Development of Blueberry and Carrot Juice Blend Fermented by Lactobacillus reuteri LR92

Exploring fermentation with lactic acid bacteria as a pretreatment for enhancing antioxidant potential in broccoli stem powders

Fruit and vegetable industries face a major environmental challenge with food loss and waste. Broccoli stems, comprising 38% of the plant's total weight, are usually discarded by the industry producing fourth-range and ready-to-use products, despite being rich in antioxidants, vitamins, fiber, carotenoids, phenolic compounds, and glucosinolates. Addressing the challenge of reducing waste in this sector includes the production of stable and nutrient-concentrated powders, which can be consumed directly or used as ingredients in functional food formulation. This study investigated fermentation with lactic acid bacteria (Limosilactobacillus reuteri, Lactiplantibacillus plantarum, and Lactobacillus salivarius) as a pretreatment for enhancing antioxidant and probiotic potential in broccoli stem powders. Results showed maximum counts 24 h after inoculation, and no effect of the previous disruption intensity on microbial growth was observed. Fermenting broccoli stems for 24 h with the three microbial strains led to a significant increase in total phenols and flavonoids but to a general reduction in the samples' capacity to scavenge DPPH and ABTS free radicals. Overall, ground broccoli stems exhibited the most favorable antioxidant properties following the 24 h fermentation step. The subsequent freeze-drying and final grinding had minimal impact on the microbial population but significantly enhanced the extractability of the antioxidant compounds. This study offers a valuable reference for researchers and stakeholders exploring the development of new products and innovations from vegetable waste.

The consequences of fermentation metabolism on the qualitative qualities and biological activity of fermented fruit and vegetable juices

Fermentation of fruit and vegetable juices with probiotics is a novel nutritional approach with potential health benefits. Lactic acid fermentation-based biotransformation results in changes in the profile and nature of bioactive compounds and improves the organoleptic properties, shelf life and bioavailability of vitamins and minerals in the fermented juices. This process has been shown to enrich the phenolic profile and bioactivity components of the juices, resulting in a new type of functional food with improved health benefits. Fruits and vegetables are the ideal substrate for microbial growth, and fruit and vegetable juice will produce rich nutrients and a variety of functional activities after fermentation, so that the high-quality utilization of fruits and vegetables is realized, and the future fermented fruit and vegetable juice products have a wide application market. This paper explores the typical fermentation methods for fruit and vegetable juices, investigates the bioactive components, functional activities, and the influence of fermentation on enhancing the quality of fruit and vegetable juices. The insights derived from this study carry significant implications for guiding the development of fermented fruit and vegetable juice industry.

The Biochemical, Microbiological, Antioxidant and Sensory Characterization of Fermented Skimmed Milk Drinks Supplemented with Probiotics Lacticaseibacillus casei and Lacticaseibacillus rhamnosus

A variety of foods fermented with lactic acid bacteria (LAB) serve as dietary staples in many countries. The incorporation of health-promoting probiotics into fermented milk products can have profound effects on human health. Considering the health benefits of Yakult, the current study was undertaken to develop an enriched Yakult-like fermented skimmed milk drink by the addition of two probiotic strains, namely Lacticaseibacillus casei (Lc) and Lacticaseibacillus rhamnosus (Lr). The prepared drinks were compared in terms of various parameters, including their physicochemical properties, proximate chemical composition, mineral estimation, microbial viable count, antioxidant activity, and sensory evaluation. Each strain was employed at five different concentrations, including 1% (T1), 1.5% (T2), 2% (T3), 2.5% (T4), and 3% (T5). The prepared Yakult samples were stored at 4 °C and analyzed on days 0, 7, 14, 21, and 28 to evaluate biochemical changes. The findings revealed that the concentration of the starter culture had a significant (p ≤ 0.05) impact on the pH value and moisture and protein contents, but had no marked impact on the fat or ash content of the developed product. With the Lc strain, Yakult's moisture content ranged from 84.25 ± 0.09 to 85.65 ± 0.13%, whereas with the Lr strain, it was from 84.24 ± 0.08 to 88.75 ± 0.13%. Protein levels reached their highest values with T5 (3% concentration). The acidity of all treatments increased significantly due to fermentation and, subsequently, pH showed a downward trend (p ≤ 0.05). The total soluble solids (TSS) content decreased during storage with Lc as compared to Lr, but the presence of carbohydrates had no appreciable impact. The drink with Lc exhibited a more uniform texture and smaller pore size than Yakult with Lr. Except for the iron values, which showed an increasing trend, the contents of other minerals decreased in increasing order of the added probiotic concentration used: 1% (T1), 1.5% (T2), 2% (T3), 2.5% (T4), and 3% (T5). The highest lactobacilli viable count of 8.69 ± 0.43 colony-forming units (CFU)/mL was observed with the T1 Lr-containing drink at the end of the storage period. Regarding the storage stability of the drink, the highest value for DPPH (88.75 ± 0.13%) was found with the T1 Lc drink on day 15, while the highest values for FRAP (4.86 ± 2.80 mmol Fe2+/L), TPC (5.97 ± 0.29 mg GAE/mL), and TFC (3.59 ± 0.17 mg GAE/mL) were found with the T5 Lr drink on day 28 of storage. However, the maximum value for ABTS (3.59 ± 0.17%) was noted with the T5 Lr drink on the first day of storage. The results of this study prove that Lc and Lr can be used in dairy-based fermented products and stored at refrigerated temperatures.

