Morphometric analysis of fat globules in ewe's milk and correlation with qualitative parameters

In this study the morphometric characteristics of fat globules from ewe’s milk have been correlated with the chemicaland technological parameters of the milk.Milk samples were taken from twenty-five Massese ewes, subdivided according to the parity; the animals were homogeneousfor lactation phase and diet. The morphometric analysis of fat globules (n./ml, diameter, surface area/volume),the standard chemical analysis, SCC and determination of the rheological parameters were performed on milk samplesobtained during the morning milking.The mean number of fat globules/ml was 3.09 x 109, with a mean diameter of 3.93 μm, ranging from 1.20 μm to 12.30μm. For all parities, a fat globule diameter ranging from 3.21 to 4.20 μm was found most frequently. Animals in the firstlambing order showed a significantly lower percentage (5.26%) of large globules (>5.21μm), while animals in the fifthlambing order showed a higher percentage (20.75%). The number of globules/ml was negatively correlated to milk production(P≤0.01) and curd firmness at 45 min (P≤0.05); whereas it was positively correlated to protein content, non-fatdry matter, and curd firming time (P≤0.05). Fat globule dimensions varied according to the parity of the animals andinfluenced various qualitative parameters of the milk

Cheese making aptitude and the chemical and nutritional characteristics of milk from Massese ewes

The purpose of this study was to determine the effects of season, locality and the different altitudes at which farms are located, on the physico-chemical composition, morphometric characteristics of fat globules, fatty acid composition and cheese making aptitude of milk of Massese ewe's raised in 11 flocks from two provinces of north-west Tuscany (Massa Carrara and Lucca). The winter lactation shows higher percentages of casein, lactose and not fat dry matter (P≤0.01); curd firming time (k20) is significantly lower and there is a greater curd firmness (a30) (P≤0.01); while in the summer there is a higher percentage of lipids (P≤0.01). The effect of the season significantly influences (P≤0.01) the size of the fat globules and impacted significantly on the fatty acids composition of the milk. In the hills the milk has a higher percentage of dry matter, protein, casein, fat, phosphorous and not fat dry matter (P≤0.01), whereas it has a lower percentage of lactose and calcium (P≤0.05). The Somatic Cell Count (SCC) and the Total Bacterial Count (TBC) are statistically greater on the plains (P≤0.01), while milk produced in the hills shows higher quantity of α-linolenic acid and lower saturated fatty acids (P≤0.05). In the two typical rearing areas for Massese ewes we found differences amongst dry matter, fat, phosphorous and SCC, higher (P≤0.01) in the province of Massa Carrara that also had the best rheological parameters, but we found the highest cheese yield (P≤0.05) in the province of Lucca where there are also the greatest weight loss (P≤0.01). The milks produced in the winter season and in hilly areas present the best physico-chemical and nutritional characteristics. However, we found that the technological side should be improved by diversifying cheese-making techniques in relation to the characteristics of milk. In fact, currently these techniques do not fully exploit the potential to transform those milks with the best qualitative characteristics

Effects of olive oil calcium soaps and phase of lactation on the fatty acid composition in the milk of Massese ewes

A basic diet of hay and concentrate, the latter supplemented with olive oil calcium soap (7% as fed) was given to 11 Massese ewes (group S) for a 3-month period, while a basic diet without the supplement was given to 11 control Massese ewes (group C) during the same period. Fatty acid composition of milk produced from the 5th to the 16th week post-partum was evaluated monthly. In group S, the fatty acids C6:0, C8:0, C10:0, C12:0, C14:0, C14:1, C18:3n-6 and C20:3n-3 (P<0.01) decreased significantly and C16:0, C18:1, total CLA, C20:0, C20:1, C20:2, C20:5n-3 (EPA), C23:0 (P<0.01) and C18:2 (P<0.05) increased with respect to the control group C. This trend lead to a decrease in short-chain fatty acids (P<0.05), an increase in unsaturated fatty acids (P<0.01), particularly MUFA, and an improved UFA/SFA ratio in group S (P<0.01). The lactation phase also significantly influenced fatty acid composition: the unsaturated/saturated fatty acids ratio was higher at the end of the lactation period. It can be concluded that the addition of protected olive oil fats to the diet of lactating ewes may improve fatty acid milk composition. In addition, the final phase of production positively affects milk quality relative to human health

Relationship between fat globule size and chemical and fatty acid composition of cow's milk in mid lactation

The milk in 57 Italian Fresian cows in mid lactation was analysed in order to define the relationship between some qualitative milk parameters and the size of milk fat globules. The study focused on the morphometric evaluation of milk fat globules, chemical parameteres and fatty acid composition of the milk. The results show that a prevalence of milk fat globules with a diameter < 6um is positively correlated (P<0.01) with the percentage of dry matter and lipids, whereas the greater presence of globules with a diameter >6 um was associated (P<0.01) with greater milk yield nad a higher percentage of lactose, non-fat dry matter and ash...........

Relationship between fat globule size and chemical and fatty acid composition of cow's milk in mid lactation

The milk in 57 Italian Fresian cows in mid lactation was analysed in order to define the relationship between some qualitative milk parameters and the size of milk fat globules. The study focused on the morphometric evaluation of milk fat globules, chemical parameteres and fatty acid composition of the milk. The results show that a prevalence of milk fat globules with a diameter < 6um is positively correlated (P<0.01) with the percentage of dry matter and lipids, whereas the greater presence of globules with a diameter >6 um was associated (P<0.01) with greater milk yield nad a higher percentage of lactose, non-fat dry matter and ash...........

Effects of olive oil calcium soaps and phase of lactation on the fatty acid composition in the milk of Massese ewes

A basic diet of hay and concentrate, the latter supplemented with olive oil calcium soap (7% as fed) was given to 11Massese ewes (group S) for a 3-month period, while a basic diet without the supplement was given to 11 control Masseseewes (group C) during the same period. Fatty acid composition of milk produced from the 5th to the 16th week post-partumwas evaluated monthly.In group S, the fatty acids C6:0, C8:0, C10:0, C12:0, C14:0, C14:1, C18:3n-6 and C20:3n-3 (Pand C16:0, C18:1, total CLA, C20:0, C20:1, C20:2, C20:5n-3 (EPA), C23:0 (Pincreased with respect to the control group C. This trend lead to a decrease in short-chain fatty acids (Pincrease in unsaturated fatty acids (Plactation phase also significantly influenced fatty acid composition: the unsaturated/saturated fatty acids ratio was higherat the end of the lactation period.It can be concluded that the addition of protected olive oil fats to the diet of lactating ewes may improve fatty acid milkcomposition. In addition, the final phase of production positively affects milk quality relative to human health