Appearance Of Cheeses Research Articles

Widespread Enlarged Perivascular Spaces in a Patient with Delirium: Swiss Cheese Appearance

Widespread Enlarged Perivascular Spaces in a Patient with Delirium: Swiss Cheese Appearance

Микробиологические риски как причина пороков внешнего вида сыра

Aerobic Bacillus bacteria, yeasts, and micrococci are pigment-forming microorganisms responsible for color defects in cheese production. The article describes their environment, industry-related characteristics, types of defects they cause, and various color violations in commercial cheeses. The research featured domestic cheeses with yellow and red surface spots that appeared during industrial ripening and storage. Pigment-forming microorganisms developed on cheese surface at a low ripening temperature, high concentration of table salt, and critically low oxygen. Pigment-forming microflora proved to enter cheese from milk, brine, or production environment, e.g., water, air, and processing equipment, dry and succulent feeds being the main source of milk contamination with spore-forming aerobic bacteria, yeast, mold fungi, etc. Contamination of raw milk, milking equipment, and air environment with micrococci was primarily associated with cows’ udder and skin. Cheese production presupposes low-temperature heat treatment of raw milk, which means possible residual microflora in pasteurized milk. As a result, the total count of mesophilic aerobic and optionally anaerobic microorganisms, i.e., the potential pigment formers, was to stay below 104 CFU/cm3. Yeast and spore-forming Bacillus microorganisms demonstrated the acceptable level of ≤102 CFU/cm3 in milk intended for cheesemaking. If their total count exceeded 103 CFU/cm3, it indicated high microbiological risks of cheese appearance defects. The microflora responsible for discoloration of cheese surface was represented by yeast, micrococci, aerobic spores, or their combinations.

Epicoccum sp. as the causative agent of a reddish-brown spot defect on the surface of a hard cheese made of raw ewe milk

Colour defects can affect the appearance of cheese, its flavour, the safety of its consumption, and the price it can demand. This work reports the identification of five fungal isolates from a dairy plant where the surface of most cheeses was affected by patent, reddish-to-brown stains. One of these isolates was obtained from cheese, two from brine, and two from a bulk tank containing ewe milk. Molecular identification by partial amplification, sequencing, and database comparison of the concatenated sequence of the genes coding for the largest subunit of RNA polymerase II (RPB2), β-tubulin (β-TUB), and the large subunit of the rRNA molecule (LSU), plus the internal transcribed sequence (ITS) regions, assigned the isolates to Epicoccum layuense, Epicoccum italicum, and Epicoccum mezzettii. Features of the growth of these different species on different agar-based media, and of the morphology of their conidia following sporulation, are also reported. The strain isolated from cheese, E. layuense IPLA 35011, was able to recreate the reddish-brown stains on slices of Gouda-like cheese, which linked the fungus with the colour defect. In addition, two other strains, E. italicum IPLA 35013 from brine and E. italicum IPLA 35014 from milk, also produced stains on cheese slices. Epicoccum species are widely recognized as plant pathogens but have seldom been reported in the dairy setting, and never as human or animal pathogens.

Stuffed cheese with superficial Penicillium nalgiovense development: Role of microperforated film packaging in the ripening process

The impact of microperforated polyethylene film packaging on the ripening process of a stuffed cheese with superficial fungal growth was evaluated. Cheeses were manufactured in a pilot plant using synthetic casings. Penicillium nalgiovense was superficially inoculated and the cheeses were ripened at 12 °C and 90% relative humidity until packaged using a microperforated polyethylene film on day 14. The ripening process continued at either 5 °C or 12 °C for 29 days. Results showed that the packaging used was useful in decreasing dehydration while maintaining fungal viability. After packing, the external appearance of cheeses was not modified. SEM micrographs did not show high disintegration of the fungal hyphae throughout the ripening time. Fungal peptidases passed through the casing contributing to proteolysis.

