JOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 2 2000
MANUELA E. PINTADO
The effects of modified atmosphere packaging on growth of adventitious microorganisms in Portuguese whey cheese (Requeijão) were studied following a response surface methodology using storage time (2, 6, 10 and 15 days), storage temperature (4, 12 and 18C) and fraction of CO2 in the overhead gaseous mixture also containing nitrogen (0, 50 and 100%) as manipulated variables. the viable numbers of Enterobacteriacea, staphylococci, yeasts and spore-forming bacteria in the experimental whey cheeses did not increase within 15 days when storage was at 4C under 100% CO2; those of enterococci increased significantly after 6 days under similar conditions, and a similar inhibiting effect was observed against Bacillus, pseudomonads, lactobacilli and streptococci. It was observed that 100% N2 at 4C was able to completely inhibit growth of staphylococci, lactobacilli and Bacillus for 2 days. the loci (and the nature) of the optima in terms of manipulated variables were obtained for all microbial groups studied. No true overall minimum was found, but storage conditions preset at 4C and 100% CO2 led to a 15 day extension of the shelf-life of Requeijão. [source]

PERCEPTION OF CHEESE: A COMPARISON OF QUALITY SCORING, DESCRIPTIVE ANALYSIS AND CONSUMER RESPONSES

JOURNAL OF FOOD QUALITY, Issue 4 2005
MARGRETHE HERSLETH
ABSTRACT The main objective of this study was to study perception of cheeses by comparing quality scores from expert assessors, descriptive profiling data from selected assessors and consumer responses. Twelve cheeses were evaluated by expert assessors and profiled by selected assessors. Five cheeses were selected for consumer testing and rated for hedonic liking, plus flavor intensity and degree of soft/firm texture. Analysis of variance and multivariate analyses of the data showed that the expert assessors scores for consistency, flavor and overall quality correlated positively with descriptive profiling attributes as mature flavor/odor, firmness, graininess and dryness of the cheeses. Preference mapping showed an even distribution of the consumers in the sensory map, which indicated different sensory segments. Some consumers preferred a firm cheese with a mild, mature flavor and others preferred a doughy cheese with more acid, fermented flavor. The expert assessors represented the preferences of the first group in their scoring procedure. [source]

SENSORY CHARACTERISTICS OF EZINE CHEESE

JOURNAL OF SENSORY STUDIES, Issue 1 2007
YONCA KARAGUL-YUCEER
ABSTRACT Ezine cheese is a full-fat, white pickled cheese ripened in tinplate containers. A mixture of milks from goat, sheep and cow is used to make Ezine cheese. It has its own characteristic taste and aroma that differ from other white cheeses. In this study, the chemical composition and sensory attributes of Ezine cheese were characterized. A descriptive sensory evaluation technique was used to determine flavor and texture characteristics. Representative Ezine cheeses (22) were provided by local producers. A highly trained (n = 9) panel generated the descriptive terms and identified the references. Fourteen flavors and 10 texture terms were developed to describe Ezine cheese flavor and texture. Some characteristic flavor and taste descriptors for Ezine cheese were free fatty acids, cooked, creamy, whey-like, goaty, salty and sour. Cheese texture was evaluated using hand, mouth and residual techniques. Texture analysis indicated that Ezine cheese had soft and semi-hard texture properties. In general, most of the Ezine cheeses showed similarities in terms of hand firmness, mouth firmness, fracturability and number of particles attributes. [source]

SENSORY PROFILE OF FLAVOR AND ODOR CHARACTERISTICS IN RONCAL CHEESE MADE FROM RAW EWE'S MILK

JOURNAL OF SENSORY STUDIES, Issue 5 2002
PATRICIA LARRÁYOZ
ABSTRACT Roncal cheese is made from raw ovine milk and is regulated by an Appellation of Origin. This cheese variety is quite popular with consumers because of its special properties, which are unlike those of other ewe's-milk cheeses. To date there have been no studies aimed at characterizing the flavor and odor attributes of Roncal cheese. To remedy this situation, sensory analysis has been performed using Roncal cheese samples collected from artisanal and industrial cheese-making establishments. The cheeses were made at three different times of year (winter, spring, and summer) and were ripened for four or eight months. Sensory descriptors were generated, and after discussion suitable descriptors for describing and discriminating among Roncal cheese samples were selected by multivariate analysis. In all, 19 descriptors were employed, namely: odor: cream, meat broth, olive, toffee, liquid caramel, toasted, acetic acid, sweat, acidified milk, ammonia, leather, stable straw, wool, and odor intensity. flavor: characteristic flavor, acetic acid, sweat, butyric acid, and flavor intensity. [source]

