The effect of using an exopolysaccharide‐producing culture on the physicochemical properties of low‐fat and reduced‐fat Kasar cheeses

A mixed starter culture containing exopolysaccharide (EPS)‐producing strains of Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus was combined with Lactobacillus helveticus LH301 and used in the manufacture of low‐fat and reduced‐fat Kasar cheeses. For comparison, low‐fat (C10) and reduced‐fat (C20) cheeses were made using EPS‐producing (EPS⁺) starter strain and EPS‐non‐producing (EPS^?) starter strain. The physicochemical properties of the cheeses were assessed in terms of chemical composition, texture, microstructure and microbial content over 90 days. Cheeses made with EPS‐producing culture (EPS10 and EPS20) had lower protein contents than control cheeses with 10% and 20% fat in dry basis (C10 and C20). Scanning electron microscopy images showed that using EPS‐producing culture resulted in a less compact protein matrix and sponge‐like structure in the cheese samples. In general, cheeses made using EPS‐producing culture had lower total viable counts. This could be related to the reduced survivability of EPS‐producing cells in the cheese matrix during ripening due to autolysis ability.     

Isomaltooligosaccharide increases the Lactobacillus rhamnosus viable count in Cheddar cheese

Five batches of Cheddar cheese were manufactured containing different levels of isomaltooligosaccharide (IMO) and a probiotic strain of Lactobacillus rhamnosus to study the effect of IMO on the survival of starter lactococci and probiotic micro‐organisms, on proteolytic patterns, cheese composition and sensory properties. The cheese was exposed to conditions simulating those found in the gastrointestinal tract to evaluate the survival of Lb. rhamnosus. Results demonstrated that the addition of Lb. rhamnosus and IMO did not affect the main compositional variables of Cheddar cheese. The counts of starter culture and probiotic organisms increased in cheese which contained Isomaltooligosaccharide (Batches 3, 4 and 5) more than in the control (Batches 1 and 2) during the fermentation. The probiotic counts in fresh cheese (B‐4) was 9.23 log₁₀ cfu/g which was more than one log cycle greater than in the control (B‐2). The probiotic counts remained above 8 log₁₀ cfu/g at the end of the manufacturing process. Primary proteolysis was not affected by the addition of probiotic bacteria and IMO, but the level of secondary proteolysis was slightly higher compared with the control group. The addition of IMO improved the texture and sensory quality of the cheese and the probiotic bacterium had the same effect. Under conditions that simulated the gastrointestinal tract, the probiotic bacteria in cheese (B‐4) exhibited good survival and remained above the recommended 6–7 log₁₀ cfu/g.     

Influence of exopolysaccharide‐producing cultures on the volatile profile and sensory quality of low‐fat Tulum cheese during ripening

The objective of this investigation was to compare the composition and changes in the concentration of volatiles in low‐fat and full‐fat Tulum cheeses during ripening. Tulum cheese was manufactured from low‐ or full‐fat milk using exopolysaccharide (EPS)‐producing or non‐EPS‐producing starter cultures. A total of 82 volatile compounds were identified belonging to the following chemical groups: acids (seven), esters (21), ketones (14), aldehydes (six), alcohols (14) and miscellaneous compounds (20). The relative amounts of acids, alcohols and aldehydes increased in the cheeses made with EPS‐producing cultures during 90 days of ripening. Differences were found in the volatile profile of full‐fat Tulum cheese compared with the low‐fat variant, especially after 90 days of ripening. Exopolysaccharide‐producing cultures changed the volatile profile, and the EPS‐producing cultures including Streptococcus thermophilus + Lactobacillus delbrueckii subsp. bulgaricus + Lactobacillus helveticus (LF‐EPS2) produced cheese with higher levels of methyl ketones and aldehydes than the non‐EPS cultures. In the sensory analysis, full‐fat Tulum cheeses and the cheese produced with the EPS‐producing culture containing Lb. helveticus (LF‐EPS2) were preferred by the expert panel. It was concluded that the use of EPS‐producing starter cultures in the manufacture of low‐fat Tulum cheese had the potential to improve the flavour.     

