Chia mucilage carrier systems: A review of emulsion, encapsulation, and coating and film strategies

Nanoencapsulation with Eudragit® and chia mucilage increases the stability and antifungal efficacy of carvacrol against Aspergillus spp

Carvacrol is a consolidated natural antimicrobial. However, its use in food is a challenge due to characteristic odour and high volatility. Nanoencapsulation has emerged to overcome these drawbacks. Aspergillus spp. represent a concern in grapes for causing rot and producing mycotoxins. This study aimed to evaluate the effect of carvacrol (unencapsulated and loaded into Eudragit® and chia nanocapsules) on the growth of Aspergillus species. Spore germination and mycelial growth of Aspergillus spp. were evaluated using the agar dilution culture method. The stability of nanocapsules during storage was monitored monthly by evaluating the particle size distribution, polydispersity index, and zeta potential. Antifungal and antitoxigenic effectiveness of nanocapsules were assessed by counting fungal colony-forming units and determining mycotoxin levels in grapes. A dose-dependent effect of carvacrol (unencapsulated and encapsulated forms) on spore germination and mycelial growth was observed. During 180 days of storage, carvacrol into Eudragit® nanocapsules preserved their nanometric dimensions, whereas chia nanocapsules maintained this characteristic for 30 days. The antifungal effectiveness of both encapsulated forms persisted for 210 days. No mycotoxin was found, even when fungal growth was not completely suppressed. Nanoencapsulated carvacrol proved to be a new promising antifungal product to ensure quality and safety in the grape production chain.

Chia Oil Nanoemulsion Using Chia Mucilage as a Wall Material: An Alternative for Cracker Fat Substitution

Crackers are bakery products that have shown an increase in consumption. One way to make crackers more nutritious is to add bioactive compounds, such as chia oil which is rich in polyunsaturated fatty acids. As these compounds are highly unsaturated, encapsulation techniques, such as nanoemulsion, allow the addition of them in foods, guaranteeing the preservation of their properties. Thus, the objective was to add chia oil nanoemulsion prepared with chia mucilage, in total replacement of water and soybean oil in crackers, and to evaluate the physical-chemical, technological, and sensory properties. The cracker with chia oil nanoemulsion showed a 73.2% reduction in lipid content compared to the control cracker, and no difference in protein and fiber content. The developed cracker presented expansion, firmness, fracture, and luminosity factors as the control cracker. Regarding antioxidant activity, the cracker with nanoemulsion showed greater activity. Sensorially, the developed crackers did not show a significant difference in appearance, flavor, and texture from the control cracker, and the purchase intention was positive. Also, the developed crackers were healthier, with a lower total lipid content, and higher antioxidant activity.

Enhancing mechanical and water barrier properties of starch film using chia mucilage

Biodegradable packaging materials are increasingly being investigated due to rising concerns about food safety and environmental conservation. This study examines the incorporation of chia mucilage (CM) into starch-based films using the casting method, aiming to understand its effects on the structure and functionality of the films. CM, an anionic heteropolysaccharide, is hypothesized to enhance the mechanical and barrier properties of the films through polymer interactions and hydrogen bonding. Our findings confirm that CM incorporation results in films with uniformly smooth surfaces, indicating high compatibility and homogeneity within the starch matrix. Notably, CM improves film transparency and crystallinity. Mechanical assessments show a remarkable elevation in tensile strength, soaring from 5.21 MPa to 12.38 MPa, while elongation at break decreases from 61.73 % to 31.42 %, indicating a trade-off between strength and flexibility. Additionally, water solubility decreases from 57.97 % to 41.40 %, and water vapor permeability is reduced by 30 % with CM loading. These results highlight the role of CM in facilitating the formation of a dense, interconnected polymeric network within the starch matrix. Given the soluble dietary fiber nature of CM, the CS/CM (corn starch/chia mucilage) blended films are expected to be safe for food packaging and applicable as edible films with health benefits.

Carvacrol nanocapsules as a new antifungal strategy: Characterization and evaluation against fungi important for grape quality and to control the synthesis of ochratoxins

Fungi are a problem for viticulture as they can lead to deterioration of grapes and mycotoxins production. Despite the widespread use of synthetic fungicides to control fungi, their impact on the agricultural ecosystem and human health demand safer and eco-friendly alternatives. This study aimed to produce, characterize and assess the antifungal activity of carvacrol loaded in nanocapsules of Eudragit® and chia mucilage as strategy for controlling Botrytis cinerea, Aspergillus flavus, Aspergillus carbonarius, and Aspergillus niger. Eudragit® and chia mucilage were suitable wall materials, as both favored the encapsulation of carvacrol into nanometric diameter particles. Fourier Transform Infrared Spectroscopy (FTIR) analysis suggested a successful incorporation of carvacrol into both nanocapsules, which was confirmed by presenting a good encapsulation efficiency and loading capacity. Thermogravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC) analyses revealed adequate thermal resistance. All fungi were sensible to carvacrol treatments and B. cinerea was the most sensitive compared to the Aspergillus species. Lower concentrations of encapsulated carvacrol than the unencapsulated form were required to inhibit fungi in the in vitro and grape assays. Additionally, lower levels of carvacrol (unencapsulated or encapsulated) were used to inhibit fungal growth and ochratoxin synthesis on undamaged grapes in comparison to those superficially damaged, highlighting the importance of management practices designed to preserve berry integrity during cultivation, storage or commercialization. When sublethal doses of carvacrol were used, the growth of A. niger and A. carbonarius was suppressed by at least 45 %, and ochratoxins were not found. The nanoencapsulation of carvacrol using Eudragit® and chia mucilage has proven to be an alternative to mitigate the problems with fungi and mycotoxins faced by the grape and wine sector.