Fermentation by Probiotic Lactobacillus gasseri Strains Enhances the Carotenoid and Fibre Contents of Carrot Juice

Evaluation of sapodilla pulp as a matrix for probiotic fermentation: Physicochemical changes, antioxidant potential, and in vitro digestibility during storage

This study investigated the influence of three probiotic strains (Lacticaseibacillus paracasei subsp. paracasei, Bifidobacterium animalis subsp. lactis, and Lacticaseibacillus rhamnosus) on the fermentation of sapodilla pulp, assessing its bioactive and antioxidant potential, in vitro digestibility, and stability during 28 days of storage. The sapodilla pulp, with high moisture (72.13 %), fiber (6.27 %), and sugars (14.70 % total, 8.96 % reducing), provided a protective matrix for probiotics. Fermentation at 35 °C for 24 h resulted in significant microbial growth, with L. rhamnosus exhibiting the highest viable cell count (8.90 log CFU/g), followed by B. animalis (8.70 log CFU/g) and L. paracasei (8.49 log CFU/g). HPLC analysis revealed substantial glucose and fructose depletion, particularly in L. rhamnosus-fermented samples. Throughout storage, pH (5.10-5.90) and total soluble solids (19.60-19.9°Brix) decreased, while cell viability remained stable (8-9 CFU/g). Fermentation enhanced bioactive compounds, with increased total phenolic content (TPC), β-carotene, and lycopene, the latter peaking at 14 days in B. animalis (45.72 μg/100 g). Antioxidant capacity improved across assays (ABTS, FRAP, and DPPH), with DPPH showing the highest values (2.19-2.85 μM TE/g). Simulated digestion revealed viability loss in oral and gastric phases but a marked recovery in the intestinal phase, where L. rhamnosus demonstrated superior resistance and regrowth. These findings emphasize the role of sapodilla pulp in enhancing probiotic stability and functionality, positioning it as a promising matrix for functional food development with potential health and economic benefits.

Lactic acid bacterial fermentation as a biotransformation strategy to enhance the bioavailability of phenolic antioxidants in fruits and vegetables: A comprehensive review

Fruits and vegetables (FVs) are rich sources of macro and micro-nutrients crucial for a healthy diet. In addition to these nutrients, FVs also contain fibre and phytochemicals known for their antioxidant properties. Despite the growing evidence of the disease-preventive role of antioxidants in FVs, their bioavailability and bioaccessibility vary significantly and have not been adequately explored. Lactic acid bacterial (LAB) fermentation is considered the most appropriate and accessible biotechnological approach to maintain and enhance the safety, nutritional, sensory and shelf-life properties of perishable foods such as FVs. This review critically assesses how LAB fermentation could be utilised as a promising biotransformation strategy to enhance the bioavailability of antioxidants in FVs. Furthermore, it discusses the potential use of uniquely nutritious Australian native fruits as suitable candidates for LAB fermentation. Further research is essential to identify the beneficial properties of bioactive compounds and effective LAB-based biotransformation strategies to improve the bioavailability and bioaccessibility of antioxidants in FVs.

Effects of different lactic acid bacteria on the physicochemical properties, functional characteristics and metabolic characteristics of fermented hawthorn juice

Lactic acid bacteria (LAB) fermentation enhances the flavour and functionality of juice substrates; however, research on hawthorn juice is limited. We hypothesize that due to strain specificity, the changes in hawthorn juice after fermentation with different LAB may vary. After selecting LAB strains based on pH and sensory evaluation, the physicochemical properties and anti-inflammatory potential in a lipopolysaccharide-induced RAW 264.7 macrophage model were analysed in vitro. Non-targeted metabolomics revealed fermentation-driven metabolic changes. All strains exhibited increased total acidity and decreased reducing sugar and flavonoid contents. In particular, the Lactobacillus plantarum SC-1.3 and FWDG (strain preservation number) strains suppressed the pro-inflammatory cytokines interleukin-6 and tumour necrosis factor-α, with FWDG exhibiting the strongest effect. Moreover, fermentation resulted in the enrichment of bioactive metabolites, including prunetin and glycitein, which are unique to FWDG. The results provided a basis for the industrialization of hawthorn juice as a dietary product.

