The effect of using different probiotic cultures on conjugated linoleic acid (CLA) concentration and fatty acid composition of white pickle cheese

Pickle white cheeses were produced from whole milk with five different probiotic cultures (Enterococcus faecium, Lactobacillus paracasei, Bifidobacterium longum, Bifidobacterium bifidum and Lactobacillus acidophilus). Conjugated linoleic acid (CLA) content of cheeses ranged from 3.52 to 3.92?mg/g. Probiotic differences and storage process have not affected the CLA contents of the samples statistically. There was no correlation between the CLA content of all probiotic cheeses and saturated fatty acids. A positive correlation between the CLA and linoleic acid contents of L. paracasei and L. acidophilus cheeses was observed.     

Development and quality of a Brazilian semi-hard goat cheese (coalho) with added probiotic lactic acid bacteria

The effects of the addition of different strains of lactic acid bacteria on different quality parameters of a Brazilian goat semi-hard cheese (coalho) were assessed during 7 days of storage (10°C) as follows: Control, Lactobacillus lactis subsp. lactis and L. lactis subsp. cremoris (standard); C2, L. acidophilus; C3, L. paracasei; C4, Bifidobacterium lactis; and C5, L. acidophilus, L. paracasei and B. lactis. There were no differences for the proteolysis index and depth of proteolysis among the assessed cheeses. The cheeses presented increase in hardness, gumminess and chewiness during the storage. Regarding the ability to melt, all evaluated cheeses showed a reduction in diameter. Cheeses presented high luminosity with predominance of the yellow component; and number of lactic bacteria greater than 10⁶–10⁷ cfu/g during the 7 days of storage. C5 had better sensory scores in the acceptance test, purchase intention and preference ranking test. Coalho goat cheese could be a potential carrier of probiotic lactic acid bacteria.     

The effects of probiotics and prebiotics on the fatty acid profile and conjugated linoleic acid content of fermented cow milk

Abstract

The ability of probiotic bacteria (Lactobacillus acidophilus La5 and Bifidobacterium animalis Bb12), to produce conjugated linoleic acid (CLA) in association with Streptococcus thermophilus and Lb. bulgaricus during milk fermentation has been evaluated in this study. Pasteurized cow milk and infant formula were used. Infant formula was selected for its high linoleic acid content, for being a source of CLA and for its prebiotic compounds, e.g. galacto-oligosaccharides. The microorganisms were not able to increase the CLA content of the fermented products under the given experimental conditions. No statistically significant differences (p?>?0.05) occurred between the CLA content in milk and the fermented samples. The CLA contents of 10 commercial fermented milk products were determined. The highest CLA content was observed in fermented milk containing only Str. thermophilus and Lb. bulgaricus.     

Chemical characteristics,fatty acid compositions,conjugated linoleic acid contents and cholesterol levels of some traditional Turkish cheeses

The chemical characteristics, fatty acid and conjugated linoleic acid (CLA) contents and cholesterol levels of some traditional Turkish cheeses that are consumed mostly in Turkey were determined in this study. The fatty acid and cholesterol contents and CLA amount of cheeses were analysed as methyl esters by gas chromatography. The aim of this study was to determine the nutritional profile of some Turkish cheeses produced by traditional methods. The major fatty acids of the cheeses were palmitic acid (C_16:0) and oleic acid (C_18:1). The saturated fatty acid content of samples changed between 60.80% and 76.57%, while the monounsaturated fatty acid content ranged from 21.42% to 34.05% and the polyunsaturated fatty acid content was between 1.47% and 3.59%. The CLA contents of the cheeses ranged from 0.44 to 1.04 g/100 g in fat. The cholesterol levels of the samples were determined as 44.6–147.69 mg/100 g in cheese.     

