Batches Of Cheese Research Articles

Fate of Yersinia enterocolitica during manufacture, ripening and storage of Lighvan cheese

This study aimed to evaluate the behavior of virulent Yersinia enterocolitica (YE) during the manufacture, ripening and storage of Lighvan cheese with particular reference to strains of YE, initial inoculation level, and storage time. Three strains of YE with low (1logcfu/ml) and high (3logcfu/ml) inoculation levels were inoculated to raw whole ewe's milk which was then used for manufacturing of Lighvan cheese. Throughout the manufacturing, ripening and storage periods the number of YE was counted on selective media. Enumerated colonies were then confirmed by duplex PCR using ail and virF genes. Moreover, some microbial and physiochemical characteristics of the cheese samples were examined. According to the results, initial inoculation level and storage time had statistically significant (P<0.01) effects on persistency of YE, while strain type exhibited no statistically significant (P>0.01) impact on survival of the pathogen. Results showed a rapid increase in the number of YE during manufacturing, however, in the ripening and storage periods the number of YE was decreased and eventually it was eliminated in all cheese batches after 4months of storage.

Stability of Viable Counts of Lactic Acid Bacteria during Storage of Goat Milk Soft Cheese

The use of goat milk is limited in Indonesia due to lack of good milking practices resulted in disliked goaty smell. One of the method to eliminate this off flavor is by processing the goat milk into soft cheese. The aim of this research was to study the stability of viable starter lactic acid bacteria cultures (Lactobacillus acidophilus FNCC-0051 and L. casei FNCC-0090) during storage of goat milk soft cheese. Three batches of goat milk soft cheeses were produced with different starter cultures L. acidophilus FNCC-0051 (5.0 x 106 cfu mL-1); L. casei FNCC-0090 (5.0 x 106 cfu mL-1); and the mixture of L. acidophilus FNCC-0051 (2.5 x 106 cfu mL-1) and L. casei FNCC-0090 (2.5 x 106 cfu mL-1). The goat milk cheeses had white color and soft. The viable lactic acid bacteria in the goat milk soft cheese reached 109 cfu g-1, which was stable for 8 weeks at 5 °C. Panelists liked goat milk soft cheeses, especially in term of its aroma. The specific aroma produced could mask the disliked goaty smell.

Current state of Portuguese dairy products from ovine and caprine milks

Most Portuguese cheeses possessing a Protected Designation of Origin (PDO) status are still manufactured following traditional methods – the majority of which use raw milk from small ruminants (mainly sheep), coagulated with a rennet from plant origin (wild thistle flowers) and without deliberate addition of any starter/nonstarter culture; the most famous and representative of these cheeses is Serra da Estrela. Most steps required for its manufacture are performed manually (or otherwise empirically), and are controlled by the cheesemaker herself based on own intuition and past experience – thus leading to a wide variability among dairy farms, and even from day to day cheese batches. This paper reviews and updates fundamental and applied knowledge encompassing technological, microbiological, chemical, organoleptic and textural features of traditional PDO cheeses, manufactured in Portugal from ovine and caprine (or both) milks.

Internal Transcribed Spacer as a Target to Assess Yeast Biodiversity in Italian Taleggio PDO Cheese

Three batches of soft smear-ripened Taleggio PDO cheese were made in Northern Italy during the summertime 2010. A total of 129 isolates cultured from cheese surface were examined by using PCR-based methods and sequencing of both the ITS1 region and D1 and D2 domains of the 26S rRNA gene. Sequence analysis of isolates brought to the identification of 6 species: Debaryomyces hansenii, Kluyveromyces lactis, Kluyveromyces marxianus, Yarrowia lipolytica, Pichia guilliermondii, and Torulaspora delbrueckii. Analysis of DNA directly extracted from 45 cheese surfaces permitted to detect 2 additional species Candida sake and Candida etchellsii. D. hansenii was predominant and widespread whereas the other yeast species were detected less frequently. To determine the relationships between yeast community and the environment, 39 isolates from wooden boxes used for dry salting of cheese were analyzed as well. Sequencing of ITS1 region allowed to identify D. hansenii, T. delbrueckii, and K. lactis. ITS1 multiple sequence alignments of D. hansenii detected in wooden boxes showed an in-del polymorphism at position 169. ITS1 secondary structures of yeasts were modeled to explore new applications of this region for molecular identification purposes. This study used molecular analysis to identify adventitious yeast population present in the surface of Taleggio smear-ripened cheese. D. hansenii was found predominant in pasteurized milk, in dry salting equipment, and in all cheese samples until the end of ripening.