Untargeted metabolomics reveals flavor and metabolic changes in mixed Lactobacillus-fermented black mulberry juice

This study aimed to investigate metabolic differences between mixed- and single-culture fermentation in black mulberry juice (BMJ). Using E-nose, E-tongue, and metabolomics, we analyzed metabolic profile variations and flavor compounds in BMJ fermented with different lactic acid bacteria (LAB). Results demonstrated that BMJ is an excellent fermentation substrate, with both cultures achieving colony counts exceeding 8 log CFU/mL after fermentation. Volcano plot and cluster analyses revealed that single-culture fermentation exhibited higher efficiency in biotransforming and degrading specific compounds, yet its metabolic profile was less diverse. In contrast, mixed-culture fermentation enhanced metabolic diversity through complementary pathways among strains, improving complex molecule production, optimizing flavors, reducing bitterness/astringency, and minimizing vitamin loss. This research provides a foundation for fermented mulberry beverage development. Future studies could integrate multi-omics analyses to advance industrial applications.

Comparative bioavailability of β-carotene from raw carrots and fresh carrot juice in humans: a crossover study

BACKGROUND/OBJECTIVES

Carrots are a major source of beta-carotene, but comparative studies on different consumption methods are limited. This study compared the rates of β-carotene absorption from fresh carrots versus fresh carrot juice.

SUBJECTS/METHODS

For β-carotene absorption, a separate randomized controlled crossover trial was conducted with 16 healthy adults. The participants consumed 25 mg of β-carotene from raw carrots or fresh carrot juice. Blood samples were collected at the baseline (0 h) and at 0.5, 1, 1.5, 2, 3, 4, 6, 8, 12, and 24 h post-consumption.

RESULTS

The carrot juice group exhibited 2.33 times higher peak plasma concentrations 1.5 h post-consumption than those in the raw carrot group. The area under the curve for β-carotene absorption was 2.09 times greater in the carrot juice group than in the raw carrot group. The plasma α-carotene levels increased in both groups, but no significant differences were found. Similarly, no significant changes in the plasma levels of other fat-soluble vitamins were observed. In addition, no significant differences in antioxidant capacity (oxygen radical absorbance capacity and total radical-trapping antioxidant potential) were found between the 2 groups.

CONCLUSION

Consuming fresh carrot juice, without added sugars, may enhance the bioavailability of β-carotene compared to raw produce.

Expanding our food supply: underutilized resources and resilient processing technologies

Many underutilized food resources have been traditionally used by regional and poor communities. The history of their consumption makes them potential new food sources for incorporation into the wider food supply. The ability to tap the potential of undervalued and underutilized food sources will reduce the world's reliance on a limited number of food sources and improve food security and sustainability. The expansion of the food diversity of the food supply to include underutilized food resources will require overcoming challenges in the efficient and profitable production of the raw material, application of suitable postharvest handling procedures to maintain the quality of perishable produce, and the use of appropriate traditional and emerging food processing technologies for conversion of the raw material into safe, nutritious and consumer-acceptable foods. Improvement of food processing technologies, particularly resource-efficient resilient food processes, are required to ensure the safety, quality and functionality of the whole food or extracts, and to develop ingredient formulations containing new foods for manufacture of consumer food products. Factors that help facilitate the social acceptance of new underutilized foods include increasing consumer knowledge and understanding of the contribution of new underutilized food resources to diet diversity for good nutrition, confidence in the safety and value of new foods, and their low environmental impact and importance for future sustainable food. The introduction of new underutilized food resources will increasingly require collaboration along the whole food value chain, including support from government and industry. © 2024 The Author(s). Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Metabolomic changes in Citrus reticulata peel after conventional and ultrasound-assisted solid-state fermentation with Aspergillus niger: A focus on flavonoid metabolism

This study explored the changes in nutrients, metabolites, and enzyme activity in Citrus reticulata peel powders (CRPP) under conventional or ultrasound-assisted solid-state fermentation (SSF) using Aspergillus niger CGMCC 3.6189. Compared to nonfermented CRPP (NF-CRPP), ultrasound-assisted fermented CRPP (UIS-CRPP) significantly increased total protein and carotenoid levels by 85.26 % and 179.68 %, respectively, surpassing conventionally-fermented CRPP (FO-CRPP). Among the 521 identified differential metabolites, organic acids, lipids, and flavonoids were predominant. Flavonoid accumulation was primarily driven by the flavone and flavonol biosynthesis pathway, with 90.47 % and 90.00 % of differential flavonoids upregulated in FO-CRPP and UIS-CRPP, respectively. SSF significantly increased phenylalanine, tyrosine, and methionine levels, and tyrosine ammonia-lyase and β-D-glucosidase activities, with higher levels in UIS-CRPP. These findings suggest that conventional and ultrasound-assisted fermentation enhances flavonoid levels in CRPP by modulating key enzyme activities in flavonoid biosynthesis and biotransformation. Our study offers a feasible approach for producing value-added products from citrus peel waste.

