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BACKGROUND Cinnamoyl esterase (CE) can release antioxidant phenolic acids from its non-digestible ester-linked form. Fermentation using CE-producing lactic acid bacteria (LAB) can be useful in the food industry because of its ability to produce bioactive compounds and antibacterial metabolites. The purpose of this study was to confirm the food applicability of LAB with CE-producing ability and broad-spectrum antibacterial activity. RESULTS Among the 219 bacterial strains identified in infant feces, five Lactobacillus gasseri and six Limosilactobacillus fermentum with a high CE activity were isolated. The survival rate of all selected LABs was > 95% at pH 2.5 for 3 h and > 70% when treated with 0.3% bile salt for 4 h. Moreover, cell-free supernatants of all strains strongly inhibited five food-borne bacterial pathogens (Listeria monocytogenes, Salmonella enterica, Escherichia coli O157:H7, Bacillus cereus, and Staphylococcus aureus) and three toxin-producing fungal pathogens (Aspergillus niger, Penicillium sp., and Fusarium oxysporum). To improve phenolic acid content and rice bran preservation, Limosilactobacillus fermentum J2 with the strongest CE activity and Lactobacillus gasseri N2 with the strongest antibacterial activity were used in rice bran fermentation, respectively. FRB-J2 (fermented rice bran with Limosilactobacillus fermentum J2) and FRB-N2 (fermented rice bran with Lactobacillus gasseri N2) significantly increased caffeic acid and ferulic acid (P

The whole genome sequence of Lactiplantibacillus plantarum DJF10, isolated from Korean raw milk, is reported, along with its genomic analysis of probiotics and safety features. The genome consists of 29 contigs with a total length of 3,385,113 bp and a GC content of 44.3%. The average nucleotide identity and whole genome phylogenetic analysis showed the strain belongs to Lactiplantibacillus plantarum with 99% identity. Genome annotation using Prokka predicted a total of 3235 genes, including 3168 protein-coding sequences (CDS), 59 tRNAs, 7 rRNAs and 1 tmRNA. The functional annotation results by EggNOG and KEGG showed a high number of genes associated with genetic information and processing, transport and metabolism, suggesting the strain’s ability to adapt to several environments. Various genes conferring probiotic characteristics, including genes related to stress adaptation to the gastrointestinal tract, biosynthesis of vitamins, cell adhesion and production of bacteriocins, were identified. The CAZyme analysis detected 98 genes distributed under five CAZymes classes. In addition, several genes encoding carbohydrate transport and metabolism were identified. The genome also revealed the presence of insertion sequences, genomic islands, phage regions, CRISPR-cas regions, and the absence of virulence and toxin genes. However, the presence of hemolysin and antibiotic-resistance-related genes detected in the KEGG search needs further experimental validation to confirm the safety of the strain. The presence of two bacteriocin clusters, sactipeptide and plantaricin J, as detected by the BAGEL 4 webserver, confer the higher antimicrobial potential of DJF10. Altogether, the analyses in this study performed highlight this strain's functional characteristics. However, further in vitro and in vivo studies are required on the safety assurance and potential application of L. plantarum DJF10 as a probiotic agent.

According to health functional food law in Korea, red ginseng is classified as a health functional ingredient. In order to establish the optimal manufacturing condition of red ginseng string cheese, red ginseng powder was added to string cheese in different manufacturing processes which are raw milk before pasteurization (T1), curd before stretching (T2), and hot water for stretching curd (T3), respectively. After 2 weeks of storage period, the hardness of control cheese was lowest and decreased, as compared to 0 week, while the hardness of all string cheese with red ginseng powder was maintained (p

Lactic acid bacteria (LAB) play an important role in dairy fermentations, notably as cheese starter cultures. During the cheese production and ripening period, various enzymes from milk, rennet, starter cultures, and non-starter LABs are involved in flavor formation pathways, including glycolysis, proteolysis, and lipolysis. Among these three pathways, starter LABs are particularly related to amino acid degradation, presumably as the origins of major flavor compounds. Therefore, we used several enzymes as major criteria for the selection of starter bacteria with flavor-forming ability. Lactococcus lactis subsp. lactis LDTM6802 and Lactococcus lactis subsp. cremoris LDTM6803, isolated from Korean raw milk and cucumber kimchi, were confirmed by using multiplex PCR and characterized as starter bacteria. The combinations of starter bacteria were validated in a miniature Gouda-type cheese model. The flavor compounds of the tested miniature cheeses were analyzed and profiled by using an electronic nose. Compared to commercial industrial cheese starters, selected starter bacteria showed lower pH, and more variety in their flavor profile. These results demonstrated that LDTM6802 and LDTM6803 as starter bacteria have potent starter properties with a characteristic flavor-forming ability in cheese.

