Intestinal Bacteria Fluctuating in Early-Stage Colorectal Cancer Carcinogenesis are Associated with Diet in Healthy Adults.

This hospital-based, cross-sectional study aimed to explore the association between diet and fluctuating intestinal bacteria in early-stage colorectal cancer (CRC) (Atopobium parvulum, Actinomyces odontolyticus, Solobacterium moorei, and Bifidobacterium longum). Healthy participants (n = 212) who underwent total colonoscopy at National Cancer Center Hospital (Tokyo, Japan) were divided into two groups according to the relative abundance of bacteria in their feces: those in the top 25% of relative bacterial abundance as cases and the bottom 25% as controls. The participants were divided into three groups (low, medium, and high) according to their intake of food groups associated with CRC. Multivariable logistic regression analysis was conducted to estimate the association between dietary intake and higher relative abundance of bacteria. Dairy products were inversely associated with a higher relative abundance of A. parvulum, A. odontolyticus, and S. moorei, with odds ratios (high vs. low) and 95% confidence interval as follows: 0.16 (0.06-0.44), 0.25 (0.08-0.82), and 0.29 (0.11-0.78), respectively. Additionally, dietary fiber was inversely associated with a higher relative abundance of S.moorei (0.29 [0.11-0.78]). No association was observed between diet and B.longum. In conclusion, healthy adults with a higher intake of dairy products and fiber had lower odds of having a higher relative abundance of CRC-associated microbiota.

Dynamic Interplay between Microbiota Shifts and Differential Metabolites during Dairy Processing and Storage.

Due to the intricate complexity of the original microbiota, residual heat-resistant enzymes, and chemical components, identifying the essential factors that affect dairy quality using traditional methods is challenging. In this study, raw milk, pasteurized milk, and ultra-heat-treated (UHT) milk samples were collectively analyzed using metagenomic next-generation sequencing (mNGS), high-throughput liquid chromatography-mass spectrometry (LC-MS), and gas chromatography-mass spectrometry (GC-MS). The results revealed that raw milk and its corresponding heated dairy products exhibited different trends in terms of microbiota shifts and metabolite changes during storage. Via the analysis of differences in microbiota and correlation analysis of the microorganisms present in differential metabolites in refrigerated pasteurized milk, the top three differential microorganisms with increased abundance, Microbacterium (p < 0.01), unclassified Actinomycetia class (p < 0.05), and Micrococcus (p < 0.01), were detected; these were highly correlated with certain metabolites in pasteurized milk (r > 0.8). This indicated that these genera were the main proliferating microorganisms and were the primary genera involved in the metabolism of pasteurized milk during refrigeration-based storage. Microorganisms with decreased abundance were classified into two categories based on correlation analysis with certain metabolites. It was speculated that the heat-resistant enzyme system of a group of microorganisms with high correlation (r > 0.8), such as Pseudomonas and Acinetobacter, was the main factor causing milk spoilage and that the group with lower correlation (r < 0.3) had a lower impact on the storage process of pasteurized dairy products. By comparing the metabolic pathway results based on metagenomic and metabolite annotation, it was proposed that protein degradation may be associated with microbial growth, whereas lipid degradation may be linked to raw milk's initial heat-resistant enzymes. By leveraging the synergy of metagenomics and metabolomics, the interacting factors determining the quality evolution of dairy products were systematically investigated, providing a novel perspective for controlling dairy processing and storage effectively.

The role of fermentation with lactic acid bacteria in quality and health effects of plant-based dairy analogues.

The modern food industry is undergoing a rapid change with the trend of production of plant-based food products that are more sustainable and have less impact on nature. Plant-based dairy analogues have been increasingly popular due to their suitability for individuals with milk protein allergy or lactose intolerance and those preferring a plant-based diet. Nevertheless, plant-based products still have insufficient nutritional quality, undesirable structure, and earthy, green, and bean-like flavor compared to dairy products. In addition, most plant-based foods contain lesser amounts of essential nutrients, antinutrients limiting the bioavailability of some nutrients, and allergenic proteins. Novel processing technologies can be applied to have a homogeneous and stable structure. On the other hand, fermentation of plant-based matrix with lactic acid bacteria can provide a solution to most of these problems. Additional nutrients can be produced and antinutrients can be degraded by bacterial metabolism, thereby increasing nutritional value. Allergenic proteins can be hydrolyzed reducing their immunoreactivity. In addition, fermentation has been found to reduce undesired flavors and to enhance various bioactivities of plant foods. However, the main challenge in the production of fermented plant-based dairy analogues is to mimic familiar dairy-like flavors by producing the major flavor compounds other than organic acids, yielding a flavor profile similar to those of fermented dairy products. Further studies are required for the improvement of the flavor of fermented plant-based dairy analogues through the selection of special microbial cultures and formulations.

