Commercial Starter Cultures Research Articles

Lactobacilli as additional cultures in cheese making

Production of cheeses from thermally processed milk at an industrial scale is impossible without using commercial bacterial starter cultures that include a limited number of species and strains of microorganisms. This leads to the fact that sensory indicators of mass-produced cheeses practically do not differ. Traditional cheeses from unpasteurized milk are distinguished by more pronounced and diverse tastes. Scientific literature describes the significant taxonomic variety of microbiota of traditional cheeses, including non-starter lactobacilli. Sensory indicators and safety of cheeses directly depend on the composition of this microbiota. This study examines the main moments of the taxonomic reform of lactobacilli, which resulted in union of two families Lactobacillaceae and Leuconostocaceae, and division of the genus Lactobacillus into 25 genera. New description of the family and several species of lactobacilli used in starter cultures is given. The authors demonstrate the complex autochthonous microbiota of cheeses and a possibility of stabilization of fermentation upon cheese making from raw milk and improvement of their quality without losing individuality due to the introduction of selected autochthonous additional cultures. When cheeses are made from pasteurized milk, these cultures improve sensory characteristics of a product and impart the original flavor to them. Several studies show that probiotic bacteria intensively develop and maintain viability for a long time even in long-ripened cheeses. Such cheeses can be carriers of live probiotics and their metabolites that are beneficial for the consumer health. This review summarizes information about promising directions of extension of the species spectrum of additional cultures for creation of domestic starter cultures for cheese making. Taking into consideration that microbiology of cheese making is quite a wide field that is not fully studied, the review does not claim to be the comprehensive analysis of all existing approaches.

THE IMPACT OF STARTER CULTURES ON QUARK TYPE CHEESE PRODUCTION

This study was conducted to investigate the effect of starter cultures on the physicochemical and microbiological properties, texture, yield, and consumer preferences of quark type cheese. For this purpose, three different quark cheeses were manufactured by using commercial starter cultures. The microbiological, physicochemical, textural, and sensory properties of the cheese samples were determined at 1st, 14th, and 28th days of the storage period. The results showed that the kind of starter culture used in production influences the composition and yield of the obtained quark cheeses. It has been determined that the use of kefir culture in quark cheese production influences the moisture and water holding capacity, and as a result, improves its spreadability. Also, the sensory analysis exhibited that cheese produced with kefir culture had higher texture and taste-flavor acceptability. The study indicates that kefir culture may be successfully used in quark cheese production.

Use of Indigenous Lactic Acid Bacteria for Industrial Fermented Sausage Production: Microbiological, Chemico-Physical and Sensory Features and Biogenic Amine Content

The use of starter cultures in the meat industry is common, even if the number of available commercial cultures is limited, inducing product standardisation and microbial diversity reduction. On the other hand, some artisanal products relying on spontaneous fermentation can represent a source of isolation of new interesting strains. In this work, four LAB strains derived from Mediterranean spontaneously fermented sausages were tested as new starter cultures for the industrial production of fermented sausages, in comparison to a commercial starter culture. The products obtained were analysed for physico-chemical parameters, microbiota, biogenic amines and aroma profile. A consumer test was also performed to evaluate product acceptability. The strains induced different acidification kinetics. LAB counts showed high persistence when Latilactobacillus curvatus HNS55 was used as the starter culture, while the addition of Companilactobacillus alimentarius CB22 resulted in a high concentration of enterococci (6 log CFU/g), 2 log higher than in other samples. Tyramine was detected at concentrations of 150–200 mg/kg, except for in the sample produced with Lactiplantibacillus plantarum BPF2 (60 mg/kg). Differences were observed in the aroma profile, with a high amount of 2-butanone found in the samples obtained with Comp. alimentarius CB22. These latter sausages also showed the lowest score in terms of acceptability. This study allowed us to select new LAB strains for fermented sausage starter cultures, increasing the product diversification.

Identification, Safety Assessment, and Antimicrobial Characteristics of Cocci Lactic Acid Bacteria Isolated from Traditional Egyptian Dairy Products.