Probiotic mixture containing Lactobacillus spp. and Bifidobacterium spp. attenuates 5-fluorouracil-induced intestinal mucositis in mice

Abstract

Lactobacillus spp. and Bifidobacterium spp. was used to protect against gastrointestinal disorders. The present study evaluated the effects of probiotic mixture (PM) containing Lactobacillus spp. and Bifidobacterium spp. on intestinal mucositis induced by 5-fluorouracil (5-FU). Swiss male mice (25–30?g) were treated with 5-FU (450?mg/kg, ip) and were orally administered (PM). Probiotic mixture 1 (PM-1) is a mixture of two probiotics (Lactobacillus acidophilus and Bifidobacterium lactis) and probiotic mixture 2 (PM-2) is a mixture of four probiotics (Lactobacillus acidophilus, Lactobacillus paracasei, Lactobacillus rhamnosus, and Bifidobacterium lactis). PM-1 and PM-2 decreased histopathological scores in the duodenum and jejunum after mucositis. PM-2 attenuated 5-FU-induced weight loss. On the other hand, PM-1 did not exert a significant effect on weight loss. Both probiotics mixture increased the villus/crypt ratio in all intestinal segments, increased GSH levels in the duodenum and jejunum, and reduced the MDA, MPO, TNF-α, and IL-6 levels in the duodenum, jejunum, and ileum. PM-2 attenuated the delay in gastric emptying. PM-1 and PM-2 prevented epithelial injury in intestinal mucositis by 5-FU, demonstrating the potential use of these probiotics as therapeutic agents against intestinal mucositis.     

Chemical characteristics, fatty acid compositions, conjugated linoleic acid contents and cholesterol levels of some traditional Turkish cheeses

The chemical characteristics, fatty acid and conjugated linoleic acid (CLA) contents and cholesterol levels of some traditional Turkish cheeses that are consumed mostly in Turkey were determined in this study. The fatty acid and cholesterol contents and CLA amount of cheeses were analysed as methyl esters by gas chromatography. The aim of this study was to determine the nutritional profile of some Turkish cheeses produced by traditional methods. The major fatty acids of the cheeses were palmitic acid (C(16:0)) and oleic acid (C(18:1)). The saturated fatty acid content of samples changed between 60.80% and 76.57%, while the monounsaturated fatty acid content ranged from 21.42% to 34.05% and the polyunsaturated fatty acid content was between 1.47% and 3.59%. The CLA contents of the cheeses ranged from 0.44 to 1.04 g/100 g in fat. The cholesterol levels of the samples were determined as 44.6-147.69 mg/100 g in cheese.     

Bioproduction of conjugated linoleic acid by probiotic bacteria occurs in vitro and in vivo in mice

Probiotics have been shown to reduce the incidence of colon cancer in animal models. The mechanisms responsible for this activity are poorly defined. Conjugated linoleic acids (CLA) are a group of isomers of linoleic acid (LA) possessing anti-inflammatory and anticarcinogenic properties, which can be produced from LA by certain bacterial strains. In this study, the ability of probiotic bacteria to exert anticarcinogenic effects through the production of CLA was assessed. Incubation of probiotic bacteria (VSL3, Lactobacillus acidophilus, L. bulgaricus, L. casei, L. plantarum, Bifidobacterium breve, B. infantis, B. longum, and Streptococcus thermophilus) in the presence of LA yielded CLA production as measured by gas chromatography. Conditioned medium, containing probiotic-produced CLA, reduced viability and induced apoptosis of HT-29 and Caco-2 cells, as assessed by MTT assay and DNA laddering, respectively. Western blotting demonstrated an increased expression of PPARgamma in cells treated with conditioned medium compared with LA alone. Incubation of murine feces with LA after administering VSL3 yielded 100-fold more CLA than feces collected prior to VSL3 feeding. This study supports a role for supplemental probiotics as a strategy both for attenuating inflammation and for preventing colon cancer.     

Conjugated linoleic acid and vaccenic acid contents in cheeses: An overview from the literature

The conjugated linoleic acids (CLA) and vaccenic (C18:1 trans-11; C18:1 t-11) acid contents of cheeses have been reported in many publications. Data on both constituents were collected from 58 references and statistically analyzed. The CLA content of cheeses varied widely from 0.050 to 2.86 g 100 g⁻¹ total fatty in the published data. The type of milk, dietary feeding of lactating animals, geographical origin and year of publication had significant effects on CLA content of cheeses. Cheeses were grouped into hard, semi-hard, soft, moldy and processed. Differences in the CLA content of these groups were not significant. Also, cheese ripening had no significant effect of the CLA content in cheese. Positive correlations were found in the CLA and C18:1 t-11 contents of cow milk and sheep milk cheeses.     

