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Lourdes Cabezas - One of the best experts on this subject based on the ideXlab platform.
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biogenic amine content and proteolysis in Manchego Cheese manufactured with lactobacillus paracasei subsp paracasei as adjunct and other autochthonous strains as starters
International Dairy Journal, 2015Co-Authors: J.m. Poveda, Rosa Chicón, Lourdes CabezasAbstract:Abstract Two different autochthonous strain starter cultures, in which the acidifying starter was composed of strains of Lactococcus lactis, were used for the manufacture of pasteurised milk Manchego Cheese. Proteolysis parameters, biogenic amines and sensory characteristics were evaluated and compared with those of commercial starter Manchego Cheese and raw milk Manchego Cheese manufactured without starter. Autochthonous starter Cheeses, and especially those including Lactobacillus paracasei subsp. paracasei as adjunct, presented higher levels of proteolysis than in commercial starter Cheese. The concentrations of total biogenic amines in autochthonous starter Cheeses were much lower than in raw milk Cheese and even lower than in commercial starter Cheese. Cheese manufactured with the adjunct strain gave the best results for both flavour intensity and flavour quality, and was the most preferred by panellists. The results suggest that the culture containing Lb. paracasei subsp. paracasei as adjunct could be used for the manufacture of industrial Manchego Cheese.
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Volatile composition and improvement of the aroma of industrial Manchego Cheese by using Lactobacillus paracasei subsp. paracasei as adjunct and other autochthonous strains as starters
European Food Research and Technology, 2014Co-Authors: Justa M. Poveda, Pedro Nieto-arribas, Susana Seseña, Llanos Palop, Rosa Chicón, Lucía Castro, Lourdes CabezasAbstract:The use of several autochthonous strains of lactic acid bacteria, including Lactobacillus paracasei subsp . paracasei as adjunct of the starter in the manufacture of Manchego Cheese, was evaluated in an attempt to improve the aroma of the industrial Manchego Cheese. Volatile composition and odour characteristics were evaluated and compared to those in Manchego Cheese manufactured with a commercial starter (CS) culture and with raw milk Cheese manufactured without starter. Manchego Cheeses manufactured with two autochthonous strains of Lactococcus lactis subsp . lactis displayed a similar volatile profile and odour characteristics to the Cheese made with the CS. The use of the strain Lactobacillus paracasei subsp . paracasei CECT 7882 as adjunct of the Lactococcus strains produced Cheeses with higher amounts of some free fatty acids and alcohols, acetoin, lactones, phenylacetaldehyde, 2-phenylethanol and linalool, and higher scores of the odour intensity, odour quality, and ewe’s milk odour than the CS Cheeses. It resulted in an intensification and improvement of industrial Manchego Cheese aroma.
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genotypic and technological characterization of leuconostoc isolates to be used as adjunct starters in Manchego Cheese manufacture
Food Microbiology, 2010Co-Authors: Pedro Nietoarribas, Susana Seseña, J.m. Poveda, Llanos Palop, Lourdes CabezasAbstract:Twenty-seven Leuconostoc (Ln.) isolates from Manchego Cheese were characterized by phenotypic and genotypic methods, and their technological abilities studied in order to test their potential use as dairy starter components. While phenotypic diversity was evaluated by studying the biochemical characteristics of technological interest (i.e. acidifying and aminopeptidase activities), genotypic diversity was evidenced by using Randomly Amplified Polymorphic DNA-Polymerase Chain Reaction (RAPD-PCR). Additional technological abilities such as lipolytic, proteolytic and autolytic activities, salt and pH tolerance and production of dextran, flavour compounds and biogenic amines, were investigated. The marked differences among strains reflected the existing biodiversity in naturally fermented products. After statistically evaluating their performance, strains C0W2, belonging to Ln. lactis, and C16W5 and N2W5, belonging to Ln. mesenteroides subsp. dextranicum, revealed the best properties to be used in mixed dairy starter cultures. This study evidences the fact that natural environments can be considered as a proper source of useful strains, for the dairy industry.
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Genotypic and technological characterization of Lactococcus lactis isolates involved in processing of artisanal Manchego Cheese.