The main objective of this study is to isolate and identify lactic acid bacteria (LAB) from various Egyptian dairy products, examine their antibacterial and hemolysis potential, and ensure their safety when used as starter cultures in different dairy industries. Egyptian dairy products are often made without the use of commercial starter cultures, using raw milk and artisanal methods. The most popular traditional dairy products are Laban Rayeb and Zabady, as well as the cheese varieties of Ras, Domiati, and Karish. The microbial communities used for fermentation and the diversity of lactic acid bacteria are the most important factors that can affect the quality of these products. In order to investigate the diversity of cocci lactic acid bacteria in Egyptian dairy products, 70 samples of raw or fermented milk and cheeses were collected from traditional cheese-making factories, local markets, and farmhouses located in the Delta area of Egypt. Following this, the LAB were isolated from the samples. One hundred fifty-seven isolates of Gram-positive, catalase-negative, and cocci bacterial species were identified via rep-PCR, and some isolates were confirmed using pheS and 16S rRNA gene sequencing, as follows: Streptococcus infantarius subsp. infantarius (three isolates), Enterococcus hirae (three isolates), Enterococcus faecium (ninety-six isolates), Enterococcus faecalis (forty isolates), Enterococcus durans (six isolates), Lactococcus garvieae (one isolate), Pediococcus acidilactici (seven isolates), and Lactococcus lactis subsp. Lactis (one isolate). These findings validate that five strains have strong antibacterial activity against Escherichia coli, Salmonella typhimurium, and Listeria monocytogenes, and one hundred thirty-four strains were safe for hemolysis. The five strains were selected as protective cultures, including Pediococcus acidilactici, Lactococcus lactis subsp. lactis, E. faecalis, and E. faecium.

Sucuk, Turkish-Style Fermented Sausage: Evaluation of the Effect of Bioprotective Starter Cultures on Its Microbiological, Physicochemical, and Chemical Properties

Bio-protection is one of the most popular natural protection methods to control food safety and shelf life. Lactic acid bacteria, especially Lactobacilli strains, are used in the food industry for this purpose due to their probiotic properties and, accordingly, bioprotective properties. We aimed to investigate the role of the bacteriocin-producing lactic acid bacteria Lactobacillus sakei and Pediococcus acidilactici in inducing microbiological, physicochemical, and chemical changes in the Turkish-style fermented sausage sucuk. The effects of protective cultures were compared with those of commercial starter cultures consisting of Pediococcus pentosaceus + Staphylococcus carnosus; a non-cultured group was used as a control. L. sakei inoculation and, to a lower extent, P. acidilactici inoculation resulted in the rapid domination of lactic acid bacteria (LAB) in the environment, whereas commercially used starter cultures and the non-cultured group showed lower counts of LAB. Moreover, L. sakei and P. acidilactici succeeded in inhibiting pathogens including S. aureus, E. coli, and Enterobacteriaceae. The number of enterococci decreased notably in the L. sakei-inoculated sucuk samples; however, an increase was determined in the samples inoculated with P. acidilactici. On the other side, the effect of commercial starter cultures was not sufficient for the inhibition of food-borne pathogens in the sucuk samples. Consequently, the inoculation of protective cultures, particularly of L. sakei, can provide a considerable contribution to improving microbial quality and food safety, retarding lipid oxidation, and increasing proteolytic activities in sucuk without important changes in its sensory properties.

Impact of Sourdough from a Commercial Starter Culture on Quality Characteristics and Shelf Life of Gluten-Free Rice Breads Supplemented with Chickpea Flour.

This study aimed to develop a novel gluten-free bread using a rice/chickpea flour-based sourdough, fermented by a commercial starter culture, to improve the quality characteristics and shelf life of this product. The effects of sourdough incorporation, chickpea flour content (6.5 and 10.0%), and added water level (80-110%) on batter rheology and bread quality were investigated; bread textural characteristics upon storage (0-2 days) were also monitored. The level of added water was the primary factor influencing batter rheology, as evaluated by the back extrusion test. Sourdough incorporation decreased the pH and increased the acidity of batters and breads. The inclusion of sourdough, the water level, and the storage time affected the moisture and texture parameters of the bread crumb. Sourdough incorporation into bread formulations decreased crumb hardness and staling rate and increased loaf specific volume. Moreover, intermediate water (90 and 100%) and high chickpea (10%) levels in the batters increased loaf specific volumes and crust redness, respectively. Sensory analysis revealed that sourdough-enriched breads were preferred by the assessors concerning general appearance and crumb texture. Overall, bread formulations with the incorporation of sourdough, at a 90% level of added water in the batter mixtures, exhibited the most desirable characteristics according to both instrumental and sensory analyses.

