Fermented food in the context of a healthy diet: how to produce novel functional foods?

Development, Analysis, and Sensory Evaluation of Improved Bread Fortified with a Plant-Based Fermented Food Product

In response to the demand for healthier foods in the current market, this study aimed to develop a new bread product using a fermented food product (FFP), a plant-based product composed of soya flour, alfalfa meal, barley sprouts, and viable microorganisms that showed beneficial effects in previous studies. White bread products prepared with three different substitution levels (5, 10, and 15%) of FFP were evaluated for physical characteristics (loaf peak height, length, width), color indices (lightness, redness/greenness, yellowness/blueness), quality properties (loaf mass, volume, specific volume), protein content, crumb digital image analysis, and sensory characteristics. The results revealed that FFP significantly affected all studied parameters, and in most cases, there was a dose-response effect. FFP supplementation affected the nutritional profile and increased the protein content (p < 0.001). The sensory test indicated that consumer acceptance of the studied sensory attributes differed significantly between groups, and bread with high levels of FFP (10 and 15% FFP) was generally more poorly rated than the control (0%) and 5% FFP for most of the variables studied. Despite this, all groups received acceptable scores (overall liking score ≥ 5) from consumers. The sensory analysis concluded that there is a possible niche in the market for these improved versions of bread products.

Effects of an Iranian traditional fermented food consumption on blood glucose, blood pressure, and lipid profile in type 2 diabetes: a randomized controlled clinical trial

BACKGROUND

Ash-Kardeh is one of the few fermented foods without a dairy base in Iran, which is traditionally prepared from cereals and plants in the presence of microorganisms (mainly lactic acid bacteria).

PURPOSE

This study aimed to assess the effects of Ash-Kardeh consumption on blood glucose, lipid profile, and blood pressure in type 2 diabetic patients.

METHODS

Forty-six patients with type 2 diabetes were studied in this randomized controlled clinical trial. Subjects were randomly allocated into intervention (n = 23) and control (n = 23) groups. Individuals of both groups received the usual treatment of diabetic patients, while those in the intervention group, in addition to the usual treatment, received 250 g of Ash-Kardeh daily for 6 weeks. Fasting blood glucose, blood pressure, and lipid profiles were measured before and after the intervention.

RESULTS

Compared to the control group, Ash-Kardeh consumption led to a significant decrease in fasting blood glucose (P = 0.003), total cholesterol (P = 0.025), triglyceride (P = 0.003), systolic (P < 0.001), and diastolic blood pressure (P = 0.014) in the intervention group. Also, a significant increase in the concentrations of high-density lipoprotein cholesterol (P = 0.048) was observed after Ash-Kardeh consumption.

CONCLUSION

It seems that Ash-Kardeh consumption could improve high blood glucose, lipid profile, and hypertension in type 2 diabetic patients but does not affect low-density lipoprotein cholesterol concentrations. This study was registered on 2019-09-15 in the Iranian Registry of Clinical Trials ( www.irct.ir ) with the code number IRCT20170202032367N3.

Fermented Foods, Health and the Gut Microbiome

Fermented foods have been a part of human diet for almost 10,000 years, and their level of diversity in the 21st century is substantial. The health benefits of fermented foods have been intensively investigated; identification of bioactive peptides and microbial metabolites in fermented foods that can positively affect human health has consolidated this interest. Each fermented food typically hosts a distinct population of microorganisms. Once ingested, nutrients and microorganisms from fermented foods may survive to interact with the gut microbiome, which can now be resolved at the species and strain level by metagenomics. Transient or long-term colonization of the gut by fermented food strains or impacts of fermented foods on indigenous gut microbes can therefore be determined. This review considers the primary food fermentation pathways and microorganisms involved, the potential health benefits, and the ability of these foodstuffs to impact the gut microbiome once ingested either through compounds produced during the fermentation process or through interactions with microorganisms from the fermented food that are capable of surviving in the gastro-intestinal transit. This review clearly shows that fermented foods can affect the gut microbiome in both the short and long term, and should be considered an important element of the human diet.