Journal of applied microbiology, 2009Co-Authors: Pedro Nieto-arribas, Susana Seseña, J.m. Poveda, Llanos Palop, Lourdes CabezasAbstract:Aims: Genotypic and technological characterization of wild lactococci isolated from artisanal Manchego Cheese during the ripening process for selection of suitable starter cultures. Methods and Results: A total of 114 isolates of lactococci were typed using randomly amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR). Sixteen distinct RAPD-PCR patterns, at a similarity level of 73%, were obtained. On the basis of species-specific PCR reaction, the isolates were assigned to the species Lactococcus lactis subsp. lactis and Lactococcus lactis subsp. cremoris with L. lactis subsp. lactis being predominant at both dairies. Twenty-six isolates were technologically characterized to select those with the best properties. Most of them showed good technological properties although some could produce tyramine. Conclusions: The presence of coincident genotypes at both dairies has been demonstrated, which would suggest that they are well adapted to the Manchego Cheese environment. Interesting differences were found in the technological characterization and the potential role of autochthonous lactococci strains as starter culture has been displayed. Significance and Impact of the Study: The great economic importance of Manchego Cheese encouraged a deeper knowledge of its microbiota, to select strains with the best properties to use as starter cultures in industrial Manchego Cheeses, preserving the autochthonous characteristics.
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Technological characterization of Lactobacillus isolates from traditional Manchego Cheese for potential use as adjunct starter cultures
Food Control, 2009Co-Authors: Pedro Nieto-arribas, Susana Seseña, J.m. Poveda, Llanos Palop, Lourdes CabezasAbstract:Thirty Lactobacillus isolates from artisanal Manchego Cheeses, 10 belonging to Lactobacillus plantarum and 20 belonging to Lactobacillus paracasei subsp. paracasei, were examined for potential use as adjunct cultures. Isolates were screened for acidifying and amino-biogenic capacity, for proteolytic, lipolytic, autolytic and aminopeptidase activities, and for sensory characteristics in UHT coagulated milk. Most of the lactobacilli displayed high aminopeptidase and autolytic activities and low acidifying activity. Only one isolate was able to produce tyramine. When growing on milk 53.3% of the Lb. paracasei subsp. paracasei isolates were able to produce pleasant flavours. Strains PBL210 (Lb. plantarum) and PBL213 and PBL226 (Lb. paracasei subsp. paracasei) presented the best technological characteristics, and also were still viable and with unaltered properties after freeze-drying and storage for 12 months. For these reasons, these strains could be good candidates for inclusion as adjuncts in a starter culture to manufacture industrial Manchego Cheese.
J.m. Poveda - One of the best experts on this subject based on the ideXlab platform.
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biogenic amine content and proteolysis in Manchego Cheese manufactured with lactobacillus paracasei subsp paracasei as adjunct and other autochthonous strains as starters
International Dairy Journal, 2015Co-Authors: J.m. Poveda, Rosa Chicón, Lourdes CabezasAbstract:Abstract Two different autochthonous strain starter cultures, in which the acidifying starter was composed of strains of Lactococcus lactis, were used for the manufacture of pasteurised milk Manchego Cheese. Proteolysis parameters, biogenic amines and sensory characteristics were evaluated and compared with those of commercial starter Manchego Cheese and raw milk Manchego Cheese manufactured without starter. Autochthonous starter Cheeses, and especially those including Lactobacillus paracasei subsp. paracasei as adjunct, presented higher levels of proteolysis than in commercial starter Cheese. The concentrations of total biogenic amines in autochthonous starter Cheeses were much lower than in raw milk Cheese and even lower than in commercial starter Cheese. Cheese manufactured with the adjunct strain gave the best results for both flavour intensity and flavour quality, and was the most preferred by panellists. The results suggest that the culture containing Lb. paracasei subsp. paracasei as adjunct could be used for the manufacture of industrial Manchego Cheese.
