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It has been shown that several factors such as feed source and breed might influence milk fat-soluble antioxidants (AOs). This study investigated pasture feeding effects and dairy cattle breed on the content of α-tocopherol and β-carotene in cows' milk by monitoring two grazing seasons (spring and fall) as well as a summer nopasture season. Four dairy farms located in Sicily were selected: two with both Holstein and Brown Swiss cows and two with only a Modicana (M) local breed cows. Bulk milk samples of each breed per farm were collected. Milk α-tocopherol and β-carotene were highest during spring (16.2 and 9.7 μg.g −1 of fat, respectively), lowest during fall (11.2 and 0.8 μg.g −1 of fat, respectively) and intermediate during summer (13.3 and 2.5 μg.g −1 of fat, respectively). These results indicate that grazing pasture season has an important impact on milk fat-soluble antioxidant content. In particular, higher milk AO levels in spring compared to fall might be attributed to several factors such as differences in the quality and composition of pasture, differences in pasture intake and even the climate. Breed effect on milk AO contents was not so pronounced. Milk β-carotene levels did not differ significantly among breeds. Saturation of milk β-carotene may explain similar vitamin levels among breeds in spring despite different pasture intakes. It was interesting that significant levels of αtocopherol were detected in milk from M cows during summer. The latter effect could be masked by the considerably higher pasture intake of M in spring compared to the other two breeds.

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International audienceNative pasture has been shown to have a strong influence on the sensory characteristics of dairy products. However, few studies have been carried out on milk flavor profiles. The aim of the present study was to evaluate the influence of cows’ pasture-based feeding on milk volatile profile. Four Sicilian dairy farms, with three different breeds and located in the Ragusano PDO cheese production area, were selected and bulk milk samples were collected during three seasons (two pasture seasons and one non-pasture season). Pasture was available in spring and autumn time but not in summer because of the climatic conditions. A total of 72 milk samples were collected. All 72 samples were analyzed by SMart Nose®; and taking into account SMart Nose results, only 48 of spring and summer milk samples were selected for gas chromatography/olfactometry (GC/O) coupled with gas chromatography/mass spectrometry (GC/MS) systems. By applying a principal component analysis on standardized means value, results by SMart Nose showed that if native pasture was present in cows’ diet, milk samples were similar in volatile fingerprint (spring and autumn time) but it strongly differed when cows’ diet lacked native pasture (summer time). However, spring milk samples showed a higher variability than milk samples collected in autumn. Using GC/O, 179 odor-active compounds were detected in milk extracts; 87% of which were chemically identified by GC/MS. Milk samples collected in spring presented 26% more compounds than non-pasture milk samples collected in summer, thus implying a pasture effect on milk aroma profile