Metabolomics analysis of okara probiotic beverages fermented with Lactobacillus gasseri and Limosilactobacillus fermentum by LC-QTOF-MS/MS

In this study, okara was fermented with probiotic strains Lactobacillus gasseri LAC 343 and Limosilactobacillus fermentum PCC, respectively. Significant increases in cell count (by 2.22 log CFU/mL for LAC and 0.82 log CFU/mL for PCC) and significant decreases in pH (by 1.31 for LAC and 1.03 for PCC) were found in fermented okara slurry. In addition, strain LAC tended to produce amino acids, while strain PCC depleted most amino acids. An untargeted metabolomic-based approach using liquid chromatography coupled with quadrupole time-of-flight mass spectrometry was used to further understand the compositional changes and potential health benefits by identifying bioactive metabolites in fermented okara slurry. We successfully identified various beneficial bioactive compounds including γ-aminobutyric acid, indolelactic acid, d-phenyllactic acid, and p-hydroxyphenyllactic acid which had differences in fold-changes in okara slurry fermented with different strains. Our study indicated the feasibility of using probiotics to ferment okara for novel functional food development.

An overview of fermentation in the food industry - looking back from a new perspective

Fermentation is thought to be born in the Fertile Crescent, and since then, almost every culture has integrated fermented foods into their dietary habits. Originally used to preserve foods, fermentation is now applied to improve their physicochemical, sensory, nutritional, and safety attributes. Fermented dairy, alcoholic beverages like wine and beer, fermented vegetables, fruits, and meats are all highly valuable due to their increased storage stability, reduced risk of food poisoning, and enhanced flavor. Over the years, scientific research has associated the consumption of fermented products with improved health status. The fermentation process helps to break down compounds into more easily digestible forms. It also helps to reduce the amount of toxins and pathogens in food. Additionally, fermented foods contain probiotics, which are beneficial bacteria that help the body to digest food and absorb nutrients. In today's world, non-communicable diseases such as cardiovascular disease, type 2 diabetes, cancer, and allergies have increased. In this regard, scientific investigations have demonstrated that shifting to a diet that contains fermented foods can reduce the risk of non-communicable diseases. Moreover, in the last decade, there has been a growing interest in fermentation technology to valorize food waste into valuable by-products. Fermentation of various food wastes has resulted in the successful production of valuable by-products, including enzymes, pigments, and biofuels.

Impact of Fermentation Conditions on Physicochemical Properties, Antioxidant Activity, and Sensory Properties of Apple-Tomato Pulp

The aim of the study was to optimize the conditions [inoculum size (4, 6, and 8%), fermentation temperature (31, 34, and 37 °C), and apple: tomato ratio (2:1, 1:1, and 1:2)] on the viable cell count and sensory evaluation in apple-tomato pulp by response surface methodology (RSM), and determine the physicochemical properties, antioxidant activity, and sensory properties during fermentation. The optimal treatment parameters obtained were an inoculum size of 6.5%, a temperature of 34.5 °C, and an apple: tomato ratio of 1:1. After fermentation, the viable cell count reached 9.02 lg(CFU/mL), and the sensory evaluation score was 32.50. During the fermentation period, the pH value, total sugar, and reducing sugar decreased by 16.67%, 17.15%, and 36.05%, respectively. However, the total titratable acid (TTA), viable cell count, total phenol content (TPC), and total flavone content (TFC) increased significantly by 13.64%, 9.04%, 21.28%, and 22.22%, respectively. The antioxidant activity [2,2-diphenyl-1-picrylhydrazyl (DPPH) free-radical scavenging ability, 2,2'-azino-di(2-ethyl-benzthiazoline-sulfonic acid-6) ammonium salt (ABTS) free-radical scavenging ability, and ferric-reducing antioxidant capacity power (FRAP)] also increased by 40.91%, 22.60%, and 3.65%, respectively, during fermentation. A total of 55 volatile flavour compounds were detected using HS-SPME-GC-MS among the uninoculated samples and fermented samples before and after fermentation. The results showed that fermentation increased the types and total amount of volatile components in apple-tomato pulp, and eight new alcohols and seven new esters were formed. Alcohols, esters, and acids were the main volatile components in apple-tomato pulp, accounting for 57.39%, 10.27%, and 7.40% of the total volatile substances, respectively.