Camembert-type cheese quality and safety implications in relation to the timing of high-pressure processing during aging

Bloomy rind cheeses, including Brie, Camembert, and related varieties, are at high risk of contamination by environmental pathogens during manufacture and ripening. This risk is particularly high during ripening due to open-air exposure of the product. Currently, no kill step is applied after manufacture or post ripening to control food safety risks associated with Listeria monocytogenes contamination. Instead, cheesemakers must rely on sanitation and environmental monitoring to reduce this risk. High-pressure processing (HPP) is a nonthermal food-processing technology that can effectively reduce bacterial contaminants with minimal impact on the organoleptic properties of various foods. The objective of this study was to evaluate HPP as a potential intervention to maintain Camembert cheese quality and reduce risk associated with L. monocytogenes. Timing of HPP treatments (3, 11, and 45 d after manufacture) was based on the growth of L. monocytogenes during Camembert cheese ripening. High-pressure processing treatment of fully ripened cheeses (45 d) resulted in destruction of the surface mold, which caused browning and yellowing of the cheese rind. Applying HPP treatment earlier in the ripening process (11 d) resulted in a similar degradation of cheese appearance, which did not improve with continued ripening. Applying HPP treatment shortly after production (3 d; before the surface flora developed) delayed the development of the cheese rind and the textural ripening of the cheese. This early treatment time also resulted in free whey being expelled from the cheese, creating a firmer body. Applying HPP 11 d after manufacture resulted in >5 log reduction of L. monocytogenes at 450 and 550 MPa with holding times of 10 min. Although HPP was effective at reducing L. monocytogenes associated with bloomy rind cheeses, the quality deterioration would be unacceptable to consumers. Cheesemakers must continue to emphasize sanitation and environmental monitoring to reduce the risk of L. monocytogenes in bloomy rind cheeses.

Milk fat composition modifies the texture and appearance of Cantal-type cheeses but not their flavor

Although the effects of cow diet on cheese sensory properties have been well documented, the putative interactions between the biochemical and microbial milk components and their respective roles in the development of the sensory properties of cheeses have yet to be explored in depth. The aim of this study was to evaluate the specific contribution of milk fat composition to the formation of cheese sensory properties. Two creams with different fat compositions were obtained from cows fed either pasture or maize silage. Cheeses were manufactured from the same skim milk (identical chemical and microbial composition) with either the pasture- or maize silage-origin pasteurized cream added. The gross composition and microbial composition of milks did not vary with cream origin. In milks and cheeses, the fatty acid (FA) profiles were modified by the origin of the cream. The concentrations of C18:0 and unsaturated FA such as cis-9 C18:1, trans-11 C18:1, C18:3n-3, total conjugated linoleic acids, and mono- and polyunsaturated FA were higher in milks and cheeses with the pasture-origin cream than in those with the maize-origin cream. In contrast, the maize milks and cheeses had higher concentrations of short- and medium-chain saturated FA, C16:0, and C18:2n-6. The level of lipolysis was 11% in the cheese rind and only 0.30% in the cheese core. The rind of pasture cheeses had a higher concentration of free C18:0 and C18:3n-3 and a lower concentration of free C14:0 and free C16:0 than the rind of maize cheeses. The levels of major microbial groups were similar in pasture and maize cheeses at different stages of ripening. The pasture cheeses had a more elastic and creamier texture, a yellower color, and a thinner rind than the maize cheeses, but the odor and aroma of cheeses were not affected by the origin of the cream, despite a few modifications in the balance of volatile compounds from FA catabolism. Based on these results, we conclude that milk fat composition modulated by cow diet had a direct role in the texture of the cheese but no effect on flavor. The high degree of lipolysis in cheese rind, along with the higher concentration of long-chain unsaturated free FA in pasture cheeses may be responsible for antimicrobial activity, which could explain differences in the appearance of cheese rind.