Exploring the antioxidant potential of fermented turmeric pulp: effect of extraction methods and microencapsulation

Curcumin is one of the major constituents of turmeric which possess multifarious therapeutic properties. However, owing of its limited solubility in water its bioavailability is poor. Thus, attempts have been made to increase the solubility of curcumin by fermenting turmeric followed by extraction and encapsulation. Lactobacillus fermentum was used for the fermentation of raw turmeric pulp. The influence of Lactobacillus fermentation and different extraction methods (conventional solvent extraction (CSE), ultrasound (UAE) and microwave-assisted extraction (MAE)) on total phenolic content (TPC), flavonoid content, antioxidant activity and curcumin content were analyzed. Further, to increase the stability of extract, different concentrations of maltodextrin were used to microencapsulate the curcumin extract. The results showed that, Lactobacillus fermentation increased the TPC and antioxidant activity from 5.59 ± 0.20 to 6.27 ± 0.28 mg GAE/g and 67.49 ± 1.51 to 79.00 ± 2.20%, respectively. MAE showed highest TPC (7.88 ± 0.08 mg GAE/g), antioxidant activity (94 ± 1.57%) and curcumin content (0.866 ± 0.05 mg/g) followed by UAE and CSE. Maximum yield of curcumin extract was observed in MAE, UAE and CSE as 59.93, 47.09 and 29.44% respectively, higher than non-fermented turmeric pulp. Maltodextrin percentage showed a significant influence on bio-functional properties of encapsulated powder. However, 20% maltodextrin exhibited better bio-functional properties as compared to other concentrations.

Characterization of a fermented coconut milk product with and without strawberry pulp

The development of plant-based milks for use as functional foods is relatively new and challenging. The objective of this work was to develop and characterize two coconut milk products fermented by Lactobacillus reuteri LR 92. The best proportion of gums to promote greater viscosity and absence of syneresis of the beverage was 0.15% xanthan gum (w/v) and 0.05% guar gum (w/v). Two products were formulated: fermented coconut milk (FC) and fermented coconut milk with strawberry pulp (FCS). After gastrointestinal simulation, a high survival rate of L. reuteri was found for the products, with 81.63 ± 0.58% for FC and 74.17 ± 1.65% for FCS. In the hedonic acceptance sensory test (total 9 points), the products obtained global scores above 7.5. In the attitude scale test (total 7 points), 5.10 ± 1.28 for FC and 5.48 ± 1.30 for FCS. Among the fatty acids detected, the products had a higher percentage of lauric acid, with values ranging from 37.89 ± 0.89% to 44.45 ± 3.16%. The FC and FCS products showed promising results, indicating that fermented coconut milk beverages are suitable for the development of new functional products with high acceptability by the consumer.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13197-021-05303-1.

Cherries and Blueberries-Based Beverages: Functional Foods with Antidiabetic and Immune Booster Properties

Nowadays, it is largely accepted that the daily intake of fruits, vegetables, herbal products and derivatives is an added value in promoting human health, given their capacity to counteract oxidative stress markers and suppress uncontrolled pro-inflammatory responses. Given that, natural-based products seem to be a promising strategy to attenuate, or even mitigate, the development of chronic diseases, such as diabetes, and to boost the immune system. Among fruits, cherries and blueberries are nutrient-dense fruits that have been a target of many studies and interest given their richness in phenolic compounds and notable biological potential. In fact, research has already demonstrated that these fruits can be considered functional foods, and hence, their use in functional beverages, whose popularity is increasing worldwide, is not surprising and seem to be a promising and useful strategy. Therefore, the present review reinforces the idea that cherries and blueberries can be incorporated into new pharmaceutical products, smart foods, functional beverages, and nutraceuticals and be effective in preventing and/or treating diseases mediated by inflammatory mediators, reactive species, and free radicals.

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.