Different level of conjugated linoleic acid (CLA) in dairy products from Italy

A survey was carried out to determine the content of conjugated linoleic acid (CLA) in various dairy products. The only detected CLA isomer was cis-9trans-11 linoleic acid. Commercial samples of yoghurt, fermented milk and cheese were analyzed: 16 standard yoghurts, 6 organic yoghurts, 8 mountain pasture yoghurts, 5 sheep yoghurts, 8 probiotic yoghurts, 8 fermented milk samples, 6 fermented milk samples from mountain pastures, 30 cow cheeses (9 Alpine cheeses, 8 Swiss Emmental, 8 Fontina Valdostana, 5 Grana Padano and Parmigiano Reggiano), 12 ewe cheeses (Pecorino) and 8 goat cheeses. The fatty acid composition and fat content were also assessed. Fontina Valdostana had the highest amount of CLA (8.11 mg/g fat), followed by Pecorino cheese (7.77 mg/g fat), Swiss Emmental (7.66 mg/g fat) and sheep yoghurt (6.92 mg/g fat). High levels of CLA were also found in fermented milk and yoghurt of mountain pasture and organic yoghurt (6.15, 6.06 and 6.05 mg/g fat, respectively). The animal diet, specific characteristics of the milk used in manufacturing, with special reference to the species and CLA content of the milk, processing and production methods play an important role in setting the CLA levels in dairy products.     

A comparative study of fatty acid composition and CLA concentration in commercial cheeses

A total of 52 Italian and French commercial cheeses were analysed for fatty acid composition and conjugated linoleic acid (CLA) concentration. The cheeses were first grouped according to the ruminant species of the milk used in manufacturing, then according to the following criteria: (1) cheeses obtained from milk of the same ruminant species but using different production technologies; (2) cheeses produced from milk of different ruminant species but through similar cheesemaking processes. Comparative studies of fatty acid composition and CLA levels in the different cheese classes were carried out. In our study, the arrangement of the ruminant species according to the increasing CLA concentration in cheese was: goat = cow < sheep. Sheep cheeses had the highest levels of CLA (9.86 mg/g fat), α-linolenic acid (0.75%) and trans-vaccenic acid (1.63%), and the lowest contents of linoleic acid (1.80%) and oleic acid (16.83%). The comparison of cheeses obtained from milk of the same ruminant species but through different production technologies reported statistically significant differences in the fatty acid profiles that could be due to a different degree of lipolysis in the cheeses compared. Nevertheless, statistically significant differences in CLA concentration were not found; this suggests that the factors involved in the cheesemaking process generally do not affect the CLA content in milk fat.     

An Integrated Analytical Approach for the Characterization of Probiotic Strains in Food Supplements

Research surrounding health benefits from probiotics is becoming popular because of the increasing demand for safer products with protective and therapeutic effects. Proven benefits are species- or genus-specific; however, no certified assays are available for their characterization and quantification at the strain level in the food supplement industry. The objective of this study was to develop a strain-specific Real-time quantitative polymerase chain reaction (RT-qPCR)-based method to be implemented in routine tests for the identification and quantification of Bifidobacterium longum, Bifidobacterium animalis spp. lactis, Lactobacillus paracasei, Lactobacillus rhamnosus, Lactobacillus casei, Bifidobacterium breve, Lactobacillus acidophilus, Lactobacillus plantarum, and Lactobacillus helveticus, starting from a powder mixture of food supplements. The method optimization was carried out in combination with flow cytometry to compare results between the two strategies and implement the analytical workflow with the information also regarding cell viability. These assays were validated in accordance with the International Council for Harmonization of Technical Requirements for Pharmaceuticals for Human Use (ICH) criteria using the plate count enumeration as the gold standard reference. Briefly, probiotic DNAs were extracted from two powder food supplements. Strain-specific primers targeting unique sequence regions of 16S RNA were identified and amplified by RT-qPCR. Primers were tested for specificity, sensitivity, and efficiency. Both RT-qPCR and flow-cytometry methods described in our work for the quantification and identification of Lactobacillus and Bifidobacterium strains were specific, sensitive, and precise, showing better performances with respect to the morphological colony identification. This work demonstrated that RT-qPCR can be implemented in the quality control workflow of commercial probiotic products giving more standardized and effective results regarding species discrimination.     