Behavior of Salmonella During Preparation of a Fermented Cashew Cheese Analog

Between 2013 and 2021, there were three reported salmonellosis outbreaks in North America linked to the consumption of cashew cheese analogs that were prepared from soaked and fermented cashews. The behavior of Salmonella was evaluated during fermentation of cashews to better understand the risks associated with plant-based fermentations. Single or seven-strain rifampin-resistant Salmonella-inoculated cashews (1–2 log CFU/g) were soaked 1:1 (w/v) in sterile ultrapure water at 4 °C for 24 ± 1 h, drained, and then blended with additional water. Salmonella-inoculated or uninoculated cashews with or without added commercial Lactococcus lactis starter culture (LAB), and with LAB and NaCl (0.8% and 1.6% w/w), citric acid (0.4% w/w), or a combination of NaCl and citric acid, were held at 24 ± 1 °C for up to 72 h. The pH, aerobic plate counts (M17 agar), and Salmonella populations (CHROMagar Salmonella with 50 µg/mL of rifampin) were measured at 0, 24, 48, and 72 h in replicate experiments. When LAB was present, aerobic plate counts increased from ∼8 log CFU/g to ∼9 log CFU/g after 24 h. The pH decreased from an initial pH ∼6 to pH 4.5–5.0 at 24 h in the presence of LAB or at 48 h in the absence of LAB. The presence of LAB significantly (P < 0.0001) impacted populations of Salmonella during the fermentation. There was no significant difference in Salmonella populations between the treatments with LAB alone and the treatments with LAB in combination with added NaCl (P = 0.3484) or citric acid (P = 0.8630). After 24 h, populations of Salmonella increased by 5.3–5.5 log in the absence of LAB and by 0.5–1.7 log in the presence of LAB, with or without added NaCl. These data demonstrate the need to consider a range of control measures for safe preparation of plant-based fermented products.

Probiotic Bifidobacterium animalis ssp. lactis Probio-M8 improves the fermentation and probiotic properties of fermented milk

Probiotics are increasingly used as starter cultures to produce fermented dairy products; however, few studies have investigated the role of probiotics in milk fermentation metabolism. The current study aimed to investigate whether adding Bifidobacterium animalis ssp. lactis Probio-M8 (Probio-M8) as a starter culture strain could improve milk fermentation by comparing the physicochemical characteristics and metabolomes of fermented milks produced by a commercial starter culture with and without Probio-M8. Our results showed that adding Probio-M8 shortened the milk fermentation time and improved the fermented milk texture and stability. Metabolomics analyses revealed that adding Probio-M8 affected mostly organic acid, AA, and fatty acid metabolism in milk fermentation. Targeted quantitative analyses revealed significant increases in various metabolites related to the sensory quality, nutritive value, and health benefits of the probiotic fermented milk, including 5 organic acids (acetic acid, lactic acid, citric acid, succinic acid, and tartaric acid), 5 EAA (valine, arginine, leucine, isoleucine, and lysine), glutamic acid, and 2 essential fatty acids (α-linolenic acid and docosahexaenoic acid). Thus, applying probiotics in milk fermentation is desirable. This study has generated useful information for developing novel functional dairy products.

