Control Cheese Research Articles

Selection, application and monitoring of Lactobacillus paracasei strains as adjunct cultures in the production of Gouda-type cheeses

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

Chemical and biochemical study of industrially produced San Simón da Costa smoked semi-hard cow's milk cheeses: Effects of storage under vacuum and different modified atmospheres

Two batches of smoked, semi-hard (ripened for 45 d) San Simón da Costa cow's milk cheeses with Protected Designation of Origin were used to investigate the chemical, biochemical, and sensorial parameters that may be affected by modified-atmosphere packaging. Cheeses were packaged for 45 d as follows: vacuum packaging, packaging in 100% N2, packaging in a gas mixture of 20% CO2/80% N2, and packaging in a gas mixture of 50% CO2/50% N2. The San Simón da Costa cheeses were characterized by high contents of lactic, oxalic, and citric organic acids. The main free amino acids found were isoleucine, phenylalanine, serine, valine, lysine, and glutamic acid, and the most abundant volatile compounds included ethanol, diacetyl, 2-butanol, isopropyl alcohol, furfural, acetaldehyde, 2-butanone, acetone, and 2-methylfuran. Modified atmospheres appeared to alter the ripening processes by affecting lipolysis, as indicated by the lower concentrations of butyric and propionic acids compared with control cheeses. In addition, modified-atmosphere packaging altered the proteolysis processes, yielding higher amounts of branched-chain alcohols. The results revealed that storage under modified atmosphere contributes to the accumulation of several compounds probably derived from smoke, including aldehydes such as 2-furancarboxaldehyde (furfural), alcohols such as 2-methoxyphenol (guaiacol), ketones such as 2-cyclopenten-1-one, and esters such as methyl furancarboxylate, which were negatively correlated with flavor. Vacuum packaging was the most useful technique in terms of preserving the sensory quality of San Simón da Costa Protected Designation of Origin cheeses. Considering the current demands for packaged portions of food at the distribution and retail levels and the potential health risks associated with some smoke-derived compounds usually present in some smoked foods, the results obtained in this study may be of special interest to the cheese industry.

Monitoring the Chemical and Microbiological Changes During Ripening of Iranian Probiotic Low-Fat White Cheese

Problem statement: The objective of this experiment was to manufacture an Iranianlow fat probiotic cheese. Approach: Iranian white brine cheeses (4 trials) were made by varyingprocesses, i.e., lowering the fat content and use of probiotic adjunct culture on separate days. All types of cheeses were ripened at 13°C for 2 weeks and at 6°C to the end of ripering period. Cheeses were analyzed for the compositional, microbiological, color and sensory characteristics and also lipolysis and organic acid profile. The Cheese of each trial was sampled at 1, 15, 30, 45 and 60 days during ripening. Results: Decreasing the fat level resulted in significant increases (p<0.05) in the level of moisture, protein and pH of whey. The results show that probiotic cheeses had higher moisture and pH than cheeses with bacteria (p<0.05). There were no significant differences (p>0.05) between the concentration of L. acidophilus of cheese groups when the fat content of samples was reduced. The rate and extent of lipolysis in the full-fat cheese was higher than in the low-fat control cheese (p<0.05). Results also showed decreasing fat content and addition of adjunct culture to the cheese treatments decreased the acetic and lactic acid contents (p<0.05). Decreasing the fat content of cheese samples and use of both factor in the treatments increased the a* value in the samples. Low fat cheeses received higher flavor and odor scores than full fat cheeses. Also addition of adjunct culture significantly (p<0.05) decrease the texture score of manufactured cheeses. Conclusion: Therefore the results of this study showed that the Iranian probotic low fat cheese is a functional food. It has better flavor and odor than normal cheese and can be used in many cases like as heart disease and obesity.