Recent Innovations in Non-dairy Prebiotics and Probiotics: Physiological Potential, Applications, and Characterization

Non-dairy sources of prebiotics and probiotics impart various physiological functions in the prevention and management of chronic metabolic disorders, therefore nutraceuticals emerged as a potential industry. Extraction of prebiotics from non-dairy sources is economical and easily implemented. Waste products during food processing, including fruit peels and fruit skins, can be utilized as a promising source of prebiotics and considered "Generally Recognized As Safe" for human consumption. Prebiotics from non-dairy sources have a significant impact on gut microbiota and reduce the population of pathogenic bacteria. Similarly, next-generation probiotics could also be isolated from non-dairy sources. These sources have considerable potential and can give novel strains of probiotics, which can be the replacement for dairy sources. Such strains isolated from non-dairy sources have good probiotic properties and can be used as therapeutic. This review will elaborate on the potential non-dairy sources of prebiotics and probiotics, their characterization, and significant physiological potential.

Freeze dried probiotic carrot juice powder for better storage stability of probiotic

Probiotic strains isolated from Gundruk- a traditional Indian fermented food-and fermented carrot juice, were evaluated for their probiotic properties and analyzed probiotic properties such as lactic acid production, NaCl tolerance, and acid tolerance for all the isolated strains. Most isolated strains were susceptible to antibiotics, and cell-free extracts showed potential antioxidant activity and observed antagonistic properties against foodborne pathogens such as Salmonella typhi ATCC 6539, Escherichia coli ATCC 25922, Shigella ATCC 12022, and Staphylococcus ATCC 29213. The isolate Enterococcus faecalis(K13), was incorporated in carrot juice and microencapsulated by freeze-drying and spray drying. Gum Arabic and maltodextrin were used as coating materials. The physicochemical properties, such as bulk density, moisture content, water activity and color of the powders, and the survivability of probiotic bacteria, were studied on storage. The freeze-dried probiotic formulation is suggested over spray-dried formulation for further use, since it had good storage stability up to one month (6-7 Log CFU/g).

Recent advance in technological innovations of sugar-reduced products

Sugar is crucial as an essential nutrient for humans as well as for providing texture, sweetness and so on to food. But with the rise in people's pursuit of health, it is becoming increasingly clear that excessive consumption of sugar can locate a load on the body. It has been that excessive sugar is associated with many diseases, such as dental caries, obesity, diabetes, and coronary heart disease. Therefore, researchers and industries are trying to reduce or substitute sugar in food without affecting the sensory evaluation. Substituting sugar with sweeteners is alternatively becoming the most traditional way to minimize its use. So far, the sweeteners such as stevia and xylitol have been are commercially applied. Several studies have shown that technological innovation can partially compensate for the loss in sweetness as a result of sugar reduction, such as cross-modal interactions that stimulate sweetness with aroma, nanofiltration that filters disaccharides and above, enzyme-catalyzed sugar hydrolysis, and microbial fermentation that turns sugar into sugar alcohol. This review summarizes these studies to enhance the safety and quality of sugar-reduced products, and will provide some theoretical frameworks for the food industry to reduce sugar in foods, meet consumers' needs, and promote human health.

Manipulation of the diet-microbiota-brain axis in Alzheimer's disease

Several studies investigating the pathogenesis of Alzheimer's disease have identified various interdependent constituents contributing to the exacerbation of the disease, including Aβ plaque formation, tau protein hyperphosphorylation, neurofibrillary tangle accumulation, glial inflammation, and the eventual loss of proper neural plasticity. Recently, using various models and human patients, another key factor has been established as an influential determinant in brain homeostasis: the gut-brain axis. The implications of a rapidly aging population and the absence of a definitive cure for Alzheimer's disease have prompted a search for non-pharmaceutical tools, of which gut-modulatory therapies targeting the gut-brain axis have shown promise. Yet multiple recent studies examining changes in human gut flora in response to various probiotics and environmental factors are limited and difficult to generalize; whether the state of the gut microbiota in Alzheimer's disease is a cause of the disease, a result of the disease, or both through numerous feedback loops in the gut-brain axis, remains unclear. However, preliminary findings of longitudinal studies conducted over the past decades have highlighted dietary interventions, especially Mediterranean diets, as preventative measures for Alzheimer's disease by reversing neuroinflammation, modifying the intestinal and blood-brain barrier (BBB), and addressing gut dysbiosis. Conversely, the consumption of Western diets intensifies the progression of Alzheimer's disease through genetic alterations, impaired barrier function, and chronic inflammation. This review aims to support the growing body of experimental and clinical data highlighting specific probiotic strains and particular dietary components in preventing Alzheimer's disease via the gut-brain axis.