The protective effect of pig skin gelatin water extracts (PSW) and the low molecular weight hydrolysates of PSW generated via enzymatic hydrolysis with Flavourzyme® 1000L (LPSW) against scopolamine-induced impairment of cognitive function in mice was determined. Seventy male ICR mice weighing 20–25 g were randomly assigned to seven groups: Control (CON); scopolamine (SCO, 1 mg/kg B.W., intraperitoneally (i.p.); tetrahydroaminoacridine 10 [THA 10, tacrine; 10 mg/kg B.W. per oral (p.o.) with SCO (i.p.)]; PSW 10 (10 mg/kg B.W. (p.o.) with SCO (i.p.); PSW 40 (40 mg/kg B.W. (p.o.) with SCO (i.p.); LPSW 100 (100 mg/kg B.W. (p.o.) with SCO (i.p.); LPSW 400 (400 mg/kg B.W. (p.o.) with SCO (i.p.). All treatment groups, except CON, received scopolamine on the day of the experiment. The oxygen radical absorbance capacity of LPSW 400 at 1 mg/mL was 154.14 μM Trolox equivalent. Administration of PSW and LPSW for 15 weeks did not significantly affect on physical performance of mice. LPSW 400 significantly increased spontaneous alternation, reaching the level observed for THA and CON. The latency time of animals receiving LPSW 400 was higher than that of mice treated with SCO alone in the passive avoidance test, whereas it was shorter in the water maze test. LPSW 400 increased acetylcholine (ACh) content and decreased ACh esterase activity (p

Gouda cheese, one of most popular cheeses in the Korea, has been produced from only pasteurized milk in Korean dairy farms. Recently, it has become legally possible to produce ripened cheese manufactured with raw milk in Korea. In the present study, we investigated the physico-chemical and microbiological characteristics of Gouda cheese manufactured with raw (R-GC) or pasteurized milk (P-GC) during manufacturing and ripening. Particularly, this study characterized the bacterial community structure of two cheese types, which are produced without pasteurization during ripening based on next generation sequencing of 16S rRNA gene amplicons. During ripening, protein and fat content increased slightly, whereas moisture content decreased in both P-GC and R-GC. At the 6 wk of ripening, R-GC became softer and smoother and hence, the values of hardness and gumminess, chewiness in R-GC was lower than that of P-GC. Metagenomic analysis revealed that the bacterial genera used a starter cultures, namely Lactococcus and Leuconostoc were predominant in both P-GC and R-GC. Moreover, in R-GC, the proportion of coliform bacteria such as Escherichia, Leclercia, Raoultella, and Pseudomonas were detected initially but not during ripening. Taken together, our finding indicates the potential of manufacturing with Gouda cheese from raw milk and the benefits of next generation sequencing for microbial community composition during cheese ripening.

Geographical origin and authenticity are the two crucial factors that propel overall cheese perception in terms of quality and price; therefore, they are of great importance to consumers and commercial cheese producers. Herein, we demonstrate a rapid, accurate method for discrimination of domestic and import mozzarella cheeses in the Republic of Korea by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). The protein profiles’ data aided by multivariate statistical analysis successfully differentiated farmstead and import mozzarella cheeses according to their geographical location of origin. A similar investigation within domestic samples (farmsteads/companies) also showed clear discrimination regarding the producer. Using the biomarker discovery tool, we identified seven distinct proteins, of which two (m/z 7407.8 and 11,416.6) were specific in farmstead cheeses, acting as potential markers to ensure authentication and traceability. The outcome of this study can be a good resource in building a database for Korean domestic cheeses. This study also emphasizes the combined utility of MALDI-TOF MS and multivariate analysis in preventing fraudulent practices, thereby ensuring market protection for Korean farmstead cheeses.