CROSS VALIDATION OF A SENSORY LANGUAGE FOR CHEDDAR CHEESE

JOURNAL OF SENSORY STUDIES, Issue 3 2002
M.A. DRAKE
ABSTRACT Communication and replication of sensory data from different sites are important to track progress on fundamental research issues and to ensure that research efforts are not duplicated. A uniform anchored Cheddar cheese sensory language has previously been identified and refined. The objective of this study was to demonstrate application of the defined sensory language for Cheddar cheese for communication between sensory panels at three different sites. The defined and referenced sensory language for Cheddar cheese was disseminated to panel leaders at the three sites and sensory panels (n , 8) were trained for 40 to 80 h at each site. Ten forty-pound blocks of Cheddar cheese representing different ages were collected and evaluated by the panels. Cheeses were differentiated by the three panels by univariate and multivariate analysis (P<0.05). Cheeses were differentiated by the three panels in a similar manner. Results indicate that it is possible to calibrate panels using a standardized defined sensory language. [source]

EFFECT OF FREEZING AND FROZEN STORAGE ON THE SENSORIAL CHARACTERISTICS OF LOS PEDROCHES, A SPANISH EWE CHEESE

JOURNAL OF SENSORY STUDIES, Issue 3 2000
L. TEJADA
ABSTRACT The aim of the present work was to study the sensorial characteristics of Los Pedroches cheese after freezing, monitoring the effects of the speed and time of frozen storage. Changes were observed in the hardness, creaminess and eyes of cheeses after 3-months frozen storage. The paste hardened, becoming less creamy, and the number and size of the eyes decreased substantially. However, these attributes remained unchanged during storage periods of up to 9 months. Odor, flavor intensity, acidity and grainy were modified as a consequence of frozen storage. The speed of the freezing process only affected the grainy of the cheese; this was greater in slowly-frozen cheeses. [source]

RHEOLOGICAL PROPERTIES OF MOZZARELLA CHEESE DETERMINED BY CREEP/RECOVERY TESTS: EFFECT OF SAMPLING DIRECTION, TEST TEMPERATURE AND RIPENING TIME

JOURNAL OF TEXTURE STUDIES, Issue 3 2009
MARÍA LAURA OLIVARES
ABSTRACT The viscoelastic properties of mozzarella cheese using a creep/recovery test considering different sampling directions (parallel and perpendicular to protein fiber orientation), test temperatures (20, 30 and 40C) and ripening times (1, 8, 15, 29 and 36 days) were studied. Creep data were interpreted by a Burger model of four parameters. A semiempirical approach was proposed to obtain the contribution of each main compliance to the total deformation of the system. Creep tests at different temperatures allowed gaining a better understanding of changes that occur in the cheese matrix during heating and ripening. Sampling direction did not affect any of the parameters studied. Finally, it was clearly observed that cheese matrix behaves as a quite different physicochemical system depending on temperature. Therefore, it is recommended to carry out the rheological tests at different temperatures to evaluate appropriately the viscoelastic properties of mozzarella cheese. PRACTICAL APPLICATIONS Mozzarella cheese must have certain characteristics to be used on pizzas and on other prepared foods that use the cheese in melted state. The protein chains in the mozzarella curds coalesce into large strands that are oriented in the direction of stretching. For this reason, mozzarella cheese has an anisotropic structure. Therefore, it is relevant to determine the effect of protein fiber orientation on the rheological properties. Valuable information may be obtained through the creep/recovery test of mozzarella cheese samples to study its rheological properties and to explain molecular mechanisms that occur during ripening or melting processes considering sampling direction. [source]

DEVELOPMENT OF A SOY-BASED CREAM CHEESE

JOURNAL OF TEXTURE STUDIES, Issue 6 2008
MUSFIRAH ZULKURNAIN
ABSTRACT Various amounts of blended tofu, oil, salt, carrageenan, pectin and maltodextrin were used to develop soy cream cheese products that were trans fat free, with texture properties similar to those of commercial dairy cream cheese. Response surface methodology predicted three formulations with similar spreadability value of that obtained from commercial cheese. Carrageenan and salt were useful to impart the desired firmness, while maltodextrin provided body to the product. Pectin introduced viscous behavior to the final texture but was proven useful in preventing syneresis. Rheological study at 25 and 4C manifested that, although the developed products mimicked the texture of the commercial sample, they had less elasticity. Chemical analysis revealed that the soy cream cheeses had lower fat and higher protein and fiber contents than the commercial sample. They were also stable against syneresis and oil separation over storage of 20 days. PRACTICAL APPLICATIONS The production of soy-based products as alternatives to dairy products has attracted much attention recently. In addition to their lactose-free and reduced fat content, soy-based products are also a good source of protein. There has yet to be any published data on the development of a soy-derivative cream cheese. This paper emphasizes the rheological development of soy cream cheeses in the presence of food hydrocolloids. Their main and interaction effects on texture properties were assessed to mimic those of dairy cream cheese. A comprehensive and systematic approach of formulating the soy cream cheeses was applied by using response surface methodology. In addition, the chemical and nutritional properties of the products were also evaluated and compared with those of the commercial dairy counterpart. [source]

