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The yield, flavor, and texture of ripened cheese result from numerous interrelated microbiological, biochemical, and physical reactions that take place during ripening. The aims of the present study were to propose a 2-compartment first-order kinetic model of cheese weight loss over the ripening period; to test the variation in new informative phenotypes describing this process; and to assess the effects on these traits of dairy farming system, individual farms within dairy system, animal factors, and milk composition. A total of 1,211 model cheeses were produced in the laboratory using individual 1.5-L milk samples from Brown Swiss cows reared on 83 farms located in Trento Province. During ripening (60 d; temperature 15°C, relative humidity 85%), the weight of all model cheeses was measured, and cheese yield (cheese weight/processed milk weight, %CY) was calculated at 7 intervals from cheese-making (0, 1, 7, 14, 28, 42, and 60 d). Using these measures, a 2-compartment first-order kinetic model (3-parameter equation) was developed for modeling %CY during the ripening period, as follows: [Formula: see text] , where %CYt is the %CY at ripening time t; %CYi and %CYf are the modeled %CY traits at time 0 d (%CYi = initial %CY) and at the end of a ripening period sufficient to reach a constant wheel weight (%CYf = final %CY after 60 d ripening in the case of small model cheeses); kCY is the instant rate constant for cheese weight loss (%/d). Cheese weight and protein and fat losses were calculated as the % difference between the model cheeses at 0 and after 60 d of ripening. The variation in cheese pH was calculated as the % difference between pH at 0 and after 60 d. Dairy system, individual herd within dairy system, and the cow's parity and lactation stage (tested with a linear mixed model) strongly affected almost all the traits collected during model cheese ripening. Milk fat, protein, lactose, pH, and somatic cell score also greatly affected almost all the traits, although kCY was affected only by milk protein. After including milk composition in the linear mixed model, the importance of all the herd and animal sources of variation was greatly reduced for all traits. The proposed model and novel traits could be tested, first, with the aim of establishing new monitoring procedures enabling the dairy industry to improve milk quality-based payment systems at the herd level and, second, with a view to exploring possible genetic improvements to dairy cow populations.

Parmigiano Reggiano is a hard PDO cheese made from bovine raw milk, whose microbiological characteristics have important repercussions on cheese quality. According to the EU official production protocol, milk temperature at the farm must not drop below 18 °C. The present research aimed to study the effect of cooling milk at the farm at 9 °C on the characteristics of milk and on the cheesemaking process and losses during manufacture. Six cheesemaking trials were performed in two different dairies. In each of them, two cheesemakings were made in parallel: one with milk kept at 9 °C (TM9) and the other with milk kept at 20 °C (TM20). TM9 milk, in comparison with TM20, showed after the creaming process a significant reduction not only of total bacterial count but also of psychrotrophic and lipolytic bacteria. At the same time, TM9 milk showed a higher creaming capacity and, consequently, a lower fat content than TM20. TM9 vat milk had worst coagulation properties than TM20, which caused slightly higher loss of fat and curd fines into the whey. Nevertheless, these changes were too small to influence the efficiency of the cheesemaking process, conversely, maintaining milk at the farm at 9 °C led to a reduction of the number of spoilage bacteria.

Milk lactose, pH, somatic cell count (SCC), bacterial count and NaCl are indirect markers of the mammary gland status; they can be used to screen milk quality and its technological properties. The variability of milk composition and coagulation properties from 1272 individual goat milk samples as a function of the udder health indicators was investigated. High lactose concentrations were associated with reduced coagulation time, but weakened curd firmness traits. High pH values impaired coagulation, while high SCC had delayed coagulation time but reduced curd-firming rate. Samples with high bacterial count were characterised by softer curds, but had faster curd-firming and larger syneresis rates. High concentrations of NaCl were associated with reduced fat, protein, and casein content, and impaired coagulation traits. These results show that the concurrent analysis of these markers can be highly informative and suitable to monitor the quality of milk destined for cheese-making.

Simple Summary Parmigiano Reggiano is a Protected Designation of Origin (PDO) hard-cooked cheese made from raw milk that is ripened from 18 to over 24 months. Since the EU official protocol does not allow farmers to store the milk at the farm at a temperature lower than 18 °C, the conditions applied during storage strongly affect milk quality and suitability to cheese-making. At this temperature, the bacterial growth and the activity of proteolytic enzymes, responsible for milk alteration, cannot be inhibited. The aim of this research was to study the effect of storing milk at 9 °C, at the farm, on the chemical characteristics, proteolysis and organic acid profile of Parmigiano Reggiano cheese during ripening. The obtained results revealed lower fat and higher protein contents with respect to the cheese produced with milk stored at 20 °C. Regarding proteolysis, peptone nitrogen was the only parameter that significantly increased in the cheese produced with the milk stored at 9 °C. Despite of the statistical significance of the differences observed, they appeared as too small for changing the overall “typicality” of the cheese, and should be included within the ordinary range of variability of Parmigiano Reggiano. Abstract Parmigiano Reggiano is a Protected Designation of Origin (PDO) cheese whose official production protocol provides that milk cannot be stored at less than 18 °C at the farm. The possibility of refrigerating milk at the farm is highly debated, since it should allow for the limiting of bacterial growth, thus improving the quality of the cheese. The present research aimed to study the influence of storing the milk at 9 °C on the chemical composition and proteolysis during the ripening of Parmigiano Reggiano cheese. The experimentation considered six cheese-making trials, in which both evening and morning milks were subdivided into two parts that were maintained at 9 and 20 °C. After Parmigiano Reggiano cheese-making, one of the twin wheels obtained was analyzed after 21 months of ripening. From each cheese, two different samples were taken, one from the inner zone, and the other from the outer zone. The results of the chemical analyses evidenced that milk storage at 9 °C significantly (p ≤ 0.05) influenced fat, crude protein, soluble nitrogen and peptone nitrogen contents. Nevertheless, the differences observed with respect to the cheese obtained with milk stored under standard condition were very small and should be considered within the “normal variations” of Parmigiano Reggiano chemical characteristics.

