Controlled fermentation of curly kale juice with the use of autochthonous starter cultures

Studies on the Effects of Fermentation on the Phenolic Profile and Biological Activity of Three Cultivars of Kale

Fermentation is used not only to preserve food but also to enhance its beneficial effects on human health and achieve functional foods. This study aimed to investigate how different treatments (spontaneous fermentation or fermentation with the use of starter culture) affect phenolic content, antioxidant potential, and cholinesterase inhibitory activity in different kale cultivars: 'Halbhoner Grüner Krauser', 'Scarlet', and 'Nero di Toscana'. Chosen samples were further tested for their protective potential against the Caco-2 cell line. HPLC-MS analysis revealed that the fermentation affected the composition of polyphenolic compounds, leading to an increase in the content of rutin, kaempferol, sinapinic, and protocatechuic acids. In general, kale cultivars demonstrated various antioxidant activities, and fermentation led to an increase in total phenolic content and antioxidant activity. Fermentation boosted anti-cholinesterase activity most profoundly in 'Nero di Toscana'. Extracts of spontaneously fermented 'Scarlet' (SS) and 'Nero di Toscana' (NTS) showed cytoprotective properties, as revealed by the malondialdehyde (MDA), lactate dehydrogenase (LDH), superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH) assays. Additionally, strong anti-inflammatory activity of NTS was shown by decreased release of cytokines IL-1β and TNF-α. Collectively, the conducted studies suggest fermented kale cultivars as a potential source for functional foods.

Effect of mixed fermentation of Lactiplantibacillus plantarum and Lactiplantibacillus pentosus on phytochemical and flavor characteristics of Wallace melon juice

BACKGROUND

Melons (Cucumis melo L.) are among the most commonly consumed fruits but they are highly susceptible to mechanical damage and rot during storage and transportation. New processed products are needed to avoid postharvest fruit loss and to increase health benefits. Fermentation is an effective means of utilizing the nutrients and improving flavor.

RESULTS

Fermented melon juice (MJ) was prepared using three potential probiotics Lactiplantibacillus plantarum CICC21824 (LP), Lactiplantibacillus plantarum GB3-2 (LG), and Lactiplantibacillus pentosus XZ-34 (LX). The nutrition, flavor characteristics, and digestive properties of different fermented MJs were compared. The results demonstrated that, in comparison with mono-fermentation, mixed fermentation by LG and LX could increase the level of organic acids and phenolic acids. Correspondingly, antioxidant capacity was improved significantly and positively correlated with p-coumaric acid and cinnamic acid content. The production of alcohols and acids was more strongly enhanced by mixed culture fermentation, whereas mono-fermentation reduced the content of esters, especially ethyl acetate and isopropyl acetate. Aldehydes and ketones increased significantly in fermented MJ, and damascenone and heptanal could be the characteristic aroma compounds.

CONCLUSION

Mixed fermented MJ provides more beneficial phytochemicals, better flavor, and stronger antioxidant properties than mono-fermentation. © 2024 Society of Chemical Industry.

Conversion of (poly)phenolic compounds in food fermentations by lactic acid bacteria: Novel insights into metabolic pathways and functional metabolites

Lactobacillaceae are among the major fermentation organisms in most food fermentations but the metabolic pathways for conversion of (poly)phenolic compounds by lactobacilli have been elucidated only in the past two decades. Hydroxycinnamic and hydroxybenzoic acids are metabolized by separate enzymes which include multiple esterases, decarboxylases and hydroxycinnamic acid reductases. Glycosides of phenolic compounds including flavonoids are metabolized by glycosidases, some of which are dedicated to glycosides of plant phytochemicals rather than oligosaccharides. Metabolism of phenolic compounds in food fermentations often differs from metabolism in vitro, likely reflecting the diversity of phenolic compounds and the unknown stimuli that induce expression of metabolic genes. Current knowledge will facilitate fermentation strategies to achieve improved food quality by targeted conversion of phenolic compounds.

Changes in the content of glucosinolates, polyphenols and carotenoids during lactic-acid fermentation of cruciferous vegetables: a mini review

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Cruciferous vegetables as fermented products has been used since ancient times.

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During fermentation of cruciferous vegetables complete fermentation of glucosinolates occur.

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Fermentation decrease the content of complex polyphenols, while increase the content of polyphenols in free form.

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Carotenoid content decrease during fermentation of cruciferous vegetables.

