The Experts below are selected from a list of 42 Experts worldwide ranked by ideXlab platform
Robert C. Lindsay - One of the best experts on this subject based on the ideXlab platform.
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Volatile Branched-chain Fatty Acids and Phenolic Compounds in Aged Italian Cheese Flavors
Journal of Food Science, 1991Co-Authors: J.k. Ha, Robert C. LindsayAbstract:Analysis of Cheeses by capillary gas chromatography (GC) revealed adequate concentrations of certain branched-chain fatty acids (BCFAs) and phenols present to contribute distinctive flavors. Butyric acid-like flavors in cow's milk Romano Cheese were modified by 2-methyl-butanoic and 2-ethylbutanoic acids which provided sweet, fruity notes. 4-Ethyloctanoic acid provided a characterizing goaty note to Romano Cheese made from mixed goats’and cows’milk. 4-Methyloctanoic and 4-ethyloctanoic acids along with p-cresol, m-cresol, and 3,4-Di-methylphenol appeared responsible for sheepy notes in sheep milk Romano Cheese. Phenol and cresols (o, m, p) strongly contributed phenolic and medicinal flavor notes to smoked Provolone Cheese. Low concentrations of BCFAs and phenols appeared to provide desirable background flavors to Parmesan Cheeses.
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Volatile Branched‐chain Fatty Acids and Phenolic Compounds in Aged Italian Cheese Flavors
Journal of Food Science, 1991Co-Authors: Robert C. LindsayAbstract:Analysis of Cheeses by capillary gas chromatography (GC) revealed adequate concentrations of certain branched-chain fatty acids (BCFAs) and phenols present to contribute distinctive flavors. Butyric acid-like flavors in cow's milk Romano Cheese were modified by 2-methyl-butanoic and 2-ethylbutanoic acids which provided sweet, fruity notes. 4-Ethyloctanoic acid provided a characterizing goaty note to Romano Cheese made from mixed goats’and cows’milk. 4-Methyloctanoic and 4-ethyloctanoic acids along with p-cresol, m-cresol, and 3,4-Di-methylphenol appeared responsible for sheepy notes in sheep milk Romano Cheese. Phenol and cresols (o, m, p) strongly contributed phenolic and medicinal flavor notes to smoked Provolone Cheese. Low concentrations of BCFAs and phenols appeared to provide desirable background flavors to Parmesan Cheeses.
A Pirisi - One of the best experts on this subject based on the ideXlab platform.
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survival of selected pathogenic bacteria during pdo pecorino Romano Cheese ripening
Dairy, 2020Co-Authors: Giacomo Lai, Margherita Addis, R Melillo, M Pes, Antonio Fadda, A PirisiAbstract:This study was conducted to assess, for the first time, the survival of the pathogenic bacteria Listeria monocytogenes, Salmonella spp., Escherichia coli O157:H7, and Staphylococcus aureus during the ripening of protected designation of origin (PDO) Pecorino Romano Cheese. A total of twenty-four Cheese-making trials (twelve from raw milk and twelve from thermized milk) were performed under the protocol specified by PDO requirements. Sheep Cheese milk was first inoculated before processing with approximately 106 colony-forming unit (CFU) mL−1 of each considered pathogen and the experiment was repeated six times for each selected pathogen. Cheese composition and pathogens count were then evaluated in inoculated raw milk, thermized milk, and Cheese after 1, 90, and 150 days of ripening. pH, moisture, water activity, and salt content of Cheese were within the range of the commercial PDO Pecorino Romano Cheese. All the Cheeses made from raw and thermized milk were microbiologically safe after 90 days and 1 day from their production, respectively. In conclusion, when Pecorino Romano Cheese is produced under PDO specifications, from raw or thermized milk, a combination of factors including the speed and extent of curd acidification in the first phase of the production, together with an intense salting and a long ripening time, preclude the possibility of growth and survival of L. monocytogenes, Salmonella spp., and E. coli O157:H7. Only S. aureus can be still detectable at such low levels that it does not pose a risk to consumers.
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Physico-chemical characteristics and acidic profile of PDO Pecorino Romano Cheese: Seasonal variation
Small Ruminant Research, 2015Co-Authors: Margherita Addis, Myriam Fiori, M Pes, G. Riu, Enrico Salvatore, A PirisiAbstract:Pecorino Romano, a protected designation of origin (PDO) semi-cooked hard Cheese, is the best known Italian dairy product obtained from ovine milk and one of the most exported Italian Cheeses in the world. The aim of this work was to provide useful information on physico-chemical and nutritional characteristics of PDO Pecorino Romano Cheese taking into account the variability related to the season of Cheese manufacture. A total of 70 samples of Pecorino Romano Cheese, with a ripening time ranged from 7 to 8 months, and manufactured at different times of the year (from March to June) were analyzed. The month of production affected Cheese composition, and Cheeses produced in late winter and spring were characterized by a less fat and salt content and a higher protein content with respect to those produced in early summer. Also the biochemical processes of proteolysis and lipolysis were influenced by the seasonality of productions. In particular Cheeses produced at late winter were more proteolyzed and lipolyzed if compared with those manufactured at summer season. The nutritional value of Cheese fat, associated in particular with linolenic, rumenic and vaccenic acids content, decreased with the progress of season probably due to variation in animal feed, pasture availability and fatty acids composition of grass lipids.
