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1.
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.  相似文献   

2.
《International Dairy Journal》2003,13(2-3):169-178
Different authors have demonstrated the potential of adding lactobacilli as adjunct cultures to pasteurized milk used in cheese manufacture. The aim of this work was to observe the effect of the use of a defined-strain starter culture and the addition of an adjunct culture (Lactobacillus plantarum) to cheesemilk in order to determine their effect on the ripening of Manchego cheese. Manchego cheeses were manufactured using one of the following starter culture systems: a defined starter consisting of Lactococcus lactis ssp. lactis and Leuconostoc mesenteroides ssp. dextranicum; a defined starter, as described above, and Lb. plantarum, which were isolated from a good quality Manchego cheese made from raw milk, or a commercial starter comprised of two strains of Lc. lactis. The cheeses were sampled at 15, 45, 90 and 150 d of ripening. Principal component analysis of peak heights of reversed-phase HPLC chromatograms of 70% (v/v) ethanol-insoluble and -soluble fractions distributed the samples according to the starter used in their manufacture. Quantitative differences in several peptides were evident between the three cheeses. Cheeses made with the defined-strain starters received higher scores for the flavour quality and intensity and for overall impression than the cheeses made with the commercial starter.  相似文献   

3.
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.  相似文献   

4.
Raw milk cheeses have more intense flavours than cheeses made from pasteurized milk and harbour strains with potential adjunct properties. Two Lactobacillus paracasei strains, R-40926 and R-40937, were selected as potential adjunct cultures from a total of 734 isolates from good quality artisan raw milk Gouda-type cheeses on the basis of their prevalence in different cheese types and/or over several production batches, safety and technological parameters. Conventional culturing, isolation and identification and a combined PCR-DGGE approach using total cheese DNA extracts and DNA extracts obtained from culturable fractions were employed to monitor viability of the introduced adjuncts and their effect on the cheese microbiota. The control cheese made without adjuncts was dominated by members of the starter, i.e. Lactococcus lactis and Leuconostoc pseudomesenteroides. In the cheeses containing either R-40926 or R-40937, the respective adjuncts increased in number as ripening progressed indicating that both strains are well adapted to the cheese environment and can survive in a competitive environment in the presence of a commercial starter culture. Principal component analysis of cheese volatiles determined by steam distillation-extraction and gas chromatography-mass spectrometry could differentiate cheeses made with different concentrations of adjunct R-40926 from the control cheese, and these differences could be correlated to the proteolytic and lipolytic properties of this strain. Collectively, results from microbiological and metabolic analyses indicate that the screening procedure followed throughout this study was successful in delivering potential adjunct candidates to enrich or extend the flavour palette of artisan Gouda-type cheeses under more controlled conditions.  相似文献   

5.
The effects of microfiltration and pasteurization processes on proteolysis, lipolysis, and flavor development in Domiati cheese during 2 mo of pickling were studied. Cultures of starter lactic acid bacteria isolated from Egyptian dairy products were evaluated in experimental Domiati cheese for flavor development capabilities. In the first trial, raw skim milk was microfiltered and then the protein:fat ratio was standardized using pasteurized cream. Pasteurized milk with same protein:fat ratio was also used in the second trial. The chemical composition of cheeses seemed to be affected by milk treatment—microfiltration or pasteurization—rather than by the culture types. The moisture content was higher and the pH was lower in pasteurized milk cheeses than in microfiltered milk cheeses at d 1 of manufacture. Chemical composition of experimental cheeses was within the legal limits for Domiati cheese in Egypt. Proteolysis and lipolysis during cheese pickling were lower in microfiltered milk cheeses compared with pasteurized milk cheeses. Highly significant variations in free amino acids, free fatty acids, and sensory evaluation were found among the cultures used in Domiati cheesemaking. The cheese made using adjunct culture containing Lactobacillus delbrueckii ssp. lactis, Lactobacillus paracasei ssp. paracasei, Lactobacillus casei, Lactobacillus plantarum, and Enterococcus faecium received high scores in flavor acceptability. Cheeses made from microfiltered milk received a higher score in body and texture compared with cheeses made from pasteurized milk.  相似文献   

