±0.35 | 2.49±0.35 | 2.63±0.29 | 2.34±0.32 | 0.226 |
Thrombogenic index |
2.94±0.44 |
2.81±0.28 |
3.1±0.28 |
3.09±0.34 |
0.070 |
Short-chain FA = C4:0-C6:0; Medium-chain FA = C8:0-C12:0; Short- + medium- chain FA = C4:0-C10:0; Long-chain FA = ≥C14:0;
Means in the same row with different superscripts are different (P<0.05).
Atherogenicity index = [(12:0 + 4(14:0) + 16:0] / [(n6 + n3) PUFA + 18:1 + ΣMUFA] (Ulbricht and Southgate,
Thrombogenic index = (14:0 + 16:0 + 18:0) / [(0.5×18:1) + 0.5(ΣMUFA) + 0.5(n6PUFA) + 3(n3PUFA) + (n3PUFA/n6PUFA)] (Ulbricht and Southgate,
Compared with cow and goat, sheep cheese had higher contents of C18:1
Interestingly, the C18:1
Fatty acid profile (mean ± standard deviation) of sheep cheese from different geographical origins (g·100g−1 of total FAME)
Fatty acid | Chile (n = 23) | France (n = 2) | Spain (n = 9) | P-value |
---|---|---|---|---|
C4:0 | 1.09±0.16 |
1.18±0.19 |
1.32±0.10 |
0.003 |
C6:0 | 1.3±0.21 |
1.54±0.10 |
1.42±0.13 |
0.122 |
C8:0 | 1.53±0.31 | 1.94±0.19 | 1.7±0.19 | 0.087 |
C10:0 | 5.61±1.13 | 7.15±0.29 | 6.23±0.71 | 0.072 |
C12:0 | 3.84±0.60 | 4.67±0.07 | 4.13±0.45 | 0.090 |
C14:0 | 11.6±1.25 | 11.81±0.10 | 10.85±0.64 | 0.215 |
C14:1c9 | 0.92±0.09 |
0.69±0.01 |
0.7±0.06 |
<0.001 |
C15:0 | 1.46±0.21 |
1.08±0.01 |
1.09±0.08 |
<0.001 |
C16:0 | 28.88±2.79 | 28.25±0.55 | 27.8±1.20 | 0.527 |
C16:1c9 | 1.52±0.40 | 1.3±0.02 | 1.19±0.27 | 0.090 |
C17:0 | 0.8±0.15 |
0.66±0.02 |
0.67±0.04 |
0.037 |
C17:1n3(c10) | 0.39±0.07 |
0.29±0.04 |
0.30±0.02 |
0.001 |
C18:0 | 11.14±2.09 | 12±0.47 | 12.81±1.22 | 0.093 |
C18:1t | 4.26±1.18 |
2.84±0.48 |
2.95±0.59 |
0.007 |
C18:1n9c | 19.1±1.89 |
19.27±0.07 |
21.38±1.14 |
0.007 |
C18:2n6(t9,12) | 0.59±0.10 | 0.41±0.08 | 0.56±0.12 | 0.075 |
C18:2n6(c9,12) | 1.98±0.26 |
2.46±0.05 |
2.69±0.29 |
<0.001 |
C18:3n6(c6,9,12) | 0.34±0.08 | 0.3±0.03 | 0.35±0.05 | 0.628 |
C18:3n3(c9,12,15) | 1.1±0.25 |
0.78±0.09 |
0.59±0.14 |
<0.001 |
C20:1n9(c11) | 1.86±0.42 |
0.93±0.19 |
0.83±0.15 |
<0.001 |
Others | 0.68±0.24 |
0.48±0.05 |
0.43±0.13 |
0.014 |
Short chain FA | 2.39±0.33 |
2.72±0.08 |
2.74±0.23 |
0.019 |
Medium chain FA | 10.98±1.97 | 13.76±0.55 | 12.05±1.33 | 0.070 |
Short + medium chain FA | 9.54±1.7 | 10.67±1.09 | 11.81±0.4 | 0.050 |
Long chain FA | 53.88±2.03 | 53.8±1.15 | 53.22±1.49 | 0.676 |
Saturated FA | 67.25±2.15 | 70.27±0.68 | 68.01±1.21 | 0.097 |
Monounsaturated FA | 28.05±1.93 | 25.30±0.63 | 27.37±1.06 | 0.091 |
Polyunsaturated FA | 4.02±0.57 | 3.95±0.10 | 4.2±0.48 | 0.678 |
PUFA n3 | 1.09±0.25 |
0.78±0.10 |
0.59±0.14 |
<0.001 |
PUFA n6 | 2.92±0.36 |
3.17±0.03 |
3.61±0.37 |
<0.001 |
PUFA n6/ PUFA n3 | 2.76±0.61 |
4.1±0.51 |
6.41±1.27 |
<0.001 |
PUFA/SFA | 0.059±0.009 | 0.056±0.002 | 0.062±0.008 | 0.703 |
Atherogenicity index |
2.49±0.37 | 2.74±0.1 | 2.39±0.17 | 0.380 |
Thrombogenic index |
2.71±0.25 |
3.09±0.18 |
2.96±0.19 |
0.019 |
Short-chain FA = C4:0-C6:0; Medium-chain FA = C8:0-C12:0; Short- + medium- chain FA = C4:0-C10:0; Long-chain FA = ≥C14:0;
Means in the same row with different superscripts are different (P<0.05).