Feeding reduced-fat dried distillers grains with solubles to lactating Holstein dairy cows does not alter milk composition or cause late blowing in cheese

Feeding dried distillers grains with solubles (DDGS) to lactating dairy cows has been implicated as a cause of late blowing defects in the production of Swiss-style cheeses. Our objectives were (1) to test the effect of feeding reduced-fat DDGS (RF-DDGS; ∼6% fat) to lactating dairy cows on the composition of milk and on the suitability of the milk for production of baby Swiss cheese and (2) to evaluate the effect of diet on cow lactation performance. Lactating Holstein dairy cows were fed both dietary treatments in a 2 × 2 crossover design. Cows were housed in a 48-cow freestall pen equipped with individual feeding gates to record feed intake. The control diet was a corn, corn silage, and alfalfa hay diet supplemented with mechanically expelled soybean meal. The experimental diet was the same base ration, but 20% (dry matter basis) RF-DDGS were included in place of the expelled soybean meal. The RF-DDGS diet was additionally supplemented with rumen-protected lysine; diets were formulated to be isoenergetic and isonitrogenous. Cows were allowed ad libitum access to feed and water, fed twice daily, and milked 3 times daily. For cheese production, milk was collected and pooled 6 times for each dietary treatment. There was no treatment effect on milk yield (35.66 and 35.39 kg/d), milk fat production (1.27 and 1.25 kg/d), milk fat percentage (3.65 and 3.61%), milk protein production (1.05 and 1.08 kg/d), lactose percentage (4.62 and 4.64%), milk total solids (12.19 and 12.28%), and somatic cell count (232.57 and 287.22 × 103 cells/mL) for control and RF-DDGS, respectively. However, dry matter intake was increased by treatment, which implied a reduction in feed efficiency. Milk protein percentage also increased (3.01 and 3.11%), whereas milk urea nitrogen decreased (14.18 and 12.99 mg/dL), indicating that protein utilization may be more efficient when cows are fed RF-DDGS. No differences in cheese were observed by a trained panel except cheese appearance; control cheese eyes were significantly, but not practically, larger than the RF-DDGS cheese. These results indicate that RF-DDGS can be effectively used in the rations of lactating Holstein cows with no deleterious effects on milk production and composition and metrics of the physiology of the cow (i.e., blood glucose and nonesterified fatty acids); however, feeding RF-DDGS increased dry matter intake, which decreased feed efficiency. Finally, feeding RF-DDGS did not negatively influence quality and suitability of milk for production of baby Swiss cheese.

Effect of high-pressure-processing on lipolysis and volatile compounds of Brie cheese during ripening and refrigerated storage

Brie cheeses were high pressure (HP)-treated at 400 or 600 MPa, on days 14 or 21 after manufacture, to prevent over-ripening. HP-treatment reduced total free fatty acid content of 120-day-old cheese by up to 88.5%. On day 120, HP-treated cheeses had levels of alcohols, aldehydes, acids, esters and ethers up to 3.4, 1.9, 43.8, 18.7 and 5.6 times higher, respectively, than control cheese, while ketones and hydrocarbons levels were up to 88.6% and 48.9% lower, respectively. Levels of sulphur compounds, pyrazines and amines increased drastically in control cheese from day 60 onwards, resulting in lower odour quality scores. On day 120, HP-treated cheeses had levels of sulphur compounds, pyrazines and amines up to 96.9%, 99.3% and 99.4% lower, respectively, than control cheese. Cheese appearance was impaired by HP-treatment, resulting in lower lightness and slightly more reddish and yellowish colour. These changes might diminish consumer acceptance of HP-treated Brie cheese.

Quantification of pizza baking properties of different cheeses, and their correlation with cheese functionality.

The aim of this study is to quantify the pizza baking properties and performance of different cheeses, including the browning and blistering, and to investigate the correlation to cheese properties (rheology, free oil, transition temperature, and water activity). The color, and color uniformity, of different cheeses (Mozzarella, Cheddar, Colby, Edam, Emmental, Gruyere, and Provolone) were quantified, using a machine vision system and image analysis techniques. The correlations between cheese appearance and attributes were also evaluated, to find that cheese properties including elasticity, free oil, and transition temperature influence the color uniformity of cheeses.

Echocardiography in the diagnosis of apical non-compaction associated with congenital heart diseases.