The Ability of Lacticaseibacillus paracasei MSMC 36-9 Strain with Probiotic Potential to Ferment Coconut Milk and Produce a Yogurt-Type Beverage

The efficacy of the Lacticaseibacillus paracasei MSMC 36-9 strain with probiotic potential to ferment coconut milk and produce coconut milk yogurt-type beverages was examined. Tapioca starch was used as a stabilizer at concentrations of 0, 1.0, and 2.0% (w/w). The samples were stored at 4 °C for 21 days and analyzed for viability and resistance to in vitro gastrointestinal conditions of L. paracasei MSMC 36-9, pH changes, radical scavenging activity using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay, and apparent viscosity. The viability of the strain with probiotic potential in the samples remained stable during storage and ranged between 12 and 13 log CFU/g by the end of the storage period. The strain L. paracasei MSMC 36-9 from all samples survived under simulated gastrointestinal conditions. The pH levels of all samples decreased during storage due to post-acidification. The radical scavenging activity of the products fermented with L. paracasei MSMC 36-9 was higher than that of the sample fermented with the commercial yogurt starter culture. The addition of tapioca starch to fermented coconut milk increased the viscosity of the samples. The results suggested that L. paracasei MSMC 36-9 can be used as a starter culture in the production of coconut milk yogurt-type beverages with antioxidant potential.

Database selection for shotgun metaproteomic of low-diversity dairy microbiomes

The metaproteomics field has recently gained more and more interest as a valuable tool for studying both the taxonomy and function of microbiomes, including those used in food fermentations. One crucial step in the metaproteomics pipeline is selecting a database to obtain high-quality taxonomical and functional information from microbial communities. One of the best strategies described for building protein databases is using sample-specific or study-specific protein databases obtained from metagenomic sequencing. While this is true for high-diversity microbiomes (such as gut and soil), there is still a lack of validation for different database construction strategies in low-diversity microbiomes, such as those found in fermented dairy products where starter cultures containing few species are used. In this study, we assessed the performance of various database construction strategies applied to metaproteomics on two low-diversity microbiomes obtained from cheese production using commercial starter cultures and analyzed by LC-MS/MS. Substantial differences were detected between the strategies, and the best performance in terms of the number of peptides and proteins identified from the spectra was achieved by metagenomic-derived databases. However, extensive databases constructed from a high number of available online genomes obtained a similar taxonomical and functional annotation of the metaproteome compared to the metagenomic-derived databases. Our results indicate that, in the case of low-diversity dairy microbiomes, the use of publically available genomes to construct protein databases can be considered as an alternative to metagenome-derived databases.

Evaluating the Potential of Korean Mudflat-Derived Penicillium nalgiovense SJ02 as a Fungal Starter for Manufacturing Fermented Sausage.

The objective of this study was to isolate, identify, and evaluate novel Korean starter cultures for use in fermented sausages. A total of 72 strains were isolated from various indigenous sources, including Nuruk, Jeotgal, and mudflats on the west coast of South Korea. Two strains were identified as Penicillium nalgiovense (SD01 and SJ02), a traditional starter used in the production of fermented sausages. A comparative analysis was performed between SD01 and SJ02 using the commercial starter culture (M600). Strain SJ02 exhibited superior lipolytic and proteolytic activities, as well as an enhanced growth rate at the optimal salinity level of 2% NaCl compared to M600. No significant differences were observed in thiobarbituric acid reactive substances values, sausage colors, and texture properties between SJ02 and M600 fermented sausages, except for adhesiveness. Profiles of mycotoxin-related genes were similar for both strains. Electronic nose analysis revealed distinct aroma profiles between SJ02 and M600 fermented sausages, with a relatively higher levels of propan-2-one and butyl butanoate in SJ02, and a higher level of ethanol and propanal in M600. In electronic tongue analysis, there was no significant differences in taste characteristics between SJ02 and M600. These results indicate that P. nalgiovense SJ02 is a potential starter culture to produce dry fermented sausages, enhancing Korean style cured meat processing industry.