Atherogenicity index = [(12:0 + 4(14:0) + 16:0] / [(n6+n3)PUFA + 18:1 + ΣMUFA] (Ulbricht and Southgate,
Thrombogenic index = (14:0 + 16:0 + 18:0) / [(0.5×18:1) + 0.5(ΣMUFA) + 0.5(n6PUFA) + 3(n3PUFA) + (n3PUFA/n6PUFA)] (Ulbricht and Southgate,
Nutritional recommendations are based on different ratios such as PUFA n6/ PUFA n3 and PUFA/SFA; these values are used to evaluate the nutritional value of fat for human consumption. The values for PUFA/SFA found in our cheese samples were below the recommended amount (above 0.45) for the human diet whereas only the values for sheep cheese were below the recommended level (less than 4.0) for the PUFA n6/PUFA n3 ratio (British Department of Health,
From the human health perspective, in this study, Chilean sheep cheese could be considered healthier than those imported from Europe; this is supported by the higher PUFA n3 and lower PUFA n6 contents (consequently lower PUFA n6/ PUFA n3 ratio) found in the Chilean sheep cheese (
The correlation matrix of FA discarded C4:0, C6:0, C18:0 and C20:1n9 (c11). The principal component analysis (PCA) carried out on the 16 remaining FA resulted in 4 principal components (PCs) which explained 0.84 of the overall variance in the data. PC1 and PC2 explained 0.34 and 0.28 of the variation in FA contents (
Principal component (PC) analysis related to the fatty acid profile of cheese
PC | Eigenvalue | Variables | Correlation |
---|---|---|---|
1 | 5,1 | C8:0 | 0,90 |
33,7 |
C10:0 | 0,92 | |
(33,7) |
C14:1c9 | −0,94 | |
C16:1c9 | −0,85 | ||
2 | 4,1 | C16:0 | −0,67 |
27,5 | C18:1t | 0,92 | |
(61,2) | C18:2n6(t9,12) | 0,72 | |
C18:3n3(c9,12,15) | 0,76 | ||
3 | 2,0 | C15:0 | 0,74 |
13,1 | C17:0 | 0,88 | |
(74,3) | C17:1n3(c10) | 0,91 | |
4 | 1,4 | C14:0 | 0,93 |
9,3 | C18:1n9c | −0,81 | |
(83,6) |
Proportion of variance explained;
Variance accumulated.
Three groups were found after PCA was carried out in order to obtain data clusters related to the fatty acid profiles of the cheeses. Group I was formed by 26 samples from which 23 were Chilean sheep cheeses, 2 were Chilean mixture cheeses (90% sheep and 10% cow milk) and 1 Chilean goat cheese. Group II was composed of 13 samples from which 11 were Chilean cow cheeses and 2 were Spanish mixture cheeses (proportion of milks was not found in the label). Finally, Group III was formed by 19 samples from which 9 were Spanish sheep cheeses, 2 were French sheep cheeses, 2 were Spanish mixture cheeses and 6 were Chilean goat cheeses.
PC1 consisted of the typical FA that can be found in the milk of small ruminants (C8:0 and C10:0) (Partidário
Positioning of the cheeses according to the scores obtained for PC 1 and PC 2.
Three groups were found after PCA was carried out in order to obtain data clusters related to the fatty acid profiles of the cheese. Group I: 26 samples from which 23 were Chilean sheep cheeses, 2 were Chilean mixture cheeses (90% sheep and 10% cow milk) and 1 Chilean goat cheese. Group II: 13 samples from which 11 were Chilean cow cheeses and 2 were Spanish mixture cheeses (proportion of milks was not found in the label). Group III: 19 samples from which 9 were Spanish sheep cheeses, 2 were French sheep cheeses, 2 were Spanish mixture cheeses and 6 were Chilean goat cheeses.
The different data clusters obtained in this study showed that some FA vary depending on animal species, however, there are some confounding factors related to the type of feed, production system and breed of animals (Carta
The results indicated that the FA profiles of Chilean cheese were desirable from a human health standpoint. The fatty acid profile of cheese can be used to differentiate the animal species from which the cheese is made and to some extent the geographical origin that may give some insights into animal feed and production management. The data from this study could be used to develop benchmark tools and strategies aiming at improving the nutritional characteristics of sheep cheese.
This study was supported by a research grant from FIA PYT-2008-0213 (Fondo de Innovación Agraria, Ministerio de Agricultura, Chile).