Isolated left ventricular non-compaction has been reported extensively. However, apical non-compaction of both ventricles and the interventricular septum (IVS) is not often reported in the literature. The objective of our study is to evolve the echocardiographic diagnostic criteria and to assess the types and impact of the associated lesions in "apical non-compaction". Seventy consecutive cases that fulfilled standard echocardiographic criteria for non-compaction of the left ventricle and, in addition, N/C ratio of >3 for the right ventricle and apical IVS formed the material. The age of patients ranged from 3days to 35years, with 37 males and 33 females. The associated lesions were present in all 70 cases: 62 had acyanotic (88.6%) and 8 had cyanotic congenital heart diseases (11.4%). Of the 70 cases, 18 had pump failure (25.7%): 8 cases had left ventricular dysfunction, 7 had right ventricular dysfunction, and 3 had biventricular dysfunction; 33 (47.1%) had pulmonary hypertension, 2 (2.9%) had thrombus, and 1 (1.4%) had tachyarrhythmia. Pump failure was worsened by volume overload in 33.9% and by pressure overload in 8.1% of cases. Some very rare lesions were detected. All 70 cases had Swiss cheese appearance of the apical half of the IVS, looking like the delta of a river. All of the apical non-compaction syndrome cases had associated lesions, mostly acyanotic congenital heart disease with volume overload, rather than obstructive lesions. Transthoracic echocardiography plays an important role in the diagnosis of apical non-compaction syndrome and associated lesions that worsen the pump failure.

Consumer acceptance and sensory evaluation of Monti Dauni Meridionali Caciocavallo cheese

Twelve Caciocavallo cheeses were collected from 6 factories (A, B, C, D, E, F) located in the Monti Dauni Meridionali area (Southern Italy) that adopted different protocols for cheese production. A total of 160 consumers were involved in the sensory evaluation of Caciocavallo cheese after 180d of ripening. Cheese attributes were used to describe the flavor, texture, and appearance of cheeses. The highest scores for the shiny attribute were assigned to cheeses B, C, and E, whereas color intensity was the highest in cheeses B, D, and F. Strength, salty, and piquant attributes were higher in cheeses F and A because of the use of raw milk (F), rennet paste (A), and percentage of salt in the brine (A, F). Consumers perceived a more granular structure during the second half of chewing of Caciocavallo cheese F, as evidenced by the highest value for the grainy attribute. A positive correlation was found between overall flavor and odor intensity and water-soluble nitrogen, low molecular weight peptides, and free fatty acids and between piquant and butyric and caproic acids. A principal components analysis applied to the sensory attributes accounted for 65% of the total variance. The score plot showed that cheeses F and A were located in a well-defined zone of the plot, with cheeses in this zone displaying higher levels of strength, piquant, and salty attributes. The preference test assigned 40% of the preference to Caciocavallo cheese A, 38% to cheese F, 9% to cheese E, 8% to cheese D, and 7% to cheeses B and C. Sensory evaluation of Monti Dauni Meridionali Caciocavallo cheeses is a useful analysis to highlight the principal attributes able to influence consumers’ liking that are related to biochemical features of the cheese.

Color of low-fat cheese influences flavor perception and consumer liking

The present study examines the effect of color on low-fat cheese flavor perception and consumer acceptability. To understand the flavor preferences of the consumer population participating in the sensory testing, 4 brands of retail full-fat Cheddar cheeses labeled as mild, medium, or sharp were obtained. These cheeses were evaluated by a trained descriptive panel to generate a flavor profile for each cheese and then by consumer sensory panels. Overall and color liking were measured using a 9-point hedonic scale, and flavor, chewiness, level of sharpness measured using a 5-point just-about-right (JAR) scale (with 1 being not enough, 3 being just about right, and 5 being too much of the attribute). Subsequently, 9 low-fat Cheddar cheeses were manufactured using 3 levels of annatto (0, 7.34, and 22g/100kg) and 3 levels of titanium dioxide (0, 7.67, and 40g/100kg) using a randomized block design in duplicate. Cheeses were then evaluated by descriptive and consumer sensory panels. Each consumer testing consisted of 120 panelists who were mainly 18 to 35 yr of age (>90% of total populace) with >60% being frequent cheese consumers. Overall liking preference of the consumer group was for mild to medium cheese. Using the JAR scale, the medium cheeses were considered closest to JAR with a mean score of 3.0, compared with 2.4 for mild cheese and 3.6 for sharp cheese. Among low-fat cheeses, color was shown to be important with consumer liking being negatively influenced when the cheese appearance was too translucent (especially when normal levels of annatto were used) or too white. Matching the level of titanium dioxide with the annatto level gave the highest liking scores and flavor perception closest to JAR. This study established a significant effect of color on overall liking of low-fat versions of Cheddar cheese.