Inulin and probiotic concentration effects on fatty and linoleic conjugated acids in cream cheeses

The aim of this study was to evaluate the changes in the lipid profile, especially in conjugated linoleic acid (CLA), in 12 cream cheese batches with different prebiotic (inulin) and probiotic (Bifidobacterium animalis and Lactobacillus acidophilus) concentrations stored for 45 days at 8 ± 0.5 °C and analyzed every 15 days. A Central Rotational Composite Design was used to establish the prebiotic and probiotic concentrations. The effect of the pre- and probiotic concentrations on CLA contents (mg g−1 of fat) was verified by plotting the response surface. The linear, quadratic, and interaction coefficients of the multiple linear regression for both prebiotic and probiotics were not significant (p > 0.05). No significant changes were observed neither in the lipid profile nor in the CLA content among the different batches, in which fatty acid composition and CLA concentrations were similar to the milk used in the preparation of the cream cheese and also to the control batch.

Real-time modeling of milk coagulation using in-line near infrared spectroscopy

This paper considers the extraction of meaningful information in real-time from near infrared (NIR) reflection measurements of coagulating milk. This information can be used for developing automatic cutting time determination. NIR spectra (1000–2500nm) recorded during coagulation were compressed by principal component analysis. Using component scores as a function of time, two models are proposed for describing the three milk coagulation processes: κ-casein proteolysis, micelle aggregation, and network formation. A model for the entire coagulation process and a composite model for the three individual coagulation processes were established and tested on 12 cheese batches. Both models fitted very well (R2>0.99) to the experimental NIR data. An algorithmic procedure is presented that is able to provide real-time parameter estimation for a semi-empirical model describing the kinetics of the milk coagulation processes as well as determining the transition times between the three different coagulation processes.

Microbial diversity of the traditional Iranian cheeses Lighvan and Koozeh, as revealed by polyphasic culturing and culture-independent approaches

The microbiota of two traditional Iranian cheeses (Lighvan and Koozeh) made of raw ewe’s milk or mixtures of ewe’s and goat’s milk without starter addition was explored by culture-independent and culture-dependent approaches. Three batches of Lighvan and one of Koozeh were subjected to culture-independent polymerase chain reaction (PCR)–denaturing gradient gel electrophoresis (DGGE) analysis and sequencing of dominant bands to assess the microbial structure and dynamics through manufacturing and ripening. In addition, culturing in elective media for lactic acid bacteria (M17, MRS and KAA), isolation of single colonies (n = 130), molecular identification by PCR-amplified ribosomal DNA restriction analysis and sequencing, and differentiation at the strain level by repetitive extragenic palindromic PCR was also performed. DGGE analysis showed that the dominant amplicons in all four cheese batches belonged to Lactococcus lactis and Streptococcus parauberis. In addition, Escherichia coli and Lactococcus garvieae were frequently identified in both Lighvan and Koozeh, while Streptococcus thermophilus was found occasionally. In contrast, Enterococcus faecium and Enterococcus faecalis were found to be dominant among the isolates in all batches. These species showed a high genetic diversity. The discrepancy between culturing and DGGE results suggested that dominant populations were in a nonrecoverable state in the used media. This reinforces the idea that culture-dependent and culture-independent techniques provide complementary data, ultimately affording a better description of cheese ecosystems. These data could be of help in the selection of commercial starters for industrial-scale manufacture of Lighvan and Koozeh cheeses using pasteurised milk. Alternatively, microbial analysis would allow the selection of appropriate strains for designing of specific starters for traditional cheese manufacture.

