192 research outputs found
Evaluation of the morphometric characteristics of ewe milk fat globules, cheese yield and ripening in the intermediate lactation phase
The study was carried out on twenty ewes kept indoors at 25 days post partum. The experiment lasted 60 days, from 40 to 100 days post partum. The animals were homogeneous in terms of parity, lactation phase and feed. The results show that, as the lactation phase progresses, there is a gradual increase in the percentage of fat and a decrease in the average diameter of the fat globules. In particular, before the 55 days of lactation the milk quality and the cheese yield are lower and the weight loss at 10 days of ripening is higher
Amiata donkeys: fat globule characteristics, milk gross composition and fatty acids
Amiata donkeys are a native breed reared in central Italy. Safeguarding native donkey breeds represents an opportunity for the development of marginal areas, especially given that donkey milk is now appearing on the market due to its potential benefits for human health. To date, only a few studies have focused on the characteristics of the milk fat globules (MFGs) in the donkey species. The aim of this study was to assess the morphometric characteristics of the fat globules, gross composition and fatty acid classes in milk from Amiata donkeys reared according to the typical farming and feeding systems of the area of origin. Individual milk samples, collected from 28 Amiata donkeys between 90 and 150 days of lactation, showed the following average composition (g/100 mL): 9.47 dry matter, 1.63 protein, 0.78 casein, 0.53 fat, 7.12 lactose, and 0.36 ash. The unsaturated:saturated fatty acids ratio in milk was close to 1. The percentage of short chains was 12.29, and the percentage of long chain fatty acids was 47.64. The donkey MFGs showed an average diameter of 1.92 ÎĽm, and a number of 2.18*109/mL. Regarding MFG distribution, 70% of the globules donkey of milk are smaller than 2 ÎĽm. In conclusion, the gross composition and fatty acids of Amiata donkey milk showed similarities with milk from other Italian donkey breeds, with the exception of the monounsaturated fatty acid values which were slightly higher. Donkey MFGs had a smaller diameter and were fewer than in the ruminant species
Evaluation of the fatty acid profile from the core and membrane of fat globules in ewe's milk during lactation
The aim of this study was to investigate the differences in the fatty acid composition between the core and the membrane of the fat globules (MFGM) in sheep's milk during lactation.
Individual milk samples were collected from seven Massese ewes and analyzed for fatty acids from whole milk, from the core and from the MFGM.
The MFGM showed more saturated fatty acids (SFAs) than the core, specifically C16:0 (+21.5%) and C18:0 (+67.64%), and more polyunsaturated fatty acids (PUFAs) (+48.66%). The core had a higher content of monounsaturated (MUFAs) (+12.36%) and short chain fatty acids (SCFAs) (+640.42%).
SCFAs showed higher values (P ≤ 0.05) in milk at 60 days of lactation and lower values (P ≤ 0.05) at 30 and 120 days. These changes in the SCFAs occurred mainly in the core, whereas the amount of SCFAs in the MFGM remained almost unchanged.
The medium chain fatty acids increased with advancing lactation in the whole milk, in the core and in the MFGM; the long chain fatty acids on the other hand decreased.
In addition, the SFAs increased during lactation, while MUFAs and PUFAs tended to decrease in the decreasing lactation phase; the same trends were observed the core and in the MFGM
Milk yield and quality characteristics of Cinisara and Modicana cows reared on a farm in the province of Palermo (Sicily-Italy)
Introduction: In Italy there are a large number of indigenous breeds at high risk of extinction. These include the Modicana and Cinisara cows that are native to Sicily and are included in the “Register of native cattle breeds of limited diffusion”.
Aim: The present study investigates the variability of the main quality parameters of milk from two Sicilian cow genotypes regarding the physiological and environmental factors that affect milk production.
Materials and methods: 99 individual Modicana and 87 Cinisara milk samples were taken. The cows were different in terms of parity and lactation and were reared on pasture on the same farm in the province of Palermo at 1077 meters above sea level. Milk yield, total protein, lipids (MilkoScan, Italian Foss Electric, Padova, Italy), and somatic cell count (SCC) (n*1000/ml of milk) (Fossomatic, Italian Foss Electric, Padova, Italy) were evaluated for each individual.
Results and discussion: Higher milk yields were recorded before 60 days of lactation, in summer and autumn, when the majority of births are concentrated. Fat and protein percentages remained constant during lactation. SCC did not vary significantly and was below the maximum limit identified for bulk milk by current legislation. The Modicana and Cinisara milk was richer in fat and protein than other more specialized dairy breeds. Despite Cinisara presenting a higher somatic cell linear score (LS) than Modicana. The higher values of LS found in Cinisara than in Modicana might be due to the shape of the udder which in Cinisara has thicker and large teats which makes milking more difficult. However, the LS showed no changes either in the course of lactation, nor in terms of parity.