Natural variations in milk minerals, their relationships, and their associations with the coagulation process and cheese-making traits present an opportunity for the differentiation of milk destined for high-quality natural products, such as traditional specialties or Protected Designation of Origin (PDO) cheeses. The aim of this study was to quantify the effects of the native contents of Ca, P, Na, K, and Mg on 18 traits describing traditional milk coagulation properties (MCP), curd firming over time (CFt) equation parameters, cheese yield (CY) measures, and nutrient recoveries in the curd (REC) using models that either included or omitted the simultaneous effects of milk fat and casein contents. The results showed that, by including milk fat and casein and the minerals in the statistical model, we were able to determine the specific effects of each mineral on coagulation and cheese-making efficiency. In general, about two-thirds of the apparent effects of the minerals on MCP and the CFt equation parameters are actually mediated by their association with milk composition, especially casein content, whereas only one-third of the effects are direct and independent of milk composition. In the case of cheese-making traits, the effects of the minerals were mediated only negligibly by their association with milk composition. High Ca content had a positive effect on the coagulation pattern and cheese-making traits, favoring water retention in the curd in particular. Phosphorus positively affected the cheese-making traits in that it was associated with an increase in CY in terms of curd solids, and in all the nutrient recovery traits. However, a very high P content in milk was associated with lower fat recovery in the curd. The variation in the Na content in milk only mildly affected coagulation, whereas with regard to cheese-making, protein recovery was negatively associated with high concentrations of this mineral. Potassium seemed not to be actively involved in coagulation and the cheese-making process. Magnesium content tended to slow coagulation and reduce CY measures. Further studies on the relationships of minerals with casein and protein fractions could deepen our knowledge of the role of all minerals in coagulation and the cheese-making process.

Recent available instruments allow to record the number of differential somatic cell count (DSCC), representing the combined proportion of polymorphonuclear leukocytes and lymphocytes, on a large number of milk samples. Milk DSCC provides indirect information on the udder health status of dairy cows. However, literature is limited regarding the effect of DSCC on milk composition at the individual cow level, as well as its relation to the somatic cell score (SCS). Hence, the aims of this study were to (i) investigate the effect of different levels of DSCC on milk composition (fat, protein, casein, casein index, and lactose) and (ii) explore the combined effect of DSCC and SCS on these traits. Statistical models included the fixed effects of days in milk, parity, SCS, DSCC and the interaction between SCS &times, DSCC, and the random effects of herd, animal within parity, and repeated measurements within cow. Results evidenced a decrease of milk fat and an increase in milk fatty acids at increasing DSCC levels, while protein, casein and their proportion showed their lowest values at the highest DSCC. A positive association was found between DSCC and lactose. The interaction between SCS and DSCC was important for lactose and casein index, as they varied differently upon high and low SCS and according to DSCC levels.

An important problem in mountain areas is the abandonment of pasture. This trend can be combated by the valorisation of typical dairy products, such as &ldquo, Formaggella della Valle di Scalve&rdquo, a semi-cooked traditional cheese made from whole milk in a mountain area in Italy. The aim of the present research was to compare the fatty acid (FA) profile and the sensory properties of this cheese as manufactured under different conditions: i) from the milk of cows grazing on mountain or valley pasture or fed indoors, ii) from the milk of cows fed hay or fed silage. In the first case, five cheesemaking trials were conducted during two years for each of the following situations: mountain pasture (A), pasture at the bottom of the valley (P) (about 1000m asl), stall (S). In the second case, three cheesemaking trials were conducted for each of the following situations: cows fed silage (I), cows fed hay (F). S cheese was richer in medium-chain FAs, while long-chain FAs were higher in P and A cheeses. On the other hand, long chain fatty acids (LCFA) were more abundant in P and A cheeses than in S. In general, MUFA, PUFA and, consequently, total unsaturated FA (UFA), were significantly higher in the P and A cheeses than S (UFA: 36.55 and 38.34, respectively, vs 31.13, p &lt, 0.001), while SFA showed higher values in S (68.85 vs 63.41 and 61.68 in P and A, respectively, 0.001). Conjugated linoleic acid isomers (CLA) were more represented in the P and A samples (1.86 in P and 1.52 in A, vs 0.80 in S, 0.001), Omega 3 fatty acids, and in particular &alpha, linolenic acid, were more abundant in P than in S cheese. In winter, the I sample (silage) presented higher percentages of myristic (C14), myristoleic (C14:1) and omega 6 acids, whereas F cheese (hay) contained higher concentrations of CLA. The triangular test of sensory analysis showed that, in general, F cheeses were judged as &ldquo, sweeter&rdquo, than I, with aromatic profiles characterized by higher content of 2- butanol and ethyl capronate.