Biochemical characterization of YoAlp®: a sheep-fermented milk obtained with autochthonous starter cultures

Fermented milks are a source of bioactive peptides with different potential benefits on human health and may be considered as functional foods. Sheep milk and fermented milk have been collected and a biochemical characterization, by a proteomic approach, GC/MS and microtiter plate assay methods, have been conducted to evaluate their peptide, fatty acid and aromatic profile, and to assess potential health promoting effects. Furthermore, a comparison between sheep-fermented milk (SFM) made with commercial starter cultures and YoAlp®, a sheep-fermented milk obtained using local strains of lactic acid bacteria, has been performed. Peptide’s profile comparison shows a higher number of amino acidic frequencies using autochthonous starter cultures than commercial ones. Among these peptides, 20.78% and 29.87%, respectively, are supposed to be potentially bioactive. Furthermore, in both products, the fatty acid profile was similar to that of origin sheep milk, and concerning aromatic profile, YoAlp® shows yogurt typical aromatic assets. Considering bioactivity, ACE inhibitor activity is high for both samples. Similar values, as expected by peptide profile analysis, have been obtained. Even in the case of antioxidant capacity, peptide profile bioactivity prediction has been confirmed by the assay showing a DPPH inhibition higher for SFM than for YoAlp®, but this difference is not statistically significant. Local strains of lactic acid bacteria seem to work as well as the commercial, preserving biodiversity and typicality. However, further analyses are needed to understand microbial proteolytic activities and to investigate gastric digestion resistance of bioactive peptides.

Fourier Transform Infrared Spectroscopy Tracking of Fermentation of Oat and Pea Bases for Yoghurt-Type Products

The fermentation process of plant-based yoghurt (PBY)-like products must be followed for consistency by monitoring, e.g., the pH, temperature, and lactic acid concentration. Spectroscopy provides an efficient multivariate in situ quality monitoring method for tracking the process. Therefore, quality monitoring methods for pea- and oat-based yoghurt-like products using Fourier transform infrared (FT-IR) spectroscopy and high-performance liquid chromatography (HPLC) were developed and modeled. Plant-based yoghurt (PBY) was formulated by fermenting pea and oat plant drinks with a commercial starter culture based on Lactobacillus and Streptococcus strains. The main variance during fermentation was explained by spectral carbohydrate and protein bands with a notable shift in protein band peaks for the amide II band at 1548 cm−1 to 1576 cm−1. In addition to the identification of changed spectral bands during fermentation, FT-IR efficiently tracked the variation in oat and pea fermentation using pH as the main indicator. Prediction models with an R2 for the predicted value of pH as a fermentation indicator (R2 = 0.941) with a corresponding root-mean-squared error of prediction (RMSEP) of 0.247 was obtained when compared to the traditional pH method.

The aroma profile of butter produced using different starter cultures

The aroma of fermented dairy products is greatly influenced by starter cultures and by the lactic acid bacteria strains that are used as starter cultures. Experimental butter samples were produced using no starter culture, by a commercial starter culture (Lactococcus lactis subsp. lactis, Lactococcus lactis subsp. cremoris, Lactococcus lactis subsp. lactis biovar. diacetylactis, Leuconostoc mesenteroides), by a prepared bacteria mix (Lactococcus lactis subsp. lactis EM1, Lactococcus lactis subsp. cremoris EM28, Lactococcus lactis subsp. lactis biovar. diacetylactis G49, Leuconostoc mesenteroides B3), and by a prepared bacteria mix fortified with Lactobacillus rhamnosus B19 (L. rhamnosus B19). The aroma profile of the butter samples was investigated using a gas chromatography mass spectometry method (GC-MS). A total of 92 components were determined in the butter samples, including acids (12), alcohols (20), aldehydes (9), alkanes (6), esters (8), ketones (19) and several other aroma compounds (18). The sample containing the prepared starter culture had the most detectable aroma components, while the lowest number of aromatic components were found in the sample without a starter culture. 2,3-butanedione (diacetyl) was not detected in the sample without a starter culture. 2-Butanone 3-hydroxy- (acetoin) content was the highest in the sample containing the commercial starter culture and the lowest in the sample without a starter culture.

Oral Administration of Fermented Milk from Co-Starter Containing Lactobacillus plantarum Y44 Shows an Ameliorating Effect on Hypertension in Spontaneously Hypertensive Rats.