To evaluate the safety and risk assessment of cheese consumption in the Republic of Korea, sixty cheese samples purchased from the farmstead and retails markets (imported) were analyzed for their biogenic amine (BA) contents. The BA profiles and quantities of eight amines (tryptamine, 2-phenylethylamine, putrescine, cadaverine, histamine, tyramine, spermidine, and spermine) were determined using high-performance liquid chromatography (HPLC). Spermine was the only amine detectable in all the samples. The BAs of fresh cheeses from both farmstead and retail markets were mostly undetectable, and comparatively at lower levels (1000 mg/kg, of which histamine accounts nearly 86 and 77% of the total levels, respectively. The tolerable limits of the potential toxic amines, histamine and tyramine surpassed in four and three imported ripened samples, respectively. Furthermore, the presence of potentiators (putrescine and cadaverine) together in samples even with a lower level of toxic amines alarms the risk in consumption. Therefore, adoption of strict hygienic practices during the entire chain of cheese production, along with obligatory monitoring and regulation of BA in cheeses seems to be mandatory to ensure the safety of the consumers.

Background: The OppA receptor as a ATP-binding cassette (ABC) transporter plays key roles in protecting host organism and transport nutrients across the intestine by the oligopeptide transporter from symbiotic bacteria directs maturation of the host immune system. Among lactic acid bacteria, Bifidobacterium longum KACC91563, isolated from fecal samples of healthy Korean neonates, has the capability to alleviate food allergy effects. The extracellular OppA receptor from gram-positive Bifidobacterium longum KACC91563 translocate nutrients-peptides from the outside environment of intestinal tract to the inside of the symbiotic cell, as a peptide importer. Hence, it was attempting to explicate the relationship between the substrate’s specificity from the OppA importer and the probiotic effects of B. logum KACC91563 in the host intestine. The probiotic effects of B. logum KACC91563 were attributed to the enhancement of the epithelial barrier by several different strain sepcific ways to prevent the strong adhesion of pathogens. The specialized structure-function relationship from the OppA importer could provide the abstract of substrate specificity into unique immunological properties of that the host organism.Results: In the study, we characterized the extracellular OppA importer from B. longum KACC91563 of intestinal microbiome by various protein structure-based modelings in silico. Structural characterization by conserved 5 patches and 4 functional motifs from specific trace residues of the OppA importer. The hydrate surface of the binding site had been decipted by specific trace residues of the OppA that trace residues of Thr58, Lys185, Trp443, and Tyr447, which were characterized in highly exposed hydrophobic binding pocket by its aggregation prones. Therefore, the spatial aggregation propensity in the binding site of the extracellular OppA importer plays a vital role in the specific interaction determinant for peptide binding. In addition, alanine mutation energy values allowed for the virtual determination of the relationships between the energy effects of the peptide binding site mutation on the transporter structural stability, the peptide binding affinity, and the transporter-related peptide substrate selectivity from OppA importer. In particular, distinctive seven pharmacophoric features comprised of two H-bonding donor(P1), three H-bonding acceptor(P8), and two hydrophobic points (P5 and P8) matched the the OppA receptor-peptide ligand interactions within their binding pocket structure. There are distinct interactions to fix the positions of the N(P1) and C(P8) termini of the complex of OppA-peptide from B. longum KACC91563 such as side chain-specific interactions with the OppA, compared to that of the Lactococcus latis (L. lactics) OppA.Conclusions: The specialized structure-function relationship from the OppA import could provide the abstract of substrate specificity into unique immunological properties of the host organism by stucutre-based molecular modeling. In the current study, we attempted explication of the relationship between the substrate’s specificity from the OppA importer and the probiotic effects of B. longum KACC91563 in the host intestine based on the structure-function perspectives of the OppA importer. Moreover, functional characterization of solute-binding proteins (such as 15 cell wall proteins and 20 extracellular proteins) on the B. longum KACC91563 genome will lead to insight of key switch for substate’s metabolism into reprogramming immune responses in the host intestine.

