Synergistic effects of starch nanoparticles and chitin nanofibers on the stability of oil-in-water Pickering emulsions

Thermal stability and in vitro digestive behavior of Pickering emulsion stabilized by high-amylose starch nanocrystals

In this study, high-amylose starch (HAS) was processed using sulfuric acid-ultrasonic cross-linking to produce high-amylose starch nanocrystals (HASNC). These nanocrystals were used to stabilize Pickering emulsions and assess their effectiveness in encapsulating β-carotene. Normal starch nanocrystals (NSNC) were prepared similarly for comparison. The HASNC retained key HAS properties, such as heat and enzyme resistance, providing several advantages to HASNC-stabilized emulsions. First, after exposure to 100 °C heat and in vitro tests simulating the mouth and stomach, the HASNC-stabilized emulsions demonstrated significantly greater stability and higher β-carotene retention compared to the NSNC-stabilized emulsions. This enhanced stability is attributed to the lower gelatinization degree and increased resistance to α-amylase hydrolysis of HASNC, which provides stronger steric stabilization of the oil droplets. Second, during in vitro small intestine tests, the greater enzyme resistance of HASNC allowed for the formation of a denser barrier around the oil droplets, effectively preventing lipase and bile salts from contacting the oil droplets. This led to a reduced rate and extent of lipid digestion and facilitated a sustained-release effect. Consequently, HASNC, as a starch-based emulsifier, show great potential as an effective delivery system for the sustained release of bioactive compounds.

Enhanced stabilization of multifunctional phenolic acids-grafted chitin nanofibers for Pickering emulsions

The objective of this study was to develop novel functional stabilizers for Pickering emulsions using phenolic acids-grafted chitin nanofibers (phenolic acids-g-ChNF), which were fabricated by grafting ferulic acid (FA), sinapic acid (SA) and caffeic acid (CA) onto ChNF via free radical-mediated method. The Fourier transform infrared spectrum and Proton nuclear magnetic resonance showed that graft copolymerization occurred between the amino groups of ChNF and the carbonyl of the phenolic acids. Further, it was revealed that CA-g-ChNF and SA-g-ChNF possessed stronger antioxidant and antibacterial properties than the original ChNF and FA-g-ChNF. Additionally, we applied phenolic acids-g-ChNF to develop Pickering emulsions and found that SA-g-ChNF- and CA-g-ChNF-stabilized emulsions displayed reduced droplet sizes compared to FA, the main reason for which was that SA and CA had a rather close bonding relationship with ChNF. Taken together, SA-g-ChNF and CA-g-ChNF as novel multi-functional particles can be employed for facilitating the stability of Pickering emulsions.

Chitin nanofibers prepared by enzymatic hydrolysis: Characterization and application for Pickering emulsions

Chitin nanofibers (ChNFs) have a wide range of applications in numerous fields owing to their exceptional material properties and biological functionality. This research focused on producing ChNFs with diameters of 20-70 nm using chitinase and ultrasound from crayfish shells. The impact of enzymatic duration on ChNF yield and performance was investigated. Results revealed ChNFs forming a high aspect ratio network structure. Chitinase hydrolysis enhanced ChNF dispersion and yield while improving crystallinity and thermal stability without significantly altering their chemical structure. Enzymatically modified ChNF suspensions also exhibited stable rheological properties. Moreover, ChNFs showed good emulsification and emulsion stability in Pickering emulsion. The mechanism may be the effective adsorption of ChNFs at the oil-water interface, and the formation of a ChNF network in the continuous phase that prevents droplet coalescence. This study highlights that the potential of chitinase and ultrasound for the production of ChNFs and the utilization of crayfish shell waste.

Research progress on chitin/chitosan-based emulsion delivery systems and their application in lipid digestion regulation

Excessive lipid intake is linked to an elevated risk of health problems. However, reducing lipid contents may influence food structure and flavor. Some alternatives are needed to control the lipid absorption. Emulsions are common carriers for lipids, which can control the hydrolysis and absorption of lipids. Chitin (Ch) and chitosan (CS) are natural polysaccharides with good biodegradability, biocompatibility, and unique cationic properties. They have been reported to be able to delay lipolysis, which can be regarded as one of the most promising agents that regulates lipid digestion (LiD). The application of Ch/CS and their derivatives in emulsions are summarized in this review with a focus on their performances and mechanisms for LiD regulation, aiming to provide theoretical guidance for the development of novel Ch/CS emulsions, and the regulation of LiD. A reasonable design of emulsion interface can provide its resistance to the external environment and then control LiD. The properties of emulsion interface are the key factors affecting LiD. Therefore, systematic study on the relationship between Ch/CS-based emulsion structure and LiD can not only instruct the reasonable design of emulsion interface to accurately regulate LiD, but also provide scientific guidelines for applying Ch/CS in functional food, medicine and other fields.