Probiotics Lactobacillus rhamnosus GG,Lactobacillus acidophilus Suppresses DMH-Induced Procarcinogenic Fecal Enzymes and Preneoplastic Aberrant Crypt Foci in Early Colon Carcinogenesis in Sprague Dawley Rats

Diet makes an important contribution to colorectal cancer (CRC) risk implying risks for CRC are potentially reducible. Therefore, the probiotics have been suggested as the prophylactic measure in colon cancer. In this study, different probiotics were used to compare their protective potential against 1,2 dimethylhydrazine dihydrochloride (DMH)-induced chemical colon carcinogenesis in Sprague Dawley rats. Animals belonging to different probiotic groups were fed orally with 1 × 10⁹ lactobacilli daily for 1 week, and then a weekly injection of DMH was given intraperitoneally for 6 wks with daily administration of probiotic. Lactobacillus GG and L.acidophilus + DMH-treated animals had maximum percent reduction in ACF counts. A significant decrease (P < 0.05) in fecal nitroreductase activity was observed in L.casei + DMH and L.plantarum + DMH-treated rats whereas β-glucuronidase activity decreased in L.GG + DMH and L.acidophilus + DMH-treated rats. Animals treated with Bifidobacterium bifidum + DMH had significant decreased β-glucosidase activity. However, not much difference was observed in the colon morphology of animals belonging to various probiotic + DMH-treated rats compared with DMH-treated alone. The results indicated that probiotics, L.GG, and L.acidophilus can be used as the better prophylactic agents for experimental colon carcinogenesis.     

Cell-free extracts of Lactobacillus acidophilus and Lactobacillus delbrueckii display antiproliferative and antioxidant activities against HT-29 cell line

Abstract

Many beneficial effects of probiotic Lactobacilli on cancer prevention and therapy were previously presented. So finding probiotics with proapoptotic activities is a promising approach for cancer drug discovery. Here, the antiproliferative and antioxidant activities of cell-free extracts of Lactobacillus acidophilus and Lactobacillus delbrueckii on HT-29 cell line were evaluated employing MTT and DPPH assays. The induction of apoptosis was assessed by Hoechst staining and flow cytometry analysis which was further confirmed by expression analysis of BCL-2, BAX, caspase-3, caspase-8, and caspase-9 genes using real-time quantitative PCR. Caspase-3 activity was also analyzed. Results showed that cell viability was significantly reduced to 42.2?±?0.01% and 19.40?±?0.01% by 5 and 8?mg?ml^?1 of L. acidophilus and L. delbrueckii extracts, respectively. Apoptosis induction was shown with both bacterial extracts. Caspase-9 and caspase-3 overexpression as well as Bax/Bcl-2 ratio increase revealed the ability of both probiotics to induce intrinsic pathway-dependent apoptosis. The extrinsic pathway was also activated by L. acidophilus. At the concentration of 198?µg?ml^?1, L. acidophilus and L. delbrueckii had a DPPH scavenging activity of 59.37?±?3.97% and 71.19?±?3.64%, respectively. Taken together, these findings provide evidence for antiproliferative, proapoptotic, and antioxidant effects driven by these probiotic lactic acid bacteria (LAB) strains.     

The influence of cheese type and fat extraction method on the content of conjugated linoleic acid

Milk and dairy products, including cheeses, are the richest sources of CLA in our diet. Determination of CLA content in these products requires extraction of fat from the sample. Solvent extraction is the most-often used method for fat extraction. As an alternative method, extraction using supercritical CO₂ (SC CO₂) could be applied. The aim of the present study was to compare the influence of solvent extraction of fat and extraction of fat with SC CO₂ on the content of conjugated linoleic acid (CLA) in ten different types of cheese. CLA content was determined by GC method after fat esterification. The type of cheese was of significance for the CLA content. The content of CLA in cheeses ranged from 0.44% to 1.31% when solvent extraction was used, and from 0.55% to 1.30% when SC CO₂ extraction was applied. The method of fat extraction had no influence on the content of CLA in 3 samples of cheese. A significantly higher content of CLA after CO₂ extraction was gained only in 1 sample of cheese, whereas in 6 samples the amount of CLA after solvent extraction was significantly higher than after extraction using SC CO₂. On the basis of the obtained results, no clear influence of the extraction method on CLA content in cheeses was found. Further investigations with the special attention on the type and properties of cheese, pressure, temperature, extraction time and volume of extracted material are needed.     