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Effect of the use of three different lamb paste rennets on lipolysis of the PDO Pecorino Romano Cheese
International Dairy Journal, 2005Co-Authors: Margherita Addis, M Pes, G. Piredda, R. Di Salvo, Maria Francesca Scintu, A PirisiAbstract:Two rennet pastes were prepared from lambs on different diets, and then, together with a commercial lamb rennet paste, were used to produce protected designation of origin (PDO) Pecorino Romano Cheeses. Chymosin activity and lipolytic activity were higher in the prepared rennets than in the commercial rennet. Lipolysis was greatest in Cheese produced with one of the prepared rennets. Both quantitative and qualitative differences in free fatty acids were found in the Cheeses. The taste of Cheeses made with the prepared rennets was preferred by an expert sensory panel and also considered more piquant than that of Cheese made with commercial rennet. The results indicate that both the diet of the lambs and slaughtering conditions should be regulated to produce rennet that preserves the traditional characteristics of PDO Pecorino Romano Cheese. Both lipolytic and proteolytic properties of rennet pastes should be standardised for the preparation of such Cheeses.
Margherita Addis - One of the best experts on this subject based on the ideXlab platform.
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survival of selected pathogenic bacteria during pdo pecorino Romano Cheese ripening
Dairy, 2020Co-Authors: Giacomo Lai, Margherita Addis, R Melillo, M Pes, Antonio Fadda, A PirisiAbstract:This study was conducted to assess, for the first time, the survival of the pathogenic bacteria Listeria monocytogenes, Salmonella spp., Escherichia coli O157:H7, and Staphylococcus aureus during the ripening of protected designation of origin (PDO) Pecorino Romano Cheese. A total of twenty-four Cheese-making trials (twelve from raw milk and twelve from thermized milk) were performed under the protocol specified by PDO requirements. Sheep Cheese milk was first inoculated before processing with approximately 106 colony-forming unit (CFU) mL−1 of each considered pathogen and the experiment was repeated six times for each selected pathogen. Cheese composition and pathogens count were then evaluated in inoculated raw milk, thermized milk, and Cheese after 1, 90, and 150 days of ripening. pH, moisture, water activity, and salt content of Cheese were within the range of the commercial PDO Pecorino Romano Cheese. All the Cheeses made from raw and thermized milk were microbiologically safe after 90 days and 1 day from their production, respectively. In conclusion, when Pecorino Romano Cheese is produced under PDO specifications, from raw or thermized milk, a combination of factors including the speed and extent of curd acidification in the first phase of the production, together with an intense salting and a long ripening time, preclude the possibility of growth and survival of L. monocytogenes, Salmonella spp., and E. coli O157:H7. Only S. aureus can be still detectable at such low levels that it does not pose a risk to consumers.
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effect of protein to fat ratio of sheep milk on the composition rheological properties and yield of pdo pecorino Romano Cheese
Small Ruminant Research, 2018Co-Authors: Margherita Addis, Myriam Fiori, Gavino Nieddu, Stefano Furesi, Antonio PirisiAbstract:Abstract The aim of this work was to evaluate the effect of sheep milk protein-to-fat ratio (PFR) standardization, on the technological, physico-chemical and rheological properties of PDO Pecorino Romano Cheese in the summer period (June and July). Two levels of PFR were investigated: i) ∼0.90 standardised PFR (SPFR) and ii) ∼0.76 natural PFR (NPFR). SPFR Cheese had a lower fat content (34.2 ± 0.4 vs 36.8 ± 0.4) and a higher protein content (27.1 ± 0.3 vs 25.6 ± 0.8) than NPFR Cheese. Consequently it was more compact, cohesive and hard compared to the latter. These aspects may contribute to reduce the time of ripening required to achieve a Cheese suitable for grating use. In PDO Pecorino Romano Cheese, this feature is monitored by the moisture in nonfat substance (MNFS), which at 8 months of ripening must be ≤47.0%. The standardization of milk contributed to achieve the suitable value earlier (46.0 ± 0.3 vs 47.2 ± 0.5). The standardization of the protein/fat ratio in sheep milk did not induce any significant effect on the lipolysis or proteolysis progress in the Cheese during ripening. Increasing the PFR significantly increased the levels of protein but, significantly, reduced the levels of moisture in nonfat substance, fat-in-dry matter and salt-in-moisture. The percentage of milk fat recovered in the SPFR Cheese was significantly higher than in the NPFR Cheese. Increasing the PFR led to a significant decrease in the actual Cheese yield, but a significant increase occurred in the normalized Cheese yield. The final results prove that a standardization of PFR in Cheese milk has a marked effect on Cheese composition, fat recovery, and Cheese yield.
