Lab Fermenter Research Articles

A further understanding of changes of wheat bran functionality induced by different types of probiotics fermentation: From molecules to regulation mechanism

Wheat bran (WB) was solid-state fermented by either Lacticaseibacillus rhamnosus (LGG), Levilactobacillus brevis (LB) or Lactiplantibacillus plantarum (LP), respectively, and then their corresponding physicochemical and metabolic characteristics were investigated. Current study revealed fermentation of either Lacticaseibacillus rhamnosus or Lactiplantibacillus plantarum quickly generated lactic acid, but not for Levilactobacillus brevis. Importantly, all LAB fermentation promoted total phenolic acids contents, fermentation of LB-WB led to the greatest total phenolic content, followed by LGG-WB, with the least for LP-WB. Moreover, LGG fermentation significantly increased levels of oleic acid, stearic acid and phosphoenolpyruvic acid on carbon metabolism and fatty acid biosynthesis, while LB fermentation mainly increased levels of L-phenylalanine, cholecalciferol, D-gluconic acid and D-glucarate with the influence on the entire metabolic pathway. In contrast, LP fermentation significantly decreased levels of alpha-ketoglutaric acid, cis-aconitic acid on the citrate cycle (TCA cycle). This study revealed their corresponding metabolic characteristics, which might highlight potentially individual nutritional aspects.

Quality of fermented pumpkin beverages under different fermentation conditions by Lactobacillus plantarumFNCC 020

SummaryDevelopment of health‐promoting natural products has received importance, and fermented pumpkin can be a viable option, mainly regarding its carotenoid contents. This study aimed to investigate the quality of fermented pumpkin beverages (FPB) under various fermentation conditions (control, T1 = 30 °C, 12 h; T2 = 30 °C, 18 h; T3 = 30 °C, 24 h; T4 = 40 °C, 12 h; T5 = 40 °C, 18 h; T6 = 40 °C, 24 h) by Lactobacillus plantarum. Cell count of lactic acid bacteria, pH, chemical quality (soluble solid, acidity, total sugar, total phenolic content, total flavonoid content, and antioxidant activity), carotenoid contents, and colour attributes (h*, chroma, L*, and yellowing index) of FPB samples were studied. As a result, LAB fermentation significantly affected acidity and total sugar of FPB samples, while it did not change pH and soluble solids significantly. Besides, carotenoid contents and colour attributes of FPB were not different during fermentation, indicating that L. plantarum fermentation retained carotenoids and maintained physical appearances. Regarding sugars and organic acids, their quantity changed due to fermentation and lactic acids increased greatly up to three times higher than control after 24 h of fermentation at 30 °C. Moreover, fermentation by L. plantarum improved total phenolic content, total flavonoid content, and antioxidant activity, and these may recommend FPB as a potential functional product.

Enhancing physicochemical properties, organic acids, antioxidant capacity, amino acids and volatile compounds for ‘Summer Black’ grape juice by lactic acid bacteria fermentation

To investigate the effect of lactic acid bacteria fermentation on the quality of ‘Summer Black’ grape juice, this study characterized the differences in physicochemical properties, organic acids, antioxidant capacity, amino acids and volatile compounds among different treatments. The results showed that the pH and total sugar of all fermentation groups were lower than those of the CK (control group) sample. ZR (Lactobacillus plantarum) sample had the highest DPPH and OH− scavenging ability, and the total phenol and total flavonoid content of SR (Streptococcus thermophilus) sample were increased by 5.2% and 4.1%, respectively. The contents of tartaric acid, malic acid, and citric acid were improved significantly by LAB fermentation. The content of Asp, Thr, Ser, Glu, and Gly in the SR sample was significantly higher than in the CK sample. Phenylethyl alcohol, lactic ethyl ester, L-menthol, citronellol, and nerol were produced by LAB fermentation, giving fruit and floral aroma, and streptococcus thermophilus has a higher potential to enhance the aromatic flavor of ‘Summer Black’ grape juice. 20 chemical indicators were determined to explain the differences between groups by OPLS-DA.

