Influence of adjunct use and cheese microenvironment on nonstarter bacteria in reduced-fat cheddar-type cheese

This study investigated population dynamics of starter, adjunct, and nonstarter lactic acid bacteria (NSLAB) in reduced-fat Cheddar and Colby cheese made with or without a Lactobacillus casei adjunct. Duplicate vats of cheese were manufactured and ripened at 7 degrees C. Bacterial populations were monitored periodically by plate counts and by DNA fingerprinting of cheese isolates with the random amplified polymorphic DNA technique. Isolates that displayed a unique DNA fingerprint were identified to the species level by partial nucleotide sequence analysis of the 16S rRNA gene. Nonstarter biota in both cheese types changed over time, but populations in the Colby cheese showed a greater degree of species heterogeneity. The addition of the L. casei adjunct to cheese milk at 10(4) cfu/ml did not completely suppress "wild" NSLAB populations, but it did appear to reduce nonstarter species and strain diversity in Colby and young Cheddar cheese. Nonetheless, nonstarter populations in all 6-mo-old cheeses were dominated by wild L. casei. Interestingly, the dominant strains of L. casei in each 6-mo-old cheese appeared to be affected more by adjunct treatment and not cheese variety.     

Nonstarter lactic acid bacteria biofilms and calcium lactate crystals in Cheddar cheese

A sanitized cheese plant was swabbed for the presence of nonstarter lactic acid bacteria (NSLAB) biofilms. Swabs were analyzed to determine the sources and microorganisms responsible for contamination. In pilot plant experiments, cheese vats filled with standard cheese milk (lactose:protein = 1.47) and ultrafiltered cheese milk (lactose:protein = 1.23) were inoculated with Lactococcus lactis ssp. cremoris starter culture (8 log cfu/mL) with or without Lactobacillus curvatus or Pediococci acidilactici as adjunct cultures (2 log cfu/mL). Cheddar cheeses were aged at 7.2 or 10°C for 168 d. The raw milk silo, ultrafiltration unit, cheddaring belt, and cheese tower had NSLAB biofilms ranging from 2 to 4 log cfu/100 cm². The population of Lb. curvatus reached 8 log cfu/g, whereas P. acidilactici reached 7 log cfu/g of experimental Cheddar cheese in 14 d. Higher NSLAB counts were observed in the first 14 d of aging in cheese stored at 10°C compared with that stored at 7.2°C. However, microbial counts decreased more quickly in Cheddar cheeses aged at 10°C compared with 7.2°C after 28 d. In cheeses without specific adjunct cultures (Lb. curvatus or P. acidilactici), calcium lactate crystals were not observed within 168 d. However, crystals were observed after only 56 d in cheeses containing Lb. curvatus, which also had increased concentration of d(−)-lactic acid compared with control cheeses. Our research shows that low levels of contamination with certain NSLAB can result in calcium lactate crystals, regardless of lactose:protein ratio.     

Hot topic: Geographical distribution and strain diversity of Lactobacillus wasatchensis isolated from cheese with unwanted gas formation

Lactobacillus wasatchensis, an obligate heterofermentative nonstarter lactic acid bacteria (NSLAB) implicated in causing gas defects in aged cheeses, was originally isolated from an aged Cheddar produced in Logan, Utah. To determine the geographical distribution of this organism, we isolated slow-growing NSLAB from cheeses collected in different regions of the United States, Australia, New Zealand, and Ireland. Seven of the cheeses showed significant gas defects and 12 did not. Nonstarter lactic acid bacteria were isolated from these cheeses on de Man, Rogosa, and Sharpe medium supplemented with ribose, a preferred substrate for Lb. wasatchensis. Identification was confirmed with 16S rRNA gene sequencing and the API50CH (bioMérieux, Marcy l'Etoile, France) carbohydrate panel. Isolates were also compared with one another by using repetitive element sequence-based PCR (rep-PCR). Lactobacillus wasatchensis was isolated only from cheeses demonstrating late-gas development and was found in samples from 6 of the 7 cheeses. This supports laboratory evidence that this organism is a causative agent of late gas production defects. The rep-PCR analysis produced distinct genetic fingerprints for isolates from each cheese, indicating that Lb. wasatchensis is found in several regions across the United States and is not a local phenomenon.     

