Relationships between the conditions of goat's milk production and the contents of some components of nutritional interest in Rocamadour cheese

Abstract

The aim of this correlational study was to (1) characterize the composition of Rocamadour goat's milk farmhouse cheese in terms of average contents and variability in fatty acids (FA), retinol, α-tocopherol, folate, β-carotene, xanthophylls, calcium, phosphorus, magnesium, potassium, zinc, sodium chloride and total antioxidant capacity (TAC) and (2) identify herd characteristics and feeding practices associated with differences of cheese composition. One hundred and twenty-six farmhouse cheeses (20 farms × 6–7 cheeses), produced in real herd management conditions throughout the year, were collected. The conditions of milk production were beforehand identified by means of surveys. The cheese composition was characterized by a high variability. The FA profile of cheese varied according to the percentage of fat from the concentrates in the herd diet, the presence of linseed in the concentrates and the herd lactation stage, and to a lesser extent the nature of the basic fodder ration, the percentage of concentrates in the herd diet, the herd milk yield and the herd breed. In outline, the cheese fat was poorer in potentially atherogenic saturated FA (C12:0 to C16:0) and richer in cis-9 C18:1 when herds were fed high percentage of fat from the concentrates, were in early lactation and have a high milk yield. It was richer in trans-11 C18:1, cis-9, trans-11 C18:2 (CLA) and C18:3 ω-3 when herds were fed low percentage of concentrates with the pasture-based rations and high percentage of fat from the concentrates and in C18:3 ω-3 when the concentrates contained linseed. The variations of xanthophyll, retinol, α-tocopherol and TAC levels in cheese were associated with the nature of the basic fodder ration, the level of vitamin supplementation for retinol and to a lesser extent the percentage of concentrates for xanthophylls and α-tocopherol. Pasture-based rations were associated with higher levels of xanthophyll, retinol, α-tocopherol and TAC in cheese than the hay-based rations, while higher percentage of concentrates in the herd diet led to lower xanthophyll and α-tocopherol contents. The vitamin supplementation of hay-based rations, unlike that of pasture-based rations, was associated with higher levels of retinol but not of α-tocopherol in cheese fat. Our results suggest that the nature of the basic fodder ration is the main influencing factor of retinol, α-tocopherol and xanthophyll contents of Rocamadour cheese, while its FA profile mainly depends on the nature of the concentrates and the lactation stage of the herd.