Effects of Penicillium roqueforti and whey cheese on gross composition,microbiology and proteolysis of mould‐ripened Civil cheese during ripening

Four different types of mould‐ripened Civil cheese were manufactured. A defined (nontoxigenic) strain of a Penicillium roqueforti (SC 509) was used as the secondary starter with and without addition of the whey cheese (Lor); in parallel, secondary starter‐free counterparts were manufactured. Chemical composition, microbiology and proteolysis were studied during the ripening. The incorporation of whey cheese in the manufacture of mould‐ripened Civil cheese altered the gross composition and adversely affected proteolysis in the cheeses. The inoculated P. roqueforti moulds appeared to grow slowly on those cheeses, and little proteolysis was evident in all cheese treatments during the first 90 days of ripening. However, sharp increases in the soluble nitrogen fractions were observed in all cheeses after 90 days. Microbiological analysis showed that the microbial counts in the cheeses were at high levels at the beginning of ripening, while their counts decreased approximately 1–2 log cfu/g towards the end of ripening.     

Survival,growth characteristics and bioactive potential of Lactobacillus acidophilus in a soy‐based cream cheese

BACKGROUND: Soy‐based products have received much attention lately as dairy replacers and carriers for probiotics, without the cholesterol and lactose intolerance factors. We have previously developed a soy cream cheese product and would like to evaluate its suitability as a carrier for probiotic microorganisms. Soy cream cheese is commercially uncommon, while a probiotic soy cream cheese is yet to be available in the market. RESULTS: Five strains of probiotics were screened for their α‐galactosidase activity. Lactobacillus acidophilus FTCC 0291 showed the highest α‐galactosidase‐specific activity and was incorporated into soy cream cheese for a storage study of 20 days at 25 and 4 °C. L. acidophilus FTCC 0291 in soy cream cheese at both storage temperatures maintained a viability exceeding 10⁷ CFU g^?1 over storage. Oligosaccharide and reducing sugar analyses indicated that L. acidophilus FTCC 0291 was capable of utilizing the existing reducing sugars in soymilk and concurrently hydrolyzing the oligosaccharides into simpler sugars for growth. L. acidophilus FTCC 0291 also produced organic acids, leading to decreased pH. Under low pH and high organic acid concentration, the growth of total aerobes and anaerobes was significantly (P < 0.05) suppressed compared to the control. The hydrolysis of protein in soymilk produced essential growth factors such as peptides and amino acids that may have promoted the growth of L. acidophilus FTCC 0291 and the release of bioactive peptides with in vitro angiotensin I‐converting enzyme inhibitory activity. CONCLUSION: This study showed that soy cream cheese could be used as a carrier for probiotic bacteria, with potential antihypertensive property. Copyright © 2009 Society of Chemical Industry     

Dried Tomato‐Flavored Probiotic Cream Cheese with Lactobacillus paracasei

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

Preparation and properties of probiotic cheese high in conjugated linoleic acid content

The development of probiotic Ras cheese rich in conjugated linoleic acid (CLA) was investigated using probiotic Lactobacillus casei and Lactobacillus acidophilus starters. The cheeses were assessed for composition, proteolysis, fatty acids and fat stability, and microbiology during 3 months of ripening. The cheese made with Lb. casei and Lb. acidophilus retained high counts of the probiotic strains (～log 8) throughout storage. Ripening changes followed the normal pattern of this type of cheese during ripening. Ras cheese made with Lb. casei and Lb. acidophilus contained the highest CLA content (0.84% after 3 months) as compared to control and cheese fat had acceptable oxidative stability.     

Physicochemical and microbial properties of nanopowdered peanut sprout‐supplemented Caciocavallo‐like cheese during ripening

This study was carried out to investigate the physicochemical and microbial properties of nanopowdered peanut sprout‐supplemented Caciocavallo‐like cheese (NPSCC) during ripening at 14 °C for 6 weeks. The total phenol contents and lactic acid bacteria counts in NPSCC were significantly higher than those in the control, indicating that nanopowdered peanut sprout could potentially be used as a prebiotic and potential source of dietary antioxidants in the dairy products. Thiobarbituric acid values of the cheese were significantly decreased and the production of short‐chain free fatty was not significantly different when nanopowdered peanut sprout was added into the production of Caciocavallo‐like cheese.     