Improving the microbiological safety and quality of aquatic products using nonthermal processing.

Spoilage and deterioration of aquatic products during storage are inevitable, posing significant challenges to their suitability for consumption and the sustainability of the aquatic products supply chain. Research on the nonthermal processing of fruit juices, probiotics, dairy products, and meat has demonstrated positive outcomes in preserving quality. This review examines specific spoilage bacteria species and mechanisms for various aquatic products and discusses the principles, characteristics, and applications of six nonthermal processing methods for bacterial inhibition to maintain microbiological safety and physicochemical quality. The primary spoilage bacteria groups differ among fish, crustaceans, and shellfish based on storage conditions and durations. Four metabolic pathways utilized by spoilage microorganisms-peptides and amino acids, nitrogen compounds, nucleotides, and carbohydrates-are crucial in explaining spoilage. Nonthermal processing techniques, such as ultrahigh pressure, irradiation, magnetic/electric fields, plasma, and ultrasound, can inactivate microorganisms, thereby enhancing microbiological safety, physicochemical quality, and shelf life. Future research may integrate nonthermal processing with other technologies (e.g., modified atmosphere packaging and omics) to elucidate mechanisms of spoilage and improve the storage quality of aquatic products.

Impact of lactic acid bacteria and their metabolites on the techno-functional properties and health benefits of fermented dairy products.

After conversion of lactose to lactic acid, several biochemical changes occur such as enhanced protein digestibility, fatty acids release, and production of bioactive compounds etc. during the fermentation process that brings nutritional and quality improvement in the fermented dairy products (FDP). A diverse range of lactic acid bacteria (LAB) is being utilized for the development of FDP with specific desirable techno-functional attributes. This review contributes to the knowledge of basic pathways and changes during fermentation process and the current research on techniques used for identification and quantification of metabolites. The focus of this article is mainly on the metabolites responsible for maintaining the desired attributes and health benefits of FDP as well as their characterization from raw milk. LAB genera including Lactobacillus, Streptococcus, Leuconostoc, Pediococcus and Lactococcus are involved in the fermentation of milk and milk products. LAB species accrue these benefits and desirable properties of FDP producing the bioactive compounds and metabolites using homo-fermentative and heterofermentative pathways. Generation of metabolites vary with incubation and other processing conditions and are analyzed and quantified using highly advanced and sophisticated instrumentation including nuclear magnetic resonance, mass-spectrometry based techniques. Health benefits of FDP are mainly possible due to the biological roles of such metabolites that also cause technological improvements desired by dairy manufacturers and consumers.

Rapid detection of Listeria monocytogenes in dairy products by a novel chemilumonogenic approach.

Routine monitoring of foodborne pathogens such as Listeria monocytogenes in food processing environments are time-consuming necessities to ensure food safety. Alternative rapid diagnostic methods for pathogen detection are increasingly used, but often demand specialized equipment, making them unsuitable for on-site testing. This short communication describes the successful demonstration of combining the sample preparation method Matrix-Lysis with a chemiluminescent based detection platform (AquaSpark™) for detection of L. monocytogenes in milk and yogurt. The proposed method was evaluated against qPCR resulting in 100% relative specificity for both foodstuffs and a relative sensitivity of 100% for milk as well as 96% for yogurt for bacterial levels >1 CFU/ml. Only at very low initial bacterial concentrations (<1 CFU/ml) diverging results were found highlighting the advantages and limitations of both methods. While being less susceptible to contamination and false positive results from non-growing or dead cells, qPCR had a slightly lower overall detection limit. However, it has to be pointed out that qPCR has an increased analytical cost and also requires an additional 24 h analysis time. This study demonstrates the first successful application of a chemilumonogenic detection approach for L. monocytogenes in food that has a high potential for on-site testing.

Impact of carbon dioxide on the radial growth of fungi isolated from dairy environment.