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Enterococcus populations in artisanal Manchego Cheese: Biodiversity, technological and safety aspects
Food Microbiology, 2010Co-Authors: Pedro Nieto-arribas, Susana Seseña, J.m. Poveda, Luis Cabezas, Rosa Chicón, Llanos PalopAbstract:Enterococci represent a considerable proportion of the microbiota in Manchego Cheeses. In this study, a total of 132 enterococci isolated from good quality Manchego Cheeses from two dairies at different ripening times were genotypically characterized and identified using molecular techniques. Representative isolates from the clusters obtained after genotyping were assayed for some enzymatic activities considered to have a potential role in Cheese ripening, and for 2,3-butanedione and acetoin production, evaluation of odor intensity and appearance in milk and safety evaluation. Enterococcus faecalis was the predominant specie, accounting for 81.8% of the total isolates, while Enterococcus faecium, Enterococcus hirae and Enterococcus avium were present in low proportions. The number of genotypes involved at each ripening time varied both between dairies and with the ripening times; genotype E. faecalis Q1 being present in almost all the samples from both dairies. Eight isolates showed a higher proteolytic activity and 3 isolates produced high quantities of acetoin-diacetyl, for which reason they are interesting from a technological standpoint. A low antibiotic resistance was found and almost all the strains were susceptible to clinically important antibiotics. On the contrary, only four isolates (E. faecalis C4W1 and N0W5, and E. faecium N32W1 and C16W2) did not harbor some of the virulence genes assayed.
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genotypic and technological characterization of leuconostoc isolates to be used as adjunct starters in Manchego Cheese manufacture
Food Microbiology, 2010Co-Authors: Pedro Nietoarribas, Susana Seseña, J.m. Poveda, Llanos Palop, Lourdes CabezasAbstract:Twenty-seven Leuconostoc (Ln.) isolates from Manchego Cheese were characterized by phenotypic and genotypic methods, and their technological abilities studied in order to test their potential use as dairy starter components. While phenotypic diversity was evaluated by studying the biochemical characteristics of technological interest (i.e. acidifying and aminopeptidase activities), genotypic diversity was evidenced by using Randomly Amplified Polymorphic DNA-Polymerase Chain Reaction (RAPD-PCR). Additional technological abilities such as lipolytic, proteolytic and autolytic activities, salt and pH tolerance and production of dextran, flavour compounds and biogenic amines, were investigated. The marked differences among strains reflected the existing biodiversity in naturally fermented products. After statistically evaluating their performance, strains C0W2, belonging to Ln. lactis, and C16W5 and N2W5, belonging to Ln. mesenteroides subsp. dextranicum, revealed the best properties to be used in mixed dairy starter cultures. This study evidences the fact that natural environments can be considered as a proper source of useful strains, for the dairy industry.
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Genotypic and technological characterization of Lactococcus lactis isolates involved in processing of artisanal Manchego Cheese.
Journal of applied microbiology, 2009Co-Authors: Pedro Nieto-arribas, Susana Seseña, J.m. Poveda, Llanos Palop, Lourdes CabezasAbstract:Aims: Genotypic and technological characterization of wild lactococci isolated from artisanal Manchego Cheese during the ripening process for selection of suitable starter cultures. Methods and Results: A total of 114 isolates of lactococci were typed using randomly amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR). Sixteen distinct RAPD-PCR patterns, at a similarity level of 73%, were obtained. On the basis of species-specific PCR reaction, the isolates were assigned to the species Lactococcus lactis subsp. lactis and Lactococcus lactis subsp. cremoris with L. lactis subsp. lactis being predominant at both dairies. Twenty-six isolates were technologically characterized to select those with the best properties. Most of them showed good technological properties although some could produce tyramine. Conclusions: The presence of coincident genotypes at both dairies has been demonstrated, which would suggest that they are well adapted to the Manchego Cheese environment. Interesting differences were found in the technological characterization and the potential role of autochthonous lactococci strains as starter culture has been displayed. Significance and Impact of the Study: The great economic importance of Manchego Cheese encouraged a deeper knowledge of its microbiota, to select strains with the best properties to use as starter cultures in industrial Manchego Cheeses, preserving the autochthonous characteristics.