Little is known about the complex process of cheesemaking at the individual level of dairy goats because of the difficulties of producing a high number of model cheeses. The objectives of this work were (1) to study the cheesemaking ability of goat milk; (2) to investigate the variability of cheesemaking-related traits among different farms; (3) to assess the effects of stage of lactation and parity; and (4) to compare 6 breeds of goat (Saanen and Camosciata delle Alpi for the Alpine type; Murciano-Granadina, Maltese, Sarda and Sarda Primitiva for the Mediterranean type) for their cheesemaking ability. For each goat (n = 560) we studied (1) 8 milk quality traits (fat, protein, total solids, casein, lactose, pH, somatic cell score, and bacterial count); (2) 4 milk nutrient recovery traits (fat, protein, total solids, and energy) in curd; (3) 3 actual cheese yield traits (fresh cheese, cheese solids, and cheese water); (4) 2 theoretical cheese yield values (fresh cheese and cheese solids) and the related cheesemaking efficiencies; and (5) daily milk yield and 3 daily cheese yield traits (fresh cheese, cheese solids, and water retained in the curd). With respect to individual animal factors, farm was not particularly important for recovery traits or actual and theoretical cheese yield and estimates of efficiency, whereas it highly influenced daily productions. Parity of goats influenced daily cheese production, whereas DIM slightly affected recovery as well as percent and daily cheese yield traits. Breed was the most important source of variation for almost all cheesemaking traits. Compared with those of Alpine type, the 4 Mediterranean breeds had, on average, lower daily milk and cheese productions, greater actual and theoretical cheese yield, and higher recovery of nutrients in the curd. Among Alpine type, Camosciata delle Alpi was characterized by greater nutrients recovery than Saanen. Within the 4 Mediterranean types, the 3 Italians produced much less milk per day, with much more fat and protein and greater recovery traits than the Murciano-Granadina, resulting in greater actual cheese yield. Within the Italian breeds, milk from Sarda and Sarda Primitiva was characterized by lower daily yields, higher protein and fat content, and greater recoveries of nutrients than Maltese goats. These results confirmed the potential of goat milk for cheese production and could be useful to give new possibilities and direction in breeding programs.

This Research Communication investigated the potential of mid-infrared spectroscopy to predict detailed mineral composition of bovine milk. A total of 153 bulk milk samples were analysed for contents of Ca, Cl, Cu, Fe, K, Mg, Na, P and Zn. Also, soluble and colloidal fractions of Ca, Mg and P were quantified. For each milk sample the mid-infrared spectrum was captured and stored. Prediction models were developed using partial least squares regression and the accuracy of prediction was evaluated using both cross- and external validation. The proportion of variance explained by the prediction models in cross-validation ranged from 34% (Na) to 77% (total P), and it ranged from 13% (soluble Mg) to 54% (Cl−) in external validation. The ratio of the standard deviation of each trait to the standard error of prediction in external validation, which is an indicator of the practical utility of the prediction model, was low and never greater than 2. Results from the current study supported the limited usefulness of mid-infrared spectroscopy to predict minerals present in low concentration in bulk milk. For major mineral components, results from the present research did not match previous findings demonstrating the need for further studies using larger reference datasets.

Ca, P and Mg content and distribution between soluble and colloidal phases of donkey milk (DM) were investigated in 62 individual milk samples collected from 9 Ragusano donkeys followed from the second to the ninth month of lactation. Ca (69%) and P (64%) were mainly associated with casein, while Mg was largely found in the soluble form (69%). Only 25% of the colloidal P was present as phosphorylated residues of caseins (casein-P). The colloidal contents of Ca, casein-P, inorganic P (as a constituent of the colloidal calcium phosphate; CCP) and Mg were 1.84, 1.30, 0.45 and 0.15 mmol g casein −1 , respectively, revealing a high level of mineralisation of DM casein micelle. The colloidal Ca to colloidal inorganic-P ratio was 1.51, suggesting that most colloidal Ca was in the form of CCP. All parameters were affected by the period of lactation, except casein level in milk and its level of phosphorylation.

Donkey milk is increasingly being proposed as a natural alternative milk for various categories of consumers, especially infants and the elderly population. However, its potential production, gross, and mineral composition have not been deeply investigated yet. Sixty-two individual milk samples were collected monthly from nine Ragusano donkeys reared in a specialized dairy farm. Milk yield as well as chemical and mineral composition, including macro and micro elements, were investigated over an entire lactation, from the second to the ninth month of milking. Milk yield averaged 1.64 kg/day, which highlights good aptitude of the Ragusano breed for the production of milk. Gross composition was characterized by low content of dry matter (8.19%), a high amount of lactose (6.07%), low protein (1.34%), and very low-fat content (0.16%). Whey proteins represented 58% of the total protein, and proteose-peptones accounted for 0.35 &plusmn, 0.07 g per 100 g. Total ash content was 0.36 g per 100 g and represented 4.40% of the dry matter. The most abundant element was K, which was followed by Ca, Na, and P. As expected, the micro elements Fe, Zn, and Cu were found in low amounts or in traces. Dry matter, fat, whey proteins. The total ash, Ca, P, Mg, and mineral ratios were significantly affected by the lactation stage.

The assessment of the efficiency of the cheese-making process (ECMP) is crucial for the profitability of cheese-factories. A simple way to estimate the ECMP is the measure of the estimated cheese-making losses (ECL), expressed by the ratio between the concentration of each constituent in the residual whey and in the processed milk. The aim of this research was to evaluate the influence of the season and cheese factory on the efficiency of the cheese-making process in Parmigiano Reggiano cheese manufacture. The study followed the production of 288 Parmigiano Reggiano cheese on 12 batches in three commercial cheese factories. For each batch, samples of the processed milk and whey were collected. Protein, casein, and fat ECL resulted in an average of 27.01%, 0.72%, and 16.93%, respectively. Both milk crude protein and casein contents were negatively correlated with protein ECL, r = &minus, 0.141 (p &le, 0.05), and r = &minus, 0.223 (p &le, 0.001), respectively. The same parameters resulted in a negative correlation with casein ECL (p &le, 0.001) (r = &minus, 0.227 and &minus, 0.212, respectively). Moreover, fat ECL was correlated with worse milk coagulation properties and negatively correlated with casein content (r = &minus, 0.120, p &le, 0.05). In conclusion, ECLs depend on both milk characteristics and season.