CHARACTERIZATION OF THE NONLINEAR VISCOELASTIC CONSTITUTIVE PROPERTIES OF MILD CHEDDAR CHEESE FROM INDENTATION TESTS

JOURNAL OF TEXTURE STUDIES, Issue 5-6 2005
S.M. GOH
ABSTRACT A methodology to convert the indentation force,displacement response into the stress,strain properties of nonlinear viscoelastic materials was evaluated. Mild cheddar cheese was used as the test material, and indentation tests were performed using two spherical indenters of different sizes. The indentation tests were performed at different speeds, and the corresponding force,displacement responses were fitted with an analytical solution to obtain the time-dependent constants and the instantaneous force,displacement response. An inverse analysis based on the finite element method was performed to obtain the strain-dependent constants from the instantaneous force,displacement response. The predictions of the viscoelastic stress,strain properties from the indentation tests were compared to independent measurements through uniaxial compression tests, and a reasonable agreement was obtained. [source]

FAT REPLACERS IN LOW-FAT MEXICAN MANCHEGO CHEESE

JOURNAL OF TEXTURE STUDIES, Issue 1 2001
C. LOBATO-CALLEROS
Low-fat Manchego cheeses (15 g fat/L milk) were prepared with three commercial fat replacers consisting of low methoxyl pectin (LMP), whey protein concentrate (WPC) and microparticulated whey protein (MWP). A low-fat cheese (15 g fat/L milk) without added fat replacer and a full-fat cheese (30 g fat/L milk) were prepared as controls. Cheeses were matured thirty days prior to instrumental texture profile analysis, microstructure analysis, and discriminative sensory evaluation. Scanning electron micrographs showed that the low-fat cheeses incorporating the LMP and WPC fat replacers lost the compact and dense protein matrix characteristic of the low-fat control cheese and exhibited hardness, springiness, cohesiveness and chewiness similar to the full-fat control cheese. No significant difference was found in the sensory characteristics between the full-fat control cheese and the cheese incorporating WPC. [source]

VISCOELASTIC PROPERTIES OF WHITE FRESH CHEESE FILLED WITH SODIUM CASEINATE

JOURNAL OF TEXTURE STUDIES, Issue 4 2000
C. LOBATO-CALLEROS
ABSTRACT The yield, moisture loss and viscoelastic properties of white fresh cheeses containing sodium caseinate were determined and compared to those of a reference cheese without sodium caseinate. Added sodium caseinate resulted in higher cheese yields and lower moisture losses during aging. Creep compliance tests were performed on the cheeses using a parallel plate viscoelastometer. Multiple regression analysis of the experimental data provided first order models that explain the variation of most of the viscoelastic parameters of the white fresh cheeses in terms of sodium caseinate level, moisture content, aging and pH. The instantaneous elastic compliance and the Newtonian viscosity increased with moisture content and pH, respectively. The retarded elastic compliances increased and the first retardation time decreased during aging. The influence of sodium caseinate on most of the viscoelastic parameters was significant. [source]

BIOGENIC AMINE CONTENT OF SOME TURKISH CHEESES

JOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 4 2002
FÜGEN DURLU-ÖZKAYA
Biogenic amines in ten samples of Ka,ar (aged), five samples of Ka,ar (fresh), four samples of Mihaliç, nine samples of Van Otlu (herbed), nine samples of Örgü, nine samples of Urfa and six samples of Civil cheeses were obtained from local supermarkets of Ankara. Tryptamine (TRY), phenylethylamine (PHA), putrescine (PUT), cadaverine (CAD), histamine (HIT), tyramine (TYA), spermine (SPM) and spermidine (SPD) contents of Turkish cheese samples were screened by high performance liquid chromatography (HPLC). PUT, CAD, HIT, TYA and SPD were the predominant biogenic amines in maturated Ka,ar (aged), vacuum-packed Ka,ar (fresh), Mihaliç, Otlu (herbed) and Örgü cheeses. PHA, CAD, TYA and SPD were the predominant biogenic amines in Urfa cheese samples. Civil cheeses were found to contain the highest HIT and TYA content with an average of 94.76 mg/100 g and 138.16 mg/100 g, respectively, much higher than the toxic dose. HIT level of Mihaliç cheeses were also higher than the accepted limit. The concentration of amines in all other cheeses was much lower than the toxic dose limits. [source]