Fermented dairy foods such as yogurt exhibit some beneficial effects on consumers, including relieving the symptoms of hypertension. This study aims to obtain fermented dairy products from a co-starter that have a great flavor and the auxiliary function of reducing blood pressure after longtime consumption. Commercial starter cultures composed of Lactobacillus delbrueckii subsp. bulgaricus CICC 6047 and Streptococcus thermophilus CICC 6038 were combined with Lactobacillus plantarum strains Y44, Y12, and Y16, respectively, as a combined starter culture to ferment the mixed milk of skim milk and soybean milk. The fermented milk produced using the combined starter culture mixed with L. plantarum Y44 showed an angiotensin-converting-enzyme (ACE) inhibitory activity (53.56 ± 0.69%). Some peptides that regulate blood pressure were released in the fermented milk, such as AMKPWIQPK, GPVRGPFPII, LNVPGEIVE, NIPPLTQTPV, and YQEPVL. In spontaneously hypertensive rat (SHR) oral-administration experiments compared with the gavage unfermented milk group, the gavage feeding of SHRs with the fermented milk produced using the combined starter culture mixed with L. plantarum Y44 significantly reduced the blood pressure of the SHRs after long-term intragastric administration, shown with the systolic blood pressure (SBP) and diastolic blood pressure (DBP) decreasing by 23.67 ± 2.49 mmHg and 15.22 ± 2.62 mmHg, respectively. Moreover, the abundance of short-chain fatty acids (SCFA), bacterial diversity in the gut microbiota, and SCFA levels including acetic acid, propionic acid, and butyric acid in the feces of the SHRs were increased via oral administration of the fermented milk produced using the combined starter culture containing L. plantarum Y44. Furthermore, the ACE-angiotensin II (Ang II)-angiotensin type 1 (AT 1) axis was downregulated, the angiotensin-converting-enzyme 2 (ACE 2)-angiotensin(1-7) (Ang1-7)-Mas receptor axis of the SHRs was upregulated, and then the RAS signal was rebalanced. The fermented milk obtained from the combined starter culture shows the potential to be a functional food with antihypertension properties.

Investigating the effect of commercial starter cultures on the physicochemical and microbiological properties of Merguez, an artisanal Moroccan sausage

Investigating the effect of commercial starter cultures on the physicochemical and microbiological properties of Merguez, an artisanal Moroccan sausage

Screening of Aroma-Producing Performance of Anticlostridial Lacticaseibacillus casei Strains

AbstractThe cheesemaking industry is increasingly interested in using adjunct cultures with potential aromatic and anticlostridial activities. In this study, 34 Lb. paracasei and 2 Lb. rhamnosus strains were isolated from a semi-hard cheese and characterized for their proteolytic, esterase, and anticlostridial activity. Moreover, the strains were inoculated in a curd-based medium and the volatile compounds in the headspace of samples were evaluated by solid-phase microextraction–GC–MS analysis. Proteolytic activity was present in 30 strains, whereas only one Lb. paracasei strain showed esterase activity. All strains inhibited Cl. sporogenes, Cl. beijerinckii, and Cl. butyricum, and 18 isolates inhibited at least one Cl. tyrobutyricum strain. Principal component analysis and clustering analysis based on the volatilome grouped strains into three groups. One of these groups was characterized by high amounts of acids and esters and clustered with control samples inoculated with commercial starter cultures, suggesting similarity in the aroma profile. Strains belonging to this group with inhibitory effects against Cl. tyrobutyricum might be exploited as autochthonous adjunct cultures for the reduction of late-blowing defects in semi-hard cheeses.

Development of a functional Greek sheep yogurt incorporating a probiotic Lacticaseibacillus rhamnosus wild-type strain as adjunct starter culture