Fermentation of asparagus juice using selected probiotic Lactiplantibacillus plantarumJGS49 isolated from pickled asparagus: microbiological, physicochemical and flavour characteristics

SummaryThis study aims to screen LAB with excellent probiotic and fermentation properties, and investigate the effect on asparagus juice. Fifty strains were isolated and identified from pickled asparagus, and Lactiplantibacillus plantarum JGS49 was screened by multiple properties. Whole‐genome analysis indicated that L. plantarum JGS49 contains nineteen antibiotic resistance genes and was non‐toxic. Compared with unfermented asparagus juice, the fermentation of L. plantarum JGS49 significantly improved the antioxidant activity of asparagus juice, and also increased the contents of total flavonoids, phenols and organic acids. Seventy‐nine volatile compounds were identified during the fermentation of asparagus juice, among which sixteen differential compounds with aroma activity thresholds were obtained. The contents of alcohol, acid and phenol in asparagus juice were increased by lactic acid bacteria fermentation, while the contents of furan were decreased. LAB fermentation improved the overall acceptability of asparagus juice, enhanced its mushroom and floral flavour, and reduced the green flavour.

Impact of Different Carbon Sources on Volatile Organic Compounds (VOCs) Produced during Fermentation by Levilactobacillus brevis WLP672 Measured Using Proton Transfer Reaction Time-of-Flight Mass Spectrometry (PTR-ToF-MS).

Bacterial fermentation is considered to be a cost-effective means of generating desired flavour compounds from plant-based substrates. However, the wide range of substrates present in plants makes it challenging to understand how individual components impact on flavour volatile organic compound (VOC) production. To simplify this, a defined medium can be used to better understand VOCs production with regard to individual compounds. In the current study, the VOCs produced by the lactic acid bacterium, Levilactobacillus brevis WLP672, growing in a defined medium containing different carbon sources (either glucose (DM), fructose (DMFr) or citrate (DMCi)) under a range of fermentation conditions (time: 0, 7, and 14 days; and temperature: 25 and 35 °C) were assessed using proton transfer reaction time-of-flight mass spectrometry (PTR-ToF-MS). Among the detected mass peaks (m/z), after 7 days of fermentation, the concentrations of m/z 45.033 (t.i. acetaldehyde), m/z 49.011 (t.i. methanethiol), and m/z 89.060 (t.i. ethyl acetate) were significantly (p < 0.05) higher in DM at 35 °C than all other treatments at either temperature. The knowledge obtained will help to produce desirable LAB fermentation flavour VOCs or VOC mixtures that could be used in developing plant-based analogues with acceptable sensory properties.

Artificial Intelligence-Powered Optimization and Milk Permeate Upcycling for Innovative Sesame Milk with Enhanced Probiotic Viability and Sensory Appeal.

Consumer demand for plant-based alternatives drives innovation in nondairy beverages. This study explores the development of a novel sesame milk with enhanced functionality using an artificial neural network (ANN) and milk permeate integration. An ANN model effectively optimized water-based sesame milk (WSM) extraction, maximizing total solids (T.S.) recovery. The ANN model's predicted T.S. yield (99.65%) closely matched the actual value (95.18%), demonstrating its potential for optimizing high-yield production. Furthermore, milk permeate was incorporated (5:1 ratio) to create permeate-based sesame milk (PSM), which supported the growth of lactic acid bacteria, suggesting its potential as a growth medium for future probiotic applications. PSM also displayed superior nutritional value and sensory characteristics compared to WSM. These findings highlight the promise of ANN-powered optimization and milk permeate integration for creating innovative sesame milk alternatives with enhanced probiotic viability and sensory appeal. Future research should focus on ANN optimization of alternative-based-plant milk, including permeate-based sesame milk production, the health benefits of LAB fermentation, and consumer preferences for flavors and textures. Optimizing fermentation and LAB selection remain key for commercial success.

Characterization of vitamin D3 biotransformation by the cell lysate of Actinomyces hyovaginalis CCASU-A11-2