This study examined the milk quality of the autochthonous cattle breed Modenese (MO) in comparison with Italian Friesian (IF), at peak and mid lactation, with the aim to support the interest in sustainability of the local cattle breeds in Europe. Forty-eight individual milk samples were collected from 11 MO and 14 IF pluriparous cows, housed in a free stall barn under similar conditions of feeding and management, at 8 and 21 weeks post-calving; daily milk yield (MY) and body condition score (BCS) were individually recorded. Breed differences were observed, being MY lower in MO cows, but BCS, titratable acidity, freezing point, casein (MC), total calcium (Ca), total phosphorus (P) and colloidal P contents were higher compared to IF cows. Time affected BCS, MY, milk protein (MP), MC, urea, casein P and the micellar content of colloidal Ca and colloidal inorganic P. A factorial analysis was performed and four common factors were obtained with a cumulative explained variance of 77.7% of the total original. MO milk showed a nutritionally interesting mineral profile and processing properties suitable for the production of typical cheese that could be interesting for improving the interest in the conservation of animal genetic resources.

In dairy goats, very little is known about the effect of the 2 most important indirect indicators of udder health [somatic cell count (SCC) and total bacterial count (TBC)] on milk composition and cheese yield, and no information is available regarding the effects of lactose levels, pH, and NaCl content on the recovery of nutrients in the curd, cheese yield traits, and daily cheese yields. Because large differences exist among dairy species, conclusions from the most studied species (i.e., bovine) cannot be drawn for all types of dairy-producing animals. The aims of this study were to quantify, using milk samples from 560 dairy goats, the contemporary effects of a pool of udder health indirect indicators (lactose level, pH, SCC, TBC, and NaCl content) on the recovery of nutrients in the curd (%REC), cheese yield (%CY), and daily cheese yields (dCY). Cheese-making traits were analyzed using a mixed model, with parity, days in milk (DIM), lactose level, pH, SCC, TBC, and NaCl content as fixed effects, and farm, breed, glass tube, and animal as random effects. Results indicated that high levels of milk lactose were associated with reduced total solids recovery in the curd and lower cheese yields, because of the lower milk fat and protein contents in samples rich in lactose. Higher pH correlated with higher recovery of nutrients in the curd and higher cheese yield traits. These results may be explained by the positive correlation between pH and milk fat, protein, and casein in goat milk. High SCC were associated with higher recovery of solids and energy in the curd but lower recovery of protein. The higher cheese yield obtained from milk with high SCC was due to both increased recovery of lactose in the curd and water retention. Bacterial count proved to be the least important factor affecting cheese-making traits, but it decreased daily cheese yields, suggesting that, even if below the legal limits, TBC should be considered in order to monitor flock management and avoid economic losses. The effect of NaCl content on milk composition was linked with lower recovery of all nutrients in the curd during cheese-making. In addition, high milk NaCl content led to reductions in fresh cheese yield and cheese solids. The indirect indicators of the present study significantly affected the cheese-making process. Such information should be considered, to adjust the milk-to-cheese economic value and the milk payment system.

Lactococcus lactis subsp. lactis 68, Streptococcus thermophilus 93 and Lactobacillus rhamnosus BT68, previously isolated from Traditional Mountain (TM) cheese, were tested for the production of four experimental mountain cheeses, with the aim to assess their effectiveness in leading the TM-cheese-making process. Lactococcus lactis subsp. lactis 68 and Streptococcus thermophilus 93 were used as starter cultures, whereas Lactobacillus rhamnosus BT68 was used as non-starter culture. Three control (CTRL) cheeses were manufactured without adding any starter, according to the traditional cheese-making process; nine, cheeses were produced inoculating the vat milk with the starters (ST), starter and low concentration of non-starter culture (STLC), starter and high concentration of non-starter culture (STHC). Samples of vat milk, cheese after 24 h and 7 months ripening were processed for microbiological counts. Mesophilic cocci were dominant in all 24 h-cheese samples, while a dominance of both cocci and lactobacilli was observed after 7 months ripening. The total genomic DNA was extracted, and a fragment of V1-V3 region was amplified and pyrosequenced. Lactococci and streptococci were the most abundant species, and Lc. lactis ssp. lactis 68 affected the proliferation of milk-resident Lc. lactis ssp. cremoris, during the early fermentation. Lb. rhamnosus BT68 showed to be responsible in reducing the abundance of other Lactobacillus species. Moreover, it likely competed against Sc. thermophilus 93 for the same energetic sources, when added in concentration higher than 5 × 103 CFU/mL milk. The sensorial and fatty acid (FA) composition analysis were performed on cheese samples at the end of ripening, demonstrating that the inoculated cheeses had better sensorial characteristics (aspect, smell, taste, texture) than CTRL cheeses, and that Lb. rhamnosus BT68 at high concentration is related to the increase of short chain fatty acids and conjugated linoleic acid in cheese after 7 months ripening.