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.     

Mini soft cheese as a simple model for biochemical studies on cheese-making and ripening

A new miniature cheese model obtained under controlled microbiological conditions was proposed, characterized and tested for reproducibility. Optimal heat treatment of cheesemilk was defined, as well as maximal ripening time. Miniature cheeses were obtained with batch pasteurized milk (65 °C, 30 min) and ripened at 5 °C. Lactic and nonlactic microbial populations were monitored by plate counts. Proteolysis was assessed by nitrogen fractions, electrophoresis and liquid chromatography, and a sniffing test was applied to evaluate aroma. Coliform bacteria decreased during ripening but moulds and yeasts increased up to 10⁴ cfu/g after 60 d, which defined the end of ripening period. Starter population remained constant during all ripening (10⁹ cfu/g), while nonstarter lactic acid bacteria increased from ∼10² to 10⁴ cfu/g. Soluble nitrogen levels at pH 4.6, in trichloracetic acid (0.73 mol/l) and in phosphotungtic acid (0.009 mol/l) were 151, 67, and 10 g/1000 g of the total nitrogen, respectively, after 60 d of ripening, which are usual values for soft cheeses. Proteolytic patterns as measured by electrophoresis were also similar to those of standard cheeses, as well as the aroma of the products. Peptide profiles revealed that the areas of most peaks increased with ripening time. The proposed model showed to be suitable for the production of mini cheese specimens for laboratory testing of cultures and enzymes in similar conditions to their real environment in the food matrix.     

A novel lactic acid bacterium for the production of high purity L-lactic acid, Lactobacillus paracasei subsp. paracasei CHB2121

Fermentation-derived lactic acid has several potential industrial uses as an intermediate carbon chemical and a raw material for biodegradable polymer. We therefore undertook the identification of a novel bacterial strain that is capable of producing high concentrations of lactic acid and has potential commercial applications. A novel L(+)-lactic acid producing bacterium, Lactobacillus paracasei subsp. paracasei CHB2121 was isolated from soil obtained near an ethanol production factory and identified by 16S rRNA gene sequence analysis and characterization using an API 50 CHL kit. L. paracasei subsp. paracasei CHB2121 efficiently produced 192 g/L lactic acid from medium containing 200 g/L of glucose, with 3.99 g/(L·h) productivity, and 0.96 g/g yield. In addition, the optical purity of the produced lactic acid was estimated to be 96.6% L(+)-lactic acid. The newly identified L. paracasei subsp. paracasei CHB2121 efficiently produces high concentrations of lactic acid, and may be suitable for use in the industrial production of lactic acid.     

Effect of Lactobacillus helveticus and Propionibacterium freudenrichii ssp. shermanii combinations on propensity for split defect in Swiss cheese

One of the least controlled defects in Swiss cheese is development of splits that appear during refrigerated storage after cheese is removed from the warm room. Such fissures, or cracks, in the body of the cheese can be as short as 1 cm, or long enough to span a 90-kg block. A 2 x 2 x 2 factorial experiment was used to determine the effect of different Lactobacillus helveticus/Propionibacterium freudenreichii ssp. shermanii starter culture combinations on the occurrence of split defect in Swiss cheese. Eights vats of cheese were made in summer and eight in winter. Each 90-kg block of cheese was cut into twenty-four 4-kg blocks and graded based on the presence of splits. Only small variations were found in the composition of cheeses made during the same season. There were no correlations between moisture, pH, fat, protein, calcium, lactose contents, D/L lactate ratio, or protein degradation that could be used to predict splits after 90 d of storage. However, cheese made in the summer had 2% higher moisture content and a greater prevalence of splits. There was a sixfold increase in amount of downgraded cheese between the best and worst culture combinations used during cheese manufacture. After 90-d storage, 14 to 90% of cheese had splits in the summer, and 1 to 6% in the winter. Split formation increased with time from 60 to 120 d of storage and extent of split formation was influenced by both the lactobacilli and propionibacteria cultures used.     