Intake of probiotic cheese improves the intestinal health of humans and animals. However, metabolic changes in the intestines of dogs in response to the ingestion of probiotic cheese have not been evaluated. Thus, we aimed to determine the metabolic changes in healthy beagle dogs fed queso blanco cheese with added Lactobacillus reuteri KACC 92293 and Bifidobacterium longum KACC 91563 (QCLB) and to identify potential fecal biomarkers to distinguish the metabolic changes based on intake of probiotic cheese through metabolomics approaches. The dogs were randomly divided into three groups and fed a regular diet without any cheese (control), a diet with queso blanco cheese (QC), or one with QCLB for eight weeks. The concentrations of acetic, propionic, and 4-aminobutyric acids were increased in the QCLB group compared to those in the control group. Additionally, higher levels of propionic acid and lower levels of xylose were found in the QCLB group compared to those in the QC group. This is the first report on the identification of metabolic changes in beagle dogs fed queso blanco cheese with added L. reuteri KACC 92293 and B. longum KACC 91563. We also found that metabolomics approaches can be useful for identifying potential fecal markers in dogs fed probiotic cheese.

Lactic acid bacteria (LAB) play an important role in dairy fermentations, notably as cheese starter cultures. During the cheese production and ripening period, various enzymes from milk, rennet, starter cultures, and non-starter LABs are involved in flavor formation pathways, including glycolysis, proteolysis, and lipolysis. Among these three pathways, starter LABs are particularly related to amino acid degradation, presumably as the origins of major flavor compounds. Therefore, we used several enzymes as major criteria for the selection of starter bacteria with flavor-forming ability.

The study describes the effects of administration of Queso Blanco cheese containing Bifidobacterium longum on the fecal microbiota, metabolite and serum cytokine in healthy beagle dogs. Twelve healthy beagle dogs were randomly divided in three groups of four dogs each:a control group, not fed with any cheese, and groups fed with Queso Blanco cheese with B. longum KACC 91563 (QCB) or without B. longum (QC) for 8 weeks. Fecal microbiota was analyzed using a culture-based method and 16s rRNA gene sequencing. Serum cytokine levels, activation of natural killer cells, and proliferation of peripheral blood mononuclear cells were determined. SPME-GC-MS method was used to determine the concentrations of short chain fatty acids and indole in dog feces. Administration of QCB for 4 weeks significantly increased the Bifidobacterium. QCB supplementation for 8 weeks reduceds Enterobacteriaceae and Clostridium perfringens (p 0.05). The abundance of Fusobacterium, Blautia and Collinesella in QCB group were reduced as compared with the control group. Serum TNF-α and IL-6 levels at 8 weeks significantly increased in QCB group as compared with QC group. There was no change in the concentrations of total short chain fatty acids by B. longum at 0 and 4 weeks. At week 8, the acetic acid, propionic acid and butyric acid of the QCB and QC groups were significantly decreased compared to the control group. In conclusion, our results demonstrate that administration of QCB had positive effects on fecal microbiota and immune response in beagle dogs. We suggest that Queso Blanco cheese containing B. longum KACC 91563 could be used as a functional food for companion animals.

The effects of Queso Blanco cheese containing Bifidobacterium longum KACC 91563 was studied on the intestinal microbiota and short chain fatty acids (SCFAs) in healthy companion dogs. There were three experimental groups with five healthy dogs each: a control group, not fed with any cheese, and groups fed with Queso Blanco cheese with (QCB) or without B. longum KACC 91563 (QC) for 8 weeks. Fecal samples were collected 5 times before, during, and after feeding with cheese. Intestinal microbiota was analyzed using two non-selective agar plates (BL and TS) and five selective agar plates (BS, NN, LBS, TATAC, and MacConkey). SPME-GC-MS method was applied to confirm SCFAs and indole in dog feces. The six intestinal metabolites such as acetic, propionic, butyric, valeric, isovaleric acid and indole were identified in dog feces. Administration of B. longum KACC 91563 (QCB) for 8 weeks significantly increased the beneficial intestinal bacteria such as Bifidobacterium (8.4±0.55) and reduced harmful bacteria such as Enterobacteriaceae and Clostridium (p