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Technological characterization of Lactobacillus isolates from traditional Manchego Cheese for potential use as adjunct starter cultures
Food Control, 2009Co-Authors: Pedro Nieto-arribas, Susana Seseña, J.m. Poveda, Llanos Palop, Lourdes CabezasAbstract:Thirty Lactobacillus isolates from artisanal Manchego Cheeses, 10 belonging to Lactobacillus plantarum and 20 belonging to Lactobacillus paracasei subsp. paracasei, were examined for potential use as adjunct cultures. Isolates were screened for acidifying and amino-biogenic capacity, for proteolytic, lipolytic, autolytic and aminopeptidase activities, and for sensory characteristics in UHT coagulated milk. Most of the lactobacilli displayed high aminopeptidase and autolytic activities and low acidifying activity. Only one isolate was able to produce tyramine. When growing on milk 53.3% of the Lb. paracasei subsp. paracasei isolates were able to produce pleasant flavours. Strains PBL210 (Lb. plantarum) and PBL213 and PBL226 (Lb. paracasei subsp. paracasei) presented the best technological characteristics, and also were still viable and with unaltered properties after freeze-drying and storage for 12 months. For these reasons, these strains could be good candidates for inclusion as adjuncts in a starter culture to manufacture industrial Manchego Cheese.
Margarita Medina - One of the best experts on this subject based on the ideXlab platform.
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Characteristics of Manchego Cheese made from pasteurized ewes' milk inoculated with a bacteriocin-producing adjunct culture
Milchwissenschaft-milk Science International, 2007Co-Authors: Marta Ávila, Margarita Medina, Sonia Garde, Nunez Monica SarriaAbstract:The potential of using a bacteriocin-producing Lactococcus lactis strain to induce lysis of a Streptococcus thermophilus culture, and to accelerate proteolysis and flavour formation in Manchego Cheese, has been investigated. Two vats of Cheese were manufactured from pasteurized ewes' milk in duplicate trials. Milk in the experimental vat was inoculated with L. lactis subsp. lactis 415, a nisin Z and lacticin 481 producer. L. lactis subsp. lactis INIA 415-2, a bacteriocin-nonproducing mutant, was used as mesophilic starter in both vats. Cheeses were ripened at 12°C and 85% RH for 90 days. Microbiological, physicochemical, enzymatic, proteolytic, textural and sensory characteristics of Cheeses were assessed: S. thermophilus counts were lowered by the bacteriocin, aminopeptidase activity was slightly increased during early ripening, and proteolysis (estimated by the o-phthaldialdehyde method) was significantly higher throughout ripening. In spite of the enhanced proteolysis, textural and sensory characteristics of Manchego Cheese were not significantly influenced by milk inoculation with the bacteriocin producer.
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Characteristics of Manchego Cheese manufactured from raw ewes' milk inoculated with a bacteriocin-producing adjunct culture
Milchwissenschaft-milk Science International, 2007Co-Authors: Marta Ávila, Margarita Medina, Sonia Garde, Nunez Monica SarriaAbstract:The effect of Lactococcus lactis subsp. lactis INIA 415, a nisin Z and lacticin 481 producer, on the characteristics of raw milk Manchego Cheese has been studied. Experimental Cheese was made from milk inoculated with the bacteriocin producer, and control Cheese from milk without it. Bacteriocin-nonproducing mutant L. lactis subsp. lactis INIA 415-2 and a bacteriocin-sensitive Streptococcus thermophilus culture were added to both vats. Cheeses were ripened at 12°C and 85% RH for 90 days. Lysis of S. thermophilus was not enhanced by the bacteriocin, and aminopeptidase activity was lower in experimental Cheese than in control Cheese. Proteolysis values (estimated by the o-phthaldialdehyde method) of experimental and control Cheeses did not differ, and textural characteristics (fracturability, elasticity and hardness) were not influenced either by the bacteriocin producer. Odour, aroma and taste of experimental Cheese received higher quality and intensity scores than those of control Cheese on day 30, but differences gradually disappeared afterwards.