Advances in Starch Nanoparticle for Emulsion Stabilization

Starch nanoparticles (SNPs) are generally defined as starch grains smaller than 600-1000 nm produced from a series of physical, chemical, or biologically modified starches. Many studies have reported the preparation and modification of SNPs, which are mostly based on the traditional "top-down" strategy. The preparation process generally has problems with process complexity, long reaction periods, low yield, high energy consumption, poor repeatability, etc. A "bottom-up" strategy, such as an anti-solvent method, is proven to be suitable for the preparation of SNPs, and they are synthesized with small particle size, good repeatability, a low requirement on equipment, simple operation, and great development potential. The surface of raw starch contains a large amount of hydroxyl and has a high degree of hydrophilicity, while SNP is a potential emulsifier for food and non-food applications.

Application of Pickering emulsions stabilized by corn, potato and pea starch nanoparticles: Effect of environmental conditions and approach for curcumin release

To apply octenyl succinic anhydride (OSA)-modified corn, potato and pea starch nanoparticles (OCSNPs, OPtSNPs and OPSNPs, respectively) as Pickering emulsion stabilizers, effect of environmental conditions such as 30 days of storage period, pH of 1-11, ionic strength of 0.1-0.9 mol/L and heat of 30-90 °C on the stability of the emulsions was evaluated. Compared with emulsions stabilized by starch nanoparticles (SNPs), the emulsions stabilized by OSA-modified SNPs (OSNPs) kept stable against different environmental stresses (pH, ionic strength and heat) as well as for a storage period of 30 days, especially for OPtSNPs. Additionally, oiling-off was not observed in OSNPs emulsions over the storage time. OSNPs emulsions also showed improved protection on curcumin during storage and controlled release during in vitro digestion. These findings enlarged the application of OCSNPs, OPtSNPs and OPSNPs stabilized-Pickering emulsion in food systems and deliver system.

Development, application and future trends of starch-based delivery systems for nutraceuticals: A review

As a natural biopolymer, starch is ideally adapted as an encapsulant material for nutraceutical delivery systems due to its unique nature of extensive sources, versatility and high biocompatibility. This review offers an outline of recent advances in the development of starch-based delivery systems. The structure and functional properties of starch in encapsulating and delivering bioactive ingredients are first introduced. Structural modification of starch improves the functionalities and extends the applications of starch in novel delivery systems. Then, various nutraceutical delivery systems are systematically summarized, which include porous starch, starch particle, amylose inclusion complex, cyclodextrin, gel, edible film and emulsion. Next, the delivery process of nutraceuticals is discussed in two parts: digestion and release. Intestinal digestion plays an important role during the whole digestion process of starch-based delivery systems. Moreover, controlled release of bioactives can be achieved by porous starch, starch-bioactive complexation and core-shell structure. Finally, the challenges of the existing starch-based delivery systems are deliberated, and the directions for future research are pointed out. Composite delivery carriers, co-delivery, intelligent delivery, delivery in real food systems, and reuse of agricultural wastes may be the research trends for starch-based delivery systems in the future.

A novel chitinous nanoparticles prepared and characterized with black soldier fly (Hermetia illucens L.) using steam flash explosion treatment

This is the first report of the use of steam flash explosion (SFE) to prepare chitinous nanoparticles from black soldier fly (BSF). SFE treatment was performed at a steam pressure of 0.45 to 1.60 MPa with a holding time of 60 s. As the pressure increased, the particle size of the chitinous particles decreased. Under SFE at 1.60 MPa, chitinous nanoparticles with sizes ranging from 59 to 162 nm were produced. SEM, AFM, Raman spectroscopy, FT-IR spectroscopy, ¹H NMR, TGA, and DSC were used to characterize the BSF chitin materials. It was demonstrated that SFE treatment deacetylated chitin to obtain chitosan with 91.24 % deacetylation. In addition, the polymer backbone was maintained, and the degree of polymerization of chitosan nanoparticles was reduced. The activity of the cationic groups of chitosan nanoparticles was improved, thereby enhancing the temperature sensitivity of the polymeric material. It can be concluded that the SFE one-step processing method is a simple and efficient way to prepare homogeneous biomaterial nanoparticles. This study has implications for the development of chitosan nanomaterials for biomedical applications.