Microbiological changes in Lighvan cheese throughout its manufacture and ripening

The aim of this research was to monitor the microbiological changes throughout the manufacture and ripening of Lighvan cheese. In summer 2009, ten independent batches of cheese were manufactured by experienced workers without any intervention by the researcher. Duplicate samples of raw milk, coagulum and 0, 15, 30, 60 and 90 days old cheese were analyzed. The main groups, such as mesophilic Lactococci, thermophilicLactococci, mesophilic Lactobacilli, thermophilic Lactobacilli, Enterococci, and the total aerobic count reached its highest levels during the first 15 days and then declined approximately 2 to 3 log units until the end of ripening. The number of coliforms,Micrococci, and Staphylococcus increased at early phases of manufacturing and at the end of the manufacturing and ripening phase they showed a falling trend. The number of yeasts throughout this phase decreased at the rate of 3 log units. Generally, we may claim that in ripening Lighvan cheese a large number of different microbes were involved and its hygienic matters call for more attention. Key words: Lighvan cheese, microbiological changes, manufacturing, ripening.

Evaluation of quality of Coalho cheese produced with endogenous Lactococcus spp.

PurposeThe objective of this study is to evaluate the quality of Coalho cheese produced using two different strains of Lactococcus spp. that were isolated from artisanal Coalho cheese in Bahia, Brazil.Design/methodology/approachThree different batches of cheeses were produced using lactic acid Lactococcus spp. strains named “LA‐02”, “RE‐02” and “Blend” (LA‐02 plus RE‐02). To study the quality of these products the paper uses quantitative descriptive analysis (QDA), a test of acceptability and an analysis of physical‐chemical parameters.FindingsFor the flavor attribute, the highest acceptabilities were for LA‐02 (7.38) and Blend (6.92). The panelists found that 13 attributes were important to describe Coalho cheese. The Blend cheese was characterized by its yellow color, hardness, consistency, chewiness, typical Coalho cheese aroma and flavor. The LA‐02 cheese was characterized by its acid flavor, homogeneity and softness. All the samples analyzed showed values of moisture and fat that were in line with Brazilian legislation.Practical implicationsCoalho cheese is a typical Brazilian artisanal cheese that is normally produced with raw milk, even though legislation does not allow this. Pasteurization of the milk used to produce cheeses guarantees the microbiological safety of the product and, in this case, the cheese needs the addition of lactic acid bacteria in order to improve the sensorial quality and to give typical characteristics.Originality/valueCoalho cheese, as produced in the artisanal form, is widely appreciated for its sensorial characteristics. The Coalho cheese proposed in this research retains the typical sensory characteristics by using different strains of Lactococcus spp. that were isolated from artisanal Coalho cheese but according to the specification of good manufacturing practices (GMP).

Free fatty acid composition and sensory characteristics of rg cheese

Two batch of Orgu cheese, a semi-hard, white, brine ripened Turkish traditional cheeses, from raw and pasteurized cow’s milk were produced. Streptococcus thermophilus and Lactobacillus bulgaricus were used as starter culture for pasteurized milk. The main FFA observed in the raw and pasteurized milk Orgu cheeses during ripening were palmitic, oleic, myristic, steric and capric acids, representing together approximately 82% of total FFA content. Butyric (C4), caproic (C6), caprylic (C8), capric (C10) and lauric (C12) acids contents of RA and PA milk Orgu cheeses increased during ripening. However, myristic (C14), palmitic (C16), stearic (C18), oleic (C18:1) and linoleic (C18:2) acids contents of pasteurized milk cheese remained constant (P>0.05). The results revealed that pasteurization of milk has a restricted level of lipolysis throughout ripening. Appearance and body-texture properites of PMC were not significantly inferior to that of RMC. However, PMC failed to reach the expected quality of odor and flavour level. Key words: Traditional cheese, lypolisis, free fatty acids.

Composition, yield, and functionality of reduced-fat Oaxaca cheese: Effects of using skim milk or a dry milk protein concentrate