The effect of pectin concentration on viscoelastic and sensory properties of processed cheese

SummaryThe effect of pectin addition on viscoelastic properties of model processed cheeses with 40% w/w dry matter and 50% w/w fat in dry matter after 42 days of storage at temperature 6 ± 2 °C has been investigated using dynamic oscillation rheometry (plate–plate geometry; frequency range 0.1–50.0 Hz; temperature 20 °C). The role of pectin concentration (0.2%, 0.4%, 0.6% and 0.8% w/w) has been studied. Also, the sensory evaluation of samples has been made to assess cheese appearance, rigidity, spreadability and flavour. All samples with the pectin addition were more rigid and less spreadable compared with processed cheeses without pectin. With the increasing concentration of pectin the storage (G′) and loss (G″) moduli rose at the whole tested frequency range (0.1–50.0 Hz). Growing pectin content resulted in the decrease in loss tangent (the nature of gel was changed to more elastic material). The dependence of processed cheese rigidity on pectin concentration (in range 0–0.8% w/w) was not linear. The appearance and flavour were not worse by pectin addition.

Effects of Atmospheric Composition on Respiratory Behavior, Weight Loss, and Appearance of Camembert-Type Cheeses During Chamber Ripening

Respiratory activity, weight loss, and appearance of Camembert-type cheeses were studied during chamber ripening in relation to atmospheric composition. Cheese ripening was carried out in chambers under continuously renewed, periodically renewed, or nonrenewed gaseous atmospheres or under a CO2 concentration kept constant at either 2 or 6% throughout the chamber-ripening process. It was found that overall atmospheric composition, and especially CO2 concentration, of the ripening chamber affected respiratory activity. When CO2 was maintained at either 2 or 6%, O2 consumption and CO2 production (and their kinetics) were higher compared with ripening trials carried out without regulating CO2 concentration over time. Global weight loss was maximal under continuously renewed atmospheric conditions. In this case, the airflow increased exchanges between cheeses and the atmosphere. The ratio between water evaporation and CO2 release also depended on atmospheric composition, especially CO2 concentration. The thickening of the creamy underrind increased more quickly when CO2 was present in the chamber from the beginning of the ripening process. However, CO2 concentrations higher than 2% negatively influenced the appearance of the cheeses.

Microbiological and Biochemical Aspects of Camembert-Type Cheeses Depend on Atmospheric Composition in the Ripening Chamber

Camembert-type cheeses were prepared from pasteurized milk seeded with Kluyveromyces lactis, Geotrichum candidum, Penicillium camemberti, and Brevibacterium aurantiacum. Microorganism growth and biochemical dynamics were studied in relation to ripening chamber CO2 atmospheric composition using 31 descriptors based on kinetic data. The chamber ripening was carried out under 5 different controlled atmospheres: continuously renewed atmosphere, periodically renewed atmosphere, no renewed atmosphere, and 2 for which CO2 was either 2% or 6%. All microorganism dynamics depended on CO2 level. Kluyveromyces lactis was not sensitive to CO2 during its growth phases, but its death did depend on it. An increase of CO2 led to a significant improvement in G. candidum. Penicillium camemberti mycelium development was enhanced by 2% CO2. The equilibrium between P. camemberti and G. candidum populations was disrupted in favor of the yeast when CO2 was higher than 4%. Growth of B. aurantiacum depended more on O2 than on CO2. Two ripening progressions were observed in relation to the presence of CO2 at the beginning of ripening: in the presence of CO2, the ripening was fast-slow, and in the absence of CO2, it was slow-fast. The underrind was too runny if CO2 was equal to or higher than 6%. The nitrogen substrate progressions were slightly related to ripening chamber CO2 and O2 levels. During chamber ripening, the best atmospheric condition to produce an optimum between microorganism growth, biochemical dynamics, and cheese appearance was a constant CO2 level close to 2%.