Greek yogurt is a fermented dairy product of high nutritional value that can be used as a matrix for the delivery of probiotics. The aim of this study was to develop a new probiotic Greek sheep yogurt with upgraded quality and functional characteristics. To do this, yogurt was manufactured by fermenting pasteurized milk with the commercial starter culture (Streptococcus thermophilus (ST), Lactobacillus bulgaricus (LB)) together with a probiotic Lacticaseibacillus rhamnosus (LR) wild-type strain (probiotic yogurt; PY). As a control, yogurt manufactured with only the starter culture (ST, LB) was used (conventional yogurt; CY) The survival of all three lactic acid bacteria (LAB) species (ST, LB, and LR) was monitored throughout the products’ shelf life (storage at 4 °C for 25 days), and also following exposure to a static in vitro digestion model (SIVDM). The population dynamics of total aerobic plate count (APC), Enterobacteriaceae, yeasts and molds grown in both yogurts were also determined. The total antioxidant activity (AA) of yogurts was comparatively determined using in parallel two different assays, whereas the Folin-Ciocalteu assay was used to determine their total phenolic content (TPC). At each sampling day, yogurts were also evaluated for their pH, titratable acidity (TA) and main sensory characteristics. The population of probiotic LR remained stable during the shelf life (and above 108 CFU/g). Yogurt starters (ST, LB) were not detected following SIVDM, whereas LR (in PY) presented a reduction of about only one log. The AA and TPC of PY were found significantly higher than that of CY (P < 0.05). At the end of storage (25th day), neither pH nor TA differed significantly between the two yogurt types, while no fungal growth was observed in the PY. Consumer sensory analysis did not reveal important differences between the two yogurt types during their shelf life. To sum up, the novel yogurt was able to deliver to consumers a high number of probiotic cells (>108 CFU/g), presented increased antioxidant power, had an expanded shelf life, and maintained its good sensory attributes.

Vitamin B12 production in solubilized protein extract of bioprocessed wheat bran with Propionibacterium freudenreichii

Wheat bran, a nutrient-rich byproduct of wheat milling, has the potential to be used for the production of vitamin B12 (B12) in order to fortify plant-based foods that are lacking in this vitamin. This study aimed to investigate B12 production in the soluble extract of bioprocessed wheat bran using Propionibacterium freudenreichii. The optimal conditions for B12 production were found to be a bioprocessing time of 24 h, along with the use of a commercial starter culture of lactic acid bacteria and yeast, with pH adjusted from 4.0 to 6.4. The highest B12 production (55 ng/mL) was achieved within three days of fermentation. Cobalt supplementation (as CoCl2 or food-grade yeast extract) resulted in up to four-fold increase in B12 production. Similar results (50–70 ng/mL) were obtained when the processes were scaled up, with bioprocessing involving up to 15 kg and B12 fermentation involving up to 5 L, demonstrating the robustness of the procedure. Microbiological safety was ensured with the absence of Enterobacteriaceae in the extracts after bioprocessing and B12 fermentation. Overall, this study highlights the potential of under-utilized wheat bran as a raw material for producing B12-enriched bran extract, which can be used to fortify plant-based products in various food applications.

Assessment of the Physicochemical, Antioxidant, Microbial, and Sensory Attributes of Yogurt-Style Products Enriched with Probiotic-Fermented Aronia melanocarpa Berry Juice.

The aim() of this study was to create() various formulations of yogurt enriched with freeze()-dried adjuncts, namely() (i) probiotic Lactobacillus plantarum ATCC 14917 culture(), and (ii) L. plantarum ATCC 14917 fermented black chokeberry juice, along with a commercial() starter culture(). The goal was to enhance() functionality and optimize the nutritional() value() of the products. These new yogurt-style() formulations were subsequently() compared with commercially produced yogurt. All products demonstrated() favorable() physicochemical properties, and the probiotic strain() consistently() maintained viable() levels exceeding 7 log() cfu/g throughout() the entire() storage() period(). The fermented milk produced with the adjunct-free L. plantarum cells, as well as the yogurt produced with the proposed() lactobacilli-fermented chokeberry juice, exhibited the highest lactic acid() production() (1.44 g/100 g yogurt by the end of storage()). Levels of syneresis were observed at lower() values() in yogurt produced with freeze()-dried fermented chokeberry juice. Yogurts prepared() with the lactobacilli-fermented freeze()-dried chokeberry juice displayed elevated total() phenolic content() and antioxidant capacity() (25.74 µg GAE/g and 69.05 µmol TE/100 g, respectively()). Furthermore, sensory tests revealed a distinctive() fruity flavor() in samples incorporating fermented juice. The results demonstrate() that probiotic L. plantarum-fermented chokeberry juice enhances() both the antioxidant capacity() and the viability of beneficial() bacteria() in yogurt while it can be readily() applied and commercialized, especially in the form of a freeze()-dried formulation.