In dairy industry, filamentous fungi are used as adjunct cultures in fermented products for their technological properties but they could also be responsible for food spoilage and mycotoxin production. The consumer demands about free-preservative products has increased in recent years and lead to develop alternative methods for food preservation. Modified Atmosphere Packaging (MAP) can inhibit fungal growth and therefore increase the food product shelf-life. This study aimed to evaluate radial growth as a function of CO2 and more particularly carbonic acid for fourteen adjuncts and/or fungal spoiler isolated from dairy products or dairy environment by using predictive mycology tools. The impact of the different chemical species linked to CO2 (notably carbonic acid) were study because it was reported previously that undissociated carbonic acid impacted bacterial growth and bicarbonates ions were involved in modifications of physiological process of fungal cells. A significant diversity in the responses of selected strains was observed. Mucor circinelloides had the fastest growth rates (µ > 11 mm. day-1) while Bisifusarium domesticum, Cladosporium herbarum and Penicillium bialowiezense had the slowest growth rates (µ < 1 mm. day-1). Independently of the medium pH, the majority of strains were sensitive to total carbonic acid. In this case, it was not possible to conclude if CO2 active form was gaseous or aqueous so modeling were performed as a function of CO2 percentage. Only Geotrichum candidum and M. circinelloides strains were sensitive to undissociated carbonic acid. Among the fourteen strains, P. bialowiezense was the less sensitive strain to CO2, no growth was observed at 50% of CO2 only for this strain. M. lanceolatus was the less sensitive strain to CO2, the CO250 which reduce the growth rates by 50% was estimated at 138% of CO2. Low CO2 percentage improved the growth of Penicillium expansum, Penicillium roqueforti and Paecilomyces niveus. Mathematical models (without and with optimum) were suggested to describe the impact of CO2 percentage or undissociated carbonic acid concentration on fungal growth rate.

Microencapsulation by a Spray Drying Approach to Produce Innovative Probiotics-Based Products Extending the Shelf-Life in Non-Refrigerated Conditions.

Recently, there has been a growing interest in producing functional foods containing encapsulated probiotic bacteria due to their positive effects on human health. According to their perceived health benefits, probiotics have been incorporated into a range of dairy products, but the current major challenge is to market new, multicomponent probiotic foods and supplements. Nevertheless, only a few products containing encapsulated probiotic cells can be found as non-refrigerated products. In this work, spray drying technology was investigated in order to produce an innovative nutraceutical formulation based on lactic acid bacteria (LAB), and was able to ensure a good storage stability of probiotics (no less than 109 CFU/cps) in non-refrigerated conditions. Probiotic-loaded microparticles from spray drying experiments were produced under different conditions and compared by thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and the enumeration of the number of viable cells in order to identify the formulation exhibiting the most promising characteristics. Results from the dissolution test revealed that the optimized formulation provides a suitable amount of living cells after digestion of microparticles stored for 12 months at room temperature and confirmed that the microencapsulation process by spray drying ensures a good protection of probiotics for nutraceutical purposes.

Disclosing Lactobacillus delbrueckii subsp. bulgaricus intraspecific diversity in exopolysaccharides production.

Exopolysaccharides production by 3 ropy strains of Lactobacillus delbrueckii subsp. bulgaricus of dairy origin was evaluated in synthetic medium by combining different approaches: impedometric measurements, fluorescent microscopy and flow cytometry analyses. The evaluation of ΔE by impedometric measurement (E%max-E%40h) allowed the detection of EPS production in synthetic medium, but the differences in EPS production kinetic was highlighted by flow cytometry analysis and fluorescent microcopy. This approach enabled us to unravel the diversity in EPS synthesis and release into the laboratory medium during the growth of the strains. Our results showed that the maximum EPS production occurred after 8 h of incubation, when cells were in late exponential growth phase. Furthermore, flow cytometry analysis revealed that only part of the cell population could be identified as EPS producer or as EPS-bounded cell. Therefore, the combined approach used, allowed us to define at the same time the kinetics of EPS production and release by three strains belonging to the same species and, highlight that the production of EPS depends also on the number of EPS-producing cells within the same population. This approach could be useful for the selection of strains to be used as starter cultures in dairy products where EPS production is considered an important feature.

Invited review: Review of taxonomic changes in dairy-related lactobacilli.

