Changes in the structure and enzyme binding of starches during in vitro enzymatic hydrolysis using mammalian mucosal enzyme mixtures.

Starches are hydrolyzed into monosaccharides by mucosal α-glucosidases in the human small intestine. However, there are few studies assessing the direct digestion of starch by these enzymes. The objective of this study was to investigate the changes in the structure and enzyme binding of starches during in vitro hydrolysis by mammalian mucosal enzymes. Waxy maize (WMS), normal maize (NMS), high-amylose maize (HAMS), waxy potato (WPS), and normal potato (NPS) starches were examined. The order of the digestion rate was different compared with other studies using a mixture of pancreatic α-amylase and amyloglucosidase. NPS was digested more than other starches. WPS was more digestible than WMS. Hydrolyzed starch from NPS, NMS, WPS, WMS, and HAMS after 24 h was 66.4, 64.2, 61.7, 58.7, and 46.2 %, respectively. Notably, a significant change in the morphology, reduced crystallinity, and a decrease in the melting enthalpy of the three starches (NPS, NMS, and WPS) after 24 h of hydrolysis were confirmed by microscopy, X-ray diffraction, and differential scanning calorimetry, respectively. The bound enzyme fraction of NPS, NMS, and WPS increased as hydrolysis progressed. In contrast, HAMS was most resistant to hydrolysis by mucosal α-glucosidases in terms of digestibility, changes in morphology, crystallinity, and thermal properties.

Unveiling the significance of gastric digestion in gastrointestinal fate of octenylsuccinylated starch-stabilized emulsions.

The importance of gastric digestion in starch-based emulsion is often overshadowed compared to intestinal digestion, despite acknowledging the activity of salivary α-amylase in the stomach. This study aimed to address this gap by investigating the digestion of starch-based emulsions through orogastrointestinal digestion experiments. Our observations revealed the crucial role of salivary α-amylase, which hydrolyzed ∼8 %, ∼56 %, and âˆ¼ 28 % of starch in emulsions stabilized by octenylsuccinylated maize starch (OMS-E), gelatinized OMS (GOMS-E), and retrograded OMS (ROMS-E), respectively, during the gastric phase. Consequently, ∼23 % of the oil in GOMS-E underwent lipolysis during this phase, whereas ∼13 and âˆ¼ 6 % of the oil was lipolyzed in OMS-E and ROMS-E, respectively. These phenomena significantly influenced their small intestinal digestion and the bioaccessibility of encapsulated curcumin. Notably, GOMS-E exhibited ∼28 % lower curcumin bioaccessibility than that of curcumin encapsulated in OMS-E or ROMS-E. This difference was attributed to premature gastric digestion and subsequent encapsulant release in the case of GOMS-E. This understanding can be utilized to manipulate the delivery and digestion of starch-based emulsions. Importantly, our findings highlight the necessity of considering gastric amylolysis and lipolysis when investigating the gastrointestinal fate of starch-based emulsions.

Upcycling Lactobacillus casei culture waste into vegan cheese analogue using inulin, locust bean gum, and κ-carrageenan.

The growing popularity of probiotics has led to the generation of substantial by-products. Among these, cell-free supernatant is recognized for containing beneficial postbiotics. Here, we upcycled Lactobacillus casei-free supernatant (LFS) into cheese analogues using inulin (INU), locust bean gum (LBG), and kappa-carrageenen (kCG). In this system, LBG/kCG established the primary structure, while interstitial spaces were progressively filled by INU. Despite the absence of milk proteins and fats, the cheese analogue with 35% w/w INU, 0.2% w/w LBG, and 0.8% kCG exhibited a texture and appearance resembling commercial processed cheese, as determined by texture profile analysis and dynamic small amplitude oscillatory rheometry technique. This can be attributed to the effective fat-replacing activity of INU regarding texture and rheology. Furthermore, the potassium-dominated salt composition of LFS proved advantageous for the LBG/kCG-derived structure-forming. These findings hold significant promise for upcycling probiotics wastewater into low-fat vegan cheese analogues, enriched with both prebiotics and postbiotics.

Characterization of yeast protein isolates extracted via high-pressure homogenization and pH shift: A promising protein source enriched with essential amino acids and branched-chain amino acids.

