Process Optimization for Development of a Novel Water Kefir Drink with High Antioxidant Activity and Potential Probiotic Properties from Russian Olive Fruit (Elaeagnus angustifolia)

Probiotic fermentation environment control under intelligent data monitoring

Probiotic fermentation studies are vital in many areas, particularly when it comes to feeding applications. This work examines probiotic fermentation in oil tea crops. The assessment of tea saponin-degrading bacteria and optimization of fermentation conditions using fermented oil tea cake under natural conditions, screening out six strains with strong ability to degrade tea saponin; selection of the best tea saponin degradation strain L.2 and recognition of its morphological features and ITS sequence to obtain L.2 strain is Aspergillus Niger. Oil tea is rich in tea saponin. Aspergillus Niger degraded tea saponins in oil teacakes at a rate of 93.96 % under the ideal conditions of 31.3 oC, 103.5 h, and 4.57 mL of initial acid addition. This has been accomplished via solid-state fermentation of L.2 using single factor studies and surface response optimization experiments. Moreover, Aspergillus Niger degraded tea saponins in oil tea cakes at a rate of 93.96% at the ideal circumstances of 31.3 C, 103.5 h, and 4.57 mL of initial acid addition.

Challenges in water kefir production and limitations in human consumption: A comprehensive review of current knowledge

Water kefir is a convenient dairy-free alternative to dairy-based fermented beverages. It is prepared by fermenting a sucrose solution with fresh and dried fruits using water kefir grains, and demineralized whey can be used in water kefir production. This review describes current knowledge on water kefir production and its health effects. The main aims of this paper are to focus on the microbial composition, potential health-promoting properties, limitations in human consumption, and challenges in the production of water kefir. Water kefir grains and substrates, including brown sugar, dried and fresh fruits, vegetables, and molasses, used in the production influence the fermentation characteristics and composition of water kefir. Lactic acid bacteria, acetic acid bacteria, and yeasts are the microorganisms involved in the fermentation process. Lactobacillus species are the most common microorganisms found in water kefir. Water kefir contains various bioactive compounds that have potential health benefits. Water kefir may inhibit the growth of certain pathogenic microorganisms and food spoilage bacteria, resulting in various health-promoting properties, including immunomodulatory, antihypertensive, anti-inflammatory, anti-ulcerogenic, antiobesity, hypolipidemic, and hepatoprotective activities.

Integrated Membrane Process in Organic Media: Combining Organic Solvent Ultrafiltration, Nanofiltration, and Reverse Osmosis to Purify and Concentrate the Phenolic Compounds from Wet Olive Pomace

Phenolic compounds from a hydroalcoholic extract of wet olive pomace were purified and concentrated by an integrated membrane process in organic media. First, UF010104 (Solsep BV) and UP005 (Microdyn Nadir) membranes were tested to be implemented in the ultrafiltration stage, with the aim of purifying the extract and obtaining a permeate enriched in phenolic compounds. Despite the high flux observed with the UF010104 membrane (20.4 ± 0.7 L·h-1·m-2, at 2 bar), the UP005 membrane was selected because of a more suitable selectivity. Even though some secoiridoids were rejected, the permeate stream obtained with this membrane contained high concentrations of valuable simple phenols and phenolic acids, whereas sugars and macromolecules were retained. Then, the ultrafiltration permeate was subjected to a nanofiltration step employing an NF270 membrane (DuPont) for a further purification and fractionation of the phenolic compounds. The permeate flux was 50.2 ± 0.2 L·h-1·m-2, working at 15 bar. Hydroxytyrosol and some phenolic acids (such as vanillic acid, caffeic acid, and ferulic acid) were recovered in the permeate, which was later concentrated by reverse osmosis employing an NF90 membrane. The permeate flux obtained with this membrane was 15.3 ± 0.3 L·h-1·m-2. The concentrated phenolic mixture that was obtained may have important applications as a powerful antioxidant and for the prevention of diabetes and neurodegenerative diseases.

Physical, chemical, and sensory properties of water kefir produced from Aronia melanocarpa juice and pomace

Water kefir is widely consumed all over the world due to its potential health benefits. The aim of this current study was to compare non-fermented juice and fermented beverage of water kefir produced from Aronia melanocarpa juice and pomace in terms of chemical, physical and sensory quality as well as valorisation of pomace in the production of water kefir. When compared to water kefir made with aronia juice, less reduction in total phenolic content (TPC), total flavonoid content (TFC) and total anthocyanin content (TAC) was observed in samples made with aronia pomace during the fermentation process. Similarly, greater antioxidant activity was demonstrated in water kefir made with aronia pomace than juice. Based on sensory evaluation, no difference was found in overall acceptability, taste, aroma/odor, and turbidity of water kefir made with aronia pomace before and after fermentation. Results indicated that aronia pomace has potential in water kefir production.