Anti-Oxidant and Anti-Inflammatory Substance Generated Newly in Paeoniae Radix Alba Extract Fermented with Plant-Derived Lactobacillus brevis 174A

Fermentation of medicinal herbs can be a significant technique to obtain bioactive compounds. Paeoniae Radix (PR) used in the present study is a well-known herbal medicine that exhibits anti-inflammatory and immunomodulatory activity. The aim of this study is to explore the possibility that a bioactive compound is newly generated in PR extract by fermentation with a plant-derived lactic acid bacteria Lactobacillus brevis 174A. We determined the anti-inflammatory activities in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophage cells. The PR extract fermented with Lactobacillus brevis 174A markedly increased the total phenolic content, decreased intracellular ROS levels, inhibited the release of nitric oxide (NO). It also suppressed inflammatory cytokines IL-6, TNF-ɑ, while simultaneously downregulating the gene expressions of iNOS, IL-6, TNF-ɑ, and IL-1β compared to the unfermented PR extract. Furthermore, the bioactive compound newly generated from the fermentation was identified as pyrogallol. It inhibits the inflammatory responses in a dose-dependent manner suggesting that fermentation of the herbal extract used as a medium together with the plant-derived lactic acid bacterial strain may be a practical strategy to produce medicines and supplements for healthcare.

Fermentation for future food systems: Precision fermentation can complement the scope and applications of traditional fermentation

Modern biotechnology holds great potential for expanding the scope of fermentation to create novel foods and improve the sustainability of food production.

FermFooDb: A database of bioactive peptides derived from fermented foods

Globally fermented foods are in demands due to their functional and nutritional benefits. These foods are sources of probiotic organisms and bioactive peptides, various amino acids, enzymes etc. that provides numerous health benefits. FermFooDb (https://webs.iiitd.edu.in/raghava/fermfoodb/) is a manually curated database of bioactive peptides derived from wide range of foods that maintain comprehensive information about peptides and process of fermentation. This database comprises of 2205 entries with following major fields, peptide sequence, Mass and IC50, food source, functional activity, fermentation conditions, starter culture, testing conditions of sequences in vitro or in vivo, type of model and method of analysis. The bioactive peptides in our database have wide range of therapeutic potentials that includes antihypertensive, ACE-inhibitory, antioxidant, antimicrobial, immunomodulatory and cholesterol lowering peptides. These bioactive peptides were derived from different types of fermented foods that include milk, cheese, yogurt, wheat and rice. Numerous, web-based tools have been integrated to retrieve data, peptide mapping of proteins, similarity search and multiple-sequence alignment. This database will be useful for the food industry and researchers to explore full therapeutic potential of fermented foods from specific cultures.

Cultivable non-starter lactobacilli from ripened Parmigiano Reggiano cheeses with different salt content and their potential to release anti-hypertensive peptides

The impact of salt and fat intake on human health drives the consumer's attention towards dairy food with reduced salt and fat contents. How changes in salt and fat content modulate dairy LAB population and the associated proteolytic activities have been poorly studied. Here, non-starter LAB populations from 12 Parmigiano Reggiano (PR) cheeses (12-month ripened), clustered in low salt and fat content (LL-PR) and high salt and fat content (HH-PR) groups, were investigated and identified at specie-level with molecular assays. Lactobacillus rhamnosus was dominant in HH-PR samples, whereas Lactobacillus paracasei in LL-PR samples. (GTG)₅ rep-PCR analysis discriminated 11 and 12 biotypes for L. rhamnosus and L. paracasei isolates, respectively. Screening for proteolytic activity identified L. rhamnosus strains more proteolytic than L. paracasei, and, within L. rhamnosus species, HH-PR strains were generally more proteolytic than LL-PR strains. Two L. rhamnosus representatives, namely strain 0503 from LL-PR and strain 2006 from HH-PR, were functionally characterized in cow milk fermentation assay. HH-PR strain 2006 overcame LL-PR strain 0503 in acidification performance, leading to a fermented milk with higher angiotensin I-converting enzyme inhibitory and antioxidant activities. L. rhamnosus 2006 was more prone to release VPP, while L. rhamnosus 0503 released higher amount of IPP. This study provides evidences that salt/fat content affects NSLAB cultivable fraction and the associated proteolytic ability resulting in a complex occurrence of bioactive peptides featuring health-promoting properties.