In the global food industry, plant-based protein isolates are gaining prominence as an alternative to animal-based counterparts. However, their nutritional value often falters due to insufficient essential amino acids. To address this issue, our study introduces a sustainable protein isolate derived from yeast cells, achieved through high-pressure homogenization (HPH) and alkali pH-shifting treatment. Subjected to HPH pressures ranging from 60 to 120 MPa and 1 to 10 cycles, higher pressure and cycle numbers resulted in enhanced disruption of yeast cells. Combining HPH with alkali pH-shifting treatment significantly augmented protein extraction. Four cycles of HPH at 100 MPa yielded the optimized protein content, resulting in a yeast protein isolate (YPI) with 75.3 g protein per 100 g powder, including 30.0 g of essential amino acids and 18.4 g of branched-chain amino acids per 100 g protein. YPI exhibited superior water and oil-holding capacities compared to pea protein isolate, whey protein isolate (WPI), and soy protein isolate. Although YPI exhibited lower emulsifying ability than WPI, it excelled in stabilizing protein-stabilized emulsions. For foaming, YPI outperformed others in both foaming ability and stabilizing protein-based foam. In conclusion, YPI surpasses numerous plant-based protein alternatives in essential amino acids and branched-chain amino acids contents, positioning it as an excellent candidate for widespread utilization as a sustainable protein source in the food industry, owing to its exceptional nutritional advantages, as well as emulsifying and foaming properties. PRACTICAL APPLICATION: This study introduces a sustainable protein isolate derived from yeast cells. YPI exhibited considerable promise as a protein source. Nutritionally, YPI notably surpassed plant-based protein isolates in EAA and BCAA contents. Functionally, YPI demonstrated superior water-holding and oil-holding capacities, as well as an effective emulsion and foam stabilizer.

Citrus peel pectin and alginate-based emulgel particles for small intestine-targeted oral delivery of curcumin.

Polysaccharides are a prominent choice in the realm of food-grade oral delivery systems due to their resistance to degradation by digestive enzymes in the oral, gastric, and small intestinal environments, as well as their ease of production, cost-effectiveness, and potential health benefits as prebiotics. Furthermore, their ability to respond to pH-induced dissolution, along with their emulsifying properties, can be strategically employed to achieve precise targeting of lipophilic bioactives to the small intestine. In this study, citrus peel pectin and alginate served as stabilizers for emulgel particles without supplementary emulsifiers or gelling agents. Within this system, pectin functioned as an emulsifier, while alginate acted as a gelling agent, facilitated by Ca2+-induced ionic crosslinking. The synergistic interplay between pectin and alginate efficiently protected curcumin in gastric conditions and controlled dissolution in the small intestine, depending on the pectin/alginate ratio. These controlled phenomena facilitated lipolysis, curcumin release, and ultimately enhanced curcumin bioaccessibility. Furthermore, once the emulgel particle released all the entrapped curcumin in the small intestine, residual polysaccharides underwent facile degradation by pectinase and alginate lyase, yielding fermentable monosaccharides. This confirms the potential of the emulgel particles for use as a prebiotic in the colon. These findings offer significant promise for enhancing the systematic design of food-grade delivery systems that encapsulate lipophilic bioactives, achieving controlled release, enhanced stability, and improved bioaccessibility. Importantly, this system can comprise components that undergo complete digestion, absorption, and utilization in the human body, encompassing materials such as oil, nutraceuticals, and prebiotics, all without presenting health risks.

Retrograded octenylsuccinylated maize starch-based emulgels for a promising oral delivery system of curcumin.

Emulgels are a type of soft solid delivery system that exploit the merits of both emulsions and gels, namely, bioactive encapsulability and structural stability, respectively. We utilized retrograded/octenylsuccinylated maize starch (ROMS) to fabricate the curcumin-loaded emulgel. Emulgels (oil volume fraction, 0.20) prepared with 1-4 % w/w ROMS exhibited fluid-like behaviors while emulgels with 5-8 % w/w ROMS exhibited a gel-like consistency. Compared to a fluidic emulsion stabilized with 3 % w/w octenylsuccinylated maize starch, the emulgels showed more sustained lipolysis and controlled curcumin release patterns. These results were attributed to rigid ROMS structures at the outer layer of oil droplets, hindering the lipase approach onto the oil/water interface and curcumin diffusion from the interface. Additionally, the bioaccessibility of curcumin in ROMS-stabilized emulgels was enhanced >9.6-fold compared to that of a curcumin solution. Furthermore, emulgels prepared with 8 % w/w ROMS exhibited a high yield stress (376.4 Pa) and maintained appearance and droplet size for 60 days of storage at 4 °C. Consequently, this emulgel has potential as a lipophilic bioactive-containing soft gel with sustained digestion and controlled release properties. Our findings may provide insights into rational delivery system designs.