The mammary gland inflammation process is responsible for an increased number of somatic cells in milk, and transfers into the milk of some blood components, this causes alterations in the chemical composition and physico-chemical properties of milk. For this reason, somatic cell count (SCC) is one of the most important parameters of milk quality, therefore, European Union (EU) Regulation no 853/2004 has stated that it must not exceed the limit value of 400,000 cells/mL. The research aimed to compare chemical composition, cheese yield, and cheesemaking losses of two groups of vat milks used for Parmigiano Reggiano production, characterized by different SCC levels. During two years, ten cheesemaking trials were performed in ten different cheese factories. In each trial, two cheesemaking processes were conducted in parallel: one with low SCC milk (below 400,000 cells/mL, Low Cell Count (LCC)) and the other with high SCC milk (400,000&ndash, 1,000,000 cells/mL, High Cell Count (HCC)). For each trial, vat milk and cooked whey were analyzed, after 24 months of ripening, cheeses were weighed to calculate cheese yield. The HCC group had lower casein content (2.43 vs. 2.57 g/100 g, p &le, 0.05) and number (77.03% vs. 77.80%, 0.05), lower phosphorus (88.37 vs. 92.46 mg/100g, 0.05) and titratable acidity (3.16 vs. 3.34 &deg, SH/50 mL, 0.05) compared to LCC. However, chloride (111.88 vs. 104.12 mg/100 g, 0.05) and pH (6.77 vs. 6.71, 0.05) were higher. Fat losses during cheesemaking were higher (20.16 vs. 16.13%). After 24 months of ripening, cheese yield was 8.79% lower for HCC milk than LCC (6.74 vs. 7.39 kg/100 kg, 0.05).

The characterization of milk from red deer (Cervus elaphus, ReD), fallow deer (Dama dama, FaD) and roe deer (Capreolus capreolus, RoD) was carried out in this study, focusing on mineral contents and their distribution between the soluble and colloidal phases of milk. Individual milk samples were collected from 23 ReD hinds, 31 FaD does, and 5 RoD does. The concentrations (mg/100 g) of minerals in milk were as follows (mean±SD): Ca, ReD = 273 ± 33, FaD = 234 ± 46, RoD = 418±101; P, ReD = 191 ± 15, FaD = 158 ± 16, RoD = 316 ± 46; Mg, ReD = 18 ± 2, FaD = 29 ± 7, RoD = 24 ± 2; Na, ReD = 41 ± 7, FaD = 41 ± 8, RoD = 45 ± 3; K, ReD = 126 ± 6, FaD = 120 ± 17, RoD = 140 ± 16. The % of minerals in the soluble phase of milk were as follows (mean ± SD): Ca, ReD = 27 ± 6, FaD = 27 ± 3, RoD = 22 ± 3; P, ReD = 30 ± 6, FaD = 28 ± 6, RoD = 30 ± 1; Mg, ReD = 57 ± 10, FaD = 55 ± 9, RoD = 51 ± 15. At micellar level, the contents of Ca, P and Mg (mmol/100 g casein) resulted as follow: Ca, ReD = 0.79 ± 0.12, FaD = 0.68 ± 0.16, RoD = 0.96 ± 0.15; P, ReD = 0.65 ± 0.10, FaD = 0.54 ± 0.09, RoD = 0.83 ± 0.08; Mg, ReD = 0.05 ± 0.01, FaD = 0.08 ± 0.01, RoD = 0.06 ± 0.02.

The aim of this study was to determine the influence of the somatic cell content (SCC) of milk on Parmigiano-Reggiano cheese yield, produced in commercial cheese factories under field conditions. The study was carried out following the production of 56 batches of Parmigiano-Reggiano in 13 commercial cheese factories by processing milk collected from Italian Friesian cattle herds. The vat-milk (V-milk) used for making each cheese batch was obtained by mixing evening milk (partially skimmed following spontaneous separation of fat overnight, natural creaming) and morning milk. The batches of cheese produced were divided into 5 classes according to the SCC value of the evening milk determined prior to natural creaming (class 1, from 0 to 200 000; 2, 201 000–300 000; 3, 301 000–400 000; 4, 401 000–500 000; 5, over 501 000 cells/ml). The cheese yield was calculated as the amount of 24-h cheese, expressed in kilograms, obtained from 100 kg of V-milk (24 h ACY). The values of fat, crude protein, true protein, casein and 24 h ACY of V-milk were negatively correlated with the somatic cell score (SCS) of the evening milk. Conversely, a positive correlation was observed between chloride and SCS. Fat, protein fractions (crude protein, casein and whey proteins), P and titratable acidity of V-milk were positively correlated with its 24 h ACY, while chloride, pH and SCS showed a negative correlation. A significant drop in 24 h ACY was observed in classes 3, 4 and 5, therefore when the SCC of the evening milk exceeded 300 000 cells/ml. Finally a lower recovery of milk fat in cheese was observed as SCC of evening milk increase.

Talijanski tvrdi kuhani sirevi, kao što su Parmigiano Reggiano i Grana Padano, imaju veliku nutritivnu vrijednost. Prema definiciji Europske Unije smatraju se funkcionalnom hranom, jer sadržavaju spojeve koji imaju specifična biološka svojstva. U ovom su preglednom radu ukratko opisani ti spojevi te njihov pozitivan učinak na zdravlje, i to u nekoliko poglavlja: proteini i peptidi, masti i lipidi, ugljikohidrati i prebiotici, probiotičke bakterije, vitamini, mineralne tvari, te sastojci mliječnih proizvoda s aktivnom ulogom u prevenciji bolesti. U uzorcima sira Parmigiano Reggiano pronađeno je nekoliko peptida s dokazanim biološkim svojstvima, npr. fosfopeptidi, koji imaju sposobnost vezivanja mineralnih tvari i funkciju prijenosnika funkcionalnih skupina, peptidi s imunomodulacijskim učinkom, te peptidi s antihipertenzijskim svojstvima i sposobnošću inibicije enzima koji konvertira angiotenzin. Među lipidima su opisane uloge konjugirane linolne kiseline i drugih masnih kiselina u siru. Također su opisani oligosaharidi s prebiotičkim svojstvima i probiotičke bakterije. Na kraju je posebno naglašena iskoristivost kalcija iz sireva, što je bitno za zdravlje kostiju., Italian hard cooked types of cheese, like Parmigiano Reggiano and Grana Padano, are characterised by positive nutritional qualities. In fact, they contain substances that have particular biological activities, and therefore they can be fully considered, according to the definition given by the European Unit, as ‘functional’ foods. This short review concisely describes these components and the beneficial effects related to their activities. The description of the biologically active components has been organised in the following paragraphs: protein and peptides, fat and lipids, carbohydrates and prebiotics, probiotic bacteria, vitamins, mineral salts, and components of dairy products active in disease prevention. In particular, several known bioactive peptides were found in Parmigiano Reggiano cheese samples: for example, phosphopeptides, which are known for their mineral-binding capacity and vehiculation activity, peptides with immunomodulatory activity, and angiotensin-converting enzyme-inhibitory peptides with anti-hypertensive effects. Among lipids, the role of conjugated linoleic acid and other fatty acids present in these cheese types was taken into consideration. The presence of oligosaccharides with prebiotic properties and probiotic bacteria was also described. Finally, particular emphasis was given to highly available calcium and its impact on bone health.