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Control of Listeria monocytogenes by bacteriocins and monitoring of bacteriocin-producing lactic acid bacteria by colony hybridization in semi-hard raw milk Cheese
The Journal of dairy research, 2001Co-Authors: Eva Rodríguez, Pilar Gaya, Manuel Nuñez, Juan L. Arqués, Margarita MedinaAbstract:The ability of Listeria monocytogenes to grow at low temperatures and increase to hazardous levels during storage of dairy products is of great concern to the dairy industry. List. monocytogenes was detected in 3·6% of 774 cows' milk samples from 114 farms in Central Spain (Gaya et al . 1998). Ewes' and goats' milks produced in Spain had contamination levels of 2·2 and 2·6% respectively (Rodriguez et al . 1994; Gaya et al . 1996). List. monocytogenes may survive during the manufacture and ripening of most Cheese varieties, with higher risk in soft surface-ripened Cheeses owing to the rise in pH during ripening (Maisnier-Patin et al . 1992; Giraffa & Carminati, 1997). The efficacy with which actively growing bacteriocin-producing cultures inhibit List. monocytogenes in some Cheese varieties has been demonstrated. Nisin-producing starters inhibited List. monocytogenes V7 in Camembert Cheese (Maisnier-Patin et al . 1992) and List. innocua BL86/26 in raw ewes' milk Manchego Cheese (Rodriguez et al . 1998). A lacticin 3147-producing starter culture (McAuliffe et al . 1999) reduced List. monocytogenes Scott A levels in cottage Cheese. Inoculation of milk with enterocin AS-48-producing Enterococcus faecalis INIA 4 inhibited List. monocytogenes strains Ohio and Scott A during the manufacture and ripening of Manchego Cheese (Nunez et al . 1997). Semi-hard Cheese varieties from raw or pasteurized cows' milk mixed with different proportions of ewes' and/or goats' milk represent ∼ 50% of Spanish Cheese production. The objective of the present work was to evaluate the antilisterial activity of three bacteriocin-producing lactic acid bacteria strains isolated from milk (Rodriguez et al . 2000) during the manufacture and ripening of a semi-hard Cheese manufactured from raw milk.
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PCR detection of the structural genes of nisin Z and lacticin 481 in Lactococcus lactis subsp. lactis INIA 415, a strain isolated from raw milk Manchego Cheese
Biotechnology Letters, 2001Co-Authors: Sonia Garde, Pilar Gaya, Margarita Medina, Eva Rodríguez, Manuel NuñezAbstract:A Lactococcus strain with strong antimicrobial activity was isolated from raw milk Manchego Cheese during a survey on the production of bacteriocins by lactic acid bacteria present in raw milk Cheeses. It was identified as Lactococcus lactis subsp. lactis , phenotypically by its morphological and physiological characteristics and genotypically by a PCR technique. When tested for tolerance to known bacteriocins produced by lactococci, it was shown to be resistant to nisin A and nisin Z. The presence of genes encoding nisin and lacticin 481 was revealed by PCR techniques with specific probes. Sequences of the respective PCR amplified fragments matched sequences reported for nisin Z and lacticin 481.
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PCR detection of the structural genes of nisin Z and lacticin 481 in Lactococcus lactis subsp. lactis INIA 415, a strain isolated from raw milk Manchego Cheese
Biotechnology Letters, 2001Co-Authors: Sonia Garde, Pilar Gaya, Margarita Medina, Eva Rodríguez, Manuel NuñezAbstract:A Lactococcus strain with strong antimicrobial activity was isolated from raw milk Manchego Cheese during a survey on the production of bacteriocins by lactic acid bacteria present in raw milk Cheeses. It was identified as Lactococcus lactis subsp. lactis, phenotypically by its morphological and physiological characteristics and genotypically by a PCR technique. When tested for tolerance to known bacteriocins produced by lactococci, it was shown to be resistant to nisin A and nisin Z. The presence of genes encoding nisin and lacticin 481 was revealed by PCR techniques with specific probes. Sequences of the respective PCR amplified fragments matched sequences reported for nisin Z and lacticin 481.
Manuel Nuñez - One of the best experts on this subject based on the ideXlab platform.