Innovative beverage creation through symbiotic microbial communities inspired by traditional fermented beverages: current status, challenges and future directions

Fermented beverages (FBs) are facing challenges in functional performance and flavor complexity, necessitating the development of new multi-functional options. Traditional fermented beverages (TFBs), both alcoholic and nonalcoholic, have gained increased attention for their health-promoting effects during the COVID-19 pandemic. This review summarized the primary commercially available probiotics of FBs, along with the limitations of single and mixed probiotic FBs. It also examined the recent research progress on TFBs, emphasizing the typical microbial communities (MC) of TFBs, and TFBs made from crops (grains, vegetables, fruits, etc.) worldwide and their associated functions and health benefits. Furthermore, the construction, technical bottlenecks of the synthetic MC involved in developing innovative FBs were presented, and the promising perspective of FBs was described. Drawing inspiration from the MC of TFBs, developing of stable and multifunctional FBs using synthetic MC holds great promise for beverage industry. However, synthetic MC suffers from structural instability and poorly acknowledged interaction mechanisms, resulting in disappointing results in FBs. Future researches should prioritize creating synthetic MC fermentation that closely resemble natural fermentation, tailored to meet the needs of different consumers. Creating personalized FBs with high-tech intelligence is vital in attracting potential consumers and developing novel beverages for the future.

Optimization of Ultrasonic-Assisted Extraction of Active Components and Antioxidant Activity from Polygala tenuifolia: A Comparative Study of the Response Surface Methodology and Least Squares Support Vector Machine

Dried roots of Polygala tenuifolia (YuanZhi in Chinese) are widely used in Chinese herbal medicine. These components in YuanZhi have significant anti-oxidation properties owing to high levels of 3,6'-disinapoylsucrose (DISS) and Polygalaxanthone III (PolyIII). In order to efficiently extract natural medicines, response surface methodology (RSM) and least squares support vector machine (LSSVM) were used for the modeling and optimization of ultrasound-assisted extraction of DISS and PolyIII together to determine the antioxidant activity of the extracts obtained from YuanZhi. For the optimal combination of the comprehensive yield of DISS and PolyIII (Y), the Box-Behnken design (BBD) was used to improve extraction time (X₁), extraction temperature (X₂), liquid-solid ratio (X₃), and ethanol concentration (X₄). The optimal process parameters were determined to be as follows: extraction time, 93 min; liquid-solid ratio, 40 mL/g; extraction temperature, 48 °C; and ethanol concentration, 67%. With these conditions, the predictive optimal combination comprehensive evaluation value is 13.0217. It was clear that the LS-SVM model had higher accuracy in predictive and optimization capabilities, with higher antioxidant activity and lower relative deviations values, than did RSM. Hence, the LS-SVM model proved to be more effective for the analysis and improvement of the extraction process.

Water kefir: Factors affecting grain growth and health-promoting properties of the fermented beverage

Nowadays, the interest in the consumption of healthy foods has increased as well as the homemade preparation of artisanal fermented product. Water kefir is an ancient drink of uncertain origin, which has been passed down from generation to generation and is currently consumed practically all over the world. Considering the recent and extensive updates published on sugary kefir, this work aims to shed light on the scientific works that have been published so far in relation to this complex ecosystem. We focused our review evaluating the factors that affect the beverage microbial and chemical composition that are responsible for the health attribute of water kefir as well as the grain growth. The microbial ecosystem that constitutes the grains and the fermented consumed beverage can vary according to the fermentation conditions (time and temperature) and especially with the use of different substrates (source of sugars, additives as fruits and molasses). In this sense, the populations of microorganisms in the beverage as well as the metabolites that they produce varies and in consequence their health properties. Otherwise, the knowledge of the variables affecting grain growth are also discussed for its relevance in maintenance of the starter biomass as well as the use of dextran for technological application.

Encapsulation of Russian Olive Water Kefir as an Innovative Functional Drink with High Antioxidant Activity

Processing of Russian olive water kefir (RWK), as a fermented functional drink made with Russian olive juice and water kefir grains with high antioxidant activity, into powder is crucial for improving its stability for the commercialization of this product. For the first time, this study aimed to encapsulate water kefir microorganisms and bioactive compounds in RWK using carrier materials to develop a synbiotic functional powder using spray drying as an encapsulation method. The goal was maximizing antioxidant activity, product yield, and survival rate of water kefir microorganisms in the produced Russian olive water kefir powder. The optimal spray drying conditions were observed to be at an inlet air temperature of 120ºC, 35 % feed flow rate, and 7 % concentration of drying aid. The effects of spray drying conditions on the quality of microcapsules were assessed and modeled, and the validity of the model was verified. Also, the spray-dried powder's physicochemical properties were assessed and showed promising microbial and physicochemical characteristics compared with the freeze-dried powder.