Galactose-positive adjunct cultures prevent gas formation by Paucilactobacillus wasatchensis WDC04 in a model gas production test

Gas production by obligatory heterofermentative lactic acid bacteria such as Paucilactobacillus wasatchensis is a sporadic problem in Cheddar cheese and results in undesired slits and cracks in the cheese. Growth of Pa. wasatchensis is not rapid, which makes investigations of gas production difficult to consistently execute. A primary objective of this study was to develop a model gas production test that could be used to investigate the effect of galactose and ribose utilization on gas production by Pa. wasatchensis and determine whether galactose-fermenting adjunct cultures could prevent gas formation. Paucilactobacillus wasatchensis WDC04 was inoculated at 10¹ to 10⁶ cfu/mL into carbohydrate-restricted MRS broth containing different ribose and galactose levels and incubated for up to 21 d at 23°C. Gas production in the broth was detected using a Durham tube inverted on a 6-cm-long capillary tube; cells were enumerated at 4, 8, and 12 d; and residual galactose was also measured. Gas production was sporadic except for when 10⁵ cfu/mL of Pa. wasatchensis WDC04 was inoculated into broth containing 0.3% ribose and 0.7% galactose. In those tubes, gas production was consistently observed after 8-d incubation, by which time galactose levels had decreased to 0.15%. Co-inoculation of Pa. wasatchensis WDC04 with as few as 10³ cfu/mL of a lactose-negative galactose-positive adjunct culture (Pediococcus acidilactici 23F, Lacticaseibacillus paracasei UW4, or Lactobacillus helveticus 7995) resulted in galactose depletion by d 4 and no observable gas production by d 12. With less galactose available to the slower-growing Pa. wasatchensis WDC04, its growth was limited to 10⁸ cfu/mL when any of the adjunct cultures was co-inoculated, compared with 10⁹ cfu/mL when grown on its own. We concluded that galactose-fermenting adjunct cultures have potential for preventing unwanted gas production in cheese by competition for resources and especially by removing the 6-carbon galactose before it can be utilized for energy by an obligatory heterofermentative lactobacilli such as Pa. wasatchensis and produce carbon dioxide.     

Short communication: characterization of microflora in Mexican Chihuahua cheese

This work was performed to identify the bacterial species present in 10 Chihuahua cheeses obtained from commercial producers in Mexico using 16S rRNA gene analysis. As expected, some of the agar media initially used for isolation were not very selective, supporting the growth of several unrelated bacterial species. Sequence analysis identified potential pathogens, including Escherichia coli and Staphylococcus aureus, in all raw milk samples and 2 pasteurized milk samples. Streptococcus thermophilus and Lactococcus lactis ssp. lactis were identified in 9 and 6 samples, respectively, and would serve as acidifying agents during cheese production. Lactobacilli were identified in all cheeses, with the most prevalent being Lactobacillus plantarum identified in 7 raw milk and 1 pasteurized milk cheeses. Leuconostoc mesenteroides and Streptococcus macedonicus were identified in 4 raw milk cheeses and both were present in all pasteurized milk samples, suggesting that they may play a role in the development of traditional Chihuahua cheese attributes.     

Effect of a bacteriocin‐producing strain of Lactobacillus paracasei on the nonstarter microflora of Cheddar cheese

In this study, the growth of chloramphenicol‐resistant bacteriocin‐sensitive indicator strain Lactobacillus casei DPC 2048^CM was evaluated in Cheddar cheese made with bacteriocin‐producing Lactobacillus paracasei DPC 4715. No suppression of growth of the indicator strain was observed in the cheese during ripening, and no bacteriocin production by L. paracasei DPC 4715 was detected by the well diffusion method in cheese and cheese extracts. The bacteriocin produced by L. paracasei DPC 4715 was sensitive to chymosin and cathepsin D, and it may have been hydrolysed by the rennet used for cheese manufacture or by indigenous milk proteases.     