Deacidification by Debaryomyces hansenii of Smear Soft Cheeses Ripened Under Controlled Conditions: Relative Humidity and Temperature Influences

Model smear soft cheeses were prepared from pasteurized milk inoculated with Debaryomyces hansenii (304, GMPA) and Brevibacterium aurantiacum (ATCC 9175) under aseptic conditions. Debaryomyces hansenii growth and curd deacidification were studied in relation to ripening chamber temperature and relative humidity (RH). A total of 9 descriptors, mainly based on kinetic data, were defined to represent D. hansenii growth (2 descriptors), cheese deacidification (5 descriptors), and cheese ripening (2 descriptors). Regardless of the temperature, when the RH was 85%, D. hansenii growth was inhibited due to limitation of carbon substrate diffusions; consequently, cheese deacidification did not take place. Debaryomyces hansenii growth was most prolific when the temperature was 16°C, and the RH was 95%. Kinetic descriptors of lactate consumption and pH increase were maximal at 16°C and 100% RH. Under these 2 ripening conditions, on d 14 (packaging) the creamy underrind represented a third of the cheese; however, at the end of ripening (d 42), cheese was too liquid to be sold. Statistical analysis showed that the best ripening conditions to achieve an optimum between deacidification and appearance of cheeses (thickness of the creamy un-derrind) were 12°C and 95±1% RH.

Effects of a commercial oat-β-glucan concentrate on the chemical, physico-chemical and sensory attributes of a low-fat white-brined cheese product

Low-fat white-brined cheese was manufactured by a traditional procedure from bovine milk (70% fat reduction) containing two levels of an oat β-glucan concentrate (CEBA Foods AB) at 0.7% and 1.4% (w/w). For comparison two controls – a full-fat and a low-fat product without addition of the β-glucan concentrate – were also examined. The results indicated that as the fat content of cheese milk decreased, the fat, moisture in non-fat solids (MNFS) and yield values significantly decreased, and the moisture and total nitrogen values increased. The products fortified with the β-glucan concentrate exhibited higher yield values and significantly lower pH (at 60 and 90 days of storage) than the control samples. In accordance with the latter values, the HPLC analysis showed that incorporation of the β-glucan concentrate into the low-fat cheese milk led to a significant increase in the production of lactic, acetic and butyric acid throughout cheese ripening. Also, the extent of proteolysis in the treatments supplemented with the hydrocolloid significantly increased, especially at 60 and 90 days and was higher than the respective values of the control products. With regard to the rheological properties of the cheeses, incorporation of the β-glucan concentrate brought about amelioration in all the textural parameters of the low-fat product, as determined by large deformation mechanical testing and sensorial analysis; significant correlations ( p<0.01) between instrumental and sensory data for hardness were identified. However, the addition of the β-glucan preparation adversely affected cheese appearance and flavour in comparison with the control samples.

