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Buffalo milk : a case study of some parameters related to milk production = Il latte di bufala : studio di alcuni parametri produttivi
No full textIntroduction - Over the last few years increasing attention has been paid to buffalo breeding due to the increase in the demand for buffalo mozzarella cheese. In Italy, buffaloes are reared almost exclusively for milk production and selection has led to an officially recognized breed known as Mediterranean Italian Buffalo. Aim - To contribute to knowledge of buffalo milk, the effects of parity, stage of lactation, season and year of production were investigated. Materials and methods - Daily milk yield (kg), fat (%), protein (%) and somatic cell count (CCS * 1000/ml) of 402 Italian Mediterranean buffaloes from one individual farm were evaluated from 2007 to 2011. The following factors of variability were taken into account: order of birth, stage of lactation, year and season of production. Results and discussion - The daily milk yield for the primiparous cow buffalos was 8.47 kg a head lower (P≤0.01) (-12%) than the multiparous subjects, whereas milk from individuals that had had more than eight lactations had 255.90 CCS, higher values (P≤0.01) compared to the younger subjects (+16.23%). Older animals showed also a tendency to a lower production. Milk production increased until 60 days of lactation and decreased (P≤0.01) afterwards; the peak of lactation was between the 16th and the 60th day (11.35 kg of milk a head). On the other hand, fat increased (P≤0.01) steadily from the 61st day reaching the maximum value (8.64%) at the end of lactation, while proteins showed higher values (P≤0.01) at the beginning and the end of lactation (4.84 and 4.93 respectively). The CCS was higher (P≤0.01) during the peak and the last period of lactation (241.43 and 232.39 respectively). The annual milk yield was homogeneous, with the exception of a decrease (P≤0.01) in spring (-5.4%) due to the seasonal deliveries. During 2007-2011 both milk yield and CCS increased. Conclusions - All the variables considered had effects on buffalo milk quality and yield. An increase in milk yield was linked to lower percentages of fat and proteins. In addition, the lower milk yield and the higher CCS in the older buffalos should be considered when deciding whether to keep animals in production that have had more than eight lactations
Relationship between the nutritional value of fatty acid profile and the morphometric characteristics of milk fat globules in ewe's milk
No full textOver the last few years the interest of scientists in the nutritional value of milk and dairy products has been increasing as a result of the role of specific components such as individual fatty acids (FAs) in health maintenance and chronic diseases. Milk fatty acid composition has been reported to change with the morphometric characteristics of milk fat globules. Although some studies have investigated the relationship between milk fatty acids and the morphometric characteristics of milk fat globules in cows, this relationship has not been sufficiently explored in ewe's milk.
The aim of this study was to check how the nutritional value of fatty acid profile in ewe's milk is linked to changes in the morphometric characteristics of milk fat globules (MFGs).
The study involved sampling and analyzing bulk milk from a dairy that collects and manufactures milk from six flocks of Massese ewes. All the ewes were reared in the same area of Tuscany (Italy) and were fed according to a grazing system. Milk samples were taken over a month.
Results highlighted a negative correlation between the number of milk fat globules/mL and the average diameter of the MFGs. In addition, the number of MFGs was positively related with n-3 docosapentaenoic acid, long chain FAs, monounsaturated FAs, and the n-3/n-6 ratio. It was negatively related on the other hand, with polyunsaturated fatty acids (PUFAs), n-6 FAs, thrombogenic index and the linoleic/linolenic acid ratio.
MFGs >5 μm were positively related with lauric and vaccenic acids, with short chain FAs, PUFAs, n-6 FAs, and the linoleic/linolenic ratio; whereas MFGs <2 μm were negatively related with PUFAs, n-6 and the linoleic/linolenic ratio.