6.
The microbial dynamics of Dutch-type cheeses differing in starter (commercial DL starter or single strain of Lactococcus lactis ssp. cremoris), adjunct (Lactobacillus or Propionibacterium) and fat contents (10% or 28% fat) were investigated by culture-dependent and culture-independent analysis. The cheese microbiota was dominated by the adjunct Lactobacillus after 4 weeks of ripening and the fat content did not influence the microbial diversity. The Leuconostoc sp., presumably from the DL starter, was detected in cheeses made with added Lactobacillus plantarum and Lactobacillus rhamnosus and was not detected in cheese made with added Lactobacillus paracasei after 4 and 7 weeks. No Lactobacillus spp. were detected in cheese with added Propionibacterium, while Leuconostoc was the only species detected. In cheeses made with Lc. lactis ssp. cremoris as starter, the Lactobacillus microbiota was similar to the cheese milk microbiota after 24 h while after 4 weeks different species of Lactobacillus and Leuconostoc were detected.  相似文献   

7.
The influence of three probiotic strains (Lactobacillus acidophilus, Lactobacillus paracasei and Bifidobacterium lactis) in semi-hard cheese proteolysis patterns was assessed. Probiotics were inoculated both as single cultures and as a three-strain mix, and added to milk either after a pre-incubation step or directly to the vat. B. lactis did not show any effect on proteolysis of cheeses, while L. paracasei showed limited impact at the end of the ripening. In contrast, L. acidophilus significantly influenced secondary proteolysis from the beginning of ripening, causing an increase in the levels of small nitrogen-containing compounds and free amino acids and changes in the peptide profiles. The effect of Lactobacillus acidophilus on peptidolysis was more noticeable when it was added to cheese–milk after pre-incubation in an enriched milk fat substrate. Similar results obtained with the three-strain mixed culture, suggesting that L. acidophilus played a major role in secondary proteolysis of probiotic cheeses in this trial.  相似文献   

8.
The influence of bacteria and sunflower oil addition on conjugated linoleic acid content (CLA) in buffalo cheese was determined. Fresh and short-ripened cheeses were manufactured using the same starter culture and four different adjunct strains previously selected by their CLA production rate. Lactobacillus casei, Lactobacillus rhamnosus, Bifidobacterium bifidum and Streptococcus thermophilus were individually used as adjunct culture. Sunflower oil (SO) was added to obtain a final concentration of 200 μg/ml of linoleic acid. CLA levels in cheese were higher than raw milk, especially after ripening time. SO supplementation increase CLA concentrations in fresh cheeses, except in those manufactured with S. thermophilus as adjunct culture. Both, ripening and SO supplementation showed a positive influence on CLA concentration. Similar texture, acidity and colour were determined in cheeses with or without SO supplementation. Buffalo cheeses manufactured with appropriate adjunct cultures may be a natural source of CLA for human consumption.  相似文献   

9.
Paired wild‐type cultures consisting of a Lactobacillus paracasei subsp. paracasei (three strains) or Pediococcus pentosaceus (one strain) and a Pediococcus inopinatus (five strains) were used as adjunct cultures in the production of Iranian white brined cheese. After 8 weeks of ripening, adjunct‐treated cheeses produced by L. paracasei subsp. paracasei and P. inopinatus received significantly higher scores for flavour/taste, aroma, texture and overall preference than those produced by P. pentosaceus and P. inopinatus as well as the control cheese (P < 0.05). In conclusion, a greater improvement of sensory quality of cheeses was strongly associated with the presence of L. paracasei subsp. paracasei rather than pediococci.  相似文献   

10.
The isolation and identification of lactic acid bacteria (LAB) from raw ewes’ milk and traditional Pecorino Sardo cheese made from this milk without the addition of starter culture was carried out to define the autochthonous lactic microflora present in milk and the evolution of LAB during cheese ripening. Isolation of 275 strains belonging to different Lactococcus, Lactobacillus, Streptococcus and Enterococcus species was achieved. Coccal-shaped LAB were found to predominate during cheese fermentation, while lactobacilli were preponderate during the latter phase of ripening. The technological selection of a total of 174 LAB strains belonging to the species Lactococcus lactis, Streptococcus thermophilus, Lactobacillus helveticus and Lb. casei allowed an experimental starter to be prepared, in which a potentially probiotic species, Lb. casei was used. The suitability of the autochthonous starter culture was tested in cheese-making trials, using thermised ewes’ milk, by comparing experimental Pecorino Sardo cheese with a control cheese produced at industrial scale using a whey starter culture from previous batches of manufacture. In particular, microbiological and physicochemical parameters were determined over 210 days of cheese ripening. Although sensory evaluation did not show any significant difference between experimental and control Pecorino Sardo cheeses, the use of the selected autochthonous starter allowed the production of experimental cheese with a significantly higher level of free amino acids, in particular essential amino acids, in comparison with the Pecorino Sardo control cheeses.  相似文献   