Preliminary screening of Bifidobacteria spp. and Pediococcus acidilactici in a Swiss cheese curd slurry model system: Impact on microbial viability and flavor characteristics

A Swiss cheese curd slurry model system was used as a preliminary screening method to determine the feasibility of the incorporation of probiotic bacteria (Bifidobacterium breve R0070, Bifidobacterium infantis R0033, Bifidobacterium longum R0175, and Pediococcus acidilactici R1001) into Swiss cheese. The cheese curd was inoculated with probiotic bacteria (8.0 log₁₀ cfu g⁻¹) and ripened anaerobically for 0, 7, and 10 days at 37 °C. Following ripening, counts of the probiotic bacteria increased to 9–10 log₁₀ cfu g⁻¹, with no significant difference in the viability of the four probiotic bacteria. Viable populations of Swiss cheese background microflora in the presence of each probiotic culture were comparable with the control. Ripening time, and to a lesser extent probiotic treatment had a significant effect on the content of several volatile flavor compounds. Similarly, ripening time contributed to a significant increase in the content of a majority of the free amino acids. The study demonstrated the feasibility of the incorporation of probiotic bacteria into Swiss cheese to produce a functional food.     

Survival of micro‐organisms and organic acid profile of probiotic Cheddar cheese from buffalo milk during accelerated ripening

The study aimed to assess the impact of ripening at elevated temperatures on the survival of probiotic micro‐organisms and production of organic acids in Cheddar cheese. Cheese was manufactured from buffalo milk using lactococci starters along with different probiotic bacteria (Lactobacillus acidophilus LA‐5, Bifidobacterium bifidum Bb‐11 and Bifidobacterium longum BB536) as adjunct cultures. The cheeses were ripened at 4–6 °C or 12–14 °C for 180 days and examined for composition, organic acids and microbial survival. The production of organic acids was accelerated at 12–14 °C when compared to normal ripening temperatures. The probiotic bacteria increased production of lactic and acetic acids, compared to cheese made with lactococci alone. The survival of the mesophilic starters was significantly (P < 0.05) reduced in all the cheese samples ripened at the higher temperature. However, the probiotic bacteria remained viable (>7.0 log₁₀ cfu/g) throughout the 180 days of ripening, irrespective of temperature. It was concluded that Cheddar containing additional probiotic cultures can effectively be ripened at elevated temperatures without any adverse effects.     

Cream cheese as a symbiotic food carrier using Bifidobacterium animalis Bb‐12 and Lactobacillus acidophilus La‐5 and inulin

The stability of cream cheeses as a symbiotic food carrier, through supplementation with different concentrations of probiotic bacteria Bifidobacterium animalis Bb‐12 and Lactobacillus acidophilus La‐5 and the prebiotic ingredient inulin was investigated. Physicochemical parameters, pH values, total solids, fat and protein levels and the viable counts of the starter lactic culture Streptococcus thermophilus and probiotic cultures, were carried out at 1, 15, 30 and 45 days of refrigerated storage (8 ± 0.5 °C). Different physicochemical characteristics were observed in all formulations. S. thermophilus showed good viability in all the trials (6.66–9.38 log cfu/g), whereas B. animalis remained above 6 log cfu/g in all the trials during the period evaluated. However, L. acidophilus showed an accentuated decline, registering values of 3.1 log cfu/g at the end of the period studied. The results suggested that cream cheese was an adequate food matrix for supplementation with probiotic bacteria, in particular B. animalis, and the prebiotic ingredient, showing potential as a symbiotic food.     

Probiotic lactobacilli in a semi-soft cheese survive in the simulated human gastrointestinal tract

In this study, probiotics Lactobacillus acidophilus NCFM and Lactobacillus rhamnosus HN001 in cheese were studied using models simulating the human gastrointestinal tract with the aim of investigating whether the cheese matrix affected the survival and metabolic properties of these probiotic strains. Probiotics in cheese survived in the simulated upper gastrointestinal tract model, and numbers of L. acidophilus, L. rhamnosus and total lactobacilli were increased in the colonic fermentation simulations of the probiotic cheese when compared with the non-probiotic cheese used as a control. The cheese matrix also beneficially affected cyclooxygenase-gene expression of colonocytes in a cell culture model. Freeze-dried probiotics, which were also analysed in the colonic simulator, showed similar changes in Lactobacillus numbers, although gave a stronger increase and also affected other microbial groups. These results indicate that the probiotic microbes in cheese survive in the gastrointestinal tract and that the cheese matrix does not seem to affect the probiotic survival.     

