Development of natural pigments microencapsulated in waste yeast Saccharomyces cerevisiae using spray drying technology and their application in yogurt

Sonoprocessing enhances the stabilization of fisetin by encapsulation in Saccharomyces cerevisiae cells

The objective of this study was to investigate for the first time the role of S. cerevisiae natural barriers and endogenous cytoplasmatic bodies on the stabilization of fisetin encapsulated via sonoprocessing coupled to freeze-drying (FD) or spray drying (SD). Both protocols of encapsulation improved the resistance of fisetin against thermal treatments (between 60 and 150 °C) and photochemical-induced deterioration (light exposition for 60 days) compared to non-encapsulated fisetin (antioxidant activity retention of approximately 55% and 90%, respectively). When stored under constant relative humidity (from 32.8 to 90%) for 60 days, yeast carriers improved the half-life time of fisetin by up to 4-fold. Spray dried particles were smaller (4.9 μm) and showed higher fisetin release after simulated gastrointestinal digestion (55.7%) when compared to FD. Freeze-dried particles, in turn, tended to agglomerate more than SD (zeta potential -19.7 mV), resulting in reduced loading features (6.3 mg/g) and less efficient protection of fisetin to heat, photo, and moisture-induced deterioration. Overall, spray-dried sonoprocessed fisetin capsules are an efficient way to preserve fisetin against harsh conditions. Altogether, this report shows that sonoprocessing coupled to drying is an efficient, creative, and straightforward route to protect and deliver lipophilic fisetin using yeast capsules for food applications.

Enhancing the functionality of plant-based Yogurt: Integration of lycopene through dual-stage fermentation of soymilk

Well-defined compositional assemblies of plant-based yogurt are of fast-growing awareness for world population concerning environmental sustainability, economic burdens and health risks. Soybean is an attractive candidate for plant yogurt, suffering from poor flavor, limited nutrition, and undesired allergens to offer healthy-functional segments. Herein, we deciphered a novel lycopene-soy yogurt by efficient two-stage fermentation of engineered B. subtilis and LAB. The fortified sogurt was ensured with redundant lycopene of 22.67 ± 2.95 mg/g DCW by engineered B. subtilis and enriched soy isoflavone from synergistic effects of engineered B. subtilis and LAB, possessing strong antioxidant capacity for upgrading functionality. Moreover, the desired pH, accelerated protein hydrolysis, enhanced amino acid availability, and expected sensory attributes cooperatively conferred lycopene-soy yogurt as healthy functional food. High potential is firstly ascribed to sequential dual culture of engineered B. subtilis and LAB in lycopene-soy yogurt, in which flavorful, hypoallergenic and antioxidative ingredients enabled functionalities for plant-based yogurt.

Augmenting Functional and Sensorial Quality Attributes of Kefir through Fortification with Encapsulated Blackberry Juice

Kefir is a fermented dairy product claimed to confer many health-promoting effects, but its acidic taste is not appealing to some consumers. Therefore, the aim of this study was to enhance the functional and sensorial quality attributes of kefir through fortification with encapsulated blackberry juice (EBJ). The blackberry juice was successfully encapsulated via freeze-drying using lentil protein isolate (LPI) as the carrier. The encapsulated blackberry juice showed good physicochemical, functional, and morphological properties, as well as microbiological safety for use as a food additive. The kefir was fortified with EBJ in concentrations of 1, 2.5, 5, and 7.5% (w/w), stored for up to 28 days under refrigeration, and periodically evaluated. Parameters such as the viscosity, titrable acidity, and pH indicate that the kefir fortification did not affect its stability during storage. EBJ significantly increased the antioxidant properties of the kefir, depending on the fortification level. Additionally, all the fortified samples provided more anthocyanins than the daily recommended intake. Microbiological profiling demonstrated that good laboratory practice and hygiene were implemented during the experiments. Finally, the panelists showed that higher EBJ concentrations in the kefir resulted in greater overall acceptability, indicating that this encapsulate has the potential to be a substitute synthetic color additive in the dairy industry.