The effect of adding either skim milk or a commercial dry milk protein concentrate (MPC) to whole milk on the composition, yield, and functional properties of Mexican Oaxaca cheese were investigated. Five batches of Oaxaca cheeses were produced. One batch (the control) was produced from whole milk containing 3.5% fat and 9% nonfat solids (SNF). Two batches were produced from milk standardized with skim milk to 2.7 and 1.8% fat, maintaining the SNF content at 9%. In the other 2 batches, an MPC (40% protein content) was used to standardize the milk to a SNF content of 10 and 11%, maintaining the milk fat content at 3.5%. The use of either skim milk or MPC caused a significant decrease in the fat percentage in cheese. The use of skim milk or MPC showed a nonsignificant tendency to lower total solids and fat recoveries in cheese. Actual, dry matter, and moisture-adjusted cheese yields significantly decreased with skim milk addition, but increased with MPC addition. However, normalized yields adjusted to milk fat and protein reference levels did not show significant differences between treatments. Considering skim milk-added and control cheeses, actual yield increased with cheese milk fat content at a rate of 1.34 kg/kg of fat (R=0.88). In addition, cheese milk fat and SNF:fat ratio proved to be strong individual predictors of cheese moisture-adjusted yield (r2 ≈ 0.90). Taking into account the results obtained from control and MPC-added cheeses, a 2.0-kg cheese yield increase rate per kg of milk MPC protein was observed (R=0.89), with TS and SNF being the strongest predictors for moisture adjusted yield (r2 ≈ 0.77). Reduced-fat Oaxaca cheese functionality differed from that of controls. In unmelted reduced-fat cheeses, hardness and springiness increased. In melted reduced-fat cheeses, meltability and free oil increased, but stretchability decreased. These changes were related to differences in cheese composition, mainly fat in dry matter and calcium in SNF.

Assessment of Microbial Populations Dynamics in a Blue Cheese by Culturing and Denaturing Gradient Gel Electrophoresis

The composition and development of microbial population during the manufacture and ripening of two batches of a blue-veined cheese was examined by culturing and polymerase chain reaction (PCR) denaturing gradient gel electrophoresis (DGGE) (PCR-DGGE). Nine selective and/or differential media were used to track the cultivable populations of total and indicator microbial groups. For PCR-DGGE, the V3 hyper variable region of the bacterial 16S rRNA gene and the eukaryotic D1 domain of 28S rDNA were amplified with universal primers, specific for prokaryotes and eukaryotes, respectively. Similarities and differences between the results obtained by the culturing and the molecular method were recorded for some populations. Culturing analysis allows minority microbial groups (coliforms, staphylococci) to be monitored, although in this study PCR-DGGE identified a population of Streptococcus thermophilus that went undetected by culturing. These results show that the characterization of the microbial populations interacting and evolving during the cheese-making process is improved by combining culturing and molecular methods.

Microbial stability and safety of traditional Greek Graviera cheese: characterization of the lactic acid bacterial flora and culture-independent detection of bacteriocin genes in the ripened cheeses and their microbial consortia.

The microflora of four batches of traditional Greek Graviera cheese was studied at 5 weeks of ripening, and 200 lactic acid bacteria (LAB) isolates were phenotypically characterized and screened for antilisterial bacteriocins. The cheeses were also analyzed for organic acids by high-performance liquid chromatography and for the potential presence of 25 known LAB bacteriocin genes directly in cheese and their microbial consortia by PCR. All batches were safe according to the European Union regulatory criteria for Listeria monocytogenes, Salmonella, enterobacteria, and coagulase-positive staphylococci. The cheese flora was dominated by nonstarter Lactobacillus casei/paracasei (67.5%) and Lactobacillus plantarum (16.3%) strains, whereas few Streptococcus thermophilus (3.8%), Lactococcus lactis subsp. lactis (0.6%), and Leuconostoc (1.9%) organisms were present. Enterococcus faecium (9.4%) and Enterococcus durans (0.6%) were isolated among the dominant LAB from two batches; however, enterococci were present in all batches at 10- to 100-fold lower populations than mesophilic lactobacilli. Sixteen E. faecium isolates produced antilisterial enterocins. In accordance, enterocin B gene was detectable in all cheeses and enterocin P gene was present in one cheese, whereas the consortia of all cheeses contained at least two of the enterocin A, B, P, 31, L50A, and L50B genes. Plantaricin A gene was also amplified from all cheeses. Mean concentrations of lactic, acetic, citric, and propionic acids in the ripened cheeses exceeded 1.5% in total, of which approximately 0.9% was lactate. Thus, organic acid contents constitute an important hurdle factor for inhibiting growth of pathogens in traditional Graviera cheese products, with LAB bacteriocins, mainly enterocins, potentially contributing to increased cheese safety.