A former work conducted in our Lab, lead to in a effective scale up of vitamin D3 bioconversion into calcitriol by Actinomyces (A.) hyovaginalis isolate CCASU-A11-2 in Lab fermenter (14 L) resulting in 32.8 µg/100 mL of calcitriol. However, the time needed for such a bioconversion process was up to 5 days. Therefore, the objective of this study was to shorten the bioconversion time by using cell-free lysate and studying different factors influencing bioconversion. The crude cell lysate was prepared, freeze-dried, and primarily fractionated into nine fractions, of which, only three fractions, 50, 100, and 150 mM NaCl elution buffers showed 22, 12, and 2 µg/10 mL, calcitriol production, respectively. Ammonium sulfate was used for protein precipitation, and it did not affect the bioconversion process except at a concentration of 10%w/v. Secondary fractionation was carried out using 80 mL of the 50 mM NaCl elution buffer and the results showed the 80 mL eluent volume was enough for the complete elution of the active protein. The pH 7.8, temperature 28 °C, and 6 h reaction time were optimum for maximum calcitriol production (31 µg/10 mL). In conclusion, the transformation of vitamin D3 into calcitriol was successfully carried out within 6 h and at pH 7.8 and 28 °C using fractionated cell lysate. This process resulted in a 10-fold increase in calcitriol as compared to that produced in our previous study using a 14 L fermenter (32.8 µg/100 mL). Therefore, cell-free lysate should be considered for industrial and scaling up vitamin D3 bioconversion into calcitriol.

Process of making muffin from modified sweet potato flour made from sustainable raw material based Indonesian local resources

Modified sweet potato flour is sweet potato flour that has been enhanced to maintain and improve its quality, thereby reducing the overall consumption of sweet potato flour in Indonesia. Muffins, being a type of quick bread that requires only a small amount of gluten, are highly suitable for use with modified sweet potato flour. This research was carried out in two stages: Stage I involved the modification of sweet potato flour, and stage II consisted of formulating a mixture of wheat flour and modified sweet potato flour. The research employs a non-factorial Completely Randomized Design (CRD) for both of these two stages and the determine of the best treatments are conducted using De Garmo effectiveness index method. The modified flour (annealing, instant yeast fermentation, LAB fermentation, and acetic acid) was analyzed for various quality parameters. Once the best method for modifying sweet potato flour was determined, the second stage involved the preparation of muffins. The muffin (100:0, 75:25, 50:50, 25:75, and 0:100) were also analyzed for various quality. The final results indicated that the J3 treatment (LAB fermentation) was the most effective for modifying the flour, and the F2 treatment (75:25 ratio) was the best formulation for muffins.

Technological quality and fungal community of Kombucha fermented with hemp leaves and milky mushroom flour (Calocybe indica).

Kombucha is traditionally a non-alcoholic beverage whose production is dependent on culture and the various ingredients used as substrates for fermentation. The goal of our study was to apply hemp leaf and milky mushroom (Calocybe indica) flour as functional ingredients to enhance phytonutrient quality, along with using a microbial consortium highly symbiotic with these ingredients. The study determined the content of phytonutrients (phenolic and flavonoids content), antioxidant activity through percentage inhibition of DPPH radical scavenging activity (%), and microbial communities changes during fermentation. The microbial changes were evaluated by cell viable count (total bacteria, Lactic Acid Bacteria, and Yeast & Mold) and ITS in prepared kombucha (using red tea leaves, pandan leaves, and sucrose) supplemented with functional ingredients: T1 (hemp leaves (control)) and T2 (hemp leaves with milky mushroom flour). The results indicated that microbial consortium changed during fermentation. In the first 7 days, the levels of yeast and mold increased to 6.17 and 6.18 log CFU/mL, respectively. By day 21, the levels of both T1 and T2 continued to rise, reaching 7.78 and 7.82 log CFU/mL, respectively. The viable count of lactic acid bacteria in T1 and T2 gradually increased to 6.79 and 6.70 log CFU/mL, respectively, by day 14. These changes resulted in a marked decrease in pH value, reaching 3.63 and 3.23 in T1 and T2, respectively, by the end of the process (21 days). The total bacterial viable count decreased with an increase in the fermentation time. During fermentation, unique genera of tea fungus observed in T1 and T2 were 64% and 19%, respectively. At the beginning (0 days), the top five genera found in T1 were: g__Setophoma (25.91%), g__Macrocybe (14.88%), g__Cladosporium (7.81%), g__Phaeosphaeria (7.12%), g__Malassezia (6.63%), while the top five genera in T2 were g__Macrocybe (94.55%), g__Setophoma (1.87%), g__Cladosporium (0.77%), g__Phaeosphaeria (0.40%), g__Cordyceps (0.38%). However, on day 21 (end of the process), it was found that g__Dekkera had the highest relative abundance in both T1 and T2. In addition, the supplementation of the two ingredients affected the total phenolic and total flavonoid content of the treatments. At the end of the process, T2 showed values of 155.91 mg GAE/mL for total phenolics and 1.01 mg CE/mL for total flavonoids, compared to T1, which had 129.52 mg GAE/mL and 0.69 mg CE/mL, respectively. Additionally, the DPPH inhibition was higher in T1 (91.95%) compared to T2 (91.03%). The findings suggest that kombucha fermented with these innovative ingredients exhibited enhanced phytonutrients, and served as substrate for LAB and tea fungus fermentation, while limiting the growth of fungal genera and diversity of microbial consortium.