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Proteolysis during ripening of Manchego Cheese made from raw or pasteurized ewes' milk. Seasonal variation.
The Journal of dairy research, 2005Co-Authors: Pilar Gaya, Manuel Nuñez, Carmen Sánchez, Estrella Fernández-garcíaAbstract:Changes in nitrogen compounds during ripening of 40 batches of Manchego Cheese made from raw milk (24 batches) or pasteurized milk (16 batches) at five different dairies throughout the year were investigated. After ripening for six months, degradation of p-kappa- and beta-caseins was more intense in raw milk Cheese and degradation of alpha(s2)-casein in pasteurized milk Cheese. Milk pasteurization had no significant effect on breakdown of alpha(s1)-casein. Hydrophobic peptide content did not differ between raw and pasteurized milk Cheese, whereas hydrophilic peptide content was higher in raw milk Cheese. There were no significant differences between seasons for residual caseins, but hydrophobic peptides were at a higher level in Cheese made in autumn and winter and hydrophilic peptides in Cheese made in winter and spring. Raw milk Cheese had a higher content of total free amino acids and of most individual free amino acids than pasteurized milk Cheese. The relative percentages of the individual free amino acids were significantly different for raw milk and pasteurized milk Cheeses. The relative percentages of Lys and lie increased, while those of Val, Leu and Phe decreased during ripening. There were also seasonal variations within the relative percentages of free amino acids. In raw milk Cheeses, Asp and Cys were relatively more abundant in those made in autumn, Glu and Arg in Cheeses made in winter, and Lys and Ile in Cheeses made in spring and summer. Biogenic amines were detected only in raw milk Cheese, with the highest levels of histamine, tryptamine and tyramine in Cheeses made in spring, winter and spring, respectively.
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Volatile fraction and sensory characteristics of Manchego Cheese. 2. Seasonal variation.
The Journal of dairy research, 2002Co-Authors: Estrella Fernández-garcía, Carmen Serrano, Manuel NuñezAbstract:An automatic purge and trap apparatus, coupled to a GC-MS was used to study the seasonal variability of the volatile fraction of raw milk Manchego Cheese. Both season and dairy significantly affected abundance of most volatile compounds. Most aldehydes, methyl ketones, n-alcohols, and secondary alcohols reached significantly higher concentrations in spring Cheeses. Branched chain alcohols showed significantly higher concentrations in autumn and winter Cheeses, while significantly higher amounts of diketones were found in summer Cheeses. Most ethyl esters reached higher concentrations in spring and winter Cheeses and lower in autumn Cheeses. Lower concentrations of α-pinene were found in spring Cheeses, and higher amounts of limonene were observed in winter Cheeses. Heptane and octane were significantly more abundant in summer Cheeses. No significant seasonal differences were found either for quality or intensity scores.
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Control of Listeria monocytogenes by bacteriocins and monitoring of bacteriocin-producing lactic acid bacteria by colony hybridization in semi-hard raw milk Cheese
The Journal of dairy research, 2001Co-Authors: Eva Rodríguez, Pilar Gaya, Manuel Nuñez, Juan L. Arqués, Margarita MedinaAbstract:The ability of Listeria monocytogenes to grow at low temperatures and increase to hazardous levels during storage of dairy products is of great concern to the dairy industry. List. monocytogenes was detected in 3·6% of 774 cows' milk samples from 114 farms in Central Spain (Gaya et al . 1998). Ewes' and goats' milks produced in Spain had contamination levels of 2·2 and 2·6% respectively (Rodriguez et al . 1994; Gaya et al . 1996). List. monocytogenes may survive during the manufacture and ripening of most Cheese varieties, with higher risk in soft surface-ripened Cheeses owing to the rise in pH during ripening (Maisnier-Patin et al . 1992; Giraffa & Carminati, 1997). The efficacy with which actively growing bacteriocin-producing cultures inhibit List. monocytogenes in some Cheese varieties has been demonstrated. Nisin-producing starters inhibited List. monocytogenes V7 in Camembert Cheese (Maisnier-Patin et al . 1992) and List. innocua BL86/26 in raw ewes' milk Manchego Cheese (Rodriguez et al . 1998). A lacticin 3147-producing starter culture (McAuliffe et al . 1999) reduced List. monocytogenes Scott A levels in cottage Cheese. Inoculation of milk with enterocin AS-48-producing Enterococcus faecalis INIA 4 inhibited List. monocytogenes strains Ohio and Scott A during the manufacture and ripening of Manchego Cheese (Nunez et al . 1997). Semi-hard Cheese varieties from raw or pasteurized cows' milk mixed with different proportions of ewes' and/or goats' milk represent ∼ 50% of Spanish Cheese production. The objective of the present work was to evaluate the antilisterial activity of three bacteriocin-producing lactic acid bacteria strains isolated from milk (Rodriguez et al . 2000) during the manufacture and ripening of a semi-hard Cheese manufactured from raw milk.