Chitin and chitin-based biomaterials: A review of advances in processing and food applications

Chitin is the most abundant natural amino polysaccharide, showing various practical applications owing to its functional properties. However, there are barriers in the development due to the difficulty of chitin extraction and purification, regarding its high crystallinity and low solubility. In recent years, some novel technologies such as microbial fermentation, ionic liquid, electrochemical extraction have emerged for the green extraction of chitin from new sources. Furthermore, nanotechnology, dissolution systems and chemical modification were applied to develop a variety of chitin-based biomaterials. Remarkably, chitin was used in delivering active ingredients and developing functional foods for weight loss, lipid reduction, gastrointestinal health, and anti-aging. Moreover, the application of chitin-based materials was expanded into medicine, energy and the environment. This review outlined the emerging extraction methods and processing routes of different chitin sources and advances in applying chitin-based materials. We aimed to provide some direction for the multi-disciplinary production and application of chitin.

Environmental Properties and Applications of Biodegradable Starch-Based Nanocomposites

In recent years, the demand for environmental sustainability has caused a great interest in finding novel polymer materials from natural resources that are both biodegradable and eco-friendly. Natural biodegradable polymers can displace the usage of petroleum-based synthetic polymers due to their renewability, low toxicity, low costs, biocompatibility, and biodegradability. The development of novel starch-based bionanocomposites with improved properties has drawn specific attention recently in many applications, including food, agriculture, packaging, environmental remediation, textile, cosmetic, pharmaceutical, and biomedical fields. This paper discusses starch-based nanocomposites, mainly with nanocellulose, chitin nanoparticles, nanoclay, and carbon-based materials, and their applications in the agriculture, packaging, biomedical, and environment fields. This paper also focused on the lifecycle analysis and degradation of various starch-based nanocomposites.

Study on stability of grape seed oil/rice hydrolyzed protein emulsion

In this study, the stability mechanism of grape seed oil/rice hydrolyzed protein emulsion was studied. The grape seed oil (10% v/v) and rice hydrolyzed protein (2% w/v) were homogenized under high pressure to prepare the emulsion. It was observed by CLSM and Multiple light scatterometer that the emulsion had long-term storage stability, and the average particle size of droplets was 0.984–1.363 µm. ζ-potential ranged from −37.733 mV to −25.633 mV. It is found that the emulsion has strong resistance to temperature, ions and other environmental factors from the macroscopic and microscopic structure, and no emulsion stratification phenomenon occurs. The composite emulsion can be used in the field of food industry and fine chemical industry, which can provide nutrition and functionality of products, its research has certain value and has a wide space for development.

Pickering emulsion stabilized by composite-modified waxy corn starch particles

The starch-based Pickering stabilizer has attracted more research interest recently, however, its application in food system is limited due to the low digestibility of raw starch particles. In this study, waxy corn starches were modified with octenyl succinic anhydride and then treated by dry heating at 180 °C for 20-60 min. Pickering emulsions stabilized by the composite-modified starch particles were fabricated, the physical stability, rheology property and microstructure of the emulsions were investigated. The results showed that the composite-modified starches maintained granule structure, their gelatinization temperatures and enthalpy significantly reduced after heat treatment (p < 0.05). Compared with native starch, the composite-modified starches had bigger three-phase contact angles and higher in vitro digestibility, while the relative crystallinity decreased from 32.46% to 24.87%. Pickering emulsions stabilized by composite-modified starch particles had long-term stability up to 300 days. The rheology results showed that all emulsions exhibited pseudoplastic behaviors and had higher storage modulus than loss modulus. Moreover, the viscosities decreased when the starch was roasted for 40 and 60 min. The composite-modified starch particles and few starch macromolecules at oil-water interface stabilized the emulsions collectively. These results provide a new strategy for designing an edible Pickering stabilizer.

Pleurotus eryngii polysaccharide nanofiber containing pomegranate peel polyphenol/chitosan nanoparticles for control of E. coli O157:H7

Pomegranate peel polyphenols (PPP), which are natural, safe, and green antibacterial agents, were introduced and embedded in chitosan to form stable nanoparticles. The PPP@chitosan nanoparticles (PPP@CNPs) were further electrospun into nanofibers based on Pleurotus eryngii polysaccharide (PEP). The preferable distribution of particle size, polydispersity index, and zeta potential was realized through the addition of PPP at 3 mg/mL, which achieved the highest encapsulation rate of 23.71 ± 0.51%. The tensile strength and elongation at break of nanofibers reached 15.76 MPa and 0.69% with the addition of 1% PEP through electrospinning. The results of scanning electron microscopy (SEM) and atomic force microscopy (AFM) demonstrated that the addition of nanoparticles increased the diameter of PEP nanofibers from 148 nm to 163 nm, and the surface roughness of the fibers also increased. Meanwhile, the addition of nanoparticles improved the thermal stability of PEP nanofibers. PPP@CNPs/PEP nanofibers can inhibit the growth of E. coli O157:H7 on pork and cucumber surfaces during the five-days storage, and the inhibition rates were all above 95%. Besides, the nanofibers did not have any impact on the color and texture of foods.