Construction of hypoallergenic microgel by soy major allergen β-conglycinin through enzymatic hydrolysis and lactic acid bacteria fermentation

Soy allergenicity is a public concern, and the combination of multiple processing methods may be a promising strategy for reducing soy allergenicity. In this study, a novel two-step enzymatic hydrolysis followed by lactic acid bacteria fermentation was proposed for the construction of hypoallergenic soybean protein microgel. β-Conglycinin was used as the main soy allergen. The effects of different enzymatic hydrolysis (Alcalase, Neutrase, and Protamex) and LAB fermentation on β-conglycinin microgel formation and its immunoreactivity were investigated. Results showed that the use of different enzymes and the attainment of different degrees of hydrolysis affected the particle distribution and zeta potential in the microgels and leads to differences in microstructure and immunoreactivity. All hydrolysates compared with intact protein accelerated the formation of gel during LAB fermentation. Among the three assayed enzymes, fermented Protamex hydrolysates at 60 min (PF-60) demonstrated a microgel with an overall reduced average particle size (741.20±7.18 nm), lower absolute values of zeta potential (10.43±0.65 mV), and regular gel network. The antigenicity and IgE-binding capacity decreased to the lowest value of 0.30 % and 6.93 %, respectively. Peptidomics and immunoinformatic analysis suggested that PF-60 disrupted 17/30, 16/44, and 23/75 epitopes in the α, α′, and β subunits, respectively. Unlike the LAB-fermented unhydrolyzed β-conglycinin disrupted epitopes mostly located at the loop domain, PF-60 primarily promoted the exposure and disruption of allergen epitopes with β-sheet structure located at the core barrel domain. These findings can provide new perspectives on the preparation of hypoallergenic soybean-gel products on edible particulate systems.

Probiotic fermentation enhances bioaccessibility of lycopene, polyphenols and antioxidant capacity of guava fruit (Psidium guajava L)

This study investigated bio-accessibility of lycopene and total polyphenols using simulated gastrointestinal digestion, in guava pulp (Psidium guajava L) pulp fermented with two probiotic LAB strains Lactococcus lactis subsp lactis and Lactobacillus casei. Physicochemical parameters, and antioxidant contents were also evaluated. Results indicated that LAB fermentation reduced the pH of pulp from 3.8 to 2.6, with increase of TA and reduced the TSS content of the pulp to 13.06 and 12.67◦Bx, respectively after 8 h of fermentation. Compositional analysis of fermented guava pulps indicated decrease in carbohydrates (29.6%), lipids (4.6%), moisture (19.7%) and slight increase in proteins (0.7%). The total poly phenolics (701mg/GAE/g) and DPPH radical scavenging activity (81%) was significantly (p < 0.05) higher in comparison to unfermented counterparts while Vitamin C content was not affected. Guava pulp fermented by both strains improved overall sensorial acceptability with no notable differences in sensory scores after storage under refrigerated conditions for up to 7 days. Simulated gastrointestinal digestion studies revealed that pulp fermentation substantially improved the bioaccessibility of total phenols by 70% and 63% and lycopene content by 13.33 and 12.24% in L. lactis and L. casei fermented pulp in comparison to control (unfermented pulp). DPPH free radical scavenging activities of the dialyzable fractions of fermented guava pulp were 71.3 and 69.3% respectively. Overall, the results of this study were encouraging and indicate that fermentation of guava pulp with LAB can potentially enhance bioactives and their subsequent bioaccessibility implying beneficial impacts upon consumption.