RHEOLOGY AND TEXTURE OF COMMERCIAL QUESO FRESCO CHEESES MADE FROM RAW AND PASTEURIZED MILK

JOURNAL OF FOOD QUALITY, Issue 2010
MICHAEL H. TUNICK
ABSTRACT Queso Frescos made in Mexico from raw milk (RM) were compared with cheeses made in Mexico and the U.S.A. from pasteurized milk (PM) to determine textural and rheological differences. RM cheese, considered the ideal Queso Fresco, contained more moisture than PM cheeses, displayed higher cohesiveness and shear strain and exhibited lower hardness and shear stress. The U.S.-made cheeses were harder and more brittle and crumbly than the Mexican cheeses. The shear stress decreased as fat content increased in all samples, and the shear strain decreased as the pH increased in the Mexican cheeses. An understanding of the differences between the RM and PM versions should allow cheese makers to adjust manufacturing procedures so that PM Queso Fresco cheeses will meet consumer expectations. PRACTICAL APPLICATIONS Hispanic cheeses such as Queso Fresco are gaining in popularity in the U.S.A. The milk for making Queso Fresco in the U.S.A. must be pasteurized, and the resulting cheese is perceived by some consumers to be inferior in flavor and texture to the traditional variety made from raw milk. Queso Fresco samples made in Mexico from both kinds of milk and made in the U.S.A. from pasteurized milk were analyzed to see if there were differences in texture, structure, and the ability to twist and break pieces of the cheese. The cheeses made in the U.S.A. contained less moisture and were too hard, crumbly, and brittle when compared to the raw milk cheeses. The differences observed should enable U.S. companies to make Queso Fresco with properties close to those of the raw milk variety. [source]

FATTY ACID COMPOSITION AND CONJUGATED LINOLEIC ACID CONTENT OF COW AND GOAT CHEESES FROM NORTHWEST ARGENTINA

JOURNAL OF FOOD QUALITY, Issue 3 2009
CARINA P. VAN NIEUWENHOVE
ABSTRACT In this study, we evaluated chemical characteristics, fatty acid composition and conjugated linoleic acid (CLA) content of cow and goat cheeses from Northwest Argentina. Similar chemical and fatty acid composition were determined in milk and cheese of both species. Palmitic, oleic and myristic acids were the most abundant fatty acids in dairy products. CLA level averaged 0.85 and 0.96 in milk and 0.76 and 1.04 g/100 g of fatty acids in cheese of cow and goat, respectively. Cis -9,trans -11 was the major isomer present in both species. Significant differences in CLA desaturase activity were observed, showing a value of 0.068 and 0.064 in milk, and 0.077 and 0.071 in cheese of cow and goats, respectively. Good nutritional properties were determined for cheeses of both species, which are fed on natural pasture during spring and summer seasons. Goat's cheese represents a higher source of CLA for human consumers than cow's cheese, offering from 156.6 to 222.6 mg/ 100 g of sample. PRACTICAL APPLICATIONS The present work shows the fatty acid composition and chemical characteristics of two fresh cheeses manufactured with cow and goat milk. Animals were fed on natural pasture during summer and spring seasons. It is known that pasture increases conjugated linoleic acid (CLA) concentration in milk fat, and the content in cheese is directly related to it. The CLA content of dairy products for the human consumers was analyzed, showing goat cheese with high polyunsaturated fatty acid content, including CLA. Cow and goat fresh cheese offer CLA as many ripening products of different countries, as cheddar or hard cheeses. Lipid composition of food is related to many illnesses, but some compounds are beneficial to human health. The main sources of CLA are milk and cheeses, and in Northwest of Argentina, no data are reported about it, where artisanal cheeses are consumed by the population. Therefore, the atherogenicity index was determined as well. [source]