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PCR detection of the structural genes of nisin Z and lacticin 481 in Lactococcus lactis subsp. lactis INIA 415, a strain isolated from raw milk Manchego Cheese
Biotechnology Letters, 2001Co-Authors: Sonia Garde, Pilar Gaya, Margarita Medina, Eva Rodríguez, Manuel NuñezAbstract:A Lactococcus strain with strong antimicrobial activity was isolated from raw milk Manchego Cheese during a survey on the production of bacteriocins by lactic acid bacteria present in raw milk Cheeses. It was identified as Lactococcus lactis subsp. lactis , phenotypically by its morphological and physiological characteristics and genotypically by a PCR technique. When tested for tolerance to known bacteriocins produced by lactococci, it was shown to be resistant to nisin A and nisin Z. The presence of genes encoding nisin and lacticin 481 was revealed by PCR techniques with specific probes. Sequences of the respective PCR amplified fragments matched sequences reported for nisin Z and lacticin 481.
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PCR detection of the structural genes of nisin Z and lacticin 481 in Lactococcus lactis subsp. lactis INIA 415, a strain isolated from raw milk Manchego Cheese
Biotechnology Letters, 2001Co-Authors: Sonia Garde, Pilar Gaya, Margarita Medina, Eva Rodríguez, Manuel NuñezAbstract:A Lactococcus strain with strong antimicrobial activity was isolated from raw milk Manchego Cheese during a survey on the production of bacteriocins by lactic acid bacteria present in raw milk Cheeses. It was identified as Lactococcus lactis subsp. lactis, phenotypically by its morphological and physiological characteristics and genotypically by a PCR technique. When tested for tolerance to known bacteriocins produced by lactococci, it was shown to be resistant to nisin A and nisin Z. The presence of genes encoding nisin and lacticin 481 was revealed by PCR techniques with specific probes. Sequences of the respective PCR amplified fragments matched sequences reported for nisin Z and lacticin 481.
José Ángel Gómez-ruiz - One of the best experts on this subject based on the ideXlab platform.
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Influence of a defined-strain starter and Lactobacillus plantarum as adjunct culture on volatile compounds and sensory characteristics of Manchego Cheese
European Food Research and Technology, 2008Co-Authors: José Ángel Gómez-ruiz, Isabel Martínez-castro, Lourdes Cabezas, Miguel Ángel González-viñas, Justa M. PovedaAbstract:Three batches of Manchego Cheese were manufactured using one of the following starter culture systems: (1) a defined strain starter culture comprising Lactococcus lactis subsp. lactis and Leuconostoc mesenteroides subsp. dextranicum ; (2) the above-defined strain starter culture and an adjunct culture ( Lactobacillus plantarum ), all these strains being isolated from high-quality Manchego Cheeses and (3) a commercial starter consisting of two strains of Lactococcus lactis . Differences in volatile profile and the sensory characteristics of these Cheeses were studied. After 4 months of ripening, the two batches of Cheese made with the defined strain starter cultures obtained the highest scores for sensory attributes and for the overall impression. Additionally, Purge & Trap and SDE analysis showed a more complex volatile profile in these Cheeses than in those made with the commercial starter. Extending the maturation time to 8 months for Cheeses made with the defined starter cultures led to significant higher levels of free fatty acids and ethyl esters in those Cheeses made without adjunct culture. However, panelists did not find significant differences among the sensory characteristics of the two Cheeses.