The influence of chemical composition of milk on yield of semi-hard cheese

The aim of paper was to examine the impact of the milk quality on yield of semi-hard naturally dried cheese, produced in cheese plant factory ZZ 'Cijevna' in Podgorica. Tests were conducted on 6 samples of bulk milk of cows and 6 productive batch of cheese. Chemical tests of the bulk milk have been done on the device MilcoScan 4000, and the determination content dry matter of whey and dry matter of cheese on the device MilcoScan FT 120. Theoretical yield of cheese was determined in two ways: 1) based on the content of fat and protein content in milk and 2) based on dry matter content of milk, dry matter of whey and dry matter of cheese. Actual yield of cheese is determined on the base of the total amount of cheese obtained after pressing and the amount of wasted milk. The average value for the fat content in the examined milk amounted to 3.79%, protein 3.24%, 4.26% lactose and dry matter content without fat 8.24%. The average value for the theoretical cheese yield by first method was 10.65% and by second method 9,30%. The average of actual cheese yield amounted to 11.26%. We found a very high positive correlation between content of fat in milk and actual cheese yield (0.929032) and mean positive correlation between content of protein in milk and actual cheese yield (0.613141), content of lactose in milk and actual cheese yield (0.651317) and between dry matter content in milk and actual cheese yield (0.651956).

Candida cabralensis sp. nov., a yeast species isolated from traditional Spanish blue-veined Cabrales cheese

Three yeast strains, 1AD8(T), 3AD15 and 3AD23, belonging to a previously unknown yeast species were isolated from two independent batches of the Spanish blue-veined Cabrales cheese, a traditional cheese manufactured without the addition of starter and mould cultures. Physiological characterization revealed that the unknown yeast is not fermentative and does not assimilate lactose; rather it assimilates dl-lactic acid and ethanol, major end products of lactic acid bacteria metabolism in cheese. The novel yeast is anamorphic. Phylogenetic tree reconstruction based on nucleotide sequence comparison of the D1/D2 region of the 26S rRNA gene showed that Pichia terricola and Pichia fermentans are the closest relatives of the unknown species. The name Candida cabralensis sp. nov. is proposed, and the isolate 1AD8(T) (=CECT 13027(T) =CBS 11679(T)) is the type strain of this novel taxon.

Composition, functional properties and sensory characteristics of Mozzarella cheese manufactured from different somatic cell counts in milk

In the present study, composition, functional properties and sensory characteristics of Mozzarella cheese produced from milk with somatic cell counts (SCC) at low (&lt;200,000 cells/mL), intermediate (≈400,000 cells/mL) and high (&gt;800,000 cells/mL) levels were investigated. Three batches of cheese were produced for each SCC category. The cheeses were vacuum packed in plastic bags and analysed after 2, 9, 16, 23 and 30 days of storage at 4ºC. SCC level did not affect the moisture, fat, total protein and ash content, mesophilic and psychrotrophic bacteria, and sensory parameters of Mozzarella cheese. However, meltability increased in cheese manufactured from high SCC milk. Results indicated that raw milk used to produce Mozzarella cheese should not contain high SCC (&gt;800,000 cells/mL) in order to avoid changes in the functional properties of the Mozzarella cheese.

Important genetic diversity revealed by inter-LTR PCR fingerprinting ofKluyveromyces marxianusandDebaryomyces hanseniistrains from French traditional cheeses

The genetic diversity of two major yeast species found in cheese, Debaryomyces hansenii and Kluyveromyces marxianus, was analyzed within the yeast flora in French traditional cheesemaking. Based on the amplification of sequences separating long terminal repeat (LTR) retrotransposon sequences, a molecular typing method was developed for D. hansenii and K. marxianus. This method was applied to a total of 56 D. hansenii strains and 61 K. marxianus strains, mostly isolated during fermentation and ripening of traditional cheese from Normandy and Haute-Savoie (French Alps) regions. A total of 32 and 43 robust profiles were obtained for D. hansenii and K. marxianus, respectively. Cluster analysis confirmed the large genetic diversity already shown for D. hansenii and revealed an even larger diversity for K. marxianus. After its use with Saccharomyces cerevisiae, the inter-LTR PCR proved to be efficient to discriminate between strains of the two species, D. hansenii and K. marxianus, isolated from the same ecological niches, confirming the high intra-specific variability of species found in cheese. This strain typing could not correlate the analyzed strains with their origin, would it be the cheese type, the cheese-making facility or the cheese batch, showing a high discrimination power. The method described here will provide a fast and reliable tool for the biodiversity study of these two major cheese yeasts.