In conclusion, adjusting the average diameter of MFGs could modify the nutritional value of ewe's milk and dairy products, favoring better health effects
Evaluation of the fatty acid profile from the core and membrane of fat globules in ewe's milk during lactation
Get PDFThe 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
Native milk fat globule size and its influence on the natural creaming properties of buffalo milk
Get PDFWe investigated the influence of the physical characteristics of fat globules on the creaming properties of buffalo milk and on the fatty acid profile of the various fractions separated by natural creaming. A total of six bulk buffalo milk samples were taken from one individual farm in central Italy. An aliquot of each fresh raw milk sample underwent gravity separation and three fractions were separately collected: the bottom, middle, and top. The top and medium fractions showed a significantly (p<0.01) higher average diameter of the milk fat globules and a higher percentage of large globules. The top fraction was also made up of more densely packed globules as revealed by the higher (p<0.01) number of globules per ml. The smallest globules however tended to remain in emulsion, by virtue of the greater amount of membrane per unit volume, which makes them compatible with the aqueous phase. As a result the highest percentages of small globules were found in the bottom phase. The creaming capacity of buffalo milk was lower compared to cow milk. Despite the higher contribution of lipids in the top fraction, there were more fatty acids that are considered beneficial to human health, such as C18:0 (p<0.01), C18:2 cis9,12; C18:2 cis9, t11 (rumenic acid) and C20:3 n6. In conclusion, natural creaming can act on the quality of the products by selecting globules with different diameters and nutritional quality, thus increasing the nutritional value of dairy products
Effetti della stagionatura e del metodo di conservazione sulle caratteristiche qualitative del formaggio pecorino
No full textChanges in donkey milk lipids in relation to season and lactation
Get PDFIn 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
Vitamin D content in donkey milk: preliminary results
No full textVitamin D is an essential nutrient that plays a crucial role in the calcium homeostasis and bone metabolism and also acts
as an hormone. Humans synthetize most of their vitamin D requirement from sunlight. However, an oral intake of vitamin
D may be an important source in winter, when the UVB-related synthesis is limited and for people who may not be
exposed to sunlight. However, only a few foodstuffs, mainly of animal origin, provide a considerable source of vitamin D
thus limiting the possibility of fulfilling the requirements of this vitamin. Milk contains above all vitamin D3 and D2.
Although there are several studies on the content of vitamin D in bovine milk, there is little information regarding donkey
milk. Therefore, the aims of this paper is to carry out a preliminary evaluation of the vitamin D content in donkey milk
and to investigate its seasonal modifications. Raw bulk milk samples were collected for 10 months, every 15 days, from a
dairy farm that produces donkey milk for human consumption. All the samples were analysed for chemical composition
and vitamin D content by HPLC after extraction by the partially modified Silva et al (1992) method. Donkey milk showed
a higher vitamin D content (2.31 lg/100ml ± 0.83) compared to bovine and human milk. Vitamin D in donkey milk showedseasonal variations as reported in cows. In particular, vitamin D had a higher concentration in the summer than in winter, probably due to the different sun exposure of the animals. In conclusion, donkey milk shows a considerable vitamin D content, which could be useful to meet the deficiencies of this vitamin in humans. Further investigations are necessary to
improve the vitamin D content in donkey milk through increasing its endogenous synthesis and transfer in milk and
to clarify other variability factors
Milk quality of Assaf ewes raised in central Italy (Tuscany)
Get PDFIntroduction: 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
Milk yield and quality characteristics of Cinisara and Modicana cows reared on a farm in the province of Palermo (Sicily-Italy)
Get PDFIntroduction: 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
Short communication: Monitoring nutritional quality of Amiata donkey milk: Effects of lactation and productive season
No full textMilk nutritional characteristics are especially interesting when donkey milk is aimed at consumption by children and the elderly. The aim of this study was to monitor the nutritional quality of Amiata donkey milk during lactation and productive season to provide information on the milk characteristics and to study action plans to improve milk yield and quality. Thirty-one pluriparous jennies belonging to the same farm were selected. Individual samples of milk from the morning milking were taken once per month starting from the d 30 of lactation until d 300. Milk yield and dry matter, fat, and ash content were constant throughout the experimental period. Milk total protein content showed a progressive decrease during the first 6 mo of lactation; after this period, the protein percentages remained constant (1.50%). Caseins and lactose were lower until d 60 of lactation and remained constant thereafter. During summer and autumn, milk yield and casein and lactose contents were higher, whereas during the spring season, higher protein and ash contents were found. The percentages of fat and dry matter were stable as were most of the minerals in the milk, except for calcium, which was higher in the spring. In conclusion, Amiata donkey milk was found to be relatively stable during lactation. This is an advantage in terms of the production and trade of a food product with consistent characteristics. The different milk yield and quality during the productive seasons were probably related to better adaptability of the animals to warm and temperate periods
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