Fermentation for tailoring the technological and health related functionality of food products

Fermented foods are experiencing a resurgence due to the consumers' growing interest in foods that are natural and health promoting. Microbial fermentation is a biotechnological process which transforms food raw materials into palatable, nutritious and healthy food products. Fermentation imparts unique aroma, flavor and texture to food, improves digestibility, degrades anti-nutritional factors, toxins and allergens, converts phytochemicals such as polyphenols into more bioactive and bioavailable forms, and enriches the nutritional quality of food. Fermentation also modifies the physical functional properties of food materials, rendering them differentiated ingredients for use in formulated foods. The science of fermentation and the technological and health functionality of fermented foods is reviewed considering the growing interest worldwide in fermented foods and beverages and the huge potential of the technology for reducing food loss and improving nutritional food security.

Co-culture of Bacillus coagulans and Candida utilis efficiently treats Lactobacillus fermentation wastewater

Co-culture of Bacillus coagulans and Candida utilis was firstly investigated in the efficient treatment of Lactobacillus fermentation wastewater (LFW) containing total organic carbon (TOC) of 22.0 g/L and total nitrogen (TN) of 2.4 g/L. The utilization of lactic acid by C. utilis was responsible for the relief of feedback inhibition to promote the growth of B. coagulans. The removal ratio of TOC by B. coagulans and C. utilis was only 9.1% and 22.7%, respectively, which was improved to 49.0% by co-culture. The removal ratio of TN by B. coagulans and C. utilis was merely 6.3% and 12.5%, respectively, which was also promoted to 44.6% by co-culture. Both the high growth of B. coagulans and the efficient removal of TOC and TN from LFW was achieved with the co-culture, which is not previously reported and very important in the production of probiotics with the resource utilization of LFW.

Food-Derived Bioactive Peptides in Human Health: Challenges and Opportunities

Recent scientific evidence suggests that food proteins not only serve as nutrients, but can also modulate the body's physiological functions. These physiological functions are primarily regulated by some peptides that are encrypted in the native protein sequences. These bioactive peptides can exert health beneficial properties and thus are considered as a lead compound for the development of nutraceuticals or functional foods. In the past few decades, a wide range of food-derived bioactive peptide sequences have been identified, with multiple health beneficial activities. However, the commercial application of these bioactive peptides has been delayed because of the absence of appropriate and scalable production methods, proper exploration of the mechanisms of action, high gastro-intestinal digestibility, variable absorption rate, and the lack of well-designed clinical trials to provide the substantial evidence for potential health claims. This review article discusses the current techniques, challenges of the current bioactive peptide production techniques, the oral use and gastrointestinal bioavailability of these food-derived bioactive peptides, and the overall regulatory environment.

Whey Protein Isolate-Supplemented Beverage, Fermented by Lactobacillus casei BL23 and Propionibacterium freudenreichii 138, in the Prevention of Mucositis in Mice

Mucositis is a clinically important gastrointestinal inflammatory infirmity, generated by antineoplastic drugs cytotoxic effects. The inflammatory process caused by this disease frequently leads to derangements in the alimentary tract and great malaise for the patient. Novel strategies are necessary for its prevention or treatment, as currently available treatments of mucositis have several limitations in relieving its symptoms. In this context, several research groups have investigated the use of probiotic bacteria, and in particular dairy bacterial strains. Compelling evidences reveal that milk fermented by certain probiotic bacteria has the capacity to ameliorate intestinal inflammatory disorders. In addition, innovative probiotic delivery strategies, based on probiotics incorporation into protective matrices, such as whey proteins, were able to increase the therapeutic effect of probiotic strains by providing extra protection for bacteria against environmental stresses. Therefore, in this study, we evaluated the role of the whey protein isolate (WPI), when added to skim milk fermented by Lactobacillus casei BL23 (L. casei BL23) or by Propionibacterium freudenreichii CIRM-BIA138 (P. freudenreichii 138), as a protective matrix against in vitro stress challenges. In addition, we investigated the therapeutic effect of these fermented beverages in a murine model of mucositis induced by 5-Fluorouracil (5-FU). Our results demonstrated that milk supplementation with 30% (w/v) of WPI increases the survival rate of both strains when challenged with acid, bile salts, high temperature and cold storage stresses, compared to fermented skim milk without the addition of WPI. Moreover, treatment with the probiotic beverages prevented weight loss and intestinal damages in mice receiving 5-FU. We conclude that the presence of WPI maximizes the anti-inflammatory effects of L. casei BL23, but not for P. freudenreichii 138, suggesting that whey protein enhancement of probiotic activity might be strain-dependent.