Production and characterization of a tributyrin esterase from Lactobacillus plantarum suitable for cheese lipolysis

Lactobacillus plantarum is a lactic acid bacterium that can be found during cheese ripening. Lipolysis of milk triacylglycerols to free fatty acids during cheese ripening has fundamental consequences on cheese flavor. In the present study, the gene lp_1760, encoding a putative esterase or lipase, was cloned and expressed in Escherichia coli BL21 (DE3) and the overproduced Lp_1760 protein was biochemically characterized. Lp_1760 hydrolyzed p-nitrophenyl esters of fatty acids from C2 to C16, with a preference for p-nitrophenyl butyrate. On triglycerides, Lp_1760 showed higher activity on tributyrin than on triacetin. Although optimal conditions for activity were 45°C and pH 7, Lp_1760 retains activity under conditions commonly found during cheese making and ripening. The Lp_1760 showed more than 50% activity at 5°C and exhibited thermal stability at high temperatures. Enzymatic activity was strongly inhibited by sodium dodecyl sulfate and phenylmethylsulfonyl fluoride. The Lp_1760 tributyrin esterase showed high activity in the presence of NaCl, lactic acid, and calcium chloride. The results suggest that Lp_1760 might be a useful tributyrin esterase to be used in cheese manufacturing.     

A probiotic, Lactobacillus fermentum ME-3, has antioxidative capacity in soft cheese spreads with different fats

Our aim was to develop a prototype of a functional spread cheese containing both a specific probiotic and n-3 fatty acids and to analyze the viability of the probiotic and stability of n-3 fatty acids during 4 wk of shelf life. Lactobacillus fermentum ME-3 (Lf ME-3) isolated from a healthy Estonian child has been shown to have probiotic and antioxidative properties in several recent studies. In the current study this promising bacterial strain was combined with vegetable oils rich in nutritionally important α-linolenic acid and with unflavored cheese to obtain soft cheese spreads with different fat contents. Lactobacillus fermentum ME-3 survived well in all cheeses although the viable count did not increase during 4 wk of storage. The fatty acid composition of cheese triacylglycerols remained stable, whereas the profile of volatile compounds changed: hexanal and pentanal disappeared and the proportion of some alcohols increased. The changes in the profile of volatile compounds show the reductive power of Lf ME-3. A functional spread cheese containing n-3 fatty acids can be prepared with the probiotic Lactobacillus fermentum ME-3 strain leading to a reduced need for chemical anti-oxidants.     

A model to assess lactic acid bacteria aminopeptidase activities in Parmigiano Reggiano cheese during ripening

The aim of this work was to investigate in which phases of ripening of Parmigiano Reggiano cheese lactic acid bacteria aminopeptidases present in cheese extract could be involved in release of free amino acids and to better understand the behavior of these enzymes in physical-chemical conditions that are far from their optimum. In particular, we evaluated 6 different substrates to reproduce broad-specificity aminopeptidase N, broad-specificity aminopeptidase C, glutamyl aminopeptidase A, peptidase with high specificity for leucine and alanine, proline iminopeptidase, and X-prolyl dipeptidyl aminopeptidase activities releasing different N-terminal amino acids. The effects of pH, NaCl concentration, and temperature on the enzyme activities of amino acid β-naphthylamide (βNA)-substrates were determined by modulating the variables in 19 different runs of an experimental design, which allowed the building of mathematical models able to assess the effect on aminopeptidases activities over a range of values, obtained with bibliographic data, covering different environmental conditions in different zones of the cheese wheel at different aging times. The aminopeptidases tested in this work were present in cell-free Parmigiano Reggiano cheese extract after a 17-mo ripening and were active when tested in model system. The modeling approach shows that to highlight the individual and interactive effects of chemical-physical variables on enzyme activities, it is helpful to determine the true potential of an amino-peptidase in cheese. Our results evidenced that the 6 different lactic acid bacteria peptidases participate in cheese proteolysis and are induced or inhibited by the cheese production parameters that, in turn, depend on the cheese dimension. Generally, temperature and pH exerted the more relevant effects on the enzymatic activities, and in many cases, a relevant interactive effect of these variables was observed. Increasing salt concentration slowed down broad-specificity amino-peptidase C, glutamyl aminopeptidase A, proline iminopeptidase, and peptidase with high specificity for leucine and alanine. Interestingly, this variable did not affect broad-specificity aminopeptidase N and positively affected X-prolyl dipeptidyl aminopeptidase. The models elaborated varying pH, temperatures, and salt concentration and were a useful, low cost, and fast tool to understand the role of the main peptidases in the different phases of cheese ripening in relation to the major environmental factors influencing enzyme activity.     