Effects of simulated gastrointestinal digestion/epithelial transport on phenolics and bioactivities of particles of brewer's spent yeasts loaded with Brazilian red propolis

Red propolis from northeast Brazil contains mainly isoflavonoids as bioactive compounds, and its consumption may counteract unregulated and exacerbated formation of reactive oxygen species and inflammatory cytokines/chemokines. Moreover, the production of particles using sustainable carriers have been studied to increase the use of propolis as a functional food ingredient. Hence, the objective of this work was to investigate the effects of simulated gastrointestinal digestion followed by a cell-based epithelial transport on phenolic profile, anti-inflammatory and antioxidant activities of particles of brewer's spent yeasts (BSY) loaded with ethanolic extract of Brazilian red propolis (EEP). As a result, the EEP phenolic diversity decreased throughout the simulated gastrointestinal system, and was modulated by the particle production, as detected by high-performance liquid chromatography - electrospray ionization - quadrupole-time-of-flight-mass spectrometry (HPLC-ESI-QTOF-MS). Concomitantly, the antioxidant activity, as assessed by the ability to scavenge peroxyl and superoxide radicals, hydrogen peroxide, and hypochlorous acid, generally decreased at a higher extent for the particles of EEP with BSY (EEP-BSY) throughout the experiments. Nonetheless, after epithelial transport through the Caco-2 cell monolayer, the basolateral fraction of both EEP-BSY and EEP decreased the activation of pro-inflammatory transcription factor NF-κB by 83% and 65%, respectively, as well as the release of TNF-α (up to 51% and 38%, respectively), and CXCL2/MIP-2 (up to 33% and 25%, respectively). Therefore, BSY may be an interesting carrier for EEP bioencapsulation, since it preserves its anti-inflammatory activity. Further studies should be encouraged to investigate the feasibility of adding it in formulations of functional foods, considering its effect on sensory attributes.

Development of a novel functional yogurt rich in lycopene by Bacillus subtilis

Functional lycopene-rich yogurt displays attractive nutritious and health-promoting benefits among existing functional dairy products, owing to supplement with lycopene which could enhance immunity, prevent cancer, and cardiovascular diseases. Due to poor stability and fat-solubility of lycopene, its incorporation into yogurt is challengeable. In this study, carotenoid genes for lycopene synthesis were co-introduced into probiotic Bacillus subtilis for efficient lycopene production. Further engineered B. subtilis was applied as adjunct starter culture for achieving lycopene-rich yogurt. Developed yogurt exhibited desirable physiochemical characteristics compared with plain yogurt. Moreover, lycopene-rich yogurt was endowed with significantly high antioxidant capacity. More importantly, this functionalized yogurt had attractive sensorial attributes for quality-assured food to facilitate consumer acceptance. As the first report of fortifying yogurt of lycopene using B. subtilis with improved functional properties, this study offers a new and facile clue to enrich bioactive lycopene and probiotic B. subtilis in yogurt for healthy and nutritional food development.

Production and Evaluation of Yogurt Colored with Anthocyanin-Rich Pigment Prepared from Jabuticaba (Myrciaria cauliflora Mart.) Skin

Yogurt is known as a healthy food, but some synthetic additives that are commonly added to it can be one of the factors that restricts yogurt’s consumption. The aims of this study were to prepare and evaluate yogurts with the addition of spray-dried, anthocyanin-rich colorant extracted from jabuticaba (Myrciaria cauliflora Mart.) skin. The concentrated extract was spray-dried using maltodextrin (20 g/100 g w/w) as a carrier and added to yogurts in the concentrations of 0.5, 1.0, 1.5, and 2.0 g/100 g w/w. The yogurts were stored for up to 28 days under refrigeration and periodically evaluated. Except for the yogurts to which 1.5 g of extract was added, all samples had a slight pH reduction in the first 7 days of storage. Throughout the yogurts’ storage period, the anthocyanin and a* values were slightly reduced (p < 0.05), indicating some anthocyanin instability. The rheological behavior was typical for yogurts, but the casein gel network was probably disrupted by the jabuticaba extract incorporation, reducing the yogurt’s apparent viscosity. Panelists showed good acceptance for the attributes of taste, color, aroma, appearance, texture, and overall impression, indicating that this natural pigment has the potential to be a substitute synthetic color additive for the production of mixed berry yogurts, contributing to the reduction of waste.