HYGIENIC PARAMETERS, TOXINS AND PATHOGEN OCCURRENCE IN RAW MILK CHEESES

JOURNAL OF FOOD SAFETY, Issue 3 2002
K. DE REU
ABSTRACT In total, 71 samples of retail raw milk cheeses produced or imported in Belgium and samples of Belgian farmhouse cheeses were examined for cotiforms, ,-glucuronidase positive Escherichia coli, Escherichia coli O157, Staphylococcus aureus, Salmonella spp., Listeria spp. and Listeria monocytogenes. The presence of staphylococcal enterotoxins was investigated on samples with S. aureus counts higher than 103 cfu/g. The incidence of coliforms, ,-glucuronidase positive E. coli and S. aureus was higher in soft than in blue veined, semi-hard, hard and fresh cheeses. Four mold-ripened soft cheeses were positive for E. coli O157. One of the 4 cheeses was positive for verotoxin VT2. Staphylococcal enterotoxins were detected in 1 soft redsmear cheese, which was positive for L. monocytogenes. L. monocytogenes was also detected in one fresh cheese. Salmonella was not detected in any of the 71 raw milk cheeses. [source]

SIMPLIFIED LEXICON TO DESCRIBE FLAVOR CHARACTERISTICS OF WESTERN EUROPEAN CHEESES

JOURNAL OF SENSORY STUDIES, Issue 4 2008
MARTIN TALAVERA-BIANCHI
ABSTRACT Many researchers have developed useful lexicons to describe flavor characteristics of different cheeses. The objectives of this study were to determine if the terminology established in previous studies was adequate to evaluate a wide range of European cheeses, and to determine if a simplified "general" lexicon can be developed for the description of cheese. A descriptive panel evaluated the flavor of 65 western European cheeses that varied in region produced, milk source, maturation time and processing method. The panel reviewed previously published cheese attributes, definitions and references prior to beginning the testing. During testing, the panel detected and added new descriptors and eliminated terms which did not appear in any of the cheeses. Data inspection, in addition to factor analysis, suggests that 25 attributes are needed to explain the common flavor characteristics found in cheese. However, 19 additional attributes may be used occasionally to describe targeted specific flavor characteristics. PRACTICAL APPLICATIONS The flavor of cheese, an increasingly popular food, is critical to producers and consumers. A large number of sensory descriptors can be used to describe flavor characteristics of cheese. The research indicates a lexicon with a reduced number of terms that can be used to describe most general flavor characteristics. Other characteristics are needed occasionally to describe specific characteristics of some cheeses. [source]

SENSORY AND INSTRUMENTAL EVALUATIONS OF TEXTURE IN CHEESES MADE FROM OVINE MILKS WITH DIFFERING FAT CONTENTS

JOURNAL OF SENSORY STUDIES, Issue 2 2002
A. IRIGOYEN
ABSTRACT The present study considers the influence of reducing the fat content of ovine milk on the sensory and instrumental texture characteristics of the resulting cheeses. Three manufacturing runs were performed. In each run three cheese batches were manufactured using milks with differing percentage fat contents (8%, 4%, and 2% fat). Analysis of cheese samples was performed at 60, 90, and 120 days of ripening. The instrumental method used to evaluate cheese texture was uniaxial compression at constant speed, taking readings of stress, strain, and modulus of elasticity (E). Statisticalanalysis revealed differences forboth the differentfat contents and the ripening times considered. Instrumental parameter values increased with lower cheese fat contents; with a 20% reduction in the fat to dry matter content from full-fat to reduced-fat cheeses, resulting in a 35% increase in maximum stress and in the slope of the stress-strain curve at the end of ripening. The greatest sensory differences between samples were recorded for firmness. [source]

CHANGES IN CHEMICAL, SENSORY AND RHEOLOGICAL CHARACTERISTICS OF MANCHEGO CHEESES DURING RIPENING

JOURNAL OF SENSORY STUDIES, Issue 4 2001
MIGUEL ANGEL GONZÁLEZ-VIÑAS
ABSTRACT Manchego cheese is a high-fat pressed ewe's-milk cheese made in Castilla-La Mancha (Spain) and produced by enzymatic coagulation. The minimum ripening time before marketing required by the Regulatory Board of the Manchego Cheese Appellation of Origin is 60 days. This paper describes the physicochemical, proteolysis, sensory and texture characteristics of Manchego cheese, and the degree of homogeneity of cheeses made under the Manchego Appellation of Origin. The data gathered in this study indicate that sensory and instrumental analysis are useful tools for detecting changes in Manchego cheese during ripening. These changes were first detected by the instrumental analysis (2 months). The panelists detected differences after 4 months' ripening in all the factories. With physicochemical analysis, on the other hand, longer ripening times (6,8 months) are required before such changes become appreciated. [source]