Carrot Juice Fermentations as Man-Made Microbial Ecosystems Dominated by Lactic Acid Bacteria

Spontaneous vegetable fermentations, with their rich flavors and postulated health benefits, are regaining popularity. However, their microbiology is still poorly understood, therefore raising concerns about food safety. In addition, such spontaneous fermentations form interesting cases of man-made microbial ecosystems. Here, samples from 38 carrot juice fermentations were collected through a citizen science initiative, in addition to three laboratory fermentations. Culturing showed that Enterobacteriaceae were outcompeted by lactic acid bacteria (LAB) between 3 and 13 days of fermentation. Metabolite-target analysis showed that lactic acid and mannitol were highly produced, as well as the biogenic amine cadaverine. High-throughput 16S rRNA gene sequencing revealed that mainly species of Leuconostoc and Lactobacillus (as identified by 8 and 20 amplicon sequence variants [ASVs], respectively) mediated the fermentations in subsequent order. The analyses at the DNA level still detected a high number of Enterobacteriaceae, but their relative abundance was low when RNA-based sequencing was performed to detect presumptive metabolically active bacterial cells. In addition, this method greatly reduced host read contamination. Phylogenetic placement indicated a high LAB diversity, with ASVs from nine different phylogenetic groups of the Lactobacillus genus complex. However, fermentation experiments with isolates showed that only strains belonging to the most prevalent phylogenetic groups preserved the fermentation dynamics. The carrot juice fermentation thus forms a robust man-made microbial ecosystem suitable for studies on LAB diversity and niche specificity.

IMPORTANCE The usage of fermented food products by professional chefs is steadily growing worldwide. Meanwhile, this interest has also increased at the household level. However, many of these artisanal food products remain understudied. Here, an extensive microbial analysis was performed of spontaneous fermented carrot juices which are used as nonalcoholic alternatives for wine in a Belgian Michelin star restaurant. Samples were collected through an active citizen science approach with 38 participants, in addition to three laboratory fermentations. Identification of the main microbial players revealed that mainly species of Leuconostoc and Lactobacillus mediated the fermentations in subsequent order. In addition, a high diversity of lactic acid bacteria was found; however, fermentation experiments with isolates showed that only strains belonging to the most prevalent lactic acid bacteria preserved the fermentation dynamics. Finally, this study showed that the usage of RNA-based 16S rRNA amplicon sequencing greatly reduces host read contamination.

Oats as a matrix of choice for developing fermented functional beverages

Development of oat-based fermented beverages started in Europe in the past 30 years with the rise of the functional foods market. It is based on the increasing consumer demand for health drinks and value added foods and on the scientific insights on the nutrition composition of oats. The main health effects of oats are attributed to their high β-glucan content, which is proved to lower blood cholesterol and the intestinal absorption of glucose thus preventing diseases like cardiovascular injury, dyslipidemia, hypertension, inflammatory state and diabetes type 2. Another important role of β- glucan is its prebiotic function in the gastrointestinal tract, supporting the growth of beneficial microbial groups. The slowly digestible fraction of oat starch has a functional role as it moderates the glycaemic response. Oats are also a valuable source of highquality proteins, unsaturated lipids and antioxidants. In addition, oats are appropriate for people suffering from celiac disease because they do not contain gluten. Oat grain processing involves several steps, including thermal processes aiming to prevent oat products from rapid enzymatic deterioration and ensure storage stability. Oat drinks are formulated through processing oat with a liquid ingredient. Further, this matrix is inoculated with lactic acid bacteria to produce a fermented beverage. In some, drinks, probiotic lactic acid bacteria were used to increase product functional value. Thus, the ancient concept of cereal-based fermented foods is implemented into development of new functional oat-based fermented beverages and several products are already marketed in Europe as healthy, fast and convenient supplementary foods.