Effect of the inclusion of artichoke silage in the ration of lactating ewes on the properties of milk and cheese characteristics during ripening

The effect of including artichoke silage in the rations of dairy ewes on milk characteristics and biochemical changes of ripened cheeses was evaluated. Four groups of lactating ewes were fed rations containing 0, 10, 20, or 30% artichoke silage on a dry matter basis. Bulk milk samples were collected 3 times during the feeding period, and semi-hard cheeses were manufactured and sampled during ripening. Milk composition and cheese yield were not affected by diet. Inclusion of 20 and 30% artichoke silage reduced the firmness of the curds at a level only detected by the Gelograph (Gelograph-NT, Gel-Instrumente, Thalwil, Switzerland) probe. Inclusion of artichoke silage in ewes’ diet decreased fat and total free fatty acids content of these cheeses and increased total free amino acids content. Despite the effect of diet on cheese ripening characteristics, the overall sensory scores for cheeses corresponding to artichoke silage diets were statistically higher than those for the control cheeses.

PRODUCTION UNDER CONTROLLED CONDITIONS OF “CASU MARZU” CHEESE: EFFECT OF THE Piophila Casei COLONIZATION ON MICROBIAL AND CHEMICAL COMPOSITION OF THE CHEESES

The aim of the present study was to evaluate the effect of the Piophila casei colonization under controlled conditions on &ldquo;casu marzu&rdquo;, a typical Sardinian sheep milk cheese. Three batches of two different kind of cheese (PO, holed paste and PC, firm paste) were produced in duplicate (test and control). Test cheeses were exposed to the Piophila casei colonization in a conditioned store room, while control cheeses were suitably protected. All the samples were analyzed at 0, 10, 30, 60 and 90 days from the production. The pH and aw, the chemical composition and the microbiological parameters (food safety and process hygiene criteria) were determined. The colonization was unhomogeneous between the batches: PO cheeses were more easily colonized and showed more intense proteolysis and lipolysis respect to PC cheeses. The microbiological parameters were strongly affected by the experimental process conditions. The authors discuss about the opportunity of a controlled production of &ldquo;casu marzu&rdquo; and the implications to the health of consumers.

Pategrás cheese as a suitable carrier for six probiotic cultures

The viability of five single-strain and one three-strain probiotic cultures was assessed during Pategrás cheese ripening. Probiotics were inoculated into cheese-milk after a pre-incubation step - intended to improve their survival - or directly as a lyophilised culture; control cheeses without probiotics were also obtained. pH of probiotic and control cheeses was similar, except in probiotic cheeses containing the strain Lb. acidophilus B or the mixed culture. In these cases, the probiotic cheeses were more acid than their respective control cheeses. All the probiotics tested maintained counts above 107 cfu/g during the shelf-life settled for the product. Strains of the Lb. casei group: Lb. paracasei, Lb. casei and Lb. rhamnosus reached and kept the highest cell concentration during cheese ripening, followed by Lb. acidophilus and bifidobacteria. The direct addition of the probiotic cultures was more efficient than their inoculation after a pre-incubation step, for all the probiotics assayed. We have provided evidence that support the use of Pategrás cheese as a performing food-based vehicle for probiotic bacteria.

Effect of Guar Gum on the Physicochemical, Thermal, Rheological and Textural Properties of Green Edam Cheese

In attempts to produce a low-fat cheese with a rheology and texture similar to that of a full-fat cheese, guar gum (within 0.0025–0.01%; w/v, final concentration) was added to low-fat milk. The obtained cheeses were characterised regarding their physicochemical, thermal, rheological and textural properties. Control cheeses were also produced with low and full-fat milk. The physicochemical properties of the guar gum modified cheeses were similar to those of the low-fat control. No significant differences were detected in the thermal properties (concerning the enthalpy and profile of water desorption) among all types of cheeses. The rheological behaviour of the 0.0025% modified cheese was very similar to the full-fat control. Overall, no trend was observed in the texture profile (hardness, cohesiveness, gumminess and elasticity) of the modified cheeses versus guar gum concentration, as well as in comparison with the control groups, suggesting that none of the studied polysaccharide concentrations simulated the textural functions of fat in Edam cheese.