MECHANICAL PROPERTIES OF UNPRESSED SEMI-HARD CHEESES BY UNIAXIAL COMPRESSION

JOURNAL OF TEXTURE STUDIES, Issue 2 2000
BRIGITTE WEINRICHTER
ABSTRACT Different lots of Tilsit cheeses, which are characterized by their open structure caused by pressing under their own weight during manufacture, were subjected to uniaxial compression, a quasi-standard for the evaluation of mechanical properties of hard and semi-hard cheeses. Additionally, video films showing the behaviour of the specimens during compression were analysed. For standard Tilsit with a fat content of 35% in dry matter, the cheese mass proved to be highly anisotropic with respect to stress response and lateral expansion expressed as apparent Poisson number. Specimens cut perpendicular to the flat side of the cheese wheels, which had lentil-shaped eyes with their major axis parallel to the compression plates, showed significantly higher stresses and lower Poisson numbers than specimens sampled parallel to the flat side of the cheese wheels. Therefore, stress values calculated on the basis of actual specimen diameter were different from those calculated by assuming constant specimen's volume. However, for samples with a fat content of approx. 60% in dry matter no differences caused by compression direction were observed. [source]

POST-PASTEURIAN CULTURES: The Microbiopolitics of Raw-Milk Cheese in the United States

CULTURAL ANTHROPOLOGY, Issue 1 2008
HEATHER PAXSON
ABSTRACT Out of concern for public health, the U.S. government bans the sale of cheese made from unpasteurized milk if it is aged fewer than 60 days. But while the FDA views raw-milk cheese as a potential biohazard, riddled with pathogenic microbes, aficionados see it as the reverse: as a traditional food processed for safety by the action of good microbes. This article offers a theoretical frame for understanding the recent rise in American artisan raw-milk cheese production, as well as wider debates over food localism, nutrition, and safety. Drawing on ethnographic interviews with cheese makers and purveyors and on participant-labor conducted on a Vermont sheep dairy farm, I develop the concept of microbiopolitics to analyze how farmer,cheese makers, industry consultants, retailers, and consumers negotiate Pasteurian (hygienic) and post-Pasteurian (probiotic) attitudes about the microbial agents at the heart of raw-milk cheese and controversies about this nature,culture hybrid. [source]

Bread, Cheese and Genocide: Imagining the Destruction of Peoples in Medieval Western Europe

HISTORY, Issue 307 2007
LEN SCALES
Western European society in the middle ages is generally perceived as lying, in its modes of thought and action, far remote from those acts of mass ethnic destruction which have been a recurrent element in world history since the early twentieth century. Yet medieval Europeans too were capable of envisaging the violent obliteration of peoples. Indeed, the view that such acts had occurred in times past and were liable to occur again was deeply embedded in medieval thought and assumption. For some commentators, the destruction of certain peoples was inseparable from the making of others, an essential motor of historical change, underpinned by biblical narratives of divine election and condemnation. Such notions constituted a matrix within which medieval writers interpreted real acts of social and political violence, the scale and the ethnic foundations of which they were thus naturally inclined to inflate. Nevertheless, their belief in the recurrent historical reality of ethnic destruction was, in their own terms, well founded , although medieval conceptions of what constituted the undoing of peoples were broader than most modern definitions of ,genocide'. By the later middle ages, moreover, government was increasingly perceived , not without justification , as a powerful agent for remaking the ethnic map. [source]

The effects of starter culture on chemical composition, microbiological and sensory characteristics of Turkish Ka,ar Cheese during ripening

INTERNATIONAL JOURNAL OF DAIRY TECHNOLOGY, Issue 4 2007
DURMU
Ka,ar cheese samples were produced from raw milk and starter culture-added pasteurized milk. Chemical, microbiological and organoleptic properties of ka,ar cheeses were analysed at certain times during the ripening periods (on the 1st, 7th, 15th, 30th, 60th, 90th days). Generally, chemical parameters were not affected by starter culture. The pH, ripening index, water-soluble nitrogen and non-protein nitrogen did not show significant differences between the cheese samples. The addition of starter affected the microbiological quality of the cheeses. Starter culture-added ka,ar cheeses contained low levels of total aerobic mesophilic bacteria, moulds and yeasts, and coliforms, and achieved higher organoleptic scores than those of cheeses made from raw milk. The starter cultures contributed to acidity and microbial quality of the cheese. [source]

Rapid Profiling of Swiss Cheese by Attenuated Total Reflectance (ATR) Infrared Spectroscopy and Descriptive Sensory Analysis