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Optimization of a newly established gas-chromatographic method for determining lactose and galactose traces: Application to Pecorino Romano Cheese
Journal of Food Composition and Analysis, 2018Co-Authors: Ilenia Idda, Margherita Addis, G. Piredda, Maria Francesca Scintu, Nadia Spano, Giovanni Galistu, Ignazio Ibba, Valeria Marina Nurchi, Maria Itria Pilo, Gavino SannaAbstract:Abstract In this work, we present and validate new gas-chromatographic with flame injection detector method to measure traces of lactose and galactose in Cheese. Analytes are first extracted from the matrix by repeated treatments with a 40% (v/v) methanol/water solution, followed by their silanization with a 2:1 mixture of trimethylsilylimidazole and trimethylchlorosilane. Validation parameters show excellent limits of detection and quantification, and very good precision and trueness. The method was tested with a wide sampling of Protected Designation of Origin (PDO) Pecorino Romano sheep Cheese (33 samples, different for geographic area of production, seasonality and ripening levels). For all of them, the concentration of lactose and galactose were always below the relevant limits of detection (i.e. 0.54 and 0.90 mg kg−1, respectively). On this basis, PDO Pecorino Romano sheep Cheese is, according to both European Community and European Food Safety Authority guidelines, a “lactose free” foodstuff, useful in the dietary management of patients with galactosaemia and of people who are lactose intolerant.
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Physico-chemical characteristics and acidic profile of PDO Pecorino Romano Cheese: Seasonal variation
Small Ruminant Research, 2015Co-Authors: Margherita Addis, Myriam Fiori, M Pes, G. Riu, Enrico Salvatore, A PirisiAbstract:Pecorino Romano, a protected designation of origin (PDO) semi-cooked hard Cheese, is the best known Italian dairy product obtained from ovine milk and one of the most exported Italian Cheeses in the world. The aim of this work was to provide useful information on physico-chemical and nutritional characteristics of PDO Pecorino Romano Cheese taking into account the variability related to the season of Cheese manufacture. A total of 70 samples of Pecorino Romano Cheese, with a ripening time ranged from 7 to 8 months, and manufactured at different times of the year (from March to June) were analyzed. The month of production affected Cheese composition, and Cheeses produced in late winter and spring were characterized by a less fat and salt content and a higher protein content with respect to those produced in early summer. Also the biochemical processes of proteolysis and lipolysis were influenced by the seasonality of productions. In particular Cheeses produced at late winter were more proteolyzed and lipolyzed if compared with those manufactured at summer season. The nutritional value of Cheese fat, associated in particular with linolenic, rumenic and vaccenic acids content, decreased with the progress of season probably due to variation in animal feed, pasture availability and fatty acids composition of grass lipids.
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Effect of the use of three different lamb paste rennets on lipolysis of the PDO Pecorino Romano Cheese
International Dairy Journal, 2005Co-Authors: Margherita Addis, M Pes, G. Piredda, R. Di Salvo, Maria Francesca Scintu, A PirisiAbstract:Two rennet pastes were prepared from lambs on different diets, and then, together with a commercial lamb rennet paste, were used to produce protected designation of origin (PDO) Pecorino Romano Cheeses. Chymosin activity and lipolytic activity were higher in the prepared rennets than in the commercial rennet. Lipolysis was greatest in Cheese produced with one of the prepared rennets. Both quantitative and qualitative differences in free fatty acids were found in the Cheeses. The taste of Cheeses made with the prepared rennets was preferred by an expert sensory panel and also considered more piquant than that of Cheese made with commercial rennet. The results indicate that both the diet of the lambs and slaughtering conditions should be regulated to produce rennet that preserves the traditional characteristics of PDO Pecorino Romano Cheese. Both lipolytic and proteolytic properties of rennet pastes should be standardised for the preparation of such Cheeses.
J.k. Ha - One of the best experts on this subject based on the ideXlab platform.