The main requirement for milk processed in most cheese typologies is its rennet coagulation ability. Despite the increasing number of studies, the causes for abnormal coagulation of milk are not fully understood. The aim of this study was to ascertain relationships between milk characteristics and its rennet coagulation ability, focusing on the influence of calcium (Ca) and phosphorus (P). Ca and P are essential constituents of the micelles. Micellar P can be present as part of colloidal calcium phosphate (inorganic-P) or covalently bound to caseins as phosphate groups (casein-P). Eighty one herd milk samples (SCC

The achievement of a sufficient acidity level by starters at early stages of manufacture is essential for a good quality Parmigiano Reggiano (PR) cheese. In this work, the chemical parameters and microbial characteristics of 18 PR cheeses during the moulding phase were analysed to determine how the microbial growth takes place conditioning acidification performances. Based on the mean values of lactic acid content, two groups of cheeses were observed. High numbers of culturable thermophilic bacteria and in particular Lactobacillus helveticus able to metabolise galactose but also grow faster in the cheese appeared to be essential conditions to achieve adequate lactic acid content. On the other hand, low acidification and residual galactose, as observed in the second group, may be associated with a lower amount of metabolically active L. helveticus and higher relevance of Streptococcus thermophilus contents in the cheese. While culturable thermophilic bacteria were fundamental for higher lactic acid production, non-culturable cells did not seem to contribute to the acidification.

The aim of this study was to evaluate the effects of different storage conditions (12, 24, 36 and 48 h at 4–6 °C and 8–10 °C and 12 and 24 h at 13–15 °C) on chemical and physico-chemical characteristics, microbial growth and processing properties of raw bulk milk. Regardless of the temperature, cold storage of milk increased the content both of calcium and phosphorus in the resulting rennet-induced curd. Storage of milk at 4–6 or 8–10 °C resulted in a significant impairment of the rennet coagulation properties after 12 h of storage, particularly at 4–6 °C. A significant decrease in the creaming capacity of milk was observed in all storage conditions, particularly for milk stored at 13–15 °C. On the basis of these observations, storage on farms at a temperature of 8–10 °C, for a period not longer than 24 h, is recommended.

Aim of this work was to investigate nursing mares milk characteristics at the end of lactation (D) and to make a comparisonwith milk taken during early lactation (3 to 30 d post partum) (E). The survey was carried out on 17 Italian Saddlemares (IS) (193 days in milk; 147 pregnancy days) and on 12 Haflinger mares (H) (174 days in milk; 146 pregnancydays). N fractions were determined by means of Kjeldahl; fat and lactose by means of mid infrared lectures; mineral elementswere determined by Atomic Absorption Spectrophotometry; P by colorimetry. Data referring to 58 individual milksamples were analyzed by ANCOVA. Significant variations, similar in both breeds, were observed (E vs D) for density at15°C (1.036 vs 1.034), pH (6.94 vs 7.24), titratable acidity (3.56 vs 1.70 °SH), fat (1.17 vs 0.76% g/100g of milk),crude protein (2.31 vs 1.68% g/100g), casein number (52.37 vs 46.59) and ash (0.50 vs 0.30% g/100g); similarly(mg/100g) for non casein N (172.31 vs 142.05), non protein N (34.43 vs 29.09), P (61.30 vs 32.48), Ca (112.88 vs54.42), Mg (8.40 vs 4.38) and K (60.77 vs 41.31). Freezing point, lactose and Na showed no significant variations. Atthe end of lactation, milk resulted poorer in all main organic components, except lactose, and in all mineral components,except Na. Only freezing point and phosphorus variations differed in IS from H. Breed significantly affected fat, casein Nand ash mean contents.

From each of twenty wheels of Parmigiano–Reggiano cheese of different ages (1–24 months), samples representative of the inner part (I, 10 cm from the round side and 7 cm from the flat side) and of the outer part (O, the rest of the cheese after removing the rind) were collected. For each sample, free fatty acids (FFAs, expressed as mg kg−1 cheese fat) were determined by quantitative capillary gas chromatography. In 18- and 24-month-old cheese, total levels of FFAs (as sum of individual FFAs) were significantly (P ≤ 0.05) higher in O than I, whereas no differences between regions were observed in 1-, 6- and 12-month-old cheeses. In terms of short (C4–C8) and medium (C10–C14) chain FFAs, levels in the outer regions were higher (P ≤ 0.05) than inner regions for cheeses from 6- to 24-month-old. The content of long-chain FFAs (C16–C18:2) was higher in O than I in 18- and 24-month-old cheeses.