JOURNAL OF FOOD SCIENCE, Issue 6 2009
N.A. Kocaoglu-Vurma
ABSTRACT:, The acceptability of cheese depends largely on the flavor formed during ripening. The flavor profiles of cheeses are complex and region- or manufacturer-specific which have made it challenging to understand the chemistry of flavor development and its correlation with sensory properties. Infrared spectroscopy is an attractive technology for the rapid, sensitive, and high-throughput analysis of foods, providing information related to its composition and conformation of food components from the spectra. Our objectives were to establish infrared spectral profiles to discriminate Swiss cheeses produced by different manufacturers in the United States and to develop predictive models for determination of sensory attributes based on infrared spectra. Fifteen samples from 3 Swiss cheese manufacturers were received and analyzed using attenuated total reflectance infrared spectroscopy (ATR-IR). The spectra were analyzed using soft independent modeling of class analogy (SIMCA) to build a classification model. The cheeses were profiled by a trained sensory panel using descriptive sensory analysis. The relationship between the descriptive sensory scores and ATR-IR spectra was assessed using partial least square regression (PLSR) analysis. SIMCA discriminated the Swiss cheeses based on manufacturer and production region. PLSR analysis generated prediction models with correlation coefficients of validation (rVal) between 0.69 and 0.96 with standard error of cross-validation (SECV) ranging from 0.04 to 0.29. Implementation of rapid infrared analysis by the Swiss cheese industry would help to streamline quality assurance. [source]

Effect of pH on Microstructure and Characteristics of Cream Cheese

JOURNAL OF FOOD SCIENCE, Issue 2 2009
R.R. Monteiro
ABSTRACT:, This study evaluated the effect of pH on the microstructure of cream cheese and compared pH-induced changes in its microstructure with concomitant changes in cheese firmness and meltability. On 4 different days, experimental batches of cultured hot pack cream cheese were manufactured and analyzed for initial chemical composition. The cheeses were then sectioned into samples that were randomly assigned to 7 different treatment groups. Three groups were exposed to ammonia vapor for 1, 3, and 5 min to increase the pH; 3 groups were exposed to acetic acid vapor for 30, 60, and 90 min to decrease the pH; and 1 unexposed group served as the control. After equilibration at 4 °C, samples were analyzed for pH, firmness, meltability, and microstructure by scanning electron microscopy. The effects of experimental treatments on cheese pH, firmness, and meltability were analyzed by randomized complete block analysis of variance (ANOVA). Relationships between cheese pH and firmness and meltability were evaluated by regression. Experimental treatments significantly affected cheese pH, firmness, and meltability. Cheese firmness decreased and meltability increased with increasing pH from about pH 4.2 to 6.8. Cheese microstructure also changed dramatically over the same approximate pH range. Specifically, the volume of the protein network surrounding the fat droplets increased markedly with increasing pH, presumably due to casein swelling. These data support the hypothesis that protein-to-water interactions increased as the cheese pH increased, which gave rise to progressive swelling of the casein network, softer texture, and increased meltability. [source]

Electronic Nose Technology in Quality Assessment: Predicting Volatile Composition of Danish Blue Cheese During Ripening

JOURNAL OF FOOD SCIENCE, Issue 6 2005
Jeorgos Trihaas
ABSTRACT This work describes for the 1st time the use of an electronic nose (e-nose) for the determination of changes of blue cheeses flavor during maturation. Headspace analysis of Danish blue cheeses was made for 2 dairy units of the same producer. An e-nose registered changes in cheeses flavor 5, 8, 12, and 20 wk after brining. Volatiles were collected from the headspace and analyzed by gas chromatography-mass spectrometry (GC-MS). Features from the chemical sensors of the e-nose were used to model the volatile changes by multivariate methods. Differences registered during ripening of the cheeses as well as between producing units are described and discussed for both methods. Cheeses from different units showed significant differences in their e-nose flavor profiles at early ripening stages but with ripening became more and more alike. Prediction of the concentration of 25 identified aroma compounds by e-nose features was possible by partial least square regression (PLS-R). It was not possible to create a reliable predictive model for both units because cheeses from 1 unit were contaminated by Geotrichum candidum, leading to unstable ripening patterns. Correction of the e-nose features by multiple scatter correction (MSC) and mean normalization (MN) of the integrated GC areas made correlation of the volatile concentration to the e-nose signal features possible. Prediction models were created, evaluated, and used to reconstruct the headspace of unknown cheese samples by e-nose measurements. Classification of predicted volatile compositions of unknown samples by their ripening stage was successful at a 78% and 54% overall correct classification for dairy units 1 and 2, respectively. Compared with GC-MS, the application of the rapid and less demanding e-nose seems an attractive alternative for this type of investigation. [source]