The genus Lactobacillus has represented an extremely large and diverse collection of bacteria that populate a wide range of habitats, and which may have industrial applications. Researchers have grappled with the immense genetic, metabolic, and ecological diversity within the genus Lactobacillus for many years. As a result, the taxonomy of lactobacilli has been extensively revised, incorporating new genus names for many lactobacilli based on their characteristics including genomic similarities. As a result, many lactobacilli traditionally associated with dairy products now have new genus names and are grouped into new clades or clusters of species. In this review, we examine how the taxonomic restructuring of the genus Lactobacillus will affect the dairy industry and discuss lactobacilli associated with dairy production, processing, and those that confer possible health benefits when delivered by dairy products.

Analytical strategies for the determination of biogenic amines in dairy products.

Biogenic amines (BA) are mainly produced by the decarboxylation of amino acids by enzymes from microorganisms that emerge during food fermentation or due to incorrectly applied preservation processes. The presence of these compounds in food can lead to a series of negative effects on human health. To prevent the ingestion of high amounts of BA, their concentration in certain foods needs to be controlled. Although maximum legal levels have not yet been established for dairy products, potential adverse effects have given rise to a substantial number of analytical and microbiological studies: they report concentrations ranging from a few mg/kg to several g/kg. This article provides an overview of the analytical methods for the determination of biogenic amines in dairy products, with particular focus on the most recent and/or most promising advances in this field. We not only provide a summary of analytical techniques but also list the required sample pretreatments. Since high performance liquid chromatography with derivatization is the most widely used method, we describe it in greater detail, including a comparison of derivatizing agents. Further alternative techniques for the determination of BA are likewise described. The use of biosensors for BA in dairy products is emerging, and current results are promising; this paper thus also features a section on the subject. This review can serve as a helpful guideline for choosing the best option to determine BA in dairy products, especially for beginners in the field.

Spoilage potential of Bacillus subtilis in a neutral-pH dairy dessert.

The objective of this study was the characterization of the microbiota associated with spoilage of vanilla cream pudding during storage at different temperatures. Commercial cream samples were stored aerobically at 4, 8, 12 and 15 °C for a maximum time period of 40 days. At appropriate time intervals, cream samples were subjected to: (i) microbiological analyses, and (ii) high-performance liquid chromatography (HPLC). Furthermore, the spoilage microbiota was identified through repetitive extragenic palindrome-PCR, while selected isolates were further characterized based on sequencing of the V1-V3 region of the 16S rRNA gene. Microbial growth was observed only during storage of cream samples at 12 and 15 °C, with the applied genotypic analysis demonstrating that Bacillus subtilis subsp. subtilis was the dominant spoilage microorganism of this product. Based on the HPLC analysis results, citric acid and sucrose were the most abundant organic acid and sugar, respectively throughout storage of cream pudding, whereas notable changes mainly included: (i) increase in the concentration of lactic acid and to a lesser extent of formic and acetic acids, and (ii) increase in the concentration of glucose and fructose at the expense of sucrose and lactose. The results of this study should be useful for the dairy industry in detecting and controlling microbiological spoilage in cream pudding and other chilled, neutral-pH dairy desserts.

Quantitative detection of trace VBNC Cronobacter sakazakii by immunomagnetic separation in combination with PMAxx-ddPCR in dairy products.

One immunomagnetic separation (IMS) assay based on immunomagnetic beads (IMBs) has been evaluated as a potential pretreatment tool for the separation and enrichment of target bacteria. In this study, we successfully immobilized antibodies onto magnetic bead surfaces to form IMBs through biotin and a streptavidin (SA) system to capture viable but nonculturable (VBNC) Cronobacter sakazakii (C. sakazakii) from dairy products. Various parameters that affected the capture efficiency (CE) of IMS, including the number of antibodies, IMBs dose, incubation time, magnetic separation time, and immunoreaction temperature, were systematically investigated. We further determined the optimal enrichment conditions for different dairy substrates to ensure maximum enrichment of target pathogens in the system. An IMS technique combining improved propidium monoazide (PMAxx) and droplet digital PCR (ddPCR) was established to detect the pathogenic VBNC C. sakazakii. The IMS-PMAxx-ddPCR method after IMBs enrichment showed higher accuracy when the VBNC C. sakazakii was under 1 Log10 copies/g. The detection limit for this method in a background of powdered infant formula (PIF) was 5.6 copies/g. In summary, the developed IMS-PMAxx-ddPCR method has great potential for the analysis and detection of VBNC bacteria in food.

Epidemiological trends of foodborne Campylobacter outbreaks in the United States of America, 1998-2016.