Effects of Streptococcus thermophilus Fermentation on the Flavors and Antioxidant Properties of Barley Juice

Lactic fermentation can improve the metabolic profile and functionality of juice, which is beneficial to human health. This study aimed to investigate the effect of Streptococcus thermophilus fermentation on the metabolic profiles and antioxidant activity of barley juice. The results demonstrated that S. thermophilus 7G10 dramatically increased the total titratable acidity and total phenolic and flavonoid contents in the barley juice after 24 h of fermentation. Only sixteen volatile compounds were detected in the fermented barley juice, including six acids, four ketones, three alcohols, and one aldehyde. In addition, based on non-targeted metabolomics, 30 important differential metabolites were screened among the 1460 non-volatile compounds. Notably, the barley juice fermented with S. thermophilus 7G10 had increased free radical (ABTS, DPPH, and O2−) scavenging activities. Furthermore, sensory evaluation showed that the barley juice fermented with S. thermophilus 7G10 was most attractive to consumers. These results show that LAB fermentation promotes the formation of volatile compounds and potentially enhances the antioxidant properties of barley juice.

Changes in physicochemical characteristics and metabolites in the fermentation of goji juice by Lactiplantibacillus plantarum

Untargeted and targeted metabolomics based on LC-MS/MS was applied here to investigate the changes in metabolites following Lactiplantibacillus plantarum (L. plantarum) fermentation of goji juice. The changes in physicochemical characteristics, free amino acid and organic acid levels were quantified. Total phenols, total flavonoids, and antioxidant activity were increased after these L. plantarum fermentation. 31 primary metabolites were screened out by comparison between two groups using multivariate statistical analysis. L. plantarum consumed reducing sugar and most varieties of amino acids. Gamma amino butyric acid (GABA) and phenylacetaldehyde were significantly accumulated via precursor of glutamate and phenylalanine, respectively. Indole-3-lactic acid (ILA) was the characteristic secondary metabolite after fermentation. There were 6.25 and 4.19 mg/L ILA accumulated after LP-D and LP-F fermentation, respectively, whereas it was not detected in goji juice. The accumulation of tyrosol was strain-dependent. Part of the bitter-taste amino acids, including l-methinoine, l-phenylalanine and tryptophan, were converted into their corresponding acetyl-derivatives, which represented umami or kokumi taste. Overall, fermentation by L. plantarum strains altered the metabolite profile and increased the levels of several biologically active substances of goji juice. These results deepen the understanding of L. plantarum metabolism, and the bioconversion associated with flavor and bioactive compounds unraveled here can be used as references in other plant-based materials for LAB fermentation.

Antioxidant Capacity Changes and Untargeted Metabolite Profile of Broccoli during Lactic Acid Bacteria Fermentation

The purpose of this study was to reveal the changes in total phenolic content and antioxidant capacity of broccoli, and an untargeted metabolomics approach was developed to investigate the effect of lactic acid bacteria fermentation on the metabolome of broccoli florets. The results showed that the total phenolic content and antioxidant capacity significantly increased after fermentation. The untargeted metabolite profile showed that the main chemical components of fermented and unfermented broccoli are lipids and lipid-like molecules, organic acids and derivatives and organoheterocyclic compounds. Univariate and multivariate statistical analyses of the identified metabolites showed some metabolites such as sorbitol are upregulated after fermentation, and that other metabolites such as l-malic acid are downregulated after fermentation. Moreover, metabolite pathway analyses were used to study the identification of subtle but significant changes among groups of related metabolites that cannot be observed with conventional approaches. KEGG pathway analysis showed that metabolites are mainly enriched in the glucagon signaling pathway, pyruvate metabolism, glycolysis/gluconeogenesis and fructose and mannose metabolism after fermentation, compared with raw broccoli. The results of this study can help to further our understanding of the impact of LAB fermentation on bioactivity changes in and the metabolites profile of fermented broccoli, and the application of fermented broccoli in health foods and special dietary foods.

Isolation and Identification of Lactic Acid Bacteria and Their Effects on the Off-odor of Burdocks.