Effect of Penicillium roqueforti and incorporation of whey cheese on volatile profiles and sensory characteristics of mould‐ripened Civil cheese

In this study, four different types of mould‐ripened Civil cheese were manufactured. A defined (nontoxigenic) strain of a Penicillium roqueforti (SC 509) was used as secondary starter for the manufacture of mould‐ripened Civil cheese with and without addition of the whey cheese Lor; in parallel, secondary starter‐free counterparts were manufactured. A total of 83 compounds were identified. Ketones, alcohols and esters were the principal classes of volatile components. Principal component analysis of the headspace volatiles grouped cheeses by age and type. P. roqueforti inoculated cheese was clearly separated from the other cheeses at 180 days of ripening, and these cheeses were characterised with high levels of ketones (e.g., 2‐butanone, 2‐heptanone). Differences in the panel scores between the cheese samples were not significant during the first stage of ripening (up to 60 days); as ripening proceeded, these differences were become evident and P. roqueforti inoculated cheeses received higher scores than others. Addition of Lor in the manufacture of mould‐ripened Civil cheese caused lower points by the sensory panel, and the cheese inoculated with P. roqueforti and Lor‐free was the best type of mould‐ripened Civil cheese. The results showed that the use of P. roqueforti in the manufacture of mould‐ripened Civil cheese has significant impact on the volatile profiles and sensory attributes.     

Use of Taiwanese ropy fermented milk (TRFM) and Lactococcus lactis subsp. cremoris isolated from TRFM in manufacturing of functional low-fat cheeses

Abstract: The purpose of this study was to manufacture new functional low‐fat cheeses using Taiwanese ropy fermented milk (TRFM) and Lactococcus lactis subsp. cremoris strains isolated from TRFM. After 28 d of ripening and storage, the viable populations of lactic acid bacteria (LAB) in the low‐fat cheeses made with L. lactis subsp. cremoris TL1 (TL1), L. lactis subsp. cremoris TL4 (TL4), and TRFM still maintained above 10⁸ CFU/g. The low‐fat cheeses made with TL1 and TRFM showed higher moisture contents than the cheeses made with TL4, full‐fat, and low‐fat cheese controls. The low‐fat cheeses made with TL1 and TL4 had higher customer preferential scores similar to full‐fat cheese control in the sensory evaluation. Additionally, the low‐fat cheeses fermented with TL1, TL4, and TRFM for 4 h had higher 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) free radical‐scavenging and ferrous ion‐chelating abilities than the cheeses fermented with the starters for 8 h, full‐fat, and low‐fat cheese controls. A better angiotensin‐converting enzyme (ACE) inhibition activity was also observed in the low‐fat cheeses made with TL1, TL4, and TRFM than that in the full‐fat and low‐fat cheese controls during ripening and storage period. Practical Application: As health‐conscious consumers continue to seek low‐fat alternatives in their diets, there remain strong interests for the dairy industry to develop low‐fat cheeses to meet the demands. This study clearly demonstrated that the low‐fat cheeses fermented with TL1 for 4 h showed a better overall acceptability and possessed antioxidative abilities and ACE inhibitory activities than other cheeses tested in this study. By improving its flavor and investigating the possible mechanisms of its functionalities in the future, this low‐fat cheese might possibly be commercialized and give a positive impact on cheese consumption in the future.     

Digestive protection of probiotic Lacticaseibacillus rhamnosus in Ricotta cheese by monoglyceride structured emulsions

This research aimed at studying the potential use of monoglyceride (MG) structured emulsions (MSEs) as delivery and protective systems for probiotic bacteria in Ricotta cheese. To this purpose, a low-fat commercial Ricotta cheese was added with MSEs formulated with milk, as water phase, and sunflower oil (MSE-SO) or anhydrous milk fat (MSE-AMF), as lipid phase. A commercial whole milk Ricotta cheese (W-RC) was considered as reference. A probiotic Lacticaseibacillus rhamnosus strain was inoculated as free cells in W-RC or embedded into the MSEs and added to the low-fat Ricotta at the same reference fat content. After physico-chemical characterisation, L. rhamnosus viability and sample destructuring behaviour upon in vitro digestion were evaluated. At the end of in vitro digestion, both W-RC and sample containing MSE-SO were unable to protect cells. By contrast, sample with AMF ensured a sufficient probiotic viability, even after 14 days of storage at 4 °C. This result was attributed to system composition and structure. During the gastric phase, the presence of caseins and MG-AMF mixed structures induced the formation of clots, entrapping and protecting cells against the acidic pH of the stomach, as confirmed by confocal micrographs and particle size. During the intestinal phase, cell viability was guaranteed by the formation of mixed micelles promoted by MG. It was demonstrated that microbial cells located near MG structures where they found protection.     