Antagonistic action of Lactobacillus delbrueckii ssp. lactis RM2-5 toward spoilage organisms in cottage cheese

Cells of Lactobacillus delbrueckii ssp. lactis RM2-5 were added to cottage cheese stored at 7 degrees C in different amounts to determine if they would inhibit the growth of Pseudomonas fluorescens, also inoculated into the cheese samples. In addition, experiments were conducted in which no spoilage organisms were added to determine the effect of the lactobacilli on the natural background flora in the cottage cheese. For most experiments, as the numbers of lactobacilli increased, the numbers of spoilage organisms were lower than in the control on any given day of storage. In cheese inoculated with P. fluorescens, the numbers of spoilage organisms in the control had increased 5 log cycles by d 7, whereas the treatment containing the highest level of L. delbrueckii ssp. lactis RM2-5 (1.0 x 10(9) cfu/g) had not, and did not, increase over the course of the 21-d study. In the experiments where no spoilage organisms were added, lactobacilli significantly retarded the growth of gram-negative bacteria in the cheese. However, in these experiments, mold growth on the samples became a limiting factor during extended storage. The results of these experiments indicate that lactobacilli could be effective at helping control gram-negative spoilage bacteria in cottage cheese, thus potentially extending its shelf life.     

Resistance of two temperate Lactobacillus paracasei bacteriophages to high pressure homogenization, thermal treatments and chemical biocides of industrial application

Temperate bacteriophages ф iLp84 and ф iLp1308, previously isolated from mitomycin C-induction of Lactobacillus paracasei strains 84 and CNRZ1308, respectively, were tested for their resistance to several physical and chemical treatments applied in dairy industry. Long-term survival at 4 °C, −20 °C and −80 °C, resistance to either thermal treatments of 63 °C, 72 °C and 90 °C, high pressure homogenization (HPH, 100 MPa) or classic (ethanol, sodium hypochlorite and peracetic acid) and new commercial sanitizers, namely A (quaternary ammonium chloride), B (hydrogen peroxide, peracetic acid and peroctanoic acid), C (alkaline chloride foam), D (p-toluensulfonchloroamide, sodium salt) and E (ethoxylated nonylphenol and phosphoric acid), were determined. Phages were almost completely inactivated after eight months of storage at 25 °C, but viability was not affected at 4 °C, −20 °C or −80 °C. Both phages tolerated well HPH treatments. Phage iLp1308 showed higher thermal resistance than ф iLp84, but neither resisted 90 °C for 2 min. Best chemical inactivation was accomplished using peracetic acid or biocides A, C and E, whereas biocides B and D were completely ineffective. These results help to improve selection of chemical agents and physical treatments to effectively fight against phage infections in dairy plants.     

Proteolytic specificity of Lactobacillus delbrueckli subsp. bulgaricus influences functional properties of mozzarella cheese

Low-moisture part-skim Mozzarella cheeses were manufactured from 2% fat milk and aged for 21 d. Treatments included cheeses made with one of three different strains of Lactobacillus delbrueckii ssp. bulgaricus in combination with a single strain of Streptococcus thermophilus. A fourth, control treatment consisted of cheeses made with only S. thermophilus. Although total proteolytic ability of these strains, as indicated by the o-phthaldialdehyde analysis, was similar in each of the three strains of L. bulgaricus, these strains exhibited different proteolytic specificities toward the peptide, alpha(s1)-CN (f 1-23). On the basis of their alpha(s1)-CN (f 1-23) cleavage patterns and a previously described classification, these strains were assigned to the groups I, III, and V. The objective of this study was to investigate the influence of lactobacilli proteolytic systems, based on specificity toward alpha(s1)-CN (f 1-23), on functionality of part-skim Mozzarella cheese. Moisture, fat, protein, salt-in-moisture, and moisture in nonfat substances content of cheeses made with groups I, III, and V strain were similar. Control cheese had a lower moisture content than did other treatments. Significant differences were observed in functional properties between cheeses manufactured using groups III and V strains. Cheeses made with groups I and III strains were similar in their meltability, hardness, cohesiveness, melt strength, and stretch quality. Meltability and cohesiveness increased with age, while melt strength and stretch quality decreased with age for all cheeses. Additionally, HPLC showed that total peak areas of water-soluble peptides derived from cleavage of alpha(s1)-CN (f 1-23) by different strains of lactobacilli could be highly correlated to meltability and stretch characteristics of cheeses made with those strains.     