The present study aimed at evaluating the utilization possibility of encapsulated probiotic Bifidobacterium longum for production of functional fermented sausages. The B. longum isolated from the feces samples of healthy Korean infants encapsulated with glycerol as a cryprotectant was used for fermented sausages production as a functional bacterial ingredient, and its effect was also compared with those inoculated with commercial starter culture (CSC). Results showed that most inoculated encapsulated B. longum (initial count, 5.88 Log CFU/g) could survive after 4 days fermentation (5.40 Log CFU/g), and approximately a half (2.83 Log CFU/g) of them survived in the products after 22 days of ripening. The products inoculated with encapsulated B. longum presented the lowest lipid oxidation level, while had higher total unsaturated fatty acid content and more desirable n-6/n-3 fatty acids than those inoculated with CSC or non-inoculated control. Moreover, the odor and taste scores in the samples made with B. longum were comparable to those in the treatment with CSC. The inoculation with the B. longum had no effects on the biogenic amine contents as well as did not cause defects in color or texture of the final products. Thus, the encapsulation could preserve the probiotic B. longum in the meat mixture, and the encapsulated B. longum could be used as a functional ingredient for production of healthier fermented meat products.

Lactic acid bacteria were screened for potential probiotics for use as feed additives. We obtained 3,000 isolates from feces of: cattle, dogs, goats, and infants; milk; yogurt; cheese; fermented sausages; Kimchi; and Cheonggukjang and tested their antibacterial activity toward indicator pathogens, including Bacillus cereus, Listeria monocytogenes, Escherichia coli O157:H7, and Salmonella enterica Enteritidis. We further tested their tolerance to artificial gastric juice (1% [w/v] pepsin, pH 2.5) and bile acid (0.1% [w/v] oxgall, pH 6.8). Six isolates exhibited strong antibacterial activity against indicator pathogens. The PA40 isolate from Kimchi exhibited marked resistance to artificial gastric juice and bile acid. The antibacterial substances produced by PA40 were stable to heat, pH, and enzymes. Strain PA40 was identified as a Lactobacillus curvatus strain using chemical tests and 16S rDNA sequencing and produced 248.4 mmol/L lactic acid after 48 hr of fermentative growth. The L. curvatus PA40 strain was also highly tolerant of the artificial gastrointestinal model system. Our results indicate that L. curvatus PA40 could be used as a potential probiotic feed additive.

The recent surge in environmental awareness and consumer demand for stable, healthy, and safe foods has led the packaging and food sectors to focus on developing edible packaging materials to reduce waste. Edible films and coatings as a modern sustainable packaging solution offer significant potential to serve as a functional barrier between the food and environment ensuring food safety and quality. Whey protein is one of the most promising edible biopolymers in the food packaging industry that has recently gained much attention for its abundant nature, safety, and biodegradability and as an ecofriendly alternative of synthetic polymers. Whey protein isolate and whey protein concentrate are the two major forms of whey protein involved in the formation of edible films and coatings. An edible whey film is a dry, highly interacting polymer network with a three-dimensional gel-type structure. Films/coatings made from whey proteins are colorless, odorless, flexible, and transparent with outstanding mechanical and barrier properties compared with polysaccharide and other-protein polymers. They have high water vapor permeability, low tensile strength, and excellent oxygen permeability compared with other protein films. Whey protein-based films/coatings have been successfully demonstrated in certain foods as vehicles of active ingredients (antimicrobials, antioxidants, probiotics, etc.), without considerably altering the desired properties of packaging films that adds value for subsequent industrial applications. This review provides an overview of the recent advances on the formation and processing technologies of whey protein-based edible films/coatings, the incorporation of additives/active ingredients for improvement, their technological properties, and potential applications in food packaging.

The effect of addition of the probiotic Bifidobacterium longum KACC 91563 on the chemical and sensory properties of Kwark cheese produced using CHN-11 as a cheese starter were investigated. The addition of B. longum KACC 91563 to Kwark cheese did not change the composition or pH value of the cheese, compared with control. B. longum KACC 91563 survived at a level of 7.58 Log CFU/g and did not have any negative effect on survival of the cheese starter. A sensory panel commented that the addition of B. longum KACC 91563 made Kwark cheese more desirable to consumers, and that the probiotic supplementation had no effect on perceived taste. Thus, B. longum KACC 91563 can be used for inclusion of probiotic bacteria in cheese.