Utilization of interesterified fat in the production of Turkish white cheese

The chemical, physicochemical, proteolysis, sensory, and texture characteristics of white cheeses made from interesterified fat were examined throughout ripening for 90 days. The water-soluble nitrogen based ripening indexes of cheeses increased throughout the ripening period. However, there were not large quantitative differences between the peptide profiles of the all cheese samples. Cheeses produced by using fully interesterified fat had higher values for hardness, chewiness, and gumminess than that of control cheese (p<0.05). The polyunsaturated to saturated fatty acid ratios of cheeses were increased due to the presence of interesterified fat. The cholesterol values of cheeses decreased at the rate of between 58.83–89.04% depending on interesterified fat addition. In the sensory analysis, similar scores were obtained for both the control cheese and the other cheeses. The results showed that interesterified fat in cheese production could be used to fully or partially replace the milk fat in cheese.

Study on the combined effects of essential oils on microbiological quality of Fior di Latte cheese

The effectiveness of three natural compounds in slowing down the deterioration of microbial quality of Fior di latte cheese is addressed. In particular, the control of the growth of spoilage microorganisms and the determination of the Microbiological Stability Limit (MAL) were the main goals. A Central Composite Design (CCD) strategy was adopted to highlight possible combined effects between three essential oils: sage and two types of lemon. Results showed an increase in the MAL value for all cheese samples packaged with the antimicrobial compounds, compared with the control cheese. Moreover, the combinations of the three essential oils indicated that the substances can act in a synergistic or antagonistic way, depending on their concentrations. In particular, a synergistic effect was evident when the three compounds were used at about 3000 ppm.

Microbiological, chemical, textural and sensory characteristics of Hispánico cheese manufactured using frozen ovine milk curds scalded at different temperatures

Hispánico cheese is a semi-hard variety, manufactured in Spain from a mixture of pasteurized bovine and ovine milk. To study one strategy for overcoming a seasonal shortage of ovine milk in summer and autumn, curds made from ovine milk, scalded at 32, 35 or 38 °C, were pressed for 30 min and frozen at −24 °C for 4 months. After thawing, they were added to fresh bovine milk curd for the manufacture of experimental Hispánico cheeses. Control cheese was made from a mixture of pasteurized bovine and ovine milk in the same (80:20) proportion. No significant effect of the addition of frozen ovine milk curd or scalding temperature was found for lactic acid bacteria counts, dry matter content, hydrophilic and hydrophobic peptides, 45 out of 65 volatile compounds, texture, and sensory characteristics throughout a 60-day ripening period. Differences between cheeses, of low magnitude and little practical significance, were found for pH value, aminopeptidase activity, proteolysis, free amino acids, free fatty acids, and the remaining 20 volatile compounds. Thus, the addition of frozen ovine milk curd to fresh bovine milk curd does not alter the main physicochemical and sensory characteristics of Hispánico cheese.

Genotypic identification of some lactic acid bacteria by amplified fragment length polymorphism analysis and investigation of their potential usage as starter culture combinations in Beyaz cheese manufacture

In this study, 2 different starter culture combinations were prepared for cheesemaking. Starter culture combinations were formed from 8 strains of lactic acid bacteria. They were identified as Lactococcus lactis ssp. lactis (2 strains), Lactobacillus plantarum (5 strains), and Lactobacillus paraplantarum (1 strain) by amplified fragment length polymorphism analysis. The effects of these combinations on the physicochemical and microbiological properties of Beyaz cheeses were investigated. These cheeses were compared with Beyaz cheeses that were produced with a commercial starter culture containing Lc. lactis ssp. lactis and Lc. lactis ssp. cremoris as control. All cheeses were ripened in brine at 4°C for 90 d. Dry matter, fat in dry matter, titratable acidity, pH, salt in dry matter, total N, water-soluble N, and ripening index were determined. Sodium dodecyl sulfate-PAGE patterns of cheeses showed that αS-casein and β-casein degraded slightly during the ripening period. Lactic acid bacteria, total mesophilic aerobic bacteria, yeast, molds, and coliforms were also counted. All analyses were repeated twice during d 7, 30, 60, and 90. The starter culture combinations were found to be significantly different from the control group in pH, salt content, and lactobacilli, lactococci, and total mesophilic aerobic bacteria counts, whereas the cheeses were similar in fat, dry matter content, and coliform, yeast, and mold counts. The sensory analysis of cheeses indicated that textural properties of control cheeses presented somewhat lower scores than those of the test groups. The panelists preferred the tastes of treatment cheeses, whereas cheeses with starter culture combinations and control cheeses had similar scores for appearance and flavor. These results indicated that both starter culture combinations are suitable for Beyaz cheese production.