Proteolysis texture and microstructure of low‐fat Tulum cheese affected by exopolysaccharide‐producing cultures during ripening

The objective of the study was to determine the effects of exopolysaccharide (EPS)‐producing or non‐EPS‐producing starters on proteolysis, physical and microstructural characteristics of full‐fat or low‐fat Tulum cheeses during ripening. For this purpose, Tulum cheese was manufactured using full‐ or low‐fat milk with EPS‐producing and non‐EPS‐producing starter cultures. Chemical composition, proteolysis, texture profiles and microstructure of the cheeses were studied during 90 days of ripening. Urea‐PAGE of water‐insoluble and RP‐HPLC peptide profiles of water‐soluble fractions of the cheeses showed that the use of starters resulted in different degradation patterns in all cheeses during ripening. Although β‐casein exhibited similar degradation patterns in all cheeses, small differences are present in α_s1‐casein degradation during ripening. Reducing fat in Tulum cheese changed the RP‐HPLC peptide profile of the cheeses. The use of EPS‐producing cultures improved the textural characteristics and changed the microstructure and proteolysis of low‐fat Tulum cheese.     

Coalho Cheese Made with Protease from Thermomucor indicae‐seudaticae N31: Technological Potential of the New Coagulant for the Production of High‐Cooked Cheese

The aim of this study was to explore the use of a new coagulant from Thermomucor indicae‐seudaticae N31 for the manufacture of a high‐cooked starter‐free cheese variety, by evaluating its physicochemical and functional characteristics in comparison to cheeses made with a traditional commercial coagulant. Coalho cheese was successfully produced with the new protease as it exhibited comparable characteristics to the one produced using the commercial enzyme: pH behavior during manufacture; cheese composition; protein and fat recovery; and cheese yield. In addition, during storage, melting was low and not affected by storage time; the increase of TCA 12% soluble nitrogen (% of total nitrogen) was lower than half of that of pH 4.6 soluble nitrogen (% of total nitrogen); concentration of β‐CN significantly decreased, whereas α_s1‐CN concentration was not affected by storage time.     

The effect of three different ripening/storage conditions on the distribution of selected parameters in individual parts of Dutch‐type cheese

The aim of the study was (i) to detect changes of dry matter, NaCl and twenty‐two free amino acids contents, pH and levels of selected microorganisms in four layers of cheese (from edge to core) during ripening and storage period and (ii) to describe the changes of the above‐mentioned parameters caused by early relocation of cheese from optimum ripening conditions to refrigeration temperatures. The number of mesophilic aerobic and facultative anaerobic bacteria and lactic acid bacteria differed significantly (P < 0.05) during the experiment dependent on the analysed layer and ripening/storage conditions. The free amino acid content differed significantly in individual analysed layers of cheese and also according to individual ripening/storage conditions. The highest content of free amino acids was found in samples stored at optimal ripening temperatures. Cheese hardness was also analysed and the lowest one was detected in samples ripened under optimal temperatures for the whole period. Early release of cheeses into storage rooms with lower temperature significantly affected properties of these products.     

Effects of Mentha longifolia L. essential oil and Lactobacillus casei on the organoleptic properties and on the growth of Staphylococcus aureus and Listeria monocytogenes during manufacturing,ripening and storage of Iranian white‐brined cheese

This research evaluated the effects of Mentha longifolia L. essential oil (EO) in concentrations 0, 50, 150 and 300 ppm and Lactobacillus casei (10⁸–10⁹ CFU/mL) on the growth of Staphylococcus aureus and Listeria monocytogenes during the manufacturing, ripening and storage of Iranian white‐brined cheese. The growth of the two pathogens was significantly reduced (P < 0.01) by both EO concentrations ≥50 ppm and probiotic and their combination in the standard manufacturing and storage process conditions of the cheese. Furthermore, the treatment containing 150 ppm of this EO combined with probiotic had a favourable inhibitory effect on the growth of two pathogenic micro‐organisms and also was the most appropriate treatment in sensory assessment. The synergistic effects of the above‐mentioned concentration level between the essential oil and probiotic were significant compared to other treatments, including essential oil and probiotic only. Thus, a lower concentration of this EO can be used when it is combined with this probiotic.