Campylobacter is a major cause of foodborne diarrheal infections in the United States of America (USA). This study aimed to elucidate the patterns of Campylobacter foodborne outbreaks temporally and spatially concerning food vehicles. We collected the data of foodborne outbreaks from 1998 to 2016 reported to the Centers for Disease Control and Prevention. The incidence rate of outbreaks for each food source was calculated and analyzed for each variable including season, food location, and census region. Overall, 465 single-state outbreaks and 8003 cases were reported during 1998-2016. Outbreaks were frequently attributed to dairy products (32%), chicken (17%) and vegetables (6%). Binomial regression analysis showed that compared to chicken items, the highest rate ratio of outbreaks was associated with dairy products (1.86) followed by vegetables (1.35) and meat products (0.76). More outbreaks were reported in the summer (35%) followed by the spring (26%) and fall (22%) season. We found that the highest number of outbreaks occurred in the West 159 (34%) and Midwest 137 (29%) census regions. The study highlights the role of dairy, chicken, and vegetables as food vehicles in Campylobacter outbreaks. Findings from this study can help in devising strategies to mitigate the increasing occurrence of Campylobacter foodborne outbreaks.

Acetate kinase and peptidases are associated with the proteolytic activity of Lactobacillus helveticus isolated from fermented food.

Lactobacillus (L.) helveticus is widely used in food industry due to its high proteolytic activity. However, such activity varies greatly between isolates, and the determining factors regulating the strength of proteolytic activity in L. helveticus are unclear. This study sequenced the genomes of 60 fermented food-originated L. helveticus and systemically examined the proteolytic activity-determining factors. Our analyses found that the strength of proteolytic activity in L. helveticus was independent of the isolation source, geographic location, phylogenetic closeness between isolates, and distribution of cell envelope proteinases (CEPs). Genome-wide association study (GWAS) identified two genes, the acetate kinase (ackA) and a hypothetical protein, and 15 single nucleotide polymorphisms (SNPs) that were associated with the strength of the proteolytic activity. Further investigating the functions of these gene components revealed that ackA and two cysteine peptidases coding genes (pepC and srtA) rather than the highly heterogeneous and intraspecific CEPs were linked to the level of proteolytic activity. Moreover, the sequence type (ST) defined by SNP analysis revealed a total of ten STs, and significantly weaker proteolytic activity was observed among isolates of ST2. This study provides practical information for future selection of L. helveticus of strong proteolytic activity.

Invited review: Controlling dairy product spoilage to reduce food loss and waste.

Food loss and waste is a major concern in the United States and globally, with dairy foods representing one of the top categories of food lost and wasted. Estimates indicate that in the United States, approximately a quarter of dairy products are lost at the production level or wasted at the retail or consumer level annually. Premature microbial spoilage of dairy products, including fluid milk, cheese, and cultured products, is a primary contributor to dairy food waste. Microbial contamination may occur at various points throughout the production and processing continuum and includes organisms such as gram-negative bacteria (e.g., Pseudomonas), gram-positive bacteria (e.g., Paenibacillus), and a wide range of fungal organisms. These organisms grow at refrigerated storage temperatures, often rapidly, and create various degradative enzymes that result in off-odors, flavors, and body defects (e.g., coagulation), rendering them inedible. Reducing premature dairy food spoilage will in turn reduce waste throughout the dairy continuum. Strategies to reduce premature spoilage include reducing raw material contamination on-farm, physically removing microbial contaminants, employing biocontrol agents to reduce outgrowth of microbial contaminants, tracking and eliminating microbial contaminants using advanced molecular microbiological techniques, and others. This review will address the primary microbial causes of premature dairy product spoilage and methods of controlling this spoilage to reduce loss and waste in dairy products.

Why knowledge is the best way to reduce the risks associated with raw milk and raw milk products.

In an age of flexible conditions about mandatory milk pasteurisation, this opinion-based research reflection supports the view that the knowledge and the awareness of milk-borne infections are key requirements to decrease the risks associated with raw milk. Providing an analysis of the current potential risks related to consumption of raw milk and raw milk products, we discuss the main reasons to continue to be vigilant about milk-borne pathogens and the current scenario in relation to the formal and clandestine sale of raw milk. Finally, we select some highly effective strategies to reduce the risks associated with raw milk in food services. Regardless of whether a country regulation allows or prohibits the trade of raw milk and its products, this is not the time to be negligent.