Effect of high-pressure treatment on microbiology, proteolysis, lipolysis and levels of flavour compounds in mature blue-veined cheese

The effect of high-pressure (HP) treatment (400 MPa, 600 MPa) on ripening of mature 42-day-old Irish blue-veined cheese was studied. Counts of non-starter lactic acid bacteria, lactococci, yeasts, moulds, enterococci and total aerobic bacteria significantly decreased due to HP, with moulds being most sensitive and 600 MPa the most effective treatment. The levels of pH 4.6-soluble nitrogen and (12%) trichloroacetic acid-soluble nitrogen increased immediately after both HP treatments; however, after 28 days of storage, values were lower in HP-treated cheeses than in the control cheese. Urea-polyacrylamide gel electrophoresis showed increased breakdown of β-casein due to HP treatment at both 400 MPa and 600 MPa. Levels of free fatty acids were lower in HP-treated cheese than in the control, but not significantly so, and no significant changes could be observed in the level of flavour compounds of blue-veined cheese. Overall, HP treatment of blue-veined cheese reduced microbiological activity and decelerated proteolysis, with no statistically significant effects on development of flavour compounds. High-pressure treatment has been studied for the past 100 years; nevertheless, it was not applied in dairy industry, until recently, for a cheese spread. In this study, HP-induced inactivation of microbes and enzymes, which could arrest the ripening of high-quality mature (i.e., ripened) Irish farmhouse blue-veined cheese and thus extend shelf-life at optimal quality, was examined.

Effects of extruded linseed supplementation on n-3 fatty acids and conjugated linoleic acid in milk and cheese from ewes

The objective of this study was to assess the effects of dietary supplementation of extruded linseed on animal performance and fatty acid (FA) profile of ewe milk for the production of n-3 FA- and conjugated linoleic acid-enriched cheeses. A Manchega ewe flock (300 animals) receiving a 60:40 forage:concentrate diet was divided into 3 groups supplemented with 0, 6, and 12g of extruded linseed/100g of dry matter for the control, low, and high extruded linseed diets, respectively. Bulk and individual milk samples from 5 dairy ewes per group were monitored at 7, 14, 28, 45, and 60 d following supplementation. Manchego cheeses were made with bulk milk from the 3 treatment groups. Milk yield increased in dairy ewes receiving extruded linseed. Milk protein, fat, and total solids contents were not affected by linseed supplementation. Milk contents of α-linolenic acid increased from 0.36 with the control diet to 1.91% total FA with the high extruded linseed diet. Similarly, cis-9 trans-11 C18:2 rose from 0.73 to 2.33% and its precursor in the mammary gland, trans-11 C18:1, increased from 1.55 to 5.76% of total FA. This pattern occurred with no significant modification of the levels of trans-10 C18:1 and trans-10 cis-12 C18:2 FA. Furthermore, the high extruded linseed diet reduced C12:0 (−30%), C14:0 (−15%) and C16:0 (−28%), thus significantly diminishing the atherogenicity index of milk. The response to linseed supplementation was persistently maintained during the entire study. Acceptability attributes of n-3-enriched versus control cheeses ripened for 3 mo were not affected. Therefore, extruded linseed supplementation seems a plausible strategy to improve animal performance and nutritional quality of dairy lipids in milk and cheese from ewes.