The Wine Industry By-Products: Applications for Food Industry and Health Benefits

Each year, 20 million tons of wine by-products are generated, corresponding to 30% of the total quantity of vinified grapes. Wine by-products are a source of healthy bioactive molecules, such as polyphenols and other molecules (pigments, fibers, minerals, etc.). The abundance of bioactive compounds assures a promising future for nutritional foodstuff production. Wine by-products can be used to fortify aromatized waters and infusions, bread, pasta, dairy products, alcohol, sugary beverages, and processed foods. These innovative products are part of the Mediterranean diet and are of great interest to both human and environmental health. Pre-clinical studies show that consumption of food produced with wine by-products or with their extracts attenuates the inflammatory state and increases antioxidant status. As such, wine by-products provide protective effects against the underlying pathophysiological hallmarks of some chronic diseases such as atherosclerosis, diabetes, hypertension, obesity, and cancer. However, the poor bioavailability warrants further investigation on how to optimize the efficacy of wine by-products, and more clinical trials are also needed. The scientific evidence has validated the uses of the dietary nature of wine by-products and has helped to promote their use as a functional food to prevent chronic human diseases.

Sonoprocessing is an effective strategy to encapsulate fisetin into Saccharomyces cerevisiae cells

The encapsulation of fisetin into S. cerevisiae cells through sonoporation coupled with drying is reported for the first time in the literature. To establish the best conditions to maximize the amount of internalized fisetin, the cell density (5-10% w/v), fisetin concentration (1-3 mg/mL), acoustic energy density (0-333.3 W/L), and drying method (freeze-drying and spray drying) were analyzed through a Box-Behnken experimental design (BBD) coupled with response surface methodology (RSM). Higher encapsulation efficiency (EE) was achieved with a cell density of 10% w/v, while fisetin concentration of 3 mg/mL favored the encapsulation yield (EY) and antioxidant activity (AA). Higher EE (67.7%), EY (25.7 mg/g), and AA (90%) were registered when an acoustic density of 333.3 W/L was used. Furthermore, both drying protocols promoted fisetin encapsulation, but through spray drying, the EE, EY, and AA were 11.5%, 11.1%, and 26.6% higher than via freeze-drying, respectively. This work proved that fully filled biocapsules were produced through sonoprocessing, and their morphology was influenced by the acoustic energy and drying process. Overall, these results open new perspectives for the application of sonoprocessing-assisted encapsulation, paving the way for developing innovative yeast-based delivery systems for lipophilic compounds such as fisetin. KEY POINTS: • Sonoprocessing improves the encapsulation of fisetin into S. cerevisiae cells • Spray drying promotes fisetin loading into yeasts' intracellular space and cavities • Fisetin binding with yeast extracellular agents are favored by freeze-drying.

Ultrasound-assisted encapsulation of curcumin and fisetin into Saccharomyces cerevisiae cells: a multistage batch process protocol

Some of the challenges of yeast encapsulation protocols are low phytochemical internalization rates and limited intracellular compartment of yeasts. This study uses an ultrasound-assisted batch encapsulation (UABE) protocol to optimize the encapsulation of curcumin and fisetin by recovering non-encapsulated biomaterial and further incorporating it into non-loaded yeasts in three encapsulation stages (1ES, 2ES, and 3ES). The effect of selected acoustic energies (166.7 and 333.3 W L^-1 ) on the encapsulation efficiency (EE), yield (EY), and antioxidant activity retention were evaluated, and then, compared with a control process (without ultrasound treatment). Compared to the control, enhanced EEs were achieved for both curcumin (10.9% control to 58.5% UABE) and fisetin (18.6% control to 76.6% UABE) after 3ES and the use of 333.3 W L^-1 . Similarly, the yeast maximum loading capacity was improved from 6.6 to 13.4 mg g^-1 for curcumin; and from 11.1 to 26.4 mg g^-1 for fisetin after UABE protocol. The antioxidant activity of produced biocapsules was positively correlated with the bioactive loaded content of yeasts when ultrasound treatment was applied. Overall, results from this study provide valuable information regarding UABE processes, and moreover, bring new and creative perspectives for the ultrasound technology in the food industry.

Investigation of brewer’s spent yeast as a bio-vehicle for encapsulation of natural colorants from pumpkin (Cucurbita moschata) peels

Brewer’s spent yeast (BSY) Saccharomyces cerevisiae has been currently explored as a bio-vehicle for encapsulation of bioactive compounds and as a delivery system. The main objectives of this work were...