Development of Anti-inflammatory Probiotic Limosilactobacillus reuteri EFEL6901 as Kimchi Starter: in vitro and In vivo Evidence

The use of probiotic starters can improve the sensory and health-promoting properties of fermented foods. In this study, we developed an anti-inflammatory probiotic starter, Limosilactobacillus reuteri EFEL6901, for use in kimchi fermentation. The EFEL6901 strain was safe for use in foods and was stable under human gastrointestinal conditions. In in vitro experiments, EFEL6901 cells adhered well to colonic epithelial cells and decreased nitric oxide production in lipopolysaccharide-induced macrophages. In in vivo experiments, oral administration of EFEL6901 to DSS-induced colitis mice models significantly alleviated the observed colitis symptoms, prevented body weight loss, lowered the disease activity index score, and prevented colon length shortening. Analysis of these results indicated that EFEL6901 played a probiotic role by preventing the overproduction of pro-inflammatory cytokines, improving gut barrier function, and up-regulating the concentrations of short-chain fatty acids. In addition, EFEL6901 made a fast growth in a simulated kimchi juice and it synthesized similar amounts of metabolites in nabak-kimchi comparable to a commercial kimchi. This study demonstrates that EFEL6901 can be used as a suitable kimchi starter to promote gut health and product quality.

High-Pressure Homogenization and Biocontrol Agent as Innovative Approaches Increase Shelf Life and Functionality of Carrot Juice

Recently, application of high-pressure homogenization (HPH) treatments has been widely studied to improve shelf life and rheological and functional properties of vegetable and fruit juices. Another approach that has drawn the attention of researchers is the use of biocontrol cultures. Nevertheless, no data on their possible combined effect on fruit juices shelf life and functionality have been published yet. In this work, the microbial, organoleptic, and technological stability of extremely perishable carrot juice and its functionality were monitored for 12 and 7 days (stored at 4 and 10 °C, respectively) upon HPH treatment alone or in combination with a fermentation step using the biocontrol agent L. lactis LBG2. HPH treatment at 150 MPa for three passes followed by fermentation with L. lactis LBG2 extended the microbiological shelf life of the products of at least three and seven days when stored at 10 °C and 4 °C, respectively, compared to untreated or only HPH-treated samples. Moreover, the combined treatments determined a higher stability of pH and color values, and a better retention of β-carotene and lutein throughout the shelf-life period when compared to unfermented samples. Eventually, use of combined HPH and LBG2 resulted in the production of compounds having positive sensory impact on carrot juice.

Effects of Cabbage-Apple Juice Fermented by Lactobacillus plantarum EM on Lipid Profile Improvement and Obesity Amelioration in Rats

This study aimed to investigate the potential of cabbage-apple juice, fermented by Lactobacillus plantarum EM isolated from kimchi, to protect against obesity and dyslipidemia that are induced by a high-fat diet in a rat model. Male rats were fed a modified AIN-93M high-fat diet (HFD), the same diet supplemented with non-fermented cabbage-apple juice, or the same diet supplemented with fermented cabbage-apple juice for eight weeks. In the HFD-fermented cabbage- apple juice administered groups the following parameters decreased: body weight, liver and white fat pad weights, serum triglyceride (TG), total cholesterol (TC), LDL-cholesterol, insulin, glucose and leptin levels, TG levels, while HDL-C and adiponectin levels in serum increased as compared with the HFD group. The HFD-fed rats that were supplemented with fermented cabbage-apple juice exhibited significantly lower fatty acid synthase (FAS), acetyl-CoA carboxylase (ACC), and malic enzyme gene expression levels when compared to the exclusively HFD-fed rats. The anti-obesity and hypolipidemic effects were marginally greater in the fermented juice administered group than in the non-fermented juice administered group. These results suggest that cabbage-apple juice-especially fermented cabbage-apple juice-might have beneficial effects on lipid metabolism dysfunction and obesity-related abnormalities. However, further studies are necessary for analyzing the biochemical regulatory mechanisms of fermented juice for obesity amelioration and lipid metabolic homeostasis.

In Vitro Modulation of Fecal Microflora Growth Using Fermented “Pisang Mas” Banana and Red Guava Juices

Probiotic drink like yoghurt from dairy milk is one of the most popular functional food. However, some people are not able to consume dairy milk due to lactose intolerance. Thus, a substitute substrate such as fruit juice, is needed. It refers to prebiotic compounds that are found in some of fruits like banana and guava. The aim of this research was to determine the effect of fermented banana and guava juices on the viability of fecal microflora. The juices were made from banana or red guava fermented by Lactobacillus casei (15% v/v). In vitro test was conducted using indigenous human fecal bacteria (1% w/v). The viability of enteropathogens, lactic acid bacteria (LAB), and total microbes was determined by enumeration as well as the prebiotic index of the fermented juices. The in vitro test results showed that both fermented juices could elevate the total microbes and LAB as compared to control sample. The viability of the total microbes and LAB increased by 2.16 log CFU/mL and 2.90 log CFU/mL for fermented banana juice (FBJ), respectively. The same trend was also observed in fermented guava juice (FGJ) with an increase by 1.92 log CFU/mL for total microbes and 2.99 log CFU/mL for LAB. Interestingly, both fermented juice could decrease the population of most enteropathogens compared to control sample. FBJ could decrease the population of E. coli, Klebsiella sp. and Salmonella as low as 3.78, 3.32, and 1.37 log CFU/mL respectively. Meanwhile, FGJ could drop the number of E. coli (1.44 log CFU/mL), and Klebsiella sp. (1.29 log CFU/mL). Moreover, the prebiotic index for FBJ and FGJ were 2.57 and 2.16. In conclusion, both FBJ and FGJ were potential substrate for probiotic drink and had good effect for fecal microflora health.