Chemical changes that predispose smoked Cheddar cheese to calcium lactate crystallization

We have observed a high incidence of calcium lactate surface crystals on naturally smoked Cheddar cheese in the retail marketplace. The objective of this study was to identify chemical changes that may occur during natural smoking that render Cheddar cheese more susceptible to calcium lactate crystal formation. Nine random-weight (approximately 300g) retail-packaged samples of smoked Cheddar cheese were obtained from a commercial manufacturer immediately after the samples were smoked for about 6h at 20°C in a commercial smokehouse. Three similarly sized samples that originated from the same 19.1-kg block of cheese and that were not smoked were also obtained. Within 2 d after smoking, 3 smoked and 3 control (not smoked) samples were sectioned into 5 subsamples at different depths representing 0 to 2, 2 to 4, 4 to 6, 6 to 8, and 8 to 10mm from the cheese surface. Six additional smoked cheese samples were similarly sectioned at 4 wk and again at 10 wk of storage at 5°C. Sample sections were analyzed for moisture, l(+) and d(−) lactate, pH, and water-soluble calcium. The effects of treatment (smoked, control), depth from cheese surface, and their interactions were analyzed by ANOVA according to a repeated measures design with 2 within-subject variables. Smoked samples contained signficantly lower moisture and lower pH, and higher total lactate-in-moisture (TLIM) and water-soluble calcium-in-moisture (WSCIM) than control cheeses. Smoked samples also contained significant gradients of moisture, pH, TLIM, and WSCIM, with lower moisture and pH, and higher TLIM and WSCIM, occurring at the cheese surface. Gradients of moisture were still present in smoked samples at 4 and 10 wk of storage. In contrast, the pH, TLIM, and WSCIM equilibrated and showed no gradients at 4 and 10 wk. The results indicate that calcium and lactate in the serum phase of the cheese were elevated because of smoking, especially at the cheese surface immediately after smoking treatment, which presumably predisposes the smoked cheeses to increased susceptibility to calcium lactate surface crystallization.

Shelf life of Turkish whey cheese (Lor) under modified atmosphere packaging

In this study, the shelf life of Lor cheese stored under different atmosphere compositions was assessed and compared. Lor cheeses were held in four different atmospheres containing: vacuum packaging (VP), 40% CO2/60% N2, 60% CO2/40% N2 and 70% CO2/30% N2 (modified atmosphere packaging). Control cheeses were stored in air. All cheese samples were kept in the refrigerator at 4°C for 45 days and investigated for physicochemical, microbiological and sensory properties. The acidity index value was significantly higher ( P &lt; 0.05) in the control and vacuum packaged samples than in those stored for the same period under CO2. Microbiological results showed that modified atmosphere packaging delayed microbial growth compared with air and VP samples. Of the three modified atmospheres, gas mixtures 60% and 70% CO2 were the most effective for inhibition of growth of micro‐organisms. Sensory evaluation (odour and taste) results showed that Lor cheese packaged under modified atmosphere packaging (60% CO2/40% N2 and 70% CO2/30% N2 ) retained good characteristics for 45 days of storage, while vacuum and control samples were sensorily unacceptable after 10 days of storage.

Characterization of the free fatty acids profile of Pategrás cheese during ripening

This work compares the free fatty acids (FFA) profiles of Pategrás cheeses manufactured on the pilot scale, with and without the addition of probiotics. Total and FFA in milks and cheeses, respectively, were similar, indicating a nonselective release during ripening. Lipolysis was lo for control cheeses, but somewhat higher for those made in summer, probably because of an elevated psychrotrophic bacterial development. Probiotic bacteria remained highly viable during ripening and had an influence on FFA profiles. A simple sensory profiling of the cheeses showed no differences in flavour and taste and little evidence of treatment effects was found using univariate analysis. Nevertheless, multivariate analysis showed clear differences between probiotic and control products.