Effect of lactic acid fermentation on the nutritional quality and consumer acceptability of African nightshade

African nightshade (ANS) is among many underexploited and neglected indigenous vegetables. This study assessed the effect of lactic acid fermentation (LAF) on nutritional and sensory quality in Solanum villosum (Sv) and Solanum scabrum (Ss). Spontaneously fermented (SF) and controlled fermented (CF) conditions using Lactobacillus plantarum LP90 and Leuconostoc mesenteroides LM58 were employed for 15 days and 120 h. From the fermented pickles, relish products were prepared using cooking oil and a variety of spices. The relish products were subjected to a consumer acceptability test. Results show a significant drop in pH to <3.5, increasing titratable acidity (TTA) to around 0.6 after 120 h and 15 days of CF and SF, respectively. LAF resulted in a 2.6-5 and 1.6-4.8-fold significant rise in β-carotene in pickles and their relish products. All pickles and relish products exhibited a significant decrease (p < .05) in vitamin C by 88.33%-95.90%. LAF significantly reduced total phenolic (26%- 43%) and Chlorophyll (16.45%-39.25%). On the other hand, LAF showed improvement in minerals content (P, Ca, Fe, and Zn) and reduction of tannin (76.27%-92.88%) and oxalate (77.33%-90%) levels. LAF relish products were highly preferred by the consumers, with S. villosum controlled fermented relish (SvCFR) leading. All fermented relishes were stable at ambient (27°C) and refrigeration (4°C) temperatures after 6 months of storage. Generally, LAF is an effective method for ANS preservation, with improved nutritional quality and safety. LAF can therefore be recommended to small-scale farmers, processors, and households for ANS preservation. Ultimately, this method enhances the nutrition and sensory quality, safety, and livelihood.

Natural Bioactive Compounds in Organic and Conventional Fermented Food

Compared to conventional agriculture, organic farming is believed to provide a higher nutritional and health value in its products due to the elimination of harmful contaminants (pesticides, nitrates, heavy metals, etc.). Numerous studies have been conducted to show how the production system affects the quality of food in terms of the content of bioactive compounds. The aim of this study was to compare the content of some bioactive compounds (vitamin C, β-carotene, Ca content) and lactic acid bacteria (LAB) number and their bacteriocinogenic activity in organic and conventional fermented food. Although the results do not provide an unambiguous conclusion regarding the superiority of one production system over the other, the LAB number in organic pickled carrot juice, sauerkraut, yogurt, and kefir was higher than in their conventional counterparts. Their bacteriocinogenic potential against selected pathogens was also higher in most organic products. Organic vegetables contained significantly more vitamin C, and the calcium content in the organic yogurt was higher compared to the conventional version of the product. Relatively similar concentrations of ß-carotene for both production systems were found in carrot juice, while in organic pickled beet juice, there was five-fold less ß-carotene than in conventional juice.

Microbial Metabolic Pathways and the "Fermented Plant Foods-Human Health" Axis

Plant matrices are widely recognized as valuable sources of several health promoting compounds [...].

Changes in Phenols, Polysaccharides and Volatile Profiles of Noni (Morinda citrifolia L.) Juice during Fermentation

The change in phenols, polysaccharides and volatile profiles of noni juice from laboratory- and factory-scale fermentation was analyzed during a 63-day fermentation process. The phenol and polysaccharide contents and aroma characteristics clearly changed according to fermentation scale and time conditions. The flavonoid content in noni juice gradually increased with fermentation. Seventy-three volatile compounds were identified by solid-phase microextraction coupled with gas chromatography–mass spectrometry (SPME-GC-MS). Methyl hexanoate, 3-methyl-3-buten-1-ol, octanoic acid, hexanoic acid and 2-heptanone were found to be the main aroma components of fresh and fermented noni juice. A decrease in octanoic acid and hexanoic acid contents resulted in the less pungent aroma in noni juice from factory-scale fermentation. The results of principal component analysis of the electronic nose suggested that the difference in nitrogen oxide, alkanes, alcohols, and aromatic and sulfur compounds, contributed to the discrimination of noni juice from different fermentation times and scales.