The aim of this research was to describe the changes of the nitrogen fractions in milk of Haflinger nursing mares and in particular to determine the whey protein content and distribution, and their evolution throughout the first 6 mo of lactation. Samples were collected by hand-milking on days 4, 20, 40, 60, 80, 120, 150 and 180 post-partum. Nitrogen fractions were determined by Kjeldahl on 80 samples from 10 mares, while HPLC separation of whey proteins was conducted on 40 samples from 5 mares. The total N, casein N, and true whey protein N contents showed a statistically significant decrease from day 4 to day 40, and then remained unvaried. In general, the nitrogen distribution of mare’s milk significantly changed between day 4 and day 20 and then remained almost unchanged until day 180 (except for the day 150 value, which showed a statistically significant increase for CN × 100/TN). β-Lactoglobulin and serum albumin contents showed a marked reduction, of 27 and 45.5%, respectively, between day 4 and day 20, and then remained unchanged; α-lactalbumin and immunoglobulins contents had a reduction of 24.7 and 38.3%, respectively, between day 4 and day 20, and another decrease between day 20 and day 40, of 20 and 32.8%, respectively. All whey proteins, expressed as a percentage on the total sum of the four whey proteins considered, did not vary significantly during lactation. However, the sum on the two whey proteins of mammary gland origin (β-Lg + α-La) increased between day 4 and day 20 by 6.3%, and between day 20 and day 40 by 3.8%; the sum of the whey proteins of blood origin (SA + Ig) showed an opposite trend, with a decrease by 14.5% between day 4 and day 20 and by 11% between day 20 and day 40. Key words: Mare’s milk, lactation stage, whey protein distribution, reversed-phase HPLC

Ten Haflinger nursing mares were controlled throughout a whole lactation period. Mares (400–540 kg live weight; 4–12 parities) were reared in a stud in Brescia province (Northern Italy). Eighty milk samples were taken by hand milking of one gland at days 4, 20, 40, 60, 80, 120, 150 and 180 post-partum. From days 4 to 180 post-partum, the ash content dropped from 0.58 to 0.28 g/100 g of milk (P

Milk composition of mammallian species varies widely with reference to genetic, physiological and nutritional factors and environmental conditions. In this survey, the composition of mare's milk is reviewed and compared to human and cow's milk, considering principal protein fractions and fatty acid content. Protein content in mare's milk is higher than in human milk and lower than in cow's milk; casein concentration in mare's milk is intermediate between the other two milks. Fat content is lower in mare's milk compared to human and cow's milk. Distribution of di- and tri-glycerides in mare's and women’ milk is similar. The proportion of polyunsaturated fatty acids in mare's and human milk is remarkably higher than in cow's milk. Mare's milk shows some structural and functional peculiarities that make it more suitable for human nourishment than cow's milk.

Using a combination of molecular modeling and spectroscopic experiments, the naturally occurring, pharmacologically active hypericin compound is shown to form a stable complex with the dimeric form of beta-lactoglobulin (beta-LG). Binding is predicted to occur at the narrowest cleft found at the interface between monomers in the dimeric beta-LG. The complex is able to preserve the fluorescence and singlet oxygen photosensitizing properties of the dye. The equilibrium constant for hypericin binding has been determined as K-a = 1.40 +/- 0.07 mu M-1, equivalent to a dissociation constant, K-d = 0.71 +/- 0.03 mu M. The complex is active against Staphylococcus aureus bacteria. Overall, the results are encouraging for pursuing the potential application of the complex between hypericin and beta-LG as a nanodevice with bactericidal properties for disinfection.

The trends of the physicochemical properties, chemical constituents and main nitrogen fractions of Haflinger mare milk were studied. Milk samples were collected at d 4, 20, 40, 60, 80, 120, 150 and 180 post-partum, by hand-milking from 5 mares, 7-14 years old (4-11 parities) and 400-490 kg live weight. Density, pH, titratable acidity, fat, protein, lactose and ash varied significantly during the first lactation period, while the freezing point showed statistically no significant modifi- cations. The contents of fat, protein and ash diminished. In addition, the gross energy value tended to decrease and the lactose content increased. Total N content decreased significantly ( P 0.05). Haflinger horse / nursing mare / lactation stage / milk properties / milk composition / nitrogen fractions

The “maturation” of milk for Parmigiano-Reggiano cheese is characterised by natural creaming process: the full cream milk is placed in large flat vats, for about 10-12 hours, to obtain the gravity separation of milk fat. The modifications of mineral equilibria and technological properties of milk during the “maturation” phase, were studied. To this aim 24 full cream (FC) milk samples and the corresponding partially skimmed (PS) milk, by natural creaming, were analysed. PS milk evidenced higher values of both colloidal Ca/casein (+4.28%; P£0.01) and colloidal P/casein (+4.02%; P£0.01) ratios than FC milk. An increase of pH (+0.028; P£0.01) and titratable acidity (+0.03 °SH/50ml; P£0.01) was observed during the milk “maturation”. The PS milk was characterised by a higher milk clotting time (r) (+7.91%; P£0.01) and a lower curd firmness (a30) (−16.75%; P£0.01) than FC milk. Concerning rheological properties, PS milk curd was characterised by higher values of both resistance to compression (+14.82%; P£0.01) and resistance to cut (+15.12%; P£0.01) than FC milk. The variations of milk characteristics observed in PS milk seems to indicate a structural modification of the native micelle during the “maturation” phase; this feature contributed to variations of rennet-coagulation and rheological properties observed in PS milk.

The peculiar characteristics of Parmigiano-Reggiano, cheese of Protected Designation of Origin (PDO), depend on its handicraft technology. The properties of casein micelles influence in an important way the physico-chemical phenomena of the cheese making process (Bozzetti et al., 1993).