Pyrosequencing Analysis Reveals Changes in Intestinal Microbiota of Healthy Adults Who Received a Daily Dose of Immunomodulatory Probiotic Strains

The colon microbiota plays a crucial role in human gastrointestinal health. Current attempts to manipulate the colon microbiota composition are aimed at finding remedies for various diseases. We have recently described the immunomodulatory effects of three probiotic strains (Lactobacillus rhamnosus CNCM I-4036, Lactobacillus paracasei CNCM I-4034, and Bifidobacterium breve CNCM I-4035). The goal of the present study was to analyze the compositions of the fecal microbiota of healthy adults who received one of these strains using high-throughput 16S ribosomal RNA gene sequencing. Bacteroides was the most abundant genus in the groups that received L. rhamnosus CNCM I-4036 or L. paracasei CNCM I-4034. The Shannon indices were significantly increased in these two groups. Our results also revealed a significant increase in the Lactobacillus genus after the intervention with L. rhamnosus CNCM I-4036. The initially different colon microbiota became homogeneous in the subjects who received L. rhamnosus CNCM I-4036. While some orders that were initially present disappeared after the administration of L. rhamnosus CNCM I-4036, other orders, such as Sphingobacteriales, Nitrospirales, Desulfobacterales, Thiotrichales, and Synergistetes, were detected after the intervention. In summary, our results show that the intake of these three bacterial strains induced changes in the colon microbiota.     

The potential synergistic behaviour of inter- and intra-genus probiotic combinations in the pattern and rate of short chain fatty acids formation during fibre fermentation

This study compared the rate of short chain fatty acid (SCFA) production by different probiotic combinations of Lactobacillus and Bifidobacterium to determine any synergistic effects. Six different fibre fractions were fermented with nine combinations of Lactobacillus rhamnosus (LR), Lactobacillus acidophilus (LA), Bifidobacterium longum (BL) and Bifidobacterium breve (BB) for 0, 6, 24 and 48?h. SCFAs were quantified by gas chromatography. Inter-genus combinations of bacteria produced more SCFA, especially BB?+?BL?+?LR, compared to intra-genus that yielded the lowest SCFA production. Acetate was the most abundant, while propionate and butyrate were the most utilised. The SCFA formation was as acetate?>?propionate?>?butyrate and the total dietary fibre produced most of the SCFA. Most combinations utilised 60–80% of the fibre; BB?+?BL?+?LR digested the fibre completely. The quantity, pattern and the time of release of SCFA depends on the genus, but the combination of pre and probiotics is of great importance for the outcome.     

Effect of lactobacilli, bifidobacteria and inulin on the formation of aberrant crypt foci in rats

Summary Background Our studies were aimed at investigating the effect of lactic acid producing bacteria (LAB) or inulin, a natural source of non-digestible oligosaccharides derived from chicory, on the induction by carcinogens of aberrant crypt foci (ACF) in the colon, which are considered to be early precursor lesions of neoplasia. Methods Strains of Bifidobacterium longum, Lactobacillus casei and Lactobacillus acidophilus were administered to rats fed a purified high starch diet, under a variety of treatment protocols including daily gavage, via the drinking water and in the diet. The rats were treated with methyl-N-nitrosourea, 1,2-dimethylhydrazine, or azoxymethane (AOM) to induce ACF. Results In general, no consistent significant changes in ACF numbers were detected in these experiments. In one study, the basal diet of the rats was changed to one containing a higher level of fat (corn oil). Under these conditions, a significant decrease in AOM-induced colonic ACF was seen in rats given L. acidophilus or inulin. In a concurrent group of animals fed a low fat diet, no significant decrease in ACF was observed. Conclusions The results indicate that the type of diet fed can influence the detection of protective effects of LAB and oligosaccharides and that against the background of a diet with a level of fat typical of a Western diet, evidence for a protective effect of L. acidophilus and inulin towards colon cancer was obtained Received: 26 July 2001, Accepted: 26 November 2001     