IMPACT OF SOME CARBOHYDRATE-BASE FAT REPLACERS ON THE LOW FAT MOZZARELLA-LIKE CHEESE CHARACTERISTICS

Two carbohydrate-base fat replacers were used to study the chemical and physical properties of low- fat Mozzarella cheese being made by using 1.5% fat cow's milk. The obtained curd was divided into seven equal parts, the first one was used as a control while the rest parts were treated with 4, 6 or 8% (w/w) of maize starch or rice starch such effects on the cheese properties were followed during storage of cheese at 4oC for six weeks . Only 4% of maize or rice starch treatments improved cheese meltability after one week of storage as compared with control cheese (82%and 23%), and the increases steadly continued as storage period advanced to reach the maximum after six weeks (177% and 105%) . Addition of 6% or 8% maize or rice starchs had bad or no impact on cheese meltability during the first two weeks of storage. All treatments had significant effect on the cheese contents of total solids, fat, protein and acidity .

Multivariate analysis of proteolysis patterns differentiated the impact of six strains of probiotic bacteria on a semi-hard cheese

The individual contribution of 6 strains of probiotic bacteria (3 of Lactobacillus acidophilus and 3 of the Lactobacillus casei group) to proteolysis patterns in a semi-hard cheese was assessed. Control cheeses (without probiotics) and 2 types of experimental cheeses (with the addition of probiotics either directly to milk or by a 2-step fermentation method) were manufactured. Cheeses containing Lb. acidophilus showed the most extensive peptidolysis, which was evidenced by changes in the peptide profiles and a noticeable increase of free amino acids compared with control cheeses. The strains of the Lb. casei group showed a lower contribution to cheese peptidolysis, which consisted mainly of free amino acid increase. Two-step fermentation improved peptidolytic activity for only one of the cultures of Lb. acidophilus tested. The addition of Lb. acidophilus strains into cheese may be suitable not only for their beneficial health effect but also for their influence on secondary proteolysis, consistent with acceleration of ripening and improved flavor formation.

Starter culture development for improving safety and quality of Domiati cheese

Eleven lactococci strains (sp. lactis and cremoris) were collected according to specific or selected characteristics for development of defined strain starter (DSS) to improve safety and nutritional quality of traditional and low salt Domiati cheese. Thirteen DSS; nisin-producing system or/and folate-producing strains were prepared. The behaviour of the strains in DSS was studied in milk and in two series of Domiati cheese; the first one made with 5% NaCl and salt tolerant strains, the second made with 3% NaCl and the control cheeses were made without starters. The population dynamics of strains and sensory evaluation of cheese corroborated the results in milk. All strains can grow well together and appeared to produce pleasant flavours, normal (typical) body and texture Domiati cheese. There was no apparent difference in cheese composition between cheeses in each series; the levels were within margins for composition of Domiati cheese. The levels of nisin (IU g −1) ranged from 204 to 324 IU g −1 in 3-months' cheeses. Folate concentration increased in cheeses made with DSS cultures than control and the level ranged from 5.5 to 11.1 μg 100 g −1 in cheeses after 3 months. All results revealed that selected DSS can be used for improving Domiati cheese.

CONTENT OF OMEGA-3, OMEGA-6 AND CHOLESTEROL INUF-WHITE SOFT CHEESE CONTAINING VEGETABLE AND MARINE OILS

UF soft cheese was made either traditionally or by replacing 50% of the milk fat with olive, sesame or marine oils, replacing 100% of the milk fat with coconut oil or replacing 75% of milk fat with corn oil to reach 15% fat in the final UF milk. Control cheese had the highest content of saturated fatty acids, while marine oil cheese had the lowest. Coconut oil cheese had the highest ratio of mono-unsaturated fatty acids. Corn oil had the highest polyunsaturated fatty acids. Marine oil cheese had the lowest Omega-6 content, while corn oil cheese had the highest. Corn oil cheese had the highest ratio of Omega-6/Omega-3, while marine oil cheese had the lowest. Control cheese had the highest cholesterol content and marine oil cheese had the lowest while corn oil, marine oil and coconut oil cheese had very low ratio (LDL/HDL).