Method Development for Assessing the Complete Process of Crumbling Cheese Using Hand Evaluation

JOURNAL OF FOOD SCIENCE, Issue 4 2004
S. Sandra
ABSTRACT: Cheese sensory evaluation was conducted by trained panelists (n= 8) on 4 commercial cheese samples (feta, Monterey Jack, 2 brands of Queso Fresco) in duplicate. Fifteen descriptors, capturing the entire process of crumbling cheese, were tested. Degree of crumbliness was defined as the ease by which the sample breaks apart during manipulation by rolling the sample using replicated circular movements, with the thumb, forefinger, and middle finger, 5 times. Using principal component analysis, 4 components were extracted and moistness, crumbliness, color, cohesiveness, irregularity, and oiliness were the main descriptors differentiating the samples. Panelists' performances were not significantly different (P, 0.05), and each subject used the method consistently for crumbliness. [source]

Profile of Biogenic Amines in Goat Cheese Made from Pasteurized and Pressurized Milks

JOURNAL OF FOOD SCIENCE, Issue 8 2002
S. Novella-Rodríguez
ABSTRACT: The formation of biogenic amines in goat cheese can be prevented through ensuring hygiene in raw materials and during manufacture, thereby avoiding potential decarboxylating microorganisms. High-pressure treatment may be used to inactivate microorganisms and is a potential alternative to pasteurization. This treatment could provoke higher proteolysis than pasteurization, leading to a higher availability of biogenic amine precursors. We compared the biogenic amine profile throughout the ripening of goat cheese made from pressurized milk with that obtained from pasteurized milk. Results indicate that the profile of biogenic amines is very similar for both cheeses. Tyramine was the prevailing amine in both cheeses, followed by cadaverine, putrescine, and histamine. [source]

Texture Changes During the Ripening of Port Salut Argentino Cheese in 2 Sampling Zones

JOURNAL OF FOOD SCIENCE, Issue 5 2002
R.A. Verdini
ABSTRACT: Texture changes during ripening of Port Salut Argentino cheese for different sampling zones were studied. Compression relaxation tests were performed and results were analyzed using both Maxwellian and Peleg's models. Elastic equilibrium modulus obtained from the Maxwellian model decreased from 1.22 to 0.11 104Pa during ripening. The constants derived from Peleg's model, k1 and k2, diminished with ripening time from 1.18 to 0.71 min and from 1.27 to 1.12, respectively. Asymptotic equilibrium modulus from Peleg's model decreased from 0.95 to 0.07 104Pa during ripening. Rate parameters derived from a 1st order kinetics applied to both equilibrium moduli showed that the decrease was faster in the external zone (0.0846 d,1) than in the central zone (0.0368 d,1). The correlation between equilibrium moduli, salt concentration, moisture content, and maturation indexes was obtained with a determination coefficient of 0.76. [source]

Isolation and Identification of Low-Molecular-Weight Peptides from Emmentaler Cheese

JOURNAL OF FOOD SCIENCE, Issue 2 2002
C. Combes
ABSTRACT: Four peptides, derived from the N-terminal fragment of ,sl -casein [CN (1,9), CN (1,12), CN (1,13) and CN (1,14)] were isolated from a low-molecular-weight extract of a commercial Emmentaler cheese (age: approx. 5.5 mo) by gel filtration and RP-FPLC. Capillary zone electrophoresis was used to check the purity of the peptides. Using automatic Edman degradation and MALDI-TOF mass spectrometry, amino acid sequence and molecular mass of the peptides were determined to identify them. The peptide ,sl -CN (1,13) was identified for the first time in Emmentaler cheese. The peptide fraction was shown not to contribute to the characteristic flavor of Emmentaler cheese. [source]

Casein Hydrolysate Fractions Act as Emulsifiers in Process Cheese

JOURNAL OF FOOD SCIENCE, Issue 2 2002
H.S. Kwak
ABSTRACT: Degrees of hydrolysis and emulsifying activity of casein hydrolysates were the highest at 4 h hydrolysis. The oil-off values of the mixture of hydrolysate (H) or supernatant (S) and traditional emulsifier (T) were not significantly different from the control made with traditional emulsifier, except for S + T = 3:1. Two other samples made with hydrolysate or supernatant only (H or S) showed higher oil-off value than the others (p < 0.05). In flavor property, no difference was found between samples made with traditional emulsifier and those made with the mixture of hydrolysate or supernatant at the ratio of 3 to 1. Therefore, these results indicated that a mixture of the hydrolysate or supernatant and traditional emulsifier might replace a traditional emulsifier in process cheese manufacturing. [source]