Burdocks have diverse nutritional and pharmacological functions, but their unique odor is unwelcome. Here, the effect and mechanism of lactic acid bacteria fermentation on the off-odor of burdocks were investigated. The sensory evaluation showed that burdocks had earthy, musty, grassy, and pepper odors. 2-Isobutyl-3-methoxypyrazine (IBMP) and 2-secbutyl-3-methoxypyrazine (IPMP) mainly contributed to burdock's unique off-odor and were identified by gas chromatography-mass spectrometry combined with headspace-solid phase microextraction (HS-SPME-GC-MS) and relative odor activity value (ROAV) analysis. Weissella cibaria ZJ-5 from screened strains performed with the strongest ability to remove the off-odor and generate a fragrant odor, as determined by sensory evaluation. When incubated aerobically together with IBMP during fermentation, ZJ-5 degraded IBMP directly from 149.56 ± 0.72 to 71.55 ± 1.81 ng/mL. Additionally, linoleic acid content in fermented burdocks was significantly decreased compared with unfermented burdocks. (E,Z)-2,6-Nonadienal, which mainly contributed to fermented burdock's odor, may have been generated from linoleic acid during ZJ-5 fermentation, through the acid catalysis pathway. It indicated that LAB fermentation could improve burdock odor by degrading off-odor compounds and precursors and by generating new aldehydes.

Hierarchical Effects of Lactic Fermentation and Grain Germination on the Microbial and Metabolomic Profile of Rye Doughs.

A multi-omics approach was adopted to investigate the impact of lactic acid fermentation and seed germination on the composition and physicochemical properties of rye doughs. Doughs were prepared with either native or germinated rye flour and fermented with Saccharomyces cerevisiae, combined or not with a sourdough starter including Limosilactobacillus fermentum, Weissella confusa and Weissella cibaria. LAB fermentation significantly increased total titrable acidity and dough rise regardless of the flour used. Targeted metagenomics revealed a strong impact of germination on the bacterial community profile of sprouted rye flour. Doughs made with germinated rye displayed higher levels of Latilactobacillus curvatus, while native rye doughs were associated with higher proportions of Lactoplantibacillus plantarum. The oligosaccharide profile of rye doughs indicated a lower carbohydrate content in native doughs as compared to the sprouted counterparts. Mixed fermentation promoted a consistent decrease in both monosaccharides and low-polymerization degree (PD)-oligosaccharides, but not in high-PD carbohydrates. Untargeted metabolomic analysis showed that native and germinated rye doughs differed in the relative abundance of phenolic compounds, terpenoids, and phospholipids. Sourdough fermentation promoted the accumulation of terpenoids, phenolic compounds and proteinogenic and non-proteinogenic amino acids. Present findings offer an integrated perspective on rye dough as a multi-constituent system and on cereal-sourced bioactive compounds potentially affecting the functional properties of derived food products.

Aroma profiles of sweet cherry juice fermented by different lactic acid bacteria determined through integrated analysis of electronic nose and gas chromatography-ion mobility spectrometry.

Sweet cherries are popular among consumers, with a recent explosion in sweet cherry production in China. However, the fragility of these fruits poses a challenge for expanding production and transport. With the aim of expanding the product categories of sweet cherries that can bypass these challenges, in this study, we prepared sweet cherry juice fermented by three different lactic acid bacteria (LAB; Lactobacillus acidophilus, Lactobacillus plantarum, and Lactobacillus rhamnosus GG), and evaluated the growth, physiochemical, and aroma characteristics. All three strains exhibited excellent growth potential in the sweet cherry juice; however, Lactobacillus acidophilus and Lactobacillus plantarum demonstrated more robust acid production capacity and higher microbial viability than Lactobacillus rhamnosus GG. Lactic acid was the primary fermentation product, and malic acid was significantly metabolized by LAB, indicating a transition in microbial metabolism from using carbohydrates to organic acids. The aroma profile was identified through integrated analysis of electronic nose (E-nose) and headspace gas chromatography-ion mobility spectrometry (HS-GC-IMS) data. A total of 50 volatile compounds characterized the aromatic profiles of the fermented juices by HS-GC-IMS. The flavor of sweet cherry juice changed after LAB fermentation and the fruity odor decreased overall. Lactobacillus acidophilus and Lactobacillus plantarum significantly increased 2-heptanone, ethyl acetate, and acetone contents, bringing about a creamy and rummy-like favor, whereas Lactobacillus rhamnosus GG significantly increased 2-heptanone, 3-hydroxybutan-2-one, and 2-pentanone contents, generating cheesy and buttery-like odors. Principal component analysis of GC-IMS data and linear discriminant analysis of E-nose results could effectively differentiate non-fermented sweet cherry juice and the sweet cherry juice separately inoculated with different LAB strains. Furthermore, there was a high correlation between the E-nose and GC-IMS results, providing a theoretical basis to identify different sweet cherry juice formulations and appropriate starter culture selection for fermentation. This study enables more extensive utilization of sweet cherry in the food industry and helps to improve the flavor of sweet cherry products.