Growth,survival, and peptidolytic activity of Lactobacillus plantarum I91 in a hard-cheese model

In this work, we studied the growth, survival, and peptidolytic activity of Lactobacillus plantarum I91 in a hard-cheese model consisting of a sterile extract of Reggianito cheese. To assess the influence of the primary starter and initial proteolysis level on these parameters, we prepared the extracts with cheeses that were produced using 2 different starter strains of Lactobacillus helveticus 138 or 209 (Lh138 or Lh209) at 3 ripening times: 3, 90, and 180 d. The experimental extracts were inoculated with Lb. plantarum I91; the control extracts were not inoculated and the blank extracts were heat-treated to inactivate enzymes and were not inoculated. All extracts were incubated at 34°C for 21 d, and then the pH, microbiological counts, and proteolysis profiles were determined. The basal proteolysis profiles in the extracts of young cheeses made with either strain tested were similar, but many differences between the proteolysis profiles of the extracts of the Lh138 and Lh209 cheeses were found when riper cheeses were used. The pH values in the blank and control extracts did not change, and no microbial growth was detected. In contrast, the pH value in experimental extracts decreased, and this decrease was more pronounced in extracts obtained from either of the young cheeses and from the Lh209 cheese at any stage of ripening. Lactobacillus plantarum I91 grew up to 8 log during the first days of incubation in all of the extracts, but then the number of viable cells decreased, the extent of which depended on the starter strain and the age of the cheese used for the extract. The decrease in the counts of Lb. plantarum I91 was observed mainly in the extracts in which the pH had diminished the most. In addition, the extracts that best supported the viability of Lb. plantarum I91 during incubation had the highest free amino acids content. The effect of Lb. plantarum I91 on the proteolysis profile of the extracts was marginal. Significant changes in the content of free amino acids suggested that the catabolism of free amino acids by Lb. plantarum I91 prevailed in a weakly proteolyzed medium, whereas the release of amino acids due to peptidolysis overcame their catabolism in a medium with high levels of free amino acids. Lactobacillus plantarum I91 was able to use energy sources other than lactose to support its growth because equivalent numbers of cells were observed in extracts containing residual amounts of lactose and in lactose-depleted extracts. The contribution of Lb. plantarum I91 to hard-cooked cheese peptidolysis was negligible compared with that of the starter strain; however, its ability to transform amino acids is a promising feature of this strain.     

Technological and probiotic role of adjunct cultures of non-starter lactobacilli in soft cheeses

The influence of two cheese-isolated Lactobacillus strains on cheese composition, acceptability and probiotic capacity was assessed. Soft cheeses with and without the addition of Lactobacillus plantarum I91 or Lactobacillus paracasei I90 were prepared. Gross composition was assessed and secondary proteolysis was described by soluble fractions and free amino acids profiles. Acceptability was determined by a panel of 98 non-trained consumers. Cheeses harboring added Lactobacillus strains were also studied in vivo to evaluate their probiotic capacity. Gross composition of the cheeses was similar for control and treated (Lactobacillus-added) cheeses. Peptidolysis increased in cheeses with added lactobacilli, which was evidenced by a higher free amino acid content. Overall, the acceptability of the cheeses was good: 65%–80% of the consumers said that they “liked very much” or “liked” the cheeses. Cheeses with L. plantarum I91 showed the highest changes in composition and proteolysis and were the most accepted ones. On the contrary, composition of cheeses with L. paracasei I90 was similar to that of the controls, but these samples were less accepted than cheeses without lactobacilli. The oral administration of cheese containing L. plantarum I91 or L. paracasei I90 proved to be safe and able to enhance the number of IgA + cells in the small intestine lamina propria of mice. The use of selected strains of NSLAB exerted a technological and probiotic role: it contributed to the standardization of cheese quality and induced benefic health effects at the gut mucosa in vivo.