11.
《Food microbiology》2004,21(2):233-240
Cheesemaking from batches of raw ewe's milk was carried out via inoculation with wild strains of Lactococcus lactis subsp. lactis ESB110019 and Lactobacillus plantarum ESB5004 independently, or combined with each other. Those two strains had been isolated from the native microflora of typical Serra da Estrela cheese. One control batch was processed in parallel without addition of any starter. The evolution in viable counts of the main micro-organisms (viz. lactic acid bacteria, Enterobacteriaceae, staphylococci and yeasts), as well as in secondary proteolysis (WSN, 2% TCASN, 12% TCASN and 5% PTASN), was monitored throughout ripening time (over a 63-day period) in cheeses from each batch. The sensory features of the fully ripened cheeses were also assessed. Cheeses manufactured with starter showed significantly lower levels of viable Enterobacteriaceae than those manufactured without starter; viable counts of enterococci and staphylococci did significantly increase after addition of L. lactis or Lb. plantarum, respectively. Proteolysis in terms of WSN and 5% PTASN was not significantly affected by the lactic acid bacteria tested when compared to the control, but L. lactis played a significant role toward increasing the 2% TCASN content of cheeses; both strains led to a statistically significant increase of the 12% TCASN. The scores for flavor and texture of the control cheeses were somewhat above those for the experimental cheeses manufactured with starter.  相似文献   

12.
Eighteen cultures of starter lactic acid bacteria with or without added adjunct cultures, isolated from Egyptian dairy products, were evaluated in experimental Ras cheese for flavour development. Chemical composition of experimental cheeses was within the legal limit for Ras cheese in Egypt. All cultures used in this study had no effect on chemical composition of Ras cheese. Very significant variations in free amino acids, free fatty acids and sensory evaluation have been found among the cultures used in Ras cheesemaking. The levels of free amino acids and free fatty acids were correlated well with flavour development in Ras cheese. Seven of the tested cultures produced acceptable flavour and texture of Ras cheese. The highest overall score of flavour intensity, flavour and texture acceptability were in cheese made using YY47 lactic culture in addition to adjunct culture of Lactobacillus helveticus, Lactobacillus paracasei subsp. paracasei, Lactobacillus delbrueckii subsp. lactis and Enterococcus faecium. This culture can be recommended for Ras cheese manufacture using pasteurized milk.  相似文献   

13.
The non-starter lactic acid bacteria (NSLAB) present in cheddar cheese manufactured in a commercial creamery was monitored phenotypically to the strain level over a period of 12 months to examine the effects of maturity status and manufacturing practices on the composition of the population. Five Lactobacillus spp. and Leuconostoc lactis were identified among the 459 isolates selected. The predominant NSLAB, Lactobacillus paracasei and Lactobacillus brevis, were present in 59 and 31% of the cheeses examined and represented 52.7 and 25.8%, respectively, of the isolates identified. Among the NSLAB screened 71 different phenotypic profiles were identified and these included 26 biotypes of Lb. paracasei, 14 Lb. brevis, 11 Lactobacillus plantarum, 10 Lactobacillus curvatus and 7 Leuc. lactis. The average number of strains recovered from a cheese was 3.9±2.1 and ranged from 1 to 11. Although approximately 70% of the cheese samples were dominated by three or less strains the NSLAB populations were heterogeneous and the majority (61.5%) were comprised of four or more strains of one or more species. Only 30 of the biotypes were recovered from more than one population. There was no evidence for the repeated recurrence of any of the strains isolated although some of the Lb. paracasei strains were present intermittently in cheeses throughout the 12-month manufacturing period. Six Lb. brevis strains also recurred in some of the cheeses produced in a limited period during the autumn. Pronounced shifts in the species complement and strain profile occurred during maturation, while the average number of strains present in the cheese decreased with increasing maturity. Microbiological examination of the NSLAB population of cheese either produced in different vats during the same production run or manufactured in the same vat but in different production runs (vat fills) indicated that the number of strains common to paired samples from two vats or a single vat in successive production runs was only 1.7±1.4 and 1.5±1.2, respectively, and confirmed the inherent variability that exists, both within and between production runs, in the non-starter population of cheese manufactured in a commercial creamery.  相似文献   