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Volatile Branched-chain Fatty Acids and Phenolic Compounds in Aged Italian Cheese Flavors
Journal of Food Science, 1991Co-Authors: J.k. Ha, Robert C. LindsayAbstract:Analysis of Cheeses by capillary gas chromatography (GC) revealed adequate concentrations of certain branched-chain fatty acids (BCFAs) and phenols present to contribute distinctive flavors. Butyric acid-like flavors in cow's milk Romano Cheese were modified by 2-methyl-butanoic and 2-ethylbutanoic acids which provided sweet, fruity notes. 4-Ethyloctanoic acid provided a characterizing goaty note to Romano Cheese made from mixed goats’and cows’milk. 4-Methyloctanoic and 4-ethyloctanoic acids along with p-cresol, m-cresol, and 3,4-Di-methylphenol appeared responsible for sheepy notes in sheep milk Romano Cheese. Phenol and cresols (o, m, p) strongly contributed phenolic and medicinal flavor notes to smoked Provolone Cheese. Low concentrations of BCFAs and phenols appeared to provide desirable background flavors to Parmesan Cheeses.
M Pes - One of the best experts on this subject based on the ideXlab platform.
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survival of selected pathogenic bacteria during pdo pecorino Romano Cheese ripening
Dairy, 2020Co-Authors: Giacomo Lai, Margherita Addis, R Melillo, M Pes, Antonio Fadda, A PirisiAbstract:This study was conducted to assess, for the first time, the survival of the pathogenic bacteria Listeria monocytogenes, Salmonella spp., Escherichia coli O157:H7, and Staphylococcus aureus during the ripening of protected designation of origin (PDO) Pecorino Romano Cheese. A total of twenty-four Cheese-making trials (twelve from raw milk and twelve from thermized milk) were performed under the protocol specified by PDO requirements. Sheep Cheese milk was first inoculated before processing with approximately 106 colony-forming unit (CFU) mL−1 of each considered pathogen and the experiment was repeated six times for each selected pathogen. Cheese composition and pathogens count were then evaluated in inoculated raw milk, thermized milk, and Cheese after 1, 90, and 150 days of ripening. pH, moisture, water activity, and salt content of Cheese were within the range of the commercial PDO Pecorino Romano Cheese. All the Cheeses made from raw and thermized milk were microbiologically safe after 90 days and 1 day from their production, respectively. In conclusion, when Pecorino Romano Cheese is produced under PDO specifications, from raw or thermized milk, a combination of factors including the speed and extent of curd acidification in the first phase of the production, together with an intense salting and a long ripening time, preclude the possibility of growth and survival of L. monocytogenes, Salmonella spp., and E. coli O157:H7. Only S. aureus can be still detectable at such low levels that it does not pose a risk to consumers.
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Physico-chemical characteristics and acidic profile of PDO Pecorino Romano Cheese: Seasonal variation
Small Ruminant Research, 2015Co-Authors: Margherita Addis, Myriam Fiori, M Pes, G. Riu, Enrico Salvatore, A PirisiAbstract:Pecorino Romano, a protected designation of origin (PDO) semi-cooked hard Cheese, is the best known Italian dairy product obtained from ovine milk and one of the most exported Italian Cheeses in the world. The aim of this work was to provide useful information on physico-chemical and nutritional characteristics of PDO Pecorino Romano Cheese taking into account the variability related to the season of Cheese manufacture. A total of 70 samples of Pecorino Romano Cheese, with a ripening time ranged from 7 to 8 months, and manufactured at different times of the year (from March to June) were analyzed. The month of production affected Cheese composition, and Cheeses produced in late winter and spring were characterized by a less fat and salt content and a higher protein content with respect to those produced in early summer. Also the biochemical processes of proteolysis and lipolysis were influenced by the seasonality of productions. In particular Cheeses produced at late winter were more proteolyzed and lipolyzed if compared with those manufactured at summer season. The nutritional value of Cheese fat, associated in particular with linolenic, rumenic and vaccenic acids content, decreased with the progress of season probably due to variation in animal feed, pasture availability and fatty acids composition of grass lipids.
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Effect of the use of three different lamb paste rennets on lipolysis of the PDO Pecorino Romano Cheese
International Dairy Journal, 2005Co-Authors: Margherita Addis, M Pes, G. Piredda, R. Di Salvo, Maria Francesca Scintu, A PirisiAbstract:Two rennet pastes were prepared from lambs on different diets, and then, together with a commercial lamb rennet paste, were used to produce protected designation of origin (PDO) Pecorino Romano Cheeses. Chymosin activity and lipolytic activity were higher in the prepared rennets than in the commercial rennet. Lipolysis was greatest in Cheese produced with one of the prepared rennets. Both quantitative and qualitative differences in free fatty acids were found in the Cheeses. The taste of Cheeses made with the prepared rennets was preferred by an expert sensory panel and also considered more piquant than that of Cheese made with commercial rennet. The results indicate that both the diet of the lambs and slaughtering conditions should be regulated to produce rennet that preserves the traditional characteristics of PDO Pecorino Romano Cheese. Both lipolytic and proteolytic properties of rennet pastes should be standardised for the preparation of such Cheeses.