Conjugated linoleic acid and human health-related outcomes

Summary There has been increasing interest in health benefits of conjugated linoleic acid (CLA) based on findings with laboratory animals. Some human studies have also suggested health benefits of CLA, but because of the mixes used these could not be readily associated with a particular isomer of CLA. A recent study examined the separate effects of near‐pure cis‐9,trans‐11 CLA (c9,t11 CLA) or trans‐10,cis‐12 CLA (t10,c12 CLA) on health‐related outcomes in healthy young males. The CLA isomers were provided in capsules and at three doses (up to about 2.5 g/day) each for 8 weeks. Both c9,t11 and t10,c12 CLA were incorporated in a dose–response fashion into blood lipids and cells. At the doses and durations used, neither isomer of CLA affected bodyweight, body mass index or body composition, insulin sensitivity, immune function or markers of inflammation. However, at the doses and durations used, c9,t11 and t10,c12 CLA had opposing effects on blood lipid concentrations. Altered dairy cow‐feeding practices were used to produce c9,t11 CLA‐rich milk and, from this ultra heat‐treated milk, cheese and butter were produced. The milk and the dairy products made from it had ninefold higher contents of c9,t11 CLA, higher contents of n‐3 fatty acids and lower contents of total fat and of saturated fatty acids. They also contained much higher contents of trans‐vaccenic acid (tVA). The modified dairy products were used in a 6‐week controlled dietary intervention study in healthy middle‐aged males. c9,t11 CLA and tVA were incorporated from dairy products into blood lipids and cells. Consumption of the CLA‐rich (and tVA‐rich) dairy products did not affect bodyweight or body mass index, insulin sensitivity or inflammatory markers. However, there were some detrimental effects on blood lipids. These effects may be due to tVA rather than to c9,t11 CLA, as they are consistent with the effects of trans fatty acids and not consistent with the effects of c9,t11 CLA identified in the earlier study with c9,t11 CLA in capsules.     

Bifidobacterium breve CNCM I-4035, Lactobacillus paracasei CNCM I-4034 and Lactobacillus rhamnosus CNCM I-4036 Modulate Macrophage Gene Expression and Ameliorate Damage Markers in the Liver of Zucker-Leprfa/fa Rats

Non-alcoholic fatty liver disease (NAFLD) has reached pandemic proportions worldwide. We have previously reported that the probiotic strains Bifidobacterium breve CNCM I-4035, Lactobacillus paracasei CNCM I-4034 and Lactobacillus rhamnosus CNCM I-4036 exert anti-inflammatory effects in the intestine of Zucker-Lepr^fa/fa rats. In this work, we focused on their hepatic effects. M1 macrophages are related to inflammation and NAFLD pathogenesis, whereas M2 macrophages release anti-inflammatory mediators. We evaluated the effects of these 3 strains on macrophage polarization, inflammation and liver damage of Zucker-Lepr^fa/fa rats. The animals received either a placebo or 10¹⁰ CFU of probiotics orally for 30 days. Nos2 and Cd86 mRNA levels were determined as markers of M1 macrophages, and Cd163 and Arg1 as M2 markers, respectively, by qRT-PCR. Liver damage was determined by lipid peroxidation, leukocyte infiltration and myeloperoxidase activity. We evaluated a panoply of circulating chemokines, the hepatic ratio P-Akt/Akt, NF-kB and P-NF-kB protein levels. All 3 probiotic strains modulated macrophage polarization in liver and circulating levels of inflammation-related mediators. L. paracasei CNCM I-4034 increased the ratio P-Akt/Akt and NF-kB protein levels. B. breve CNCM I-4035, L. paracasei CNCM I-4034 and L. rhamnosus CNCM I-4036 decreased both pro-inflammatory macrophage gene expression and leukocyte infiltration in the liver.     

Survival of Bifidobacterium longum and its effect on physicochemical properties and sensorial attributes of white brined cheese

Survival of the probiotic adjunct culture Bifidobacterium longum and cheese starters during ripening of white brined cheese, effect of the probiotic culture on physicochemical properties and sensorial attributes of cheeses were investigated throughout 90?d of ripening. Bifidobacterium longum were able to survive at higher levels (>10^7?cfu/g cheese) than the therapeutic minimum (10⁶–10^7?cfu/g cheese) after 90?d and did not have any negative effect on the survival of Streptococcus spp. (including common cheese starters). Incorporation of the probiotic adjunct into white brined cheese and high levels of their survival rates during ripening had an insignificant effect on the composition of cheeses. Results indicated that white brined cheese is a suitable food matrix for the delivery of B. longum used in this study, and white brined cheeses with B. longum may be considered as a probiotic dairy product.