Harnessing the Power of Microbiome Assessment Tools as Part of Neuroprotective Nutrition and Lifestyle Medicine Interventions

An extensive body of evidence documents the importance of the gut microbiome both in health and in a variety of human diseases. Cell and animal studies describing this relationship abound, whilst clinical studies exploring the associations between changes in gut microbiota and the corresponding metabolites with neurodegeneration in the human brain have only begun to emerge more recently. Further, the findings of such studies are often difficult to translate into simple clinical applications that result in measurable health outcomes. The purpose of this paper is to appraise the literature on a select set of faecal biomarkers from a clinician’s perspective. This practical review aims to examine key physiological processes that influence both gastrointestinal, as well as brain health, and to discuss how tools such as the characterisation of commensal bacteria, the identification of potential opportunistic, pathogenic and parasitic organisms and the quantification of gut microbiome biomarkers and metabolites can help inform clinical decisions of nutrition and lifestyle medicine practitioners.

Lactobacillus plantarum with broad antifungal activity: A promising approach to increase safety and shelf-life of cereal-based products

Cereal-based fermented products are worldwide diffused staple food resources and cereal-based beverages represent a promising innovative field in the food market. Contamination and development of spoilage filamentous fungi can result in loss of cereal-based food products and it is a critical safety concern due to their potential ability to produce mycotoxins. Lactic Acid Bacteria (LAB) have been proposed as green strategy for the control of the moulds in the food industry due to their ability to produce antifungal metabolites. In this work, eighty-eight Lactobacillus plantarum strains were screened for their antifungal activity against Aspergillus niger, Aspergillus flavus, Fusarium culmorum, Penicillium roqueforti, Penicillium expansum, Penicillium chrysogenum, and Cladosporium spp. The overlayed method was used for a preliminary discrimination of the strains as no, mild and strong inhibitors. L. plantarum isolates that displayed broad antifungal spectrum activity were further screened based on the antifungal properties of their cell-free supernatant (CFS). CFSs from L. plantarum UFG 108 and L. plantarum UFG 121, in reason of their antifungal potential, were characterized and analyzed by HPLC. Results indicated that lactic acid was produced at high concentration during the growth phase, suggesting that this metabolic aptitude, associated with the low pH, contributed to explain the highlighted antifungal phenotype. Production of phenyllactic acid was also observed. Finally, a new oat-based beverage was obtained by fermentation with the strongest antifungal strain L. plantarum UFG 121. This product was submitted or not to a thermal stabilization and artificially contaminated with F. culmorum. Samples containing L. plantarum UFG 121 showed the best biopreservative effects, since that no differences were observed in terms of some qualitative features between not or contaminated samples with F. culmorum. Here we demonstrate, for the first time, the suitability of LAB strains for the fermentation and antifungal biopreservation of oat-based products.

Maintaining gut ecosystems for health: Are transitory food bugs stowaways or part of the crew?

Do food ecosystems feed gut ecosystems? And if so… fuel the immune system? Recent developments in metagenomics have provided researchers tools to open the "black box" of microbiome science. These novel technologies have enabled the establishment of correlations between dysbiotic microbial communities and many diseases. The complex interaction of the commensal microbiota with the immune system is a topic of substantial interest due to its relevance to health. The human gastrointestinal tract is composed of an immense number of resident and transient microorganisms. Both may play a direct and vital role in the maintenance of human health and well-being. An understanding of the interactions and mechanisms through which commensal and food-derived microbes shape host immunity and metabolism may yield new insights into the pathogenesis of many immune-mediated diseases. Consequently, by manipulating the contribution of food microbiota to the functionality of the gut ecosystem, there is great hope for development of new prophylactic and therapeutic interventions. This paper presents some insights and comments on the possible impact of exogenous fermented food microbes on the gut homeostasis. We shed light on the similar features shared by both fermented food microbes and probiotics. In particular, the key role of microbial strains as part of food ecosystems for health and diseases is discussed through the prism of fermented dairy products and gut inflammation.