Cruciferous vegetables are considered functional foods because of their content of health-related compounds. They are grown and consumed in various cultures around the world. Fermentation as a preservation method for cruciferous vegetables has been used since ancient times. This process results in fermented products that have a unique flavour and odour, high bioactivity, and a distinctly different phytochemical profile than raw vegetables. In this mini review, we summarize data on changes in phytochemical content during lactic-acid fermentation of various cruciferous vegetables. The main focus was on the changes in the group of glucosinolates, polyphenols and carotenoids.

Pasta with Kiwiberry (Actinidia arguta): Effect on Structure, Quality, Consumer Acceptance, and Changes in Bioactivity during Thermal Treatment

In this study, kiwiberry lyophilizate (KBL) was incorporated into pasta at different levels (5%, 10%, and 15% w/w). Kiwiberry fruits’ characteristics (ascorbic acid, carotenoids, phenolic compounds, and antioxidant activity determination) as well as physical (cooking properties, color, microscopic structure determination, texture, and water molecular dynamics analysis by low-field NMR) and chemical analyses (proximate composition phenolic compounds composition and antioxidant activity) of KBL-enriched pasta were investigated. The replacement of semolina with KBL in the production of pasta significantly changed its culinary properties. Results showed that the addition of KBL leads to a reduction in optimal cooking time and cooking weight (47.6% and 37.3%, respectively). Additionally, a significant effect of the KBL incorporation on the color of both fresh and cooked pasta was observed. A significant reduction in the L* value for fresh (27.8%) and cooked (20.2%) pasta was found. The KBL-enriched pasta had a different surface microstructure than the control pasta and reduced firmness (on average 44.7%). Low-field NMR results have confirmed that the ingredients in kiwiberry fruit can bind the water available in fresh pasta. The heat treatment resulted in increasing the availability of phenolic compounds and the antioxidant activity (64.7%) of cooked pasta. Sensory evaluation scores showed that the use of 5–10% of the KBL additive could be successfully accepted by consumers.

Effects of the Probiotic, Lactobacillus delbrueckii subsp. bulgaricus, as a Substitute for Antibiotics on the Gastrointestinal Tract Microbiota and Metabolomics Profile of Female Growing-Finishing Pigs

Lactobacillus delbrueckii subsp. bulgaricus (LDB) is an approved feed additive on the Chinese ‘Approved Feed Additives’ list. However, the possibility of LDB as an antibiotic replacement remains unclear. Particularly, the effect of LDB on microbiota and metabolites in the gastrointestinal tract (GIT) requires further explanation. This study aimed to identify the microbiota and metabolites present in fecal samples and investigate the relationship between the microbiota and metabolites to evaluate the potential of LDB as an antibiotic replacement in pig production. A total of 42 female growing-finishing pigs were randomly allocated into the antibiotic group (basal diet + 75 mg/kg aureomycin) and LDB (basal diet + 3.0 × 109 cfu/kg LDB) groups. Fecal samples were collected on days 0 and 30. Growth performance was recorded and assessed. 16S rRNA sequencing and liquid chromatography-mass spectrometry-based non-targeted metabolomics approaches were used to analyze the differences in microbiota and metabolites. Associations between the differences were calculated using Spearman correlations with the Benjamini−Hochberg adjustment. The LDB diet had no adverse effect on feed efficiency but slightly enhanced the average daily weight gain and average daily feed intake (p > 0.05). The diet supplemented with LDB increased Lactobacillus abundance and decreased that of Prevotellaceae_NK3B31_group spp. Dietary-supplemented LDB enhanced the concentrations of pyridoxine, tyramine, D-(+)-pyroglutamic acid, hypoxanthine, putrescine and 5-hydroxyindole-3-acetic acid and decreased the lithocholic acid concentration. The Lactobacillus networks (Lactobacillus, Peptococcus, Ruminococcaceae_UCG-004, Escherichia-Shigella, acetophenone, tyramine, putrescine, N-methylisopelletierine, N1-acetylspermine) and Prevotellaceae_NK3B31_group networks (Prevotellaceae_NK3B31_group, Treponema_2, monolaurin, penciclovir, N-(5-acetamidopentyl)acetamide, glycerol 3-phosphate) were the most important in the LDB effect on pig GIT health in our study. These findings indicate that LDB may regulate GIT function through the Lactobacillus and Prevotellaceae_NK3B31_group networks. However, our results were restrained to fecal samples of female growing-finishing pigs; gender, growth stages, breeds and other factors should be considered to comprehensively assess LDB as an antibiotic replacement in pig production.