Conclusions: Milk yield was not high Modicana and Cinisara compared other more specialized dairy breed, however they produce more concentrated milk, higher in protein and fat. These are important characteristics since Modicana and Cinisara milk is intended for the production of typical cheeses.
In Cinisara and Modicana cows the production was affected by season. An improvement of use of pastoral resources may favour a constant milk yield and quality. The data from the study would help to preserve and improve the traits of these native breeds which are indispensable for the development of regions and marginal pastures of Sicily, and for the preservation of animal biodiversit
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
Changes in donkey milk lipids in relation to season and lactation
In this study the fatty acid profile and morphometric characteristics of fat globules in Amiata donkey milk in relation to the lactation phase and production season have been evalutated. Individual donkey milk samplings were carried out monthly starting from day 30 of lactation until day 300. The amount of fat and the diameter of the milk fat globules were fairly stable during lactation, whereas the number of globules/mL of milk decreased significantly only in the last phase of lactation. The fatty acid composition showed only a few changes during lactation, which consisted in a progressive decrease in the short chain fatty acids and an increasing trend in the monounsaturated fatty acids. Winter milk showed a significantly larger average diameter, a lower number of fat globules/mL, lower (P < 0.01) percentages of short-chain saturated fatty acids and more (P < 0.01) long-chain and monounsaturated fatty acids. In addition, significantly lower percentages of C18: 0 and higher of palmitoleic, oleic and vaccenic acids were detected in the cooler season. In conclusion the lipid fraction of donkey milk did not show notable changes during lactation
Nutritional and nutraceutical quality of donkey milk
In the last few decades, there has been a renewed interest in donkeys by the scientific community involved in the recovery of biodiversity, in the rescue of some donkey breeds that have become almost extinct, and in the rediscovery of donkey milk. In addition, due to the increase in food allergies, attention has been focused on the need for a “natural” milk with a good taste, which could be used in some childhood illnesses such as allergy to cow's milk proteins allergy (CMPA). Donkey milk is very similar to human milk, especially in terms of its protein profile and lactose content, which increases palatability, stimulates intestinal absorption of calcium, and thus provides an excellent substrate for the development of enteric flora. The high content of lysozyme in this milk favours selective action against pathogenic microorganisms. In addition, the mineral content (such as calcium) and liposoluble vitamins make it an excellent nutraceutical product. A project aimed to create a donkey milk supply chain from the Amiata native breed has recently been developed in Central Italy (Tuscany). In this paper, the nutritional and nutraceutical characteristics of donkey milk are reviewed in detail. In addition, some of the potential uses of donkey milk have been briefly described: in the diet of children with CMPA, in the diets of the elderly and of people who need to lose weight by virtue of the low fat content and the good contribution of omega 3
Milk quality of Assaf ewes raised in central Italy (Tuscany)
Introduction: The demand from outside Italy for Italian cheeses made from sheep milk has recently increased. Due to the agricultural productivity crisis, thousands of dairy farms have closed down. In the farms that have remained, there has been a tendency to increase the average milk production. Thus, in Italy there has been a recent increase in the importation of foreign high-yielding sheep breeds. Aim: this study focuses on the Assaf breed imported from Spain, which is being used to replace traditional breeds. The milk yield and quality from the Assaf sheep were monitored during lactation. Materials and methods: Ten pluriparous Assaf ewes underwent milk sampling. Milk quality, fatty acid composition and coagulation properties were analysed from day 20 to day 170 of lactation. Results and discussion: The Assaf sheep showed a high production capacity (about 1.3+0.50 litres / day, on the average) but lower percentage of fat and protein than Assaf reared in other Mediterranean Countries and than local breeds. The coagulation properties (k20 and a30) were better at the end of lactation (k20=1.37 min, a30=36.51 mm). In this phase, the increase in saturated fatty acids and medium chain fatty acids, the decrease in monounsaturated, and saturated: unsaturated fatty acid ratio, indicated a poorer milk nutritional quality in this period. Conclusions: We confirmed the high productivity of the Assaf sheep. The nutritional quality of its milk fat seems better at the beginning of lactation when less saturated, and more monounsaturated fatty acids are present in the milk. Furthermore, higher protein and better coagulation properties of the milk were observed at the end of lactatio
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