Prevalence and Survival of Stenotrophomonas Species in Milk and Dairy Products in Egypt.

Stenotrophomonas maltophilia is a nosocomial, multidrug-resistant pathogen that causes significant economic losses in milk production and deterioration of dairy product quality. This study investigates the prevalence and the survival of S. maltophilia under different food preservation conditions. A total of 240 samples, including farm-sourced milk, dairy shop purchased milk, Kareish cheese, Domiati cheese, ice cream, yoghurt, cooking butter, and unpasteurized cream were collected from various locations in Beni-Suef Governorate, Egypt. Thirty samples of each product were analyzed by standard biochemical tests for the presence of Stenotrophomonas spp., which was isolated from 36% (87/240) of the examined samples. The highest prevalence was observed in ice cream (80%), followed by unpasteurized cream (67%), whereas the lowest incidence was in Domiati cheese (3.3%). S. maltophilia, identified by PCR, was found only in unpasteurized cream (13%), cooking butter (10%), ice cream (6.7%), and dairy shop milk (3.3%). We also studied the viability of S. maltophilia in laboratory manufactured cream, butter, and cheese under different preservation conditions. S. maltophilia was able to survive for 30, 30, 28, 30, and 8 d in the inoculated cream, butter 0% salt, butter 3% salt, cheese 0% salt, and cheese 6% salt, respectively. Thus, S. maltophilia was able to survive more than predicted in all products in this study. This suggests that strains of S. maltophilia may develop adaptive strategies that enable survival under different food preservation conditions, which contradicts previous knowledge about the sensitivity of this microbe to environmental stress conditions. Our overall aim was to draw attention to the prevalence and future potential for increased public health significance of Stenotrophomonas spp.

Diversity of yeasts and moulds in dairy products from Umbria, central Italy.

In this research communication we report on the diversity of yeast and mould species in 69 samples of milk and different dairy products from three plants located in Umbria, central Italy. Isolates were characterised both macroscopically and microscopically and then identified by PCR and genome sequencing of the ITS region and the D1-D2 domain of the large-subunit rRNA gene for filamentous fungi and yeasts, respectively. Out of the 69 samples analysed, 51 (73.9%) tested positive for the presence of yeasts, whereas moulds were detected in 25 (36.2%) samples. A total of 9 yeast species belonging to 8 different genera and 13 mould species belonging to 6 different genera were isolated. The most common genera isolated were Debaryomyces and Kluyveromyces among the yeasts and Penicillium and Galactomyces among the moulds. Microbiota play a key role in the formation of flavour, aroma, texture and appearance of dairy products. This complex microbial ecosystem includes both cultured and external bacteria, yeasts and moulds. Some of them have an important role in the production of cheeses, whereas others are responsible for dairy product spoilage, resulting in significant food waste and economic losses. Some species can produce mycotoxins, representing a potential hazard for the consumer's safety. This study provides interesting information on the diversity of fungi species in dairy products from central Italy that can be of major importance to identify these products and to develop adequate strategies for fungal spoilage control and consumer safety.

N, O-codoped hierarchical porous graphitic carbon for electrochemical immunosensing of Lactobacillus rhamnosus GG.

An ultrasensitive label-free electrochemical immunosensor was fabricated for quantitative detection of Lactobacillus rhamnosus GG (LGG). The N/O co-doped three-dimensional hierarchical porous graphitic (THPG) carbon was synthesized by a one-step synthesis of polyaniline hydrogel, and followed by simple carbonization and chemical activation procedures. Because of the unique structure design, the obtained THPG carbon networks possess an ultra-large specific surface area of 4859 m2 g-1 along with a class of highly graphitic carbons. The results offer an enormous surface area and excellent electrical conductivity for label-free electrochemical immunosensing of probiotic L. rhamnosus strain. Under optimal conditions, the immunosensor showed a good linear relationship between peak current and concentration of LGG (R2 = 0.9976), with a detection limit of 2 CFU mL-1. Furthermore, this label-free immunosensor also shows good specificity, long-term stability, and reliability, and could be applied to detect probiotic LGG in dairy products and drinks with satisfactory results. The present protocol was shown to be quite promising for practical screening and functional evaluation of probiotic products containing LGG. A ultrasensitive label-free electrochemical immunosensor based on THPG carbon was fabricated for detection of Lactobacillus rhamnosus GG.