Influence of LAB Fermentation on the Color Stability and Oxidative Changes in Dry-Cured Meat

Consumption of food products with a high level of compounds that are products of fat or protein oxidation is associated with the onset of various diseases. Therefore, this study estimated the level of oxidation in a fermented long-maturing tenderloin inoculated with lactic acid bacteria strains. To estimate the level of fat and protein exposure to oxidative factors, thiobarbituric acid reactive substances (TBARS), oxidation–reduction potential (ORP), oxygenation index (Oxi) as well as surface hydrophobicity (HS) of protein, and the content of free sulfhydryl (SH) groups were used as indicators of oxidation status. To validate the results, changes in the color of the products were determined using instrumental methods. This study confirmed the relationship between fat oxidation (based on TBARS) and oxidation of myoglobin as a protein representative (based on Oxi). Indeed, statistical analysis showed that TBARS, Oxi and SH were correlated with each other and could be used as indicators of oxidation in fermented products. The findings of this study also showed the use of LAB as starter cultures for meat fermentation may have an impact on the level of oxidation; in particular, the BAUER strain showed a protective effect on proteins in the final stages of the production of dry-cured pork loins.

Development and Chemical-Sensory Characterization of Chickpeas-Based Beverages Fermented with Selected Starters.

Legume protein ingredients are receiving continuous interest for their potential to formulate plant-based dairy analogs. In this study, a legume-based slurry was produced from an Apulian black chickpeas (BCP) protein concentrate and fermented with three starter cultures, Streptococcus&amp;nbsp;thermophilus (ST), a co-culture of ST with Lactococcus&amp;nbsp;lactis (STLL) and a co-culture of ST with Lactobacillus&amp;nbsp;plantarum (STLP). The effect of fermentation on the biochemical, texture and sensorial parameters was evaluated. The same beverage without inoculum was used as a control (CTRL). All the obtained fermented beverages were characterized by high protein (120.00 g kg-1) and low-fat contents (17.12 g kg-1). Fermentation contributed to a decrease in the contents of phytic acid by 10 to 79% and saturated fatty acids by 30 to 43%, with the STLP fermentation exercising the major effect. The three culture starters influenced the texture and sensorial attributes and the profile of the volatile compounds differently. Fermentation increased the lightness, consistency, cohesivity and viscosity of the formulated beverages. On a sensorial level, STLL had a major effect on the acidity, sourness and astringency, while both ST and STLP affected the creaminess, solubility and stickiness. Legumes and grass aromas were masked in LAB-fermented samples, probably due to a new VOC formation. The functional properties of LAB fermentation, along with the high protein content of the black chickpeas concentrate, provide the opportunity to formulate a clean label and safe plant-based fermented beverage with higher nutritional value compared to the others currently found in the market.

Fermentation of ginkgo biloba kernel juice using Lactobacillus plantarum Y2 from the ginkgo peel: Fermentation characteristics and evolution of phenolic profiles, antioxidant activities in vitro, and volatile flavor compounds.

In this study, a strain of Lactobacillus plantarum Y2 was isolated from the ginkgo peel, and showed adequate adaptation to the ginkgo biloba kernel juice. After 48 h of fermentation, the number of viable cells in the stable growth phase was remained at 10.0 Log CFU/mL, while the content of total organic acid increased by 5.86%. Phenolic substances were significantly enriched, and the content of total phenolic substances increased by 9.72%, and the content of total flavonoids after fermentation exceeded 55.33 mg/L, which was 3.6 times that of the unfermented ginkgo juice. The total relative content of volatile flavor compounds increased by 125.48%, and 24 new volatile flavor substances were produced. The content of total sugar, total protein, and total free amino acid decreased to 44.85, 67.51, and 6.88%, respectively. Meanwhile, more than 82.25% of 4'-O-methylpyridoxine was degraded by lactic acid fermentation, and the final concentration in ginkgo biloba kernel juice was lower than 41.53 mg/L. In addition, the antioxidant and antibacterial activities of fermented ginkgo biloba kernel juice were significantly enhanced. These results showed that LAB fermentation could effectively improve the nutritional value and safety of ginkgo biloba kernel juice.