Rheology, Microstructure, and Storage Stability of Emulsion-Filled Gels Stabilized Solely by Maize Starch Modified with Octenyl Succinylation and Pregelatinization.

We prepared emulsion-filled gels stabilized using octenyl succinic anhydride-modified and pregelatinized maize starch (OSA-PGS). The effect of the oil volume fraction (Φ, 0.05-0.20) and OSA-PGS concentration (3-10% w/v) on the rheological and microstructural properties of the emulsion-filled gels was evaluated. Confocal fluorescence images showed that OSA-PGS stabilized the emulsion, indicated by the formation of a thick layer surrounding the oil droplets, and simultaneously gelled the aqueous phase. All of the emulsions exhibited shear-thinning flow behavior, but only those with 10% w/v OSA-PGS were categorized as Herschel-Bulkley fluids. The rheological behavior of the emulsion-filled gels was significantly affected by both the OSA-PGS concentration and Φ. The mean diameters (D1,0, D3,2, and D4,3) of oil droplets with 10% w/v OSA-PGS were stable during 30 days of storage under ambient conditions, indicating good stability. These results provide a basis for the design of systems with potential applications within the food industry.

Enhancing the oral bioavailability of curcumin using solid lipid nanoparticles.

To control the oral bioavailability of curcumin, we fabricated solid lipid nanoparticles (SLNs) using tristearin and polyethylene glycol (PEG)ylated emulsifiers. Lipolysis of prepared SLNs via simulated gastrointestinal digestion was modulated by altering the types and concentrations of emulsifiers. After digestion, the size/surface charge of micelles formed from SLN digesta were predictable and >91% of curcumin was bioaccessible in all of the SLNs. The curcumin permeation rate through mucus-covered gut epithelium in vitro was dependent on the size/surface charge of the micelles. Curcumin loaded in long-PEGylated SLNs rapidly permeated the epithelium due to the neutral surface charge of the micelles, resulting in a >12.0-fold increase in bioavailability compared to curcumin solution in a rat model. These results suggest that the bioavailability of curcumin can be controlled by modulating the interfacial properties of SLNs, which will facilitate the development of curcumin formulations for use in functional foods and pharmaceuticals.

Interfacial and colloidal characterization of oil-in-water emulsions stabilized by interface-tunable solid lipid nanoparticles.

We evaluated the correlation between the interfacial characteristics of solid lipid nanoparticles (SLNs) and the interfacial/colloidal stability of SLN-stabilized emulsions. Herein, the interfacial properties of SLNs, particularly the surface load (Γs) of emulsifiers, were tuned by controlling the type/concentration of emulsifier used to prepare the SLNs. Increasing the Γs decreased the contact angle at the oil-water interface, which enhanced the displacement free energy of the SLNs at the interface. Moreover, the Γs of emulsifiers bound to the surface of SLNs covering oil droplets was linearly correlated with the SLN-own Γs. The size/ζ-potential of emulsions stabilized by SLNs covered by the highest concentration of emulsifiers was unchanged for 1 month, indicating good emulsion stability. The interfacial/colloidal stability of SLN-stabilized emulsions was thus enhanced by increasing the emulsifier concentration used to produce the SLNs. This study provides baseline data for developing SLN-stabilized emulsions for the food, cosmetic, and pharmaceutical industries.

Control of the gastrointestinal digestion of solid lipid nanoparticles using PEGylated emulsifiers.

We prepared solid lipid nanoparticles (SLNs) with tristearin and various emulsifiers which had different chain length PEGs (10-100 times-repetition of ethylene glycol) to control their digestion fate in the gastrointestinal tract. Fabricated SLNs after acidic/high-ionic-strength media treatment were stable regardless of the ζ-potential (ZP) disappearance. Additionally, highly PEGylated SLNs successfully hindered the adsorption of both bile acid (BA) and lipase on the SLN surface, while lowly PEGylated SLNs interrupted that of only lipase. In simulated small intestinal fluid, lipolysis of highly PEGylated SLNs increased with decrease of the emulsifier density on the SLNs, whereas lipolysis of lowly PEGylated SLNs increased with decrease of the particle size. These results suggested that high PEGylation was more efficient than low PEGylation to hinder the lipolysis initiated from the competitive replacement of the SLN-covering emulsifiers with BAs. Consequently, the SLN digestion could be controlled by choosing the length and concentration of PEGylated emulsifiers.