14.
Abstract: A dried tomato‐flavored probiotic cream cheese (P) containing Lactobacillus paracasei Lpc‐37 was developed for the purpose of this study. The same product, but without probiotic addition (C) was used as control. Lactococcus lactis subsp. lactis and Lactococcus lactis subsp. cremoris were used as lactic starter cultures. Chemical composition analyses and sensory tests were performed on days 1 and 7, respectively. Titratable acidity, pH value and L. paracasei population were determined every 7 d during the refrigerated storage (21 d) of the cream cheeses. The experiment and analyses were performed in triplicate, using standard methods. Probiotic population remained greater than 107 CFU/g throughout the storage period, thereby characterizing the product as potentially probiotic. Cream cheeses C and P did not differ on the sensory tests, both obtaining good overall acceptance by the consumers, of which 82.6% stated that they certainly or probably would buy the product. Practical Application: Lactobacillus paracasei Lpc‐37 is a probiotic bacterium and clinical studies have shown that this microorganism beneficially affects its host. In general, dried tomato‐flavored products and cream cheese are products with good acceptance by the consumers. Thus, regular consumption of the probiotic cream cheese developed in this study may have positive effects on health and well being of people if incorporated into their diet.  相似文献   

15.
Nonstarter lactic acid bacteria are the main uncontrolled factor in today's industrial cheese making and may be the cause of quality inconsistencies and defects in cheeses. In this context, adjunct cultures of selected lactobacilli from nonstarter lactic acid bacteria origin appear as the best alternative to indirectly control cheese biota. The objective of the present work was to study the technological properties of Lactobacillus strains isolated from cheese by in vitro and in situ assays. Milk acidification kinetics and proteolytic and acidifying activities were assessed, and peptide mapping of trichloroacetic acid 8% soluble fraction of milk cultures was performed by liquid chromatography. In addition, the tolerance to salts (NaCl and KCl) and the phage-resistance were investigated. Four strains were selected for testing as adjunct cultures in cheese making experiments at pilot plant scale. In in vitro assays, most strains acidified milk slowly and showed weak to moderate proteolytic activity. Fast strains decreased milk pH to 4.5 in 8 h, and continued acidification to 3.5 in 12 h or more. This group consisted mostly of Lactobacillus plantarum and Lactobacillus rhamnosus strains. Approximately one-third of the slow strains, which comprised mainly Lactobacillus casei, Lactobacillus fermentum, and Lactobacillus curvatus, were capable to grow when milk was supplemented with glucose and casein hydrolysate. Peptide maps were similar to those of lactic acid bacteria considered to have a moderate proteolytic activity. Most strains showed salt tolerance and resistance to specific phages. The Lactobacillus strains selected as adjunct cultures for cheese making experiments reached 108 cfu/g in soft cheeses at 7 d of ripening, whereas they reached 109 cfu/g in semihard cheeses after 15 d of ripening. In both cheese varieties, the adjunct culture population remained at high counts during all ripening, in some cases overcoming or equaling primary starter. Overall, proximate composition of cheeses with and without added lactobacilli did not differ; however, some of the tested strains continued acidifying during ripening, which was mainly noticed in soft cheeses and affected overall quality of the products. The lactobacilli strains with low acidifying activity showed appropriate technological characteristics for their use as adjunct cultures in soft and semihard cheeses.  相似文献   

16.
Seventeen Leuconostoc mesenteroides and 33 Lactobacillus paracasei subsp. paracasei from traditional Pecorino di Filiano cheese were tested for their potential use as adjunct starters, and a study of their genetic variability was carried out. Forty one per cent (41%) of Leumesenteroides and 46% of Lb. paracasei subsp. paracasei showed medium–high proteolytic activity, while high lipolytic activity was detected in 18% of Lb. paracasei subsp. paracasei. The aminopeptidase activity of Lb. paracasei subsp. paracasei was higher than that of Leumesenteroides. Strain diversity by RAPD analysis showed a high degree of heterogeneity. This study identified strains with unusual properties that could be good candidates as adjuncts in a starter to manufacture PF cheese.  相似文献   

17.
《International Dairy Journal》2005,15(6-9):795-805
Reduced-fat, semi-hard round-eyed cheese was made from bovine milk with a mesophilic DL-starter and three Lactobacillus paracasei subsp. paracasei single-strain adjuncts with different aminotransferase (AT) activity profiles. The pilot-plant procedure was not influenced by the adjuncts, and similar cheese was made from all vats. The growth of each adjunct to dominate the cheese was confirmed by using DNA fingerprinting. Flavour profiles were different for cheeses made with the different Lactobacillus strains. Use of the adjunct CHCC 4256 significantly increased the content of flavour compounds that were produced from the branched-chain amino acids (BcAAs: Leu, Ile and Val) and Asp. These cheeses also had superior sensory characteristics as they tasted aromatic and sweet without bitterness. The adjunct CHCC 4256 did not have glutamate dehydrogenase activity, or the highest activity on BcAA, but showed typical AT activity, with a similar activity on Leu, Phe and Asp substrates.  相似文献   