Aim of this research was to study the effect of somatic cell count on mineral content and salt equilibria at the level of quarter milk samples. Ten Italian Friesian cows, in which two homologous quarters (front quarters in 1 cow, rear quarters in 6 cows and both rear and front quarters in 3 cows) were characterised by a milk SCC 400,000 cells/mL (HC-milk), respectively, were selected. Cows were milked at quarter level during the morning milking and a single sample was collected from each selected quarter, thus, 26 quarter milk samples were collected. Compared to LC-milk, HC-milk was characterised by a lower content of phosphorus and potassium and by a higher content of both sodium and chloride. The equilibrium of calcium, phosphorus and magnesium between the colloidal and soluble phase of milk and the mineralisation degree of the casein micelles, were not different between HC and LC milk.

The aim of this research was to study the effects of dairy maturation on the physico-chemical characteristics and technological properties of milk used for Parmigiano-Reggiano cheese manufacture. Three different operating conditions (CF1, CF2 and CF3) were considered. Full cream milk from the evening milking was stored on the farm and delivered to the cheese factory in churns (CF1) or in thermoregulated tanks at a temperature not lower than 18°C (CF2 and CF3). The natural creaming (10–12 h overnight) was performed in a traditional large flat vat containing 10–12 hl (CF1 and CF2) or in thermoregulated large flat vats containing 60 hl at about 15°C (CF3). Twenty-four, 24 and 22 maturation trials were performed in CF1, CF2, and CF3, respectively, during 2 consecutive years. A significant increase (P⩽0·05) in pH during the maturation of milk was observed in CF1 and CF2. The increase of pH was higher (P⩽0·05) in CF1 than CF2 and CF3. The values of titratable acidity were higher (P⩽0·05) in partially skimmed evening (PS) milk than in full cream (FC) milk in each operative condition. The increase observed in CF2 was higher than those reported in CF1 and CF3. Compared with FC milk, PS milk showed lower values (P⩽0·05) of casein and casein number and higher contents (P⩽0·05) of whey proteins and, particularly, proteose-peptone. The increase of proteose-peptone – per 100 g SNF or 100 g casein – was significantly higher (P⩽0·05) in CF1 than in CF2 and, in particular, than in CF3. A higher increase (P⩽0·05) of resistance to compression was observed in CF1 with respect to CF3. CF2 variation was not different with respect to either CF1 or CF3. Variation of the difference between PS and FC milks (PS-FC) in pH, TBC and fat were clearly lower in CF3 than CF1. This means that the control of milk temperature throughout the whole maturation phase offers a greater control of both microbial development and extent of creaming.

The aim of this research was to evaluate the effect of the modification of diet starch content on milk composition and onits nitrogen and mineral fractions. Ten Italian Friesian primiparous cows were randomly assigned to two groups and feda basal total mixed ration, (BSD, basal starch diet, 24.9% starch/DM) until 42 days in milking (DIM). At 43 DIM, 5 animals(control group, CTR) continued to receive the same ration and the remaining 5 cows (experimental group, EXP)were fed a low starch diet (LSD, 21.0% starch/DM) until 65 DIM, followed by a high starch diet (HSD, 28.3% starch/DM)66 to 85 DIM. From 86 DIM until 94 DIM, cows of the EXP group returned to the BSD. Milk samples were collected at 37,50, 60, 70, 80, 94 DIM. Starch intake was lower for EXP at DIM 50, 60 and higher at 70 and 80 DIM (P < 0.01). Milkyield and fat corrected milk (FCM) did not vary between groups and times of sampling, but HSD caused a significant (P< 0.05) reduction of milk fat in the EXP animals. NPN and MUN contents were affected by dietary treatments at 80 DIM(P < 0.05), being higher in CTR and lower in EXP group in comparison to their basal values (37 DIM). The αs1-caseinpercentages at 80 and 94 DIM increased in the EXP but not in the CTR group, and a marked decrease of αs2-casein percentagefor the EXP group at 94 DIM was observed (P < 0.05). Milk sodium content decreased at 80 and 94 DIM and thesodium to potassium ratio was reduced after the return to the basal diet in the EXP group (94 DIM), indicating that dietarystarch variations can be involved in the control of epithelium integrity of mammary gland in early lactation.

The aim of this research was to study the effects of the CSN1AG allele on the main rennet coagulation properties of milk. The study was carried out on individual milk samples with low αs1-casein obtained from 19 Italian Brown cows heterozygous for the CSN1AG allele (seventeen CSN1A BG and two CSN1A CG) from four herds in the province of Parma (Italy). Control cows (sixteen CSN1A BB and three CSN1A BC) giving milk with normal αs1-casein levels were chosen from within the same herds in order to establish pairs of cows with identical environment and management conditions, and comparable lactation stages and numbers. Individual milk samples from single pairs of cows with somatic cell counts and lactose and chloride levels within the normal ranges were collected and analysed in parallel. Rennet coagulation properties of milk were analysed using Formagraph and Gel Tester. Milk from low αs1-casein cows was characterized by lower casein content, lower titratable acidity and a higher proportion of κ-casein in total casein. The clotting time of this milk was ∼ 23% lower than that obtained with milk from normal αs1-casein cows. Rennet curd from low αs1-casein milk was obtained more rapidly and had a higher final firmness: curd-firming time was ∼ 35% lower and curd firmness measured 30 min after rennet addition was ∼ 27 % higher compared with that for normal αs1-casein milk. In addition, curd from low αs1-casein milk had a higher resistance to compression. These results suggest that, although a role for the CSN2 locus cannot be definitely excluded, the CSN1AG allele can considerably affect the main rennet coagulation properties of milk.