Two different solvents (water and ethanol/water at 50/50 ratio) were used for extraction of phenolic contents in shiitake by-products, and the antioxidant and antimicrobial efficacies of fermented sausages incorporated with these two extracts were investigated during storage. Also, shelf-life stability of fermented sausages fortified with these two extracts was compared with those fortified with BHT (0.02%) or nitrite (0.01%)/nitrate (0.005%). Significantly higher antioxidant activities (e.g., ferrous ion chelating and DPPH scavenging) and inhibitory capacity against lipid oxidation (e.g., TBARS reduction) were observed in the fermented sausages made with ethanolic extract (shiitake by-products extracted with ethanol/water) compared with those added with aqueous extract (extracted with water) or BHT, nitrite/nitrate and control throughout storage. The ethanolic extract treated-samples also showed a significantly slower increasing rate of total aerobic count (6.54–6.95 log10 cfu/g) than the ones treated with aqueous extract (6.74–7.16 log10 cfu/g) during storage. Otherwise, extract obtained from the ethanolic extract treated-samples had stronger antimicrobial activities against pathogens than the one obtained from aqueous extract treated-samples (e.g., minimum inhibitory concentrations, MIC = 2.05 & 3.64, 3.12 & 5.20 and 7.29 & 10.41 mg/mL for S. aureus, L. monocytogenes and E. coli O157, respectively). Especially, the antimicrobial activity against S. typhimurium (MIC = 37.50 mg/mL) was observed only in the extract of ethanolic extract treated-samples. Our study demonstrates that the extraction with ethanol/water solvent is a more effective method to obtain bioactive compounds enriched-extract which better improved the shelf-life stability of fermented sausages during storage without defects in quality in comparison to the extraction method with water.

Summary This study aimed at assessing the utilisation possibility of Enterococcus faecalis as starter cultures for production of fermented sausages. The E. faecalis isolates isolated from faeces samples of 5-day-old healthy newborn babies, identified by 16SrDNA sequencing and free from virulence determinants as proven by genomic sequencing, were used for fermented sausages production as starter culture. Six treatments (four inoculated with four different E. faecalis isolates, one with commercial starter culture and one control) were prepared. The inoculation with E. faecalis showed a stronger acidification compared with the control. The treatments with E. faecalis showed significantly higher flavour and acceptability scores in comparison with the control or commercial starter culture. Both of commercial starter culture and E. faecalis were positive with tyramine. Apart from the amine production, the inoculation with E. faecalis generally improved the acidifying activity and flavour of the products, suggesting their application potentials in fermented sausages production as starter cultures.

Objective: This study was conducted to determine the composition and diversity of the fungal flora at various control points in cheese ripening rooms of 10 dairy farms from six different provinces in the Republic of Korea.Methods: Floor, wall, cheese board, room air, cheese rind and core were sampled from cheese ripening rooms of ten different dairy farms. The molds were enumerated using YM petrifilm, while isolation was done on yeast extract glucose chloramphenicol agar plates. Morphologically distinct isolates were identified using sequencing of internal transcribed spacer region.Results: The fungal counts in 8 out of 10 dairy farms were out of acceptable range, as per hazard analysis critical control point regulation. A total of 986 fungal isolates identified and assigned to the phyla Ascomycota (14 genera) and Basidiomycota (3 genera). Of these Penicillium, Aspergillus, and Cladosporium were the most diverse and predominant. The cheese ripening rooms was overrepresented in 9 farms by Penicillium (76%), while Aspergillusin a single farm. Among 39 species, the prominent members were Penicillium commune, P. oxalicum, P. echinulatum, and Aspergillus versicolor. Most of the mold species detected on surfaces were the same found in the indoor air of cheese ripening rooms.Conclusion: The environment of cheese ripening rooms persuades a favourable niche for mold growth. The fungal diversity in the dairy farms were greatly influenced by several factors (exterior atmosphere, working personnel etc.,) and their proportion varied from one to another. Proper management of hygienic and production practices and air filtration system would be effective to eradicate contamination in cheese processing industries.