18.
This study compared the chemical composition and fatty acid (FA) profile of Manchego type cheese and Panela cheese made from hair sheep milk and compared these with both types of cheese manufactured with cow milk as a reference. In addition, this study aimed to determine differences in sensory characteristics between Manchego type cheeses manufactured with either hair sheep milk or cow milk. A total of 25 and 14 Manchego type cheeses from hair sheep milk and cow milk were manufactured, respectively. In addition, 30 and 15 Panela cheeses from hair sheep milk and cow milk were manufactured, respectively. The chemical composition and FA profile were determined in all cheeses. In addition, a sensory analysis was performed in Manchego type cheeses manufactured from either hair sheep milk or cow milk. Moisture content was lower in Manchego type cheeses (37.5 ± 1.26 and 37.5 ± 1.26 g/100 g in cheeses manufactured from hair sheep milk and cow milk, respectively) than in Panela cheeses (54.0 ± 1.26 and 56.1 ± 1.26 g/100 g in cheeses manufactured from hair sheep milk and cow milk, respectively). Ash, protein, and sodium contents were higher in Manchego type cheeses than in Panela cheeses. Manchego type cheese manufactured from hair sheep milk contained more C4:0, C6:0, C8:0, C10:0, C12:0, C14:0, C18:2 cis-9,cis-12, total saturated FA, total short-chain FA, total medium-chain FA, total polyunsaturated FA, and de novo FA than Manchego type cheeses from cow milk. Total content of short-chain FA was higher in hair sheep cheeses (24.4 ± 1.30 and 19.6 ± 1.30 g/100 g in Manchego type and Panela cheeses, respectively) than in cow cheeses (8.89 ± 1.30 and 8.26 ± 1.30 g/100 g in Manchego type and Panela cheeses, respectively). Manchego type cheeses from hair sheep milk obtained higher scores for odor (7.05), texture (6.82), flavor (7.16), and overall acceptance (7.16) compared with those made from cow milk (6.37, 6.12, 6.17, and 6.83, respectively). In conclusion, both Manchego type cheese and Panela cheese manufactured with hair sheep milk had a similar chemical composition and contained higher levels of short-chain FA, total polyunsaturated FA, and de novo FA than those manufactured with cow milk.  相似文献   

19.
This study characterised exopolysaccharide-producing lactic acid bacteria and examined their potential for use in Cheddar cheese manufacture. Two strains were chosen for incorporation as adjunct cultures in Cheddar cheese manufacture: namely, the homopolysaccharide-producers Weissella cibaria MG1 and Lactobacillus reuteri cc2. These strains both produce dextrans with molecular masses ranging from 105 to 107 Da. Both strains were used in the production of miniature Cheddar cheeses that employed a conventional commercial cheese starter culture Lactococcus lactis R604. A cheese was also included that used purified dextran as an ingredient. The W. cibaria strain survived in cheese with levels increasing by 1.5 log cycles over the ripening period. All experimental cheeses (adjunct or exopolysaccharide ingredient) had higher moisture levels compared with the control cheese made using starter alone. Inclusion of the adjunct strains had no detectable negative effects on cheeses in terms of proteolysis.  相似文献   

20.
Eleven lactic acid bacteria strains of importance to the dairy industry were subjected to in vitro analyses to determine their probiotic potential. Seven strains were isolated from ewe’s and cow’s milk (Enterococcus faecalis – five –, Lactococcus lactis and Lactobacillus paracasei). Four were obtained from American Type Culture Collection (ATCC), isolated from cheese (Lactobacillus casei 393), human feces (L. paracasei 27092 and Lactobacillus rhamnosus 53103) and used in cheese making (L. lactis 54104). Although none of the strains was able to degrade mucin, all E. faecalis showed, at least, one transferable antibiotic resistance, which excluded them as candidates for addition to foods. Of the remaining six safe strains, L. lactis strains were more tolerant to low pH than Lactobacillus spp.; all were tolerant to pancreatin and bile salts and showed antibacterial activity. The highest level of adhesion to Caco-2 cells was observed with L. lactis 660, even higher than L. rhamnosus ATCC 53103 (recognized probiotic and used as control). The physiological probiotic properties of these strains, mainly isolated from dairy sources, are interesting in view of their use in cheese productions as starter and non starter cultures. The five LAB safe strains studied may have potential as novel probiotics in the dairy foods.  相似文献   

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