Outbreak of Salmonella enterica serotype Muenster infections associated with goat's cheese, France, March 2008

Salmonella enterica serotype Muenster (hereafter referred to as S. Muenster) is rare in France and in Europe. In France, a nationwide outbreak of gastrointestinal illness due to S. Muenster occurred during March and April 2008. Twenty-five laboratory-confirmed cases of S. Muenster were documented by telephone using a trawling questionnaire. Four patients were admitted to hospital and no death was recorded. Among the 21 interviewed cases, 16 reported consumption of goat's cheese in the days prior to symptoms. The investigation incriminated goat's cheese from producer X as being the most likely source of the outbreak. S. Muenster was isolated from both cases and the incriminated goat's cheese. The pulsed-field gel electrophoresis profiles of the food isolates of producer X and the isolates from cases were indistinguishable. Following the withdrawal of the contaminated batch of cheese, the number of cases decreased to its usual level. To our knowledge, this is the first published outbreak of S. Muenster associated with food consumption in Europe.

Minas-type fresh cheese developed from buffalo milk with addition of L. acidophilus

Effective incorporation of a probiotic into foods requires the culture to remain viable all along processing and storage, without adverse alterations to sensory characteristics. The objective of this work was developing Minas-type fresh cheese with probiotic properties from buffalo milk. Four batches of Minas-type fresh cheese were prepared using buffalo milk: batch T1 in which neither culture nor lactic acid added; batch T3 in which only lactic acid added; batches T2 and T4 , both added of Lactobacillus acidophilus LAC 4, but T4 was also acidified. Resulting cheeses were evaluated for probiotic culture stability, texture profile, sensory acceptance, and changes in pH. The T4 probiotic cheese presented hardness, gumminess, and chewiness significantly lower than the other treatments. However, values for springiness and cohesiveness did not differ between all cheeses, and no sensory differences (p &gt; 0.05) were found between treatments for texture, taste, and overall acceptance. The addition of probiotic to the acidified cheese (T4) yielded best aroma. The populations of L. acidophilus were greater than 10(6) CFU g-1 after 28 days of storage all products. Minas-type fresh cheese from buffalo milk is a suitable food for the delivery of L. acidophilus, since the culture remained viable during the shelf life of the products and did not negative affect analysed parameters.

Evaluation of Chemical Composition and Yield of Mozzarella Cheese Using Two Different Methods of Processing

Two Mozzarella cheese making methods, Kosikowski (1982) and the modified method practiced by Khartoum Dairy Products Company (KDPC) were evaluated for their efficiencies in term of chemical composition and yield. In a comparison study; using fresh whole cow's milk; two experiments were conducted. In experiment one the cheese was manufactured according to the method described by Kosikowski (1982). While in experiment two the modified method practiced in Khartoum Dairy Product Company (KDPC) Ltd. was used. In Kosikowski (1982) method, pasteurized milk was used. Starter culture (0.5%) was added and renneting at 32.2°C, cooling and whey drainage overnight; were practiced in this method. In the modified method, raw milk was used. Starter culture (1%) and rennet were added at 38.5°C. The results showed that, fresh Mozzarella cheese; using Kosikowski (1982) method had the following means composition, fat 27.25%±0.82; protein 20.06%±0.65; total solids 51.42% ±1.32; moisture 48.59% ± 1.32; titratable acidity 066% ± 0.02; ash 2.25±0.07%; lactose 1.59±1.35% and yield 13.2%. However, the mean compositions in modified method were: fat 25.71%±2.30; protein 23.33%2.1; total solids 54.52%±2.84; moisture 45.48%±2.85; titratable acidity 0.58%0.09; ash 2.38%±0.41; lactose 2.64% ±0.73 and yield 11.65%. Cheese batches in experiment two showed a decrease in fat, protein and ash content after storage for seven days at -18 C and 4 C. o o