Low-fat white-brined cheese made from bovine milk and two commercial fat mimetics: chemical, physical and sensory attributes

The composition, proteolysis, sensory and texture characteristics of low-fat white-brined cheeses (∼60% fat reduction) made from bovine milk and containing two commercial hydrocolloid-fat replacers (1% w/w Simplesse® D-100 and 0.125% w/w Novagel™ NC-200) were examined throughout aging for 90 d. For comparison, the low-fat variant without fat replacers (L) and the full-fat cheese (F) were also studied. All the low-fat products showed reduced values for MNFS and yield, whereas the moisture and protein content significantly increased; however, the cheeses containing fat replacers had higher moisture and yield values than the L product. The extent of proteolysis and lipolysis in the low-fat white-brined cheeses made with the fat replacers significantly increased compared to the F cheese. The kinetics of αs1-and β-casein degradation as well as the evolution of the peptide profile (reversed phase HPLC) were not largely affected by the hydrocolloids. For the cheeses containing fat replacers, the mean values of TPA (texture profile analysis) parameters and the maximum stress (σmax at 80% deformation on uniaxial compression) were significantly less than those of the L cheese, showing a great improvement in cheese texture when the fat replacers were included. The textural attributes of the product made with Novagel™ resembled more closely those of the F cheese. Significant correlations (p<0.05) with negative slopes were obtained between the variables reflecting the degree of proteolysis and instrumental (TPA) texture parameters; such relationships were even stronger when the data were analyzed for each type of cheese separately. The rheological measurements showed an improvement in the low-fat cheeses containing fat replacers, but this was not clearly evident by sensory testing. Overall, the full-fat white-brined cheese was perceived as more elastic, less salty and had higher flavor and odor intensity scores than all low-fat variants. Although Simplesse® (S) had a marked improving effect on cheese appearance, the product was rated as a harder cheese than its full-fat counterpart.

The sensory profile and consumer preference for ten speciality cheeses

The sensory characteristics that determined consumer preference for 10 speciality cheeses were investigated. These cheeses were chosen to reflect a wide range of speciality cheeses now available on the Irish market offering a diverse range of sensory characteristics. Descriptive analysis was carried out by 15 trained assessors who used a vocabulary of 47 terms to quantitatively describe cheese appearance, odour, flavour and texture. Analysis of variance found significant differences between cheeses (p &lt;.05) on the first seven principle components (which accounted for 85% of the explained variation) obtained from Principal Components Analysis of the sensory data. A total of 198 consumers related their preferences for the cheeses on a nine point hedonie scale. Internal preference mapping illustrated individual consumers' preferences for the cheeses. Hierarchical cluster analysis showed that the sampled consumer population was heterogeneous by identifying seven clusters of consumers with different preferences and demonstrated that there exists cr market for the sensory characteristics of each of the cheeses. Partial Least Squares regression was carried out to relate the sensory character of the cheeses with consumer preference scores. Gruyère, the preferred cheese of three clusters of consumers (and the most preferred cheese overall), was distinguished by a ‘fruity’ odour, a ‘balanced’ and ‘sweet’ flavour and a ‘firmness’ texture. Blue Shropshire, the preferred cheese of two clusters of consumers (hut the least liked cheese overall) was characterized by a ‘mouldy’ odour, an ’acidic’, ‘astringent’ and ‘mouldy’ flavour and cr ‘crumbly’ texture. Finally, socioeconomic data were obtained from a consumer questionnaire. These data pointed to some interesting relationships between socioeconomic variables and consumer preferences.

Effects of salting method and storage time on composition and quality of feta cheese

Feta cheese was manufactured by using five different salting methods (dry salting for one day followed by addition of 6% NaCl brine, dry salting for 1,2 or 3 days followed by addition of 7% NaCl brine and dry salting for 3 days followed by addition of 8% NaCl brine). The effects of salting method and storage time on the composition, physicochemical, organoleptic and rheological properties of feta cheese were studied. It was found that moisture was not affected by salting method or storage time. The salting method but not the storage time had a significant effect on salt content. As the salt content of cheeses increased or the storage time was prolonged the moisture decreased. pH and cheese yield were not influenced by salting method but did decrease with storage time. Protein content was not affected by salting method or storage time, whereas fat content was affected by both factors. Proteolysis, lipolysis, organoleptic and rheological properties of cheeses were not influenced by the salting methods applied. On the other hand, storage time had a significant effect on proteolysis, lipolysis, cheese appearance, fracturability and percentage compression at the yield point. Dry salting of cheese for one day and preservation in 7% NaCl brine was considered as the most appropriate salting method for practical application.