Criterios y estrategias tecnológicas para la incorporación y supervivencia de probióticos en frutas, cereales y sus derivados

Los alimentos a los que se les añaden probióticos (bacterias benéficas) constituyen uno de los sectores más importantes de los alimentos funcionales. Los productos lácteos son los principales vehículos para estas bacterias que producen un efecto benéfico a la salud, cuando se consumen vivas y en cantidades suficientes para adherirse al colon. Sin embargo, cada día crece el interés por desarrollar alimentos no lácteos como vehículo para probióticos. Los productos de origen vegetal son una buena alternativa para estas innovaciones. Tienen la ventaja de que son muy aceptados y accesibles para la población. Adicionalmente, representan una alternativa de consumo para poblaciones con dietas restringidas. Sin embargo, la incorporación de probióticos a estos productos requiere considerar varios criterios y vencer retos tecnológicos con la finalidad de conservarlos funcionalmente activos.

Volatile Molecule Profiles and Anti-Listeria monocytogenes Activity of Nisin Producers Lactococcus lactis Strains in Vegetable Drinks

This work aimed to evaluate the potential of 15 nisin producing Lactococcus lactis strains, isolated from dairy products, for the fermentation of soymilk and carrot juice. In particular, the acidification and the production of nisin in the food matrices were recorded. Moreover, three strains (LBG2, FBG1P, and 3LC39), that showed the most promising results were further scrutinized for their anti-Listeria monocytogenes activity and volatile molecules profile during fermentation of soymilk and carrot juice. Lactococcus lactis strains LBG2, FBG1P, and 3LC39 resulted the most interesting ones, showing rapid growth and acidification on both food matrices. The higher amounts of nisin were detected in soymilk samples fermented by the strain LBG2 after 24 and 48 h (26.4 mg/L). Furthermore, the rapid acidification combined with the production of nisin resulted in a strong anti-Listeria activity, reducing the pathogen loads below the detection limit, in carrot juice samples fermented by the strains LBG2 and FBG1P and in soymilk by the strain LBG2. The fermentation increased the presence of volatile molecules such as aldehydes and ketones with a positive impact on the organoleptic profile of both the fermented products. These results highlighted the interesting potential of three nisin producing L. lactis strains for the production of fermented carrot juice and soymilk. In fact, the fermentation by lactic acid bacteria, combined or not with other mild technologies, represents a good strategy for the microbiological stabilization of these products. Furthermore, the increase of molecules with a positive sensory impact, such as aldehydes and ketones, in the fermented products suggests a possible improvement of their organoleptic characteristics.

Coconut milk beverage fermented by Lactobacillus reuteri: optimization process and stability during refrigerated storage

This study aimed to establish the optimal conditions of temperature (31-43 °C) and coconut pulp concentration in water 1:3-1:9 (w/v) for the growth of Lactobacillus reuteri LR 92 or DSM 17938 in coconut milk beverage, using a central composite face centered design. The optimized conditions were used for analysis of the viability during the fermentation process, pH, production of sugars and organic acids by High Performance Liquid Chromatography (HPLC) and reuterin production. Coconut milk provided adequate substrate for L. reuteri growth without supplementation. The optimal parameters for L. reuteri viability were: concentration 1:3 (w/v) and 37 °C for LR 92 and concentration 1:3 (w/v) and 34 °C for DSM 17938. Chemical analysis showed that the naturally occurring sucrose in the matrix (ca. 4.4 g/L) was used for cell multiplication and the strains differed in the production and content of organic acids. After fermentation until pH 4.5 ± 0.1, the samples were stored at 4 °C for 30 days and the final cell viability in coconut milk was 7.55 ± 0.07 log CFU/mL for L. reuteri LR 92 and 8.57 ± 0.09 log CFU/mL for DSM 17938. It was detected 0.15 ± 0.03 mM and 0.14 ± 0.04 mM of reuterin produced by DSM 17938 and LR 92, respectively. L. reuteri DSM 17938 presented a great decrease of pH and post acidification after storage. The LR 92 strain showed low post acidification. These results showed that coconut milk provides adequate matrix for the development of new fermented functional beverages.