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Taste and flavor of artisan and industrial Manchego Cheese as influenced by the water-soluble extract compounds
European Food Research and Technology, 2007Co-Authors: Gonzalo Taborda, Lourdes Amigo, Mercedes Ramos, Isabel Martínez-castro, José Ángel Gómez-ruiz, Elena MolinaAbstract:The correlation between chemical and sensory analysis of the water-soluble extract compounds with molecular weight less than 1,000 Da (WSE < 1,000 Da) from Manchego Cheese at different stages of ripening, as well as the influence of the pasteurization processes, has been studied. Free amino acids, peptides and volatile compounds were more abundant in raw milk Cheeses WSE < 1,000 Da. Further fractionation of the WSE < 1,000 Da was carried on by gel permeation chromatography and amino acids, peptides, ions and volatiles were determined in the fractions. The same fractions were also subjected to organoleptic evaluation. Volatile compounds were related to the aroma and small peptides and amino acids to the taste. Volatile compounds were mainly alcohols and ketones. Fresh and floral notes were detected in the 4-month-old Cheeses, which evolved into more intense and complex flavors in the 8-month-old Cheeses. Peptides detected in the fractions were mainly hydrophilic. Umami taste was predominant in most of the fractions and it could be related to the presence of glutamic and aspartic acids in these fractions. Salty taste was perceived with high intensity in the fractions with a high content of salts. Bitter taste was mainly detected in the last eluting fractions and it was attributed to the Tyr, Phe and Trp residues found in these fractions.
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Sensory and mass spectrometric analysis of the peptidic fraction lower than one thousand daltons in Manchego Cheese.
Journal of dairy science, 2007Co-Authors: José Ángel Gómez-ruiz, Lourdes Amigo, Mercedes Ramos, Gonzalo Taborda, Elena MolinaAbstract:A total of 107 different peptides, all derived from alphaS1-, alphaS2-, and beta-casein, were identified in different fractions of artisan or industrial Manchego Cheese at 4 and 8 mo of ripening, and their sequences were examined. Most of these peptides are described for the first time in Manchego Cheese. Taste characteristics (umami and bitter) were assigned based on their AA sequence and the position of these AA within the sequence. The umami taste was predominant in all fractions analyzed by the panelists, and the peptides EQEEL, QEEL, and EINEL, containing a high number of glutamic residues, were found within the fractions. However, in several fractions described as having umami characteristics, no peptides responsible for this taste were detected. Therefore, compounds other than peptides seem to be involved in the umami properties of water-soluble extracts lower than 1,000 Da of Manchego Cheese.
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Short communication: Identification of the aroma compounds responsible for the floral/rose flavor in water-soluble fractions of Manchego Cheese.
Journal of dairy science, 2007Co-Authors: P.lópez Soto-yarritu, Lourdes Amigo, Isabel Martínez-castro, Gonzalo Taborda, José Ángel Gómez-ruizAbstract:Water-soluble fractions from Protected Denomination of Origin Manchego Cheese, with molecular weight
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Identification and formation of angiotensin-converting enzyme-inhibitory peptides in Manchego Cheese by high-performance liquid chromatography-tandem mass spectrometry.
Journal of chromatography. A, 2004Co-Authors: José Ángel Gómez-ruiz, Mercedes Ramos, Isidra RecioAbstract:A total of 75 peptides included in the fraction with molecular mass below 3000 from an 8-month-old Manchego Cheese could be identified using HPLC coupled on line to an ion trap mass spectrometer. Some previously described peptides with antihypertensive and/or angiotensin-converting enzyme (ACE)-inhibitory activity were detected. The formation of five active sequences was followed during Cheese ripening in four different batches of Manchego Cheese. Two experimental batches of Manchego Cheese elaborated with selected bacterial strains with the aim of improve the organoleptic characteristics demonstrated also a good performance in the formation of peptides with ACE-inhibitory activity during Cheese ripening.