Stability and Biaxial Behavior of Fresh Cheese Coated with Nanoliposomes Encapsulating Grape Seed Tannins and Polysaccharides Using Immersion and Spray Methods.

In the food industry context, where fresh cheese stands out as a highly perishable product with a short shelf life, this study aimed to extend its preservation through multi-layer edible coatings. The overall objective was to analyze the biaxial behavior and texture of fresh cheese coated with nanoliposomes encapsulating grape seed tannins (NTs) and polysaccharides (hydroxypropyl methylcellulose; HPMC and kappa carrageenan; KC) using immersion and spray methods, establishing comparisons with uncoated cheeses and commercial samples, including an accelerated shelf-life study. NT, HPMC, and KC were employed as primary components in the multi-layer edible coatings, which were applied through immersion and spray. The results revealed significant improvements, such as a 20% reduction in weight loss and increased stability against oxidation, evidenced by a 30% lower peroxide index than the uncoated samples. These findings underscore the effectiveness of edible coatings in enhancing the quality and extending the shelf life of fresh cheese, highlighting the innovative application of nanoliposomes and polysaccharide blends and the relevance of applying this strategy in the food industry. In conclusion, this study provides a promising perspective for developing dairy products with improved properties, opening opportunities to meet market demands and enhance consumer acceptance.

Physicochemical Properties of Nanoliposomes Encapsulating Grape Seed Tannins Formed with Ultrasound Cycles.

Grape seeds are an excellent source of flavonoids and tannins with powerful antioxidant properties. However, the astringency of tannins limits their direct incorporation into food. To overcome this challenge, we investigated the encapsulation of grape seed tannins within nanoliposomes formed by ultrasound cycling. We characterized the nanoliposomes' physicochemical properties, including encapsulation efficiency, antioxidant activity, stability, microstructure, and rheological properties. Our findings reveal that the nanoliposomes exhibited excellent stability under refrigerated conditions for up to 90 days with a mean particle size of 228 ± 26 nm, a polydispersity index of 0.598 ± 0.087, and a zeta potential of -41.6 ± 1.30 mV, maintaining a spherical multilamellar microstructure. Moreover, they displayed high antioxidant activity, with encapsulation efficiencies of 79% for epicatechin and 90% for catechin. This innovative approach demonstrates the potential of using ultrasound-assisted nanoliposome encapsulation to directly incorporate grape seed tannins into food matrices, providing a sustainable and efficient method for enhancing their bioavailability and functionality.

Mechanical and Surface Properties of Edible Coatings Elaborated with Nanoliposomes Encapsulating Grape Seed Tannins and Polysaccharides.

Edible composite coatings (ECC) formulated from biopolymers that incorporate antioxidant molecules represent an innovative alternative to improve food texture and provide health benefits. Tannins have aroused great interest due to their ability to stabilize suspensions and counteract the effects of free radicals. The mechanical and surface properties are crucial to establishing its quality and applicability. In this study, the objective was to analyze the mechanical and surface properties of ECC made with nanoliposomes that encapsulate grape seed tannins (TLS) and polysaccharides such as hydroxypropylmethylcellulose (HPMC) and kappa carrageenan (KCG) for their future direct application in foods susceptible to oxidation. The inclusion of HPMC or KCG affected the density, showing values in the range of 1010 to 1050 [kg/m3], evidencing significant changes (p < 0.05) in the surface tension in the TLS/FS-HPMC and TLS/FS mixtures. KCG and in the dispersion coefficients, with values in the range of -2.9 to -17.6 [mN/m] in HPS (S1) and -17.6 to -40.9 [mN/m] in PDMS (S2). The TLS/FS-HPMC coating showed higher stiffness and elastic recovery capacity than the TLS/FS-KCG coating, suggesting that the presence of TLS influenced the stiffness of the polymer. HPMC is recommended as a suitable polymer for coating solids, while KCG is more appropriate for suspensions. These findings provide valuable information for directly applying these ECC compounds to food products, potentially offering better preservation and health benefits.

Lipid-Encapsuled Grape Tannins Prevent Oxidative-Stress-Induced Neuronal Cell Death, Intracellular ROS Accumulation and Inflammation.

The central nervous system (CNS) is particularly vulnerable to oxidative stress and inflammation, which affect neuronal function and survival. Nowadays, there is great interest in the development of antioxidant and anti-inflammatory compounds extracted from natural products, as potential strategies to reduce the oxidative/inflammatory environment within the CNS and then preserve neuronal integrity and brain function. However, an important limitation of natural antioxidant formulations (mainly polyphenols) is their reduced in vivo bioavailability. The biological compatible delivery system containing polyphenols may serve as a novel compound for these antioxidant formulations. Accordingly, in the present study, we used liposomes as carriers for grape tannins, and we tested their ability to prevent neuronal oxidative stress and inflammation. Cultured catecholaminergic neurons (CAD) were used to establish the potential of lipid-encapsulated grape tannins (TLS) to prevent neuronal oxidative stress and inflammation following an oxidative insult. TLS rescued cell survival after H2O2 treatment (59.4 ± 8.8% vs. 90.4 ± 5.6% H2O2 vs. TLS+ H2O2; p < 0.05) and reduced intracellular ROS levels by ~38% (p < 0.05), despite displaying negligible antioxidant activity in solution. Additionally, TLS treatment dramatically reduced proinflammatory cytokines' mRNA expression after H2O2 treatment (TNF-α: 400.3 ± 1.7 vs. 7.9 ± 1.9-fold; IL-1ß: 423.4 ± 1.3 vs. 12.7 ± 2.6-fold; p < 0.05; H2O2 vs. TLS+ H2O2, respectively), without affecting pro/antioxidant biomarker expression, suggesting that liposomes efficiently delivered tannins inside neurons and promoted cell survival. In conclusion, we propose that lipid-encapsulated grape tannins could be an efficient tool to promote antioxidant/inflammatory cell defense.

Combining edible coatings technology and nanoencapsulation for food application: A brief review with an emphasis on nanoliposomes.

The use of bioactive compounds within the biopolymer-based Edible Coatings (EC) matrices has certain limitations for their application at the food industry level. Encapsulation has been considered as a strategy that enables protecting and improving the physical and chemical characteristics of the compounds; as a result, it extends the shelf life of coated foods. This review discusses recent progress in combining edible coatings with nanoencapsulation technology. We also described and discussed various works, in which nanoliposomes are used as encapsulation systems to prepare, and subsequently apply the edible coatings in plant products and meat products. The use of nanoliposomes for the encapsulation of phenolic compounds and essential oils provides an improvement in the antioxidant and antimicrobial properties of coatings by extending the shelf life of food matrices. However, when liposomes are stored for a long period of time, they may present some degree of instability manifested by an increase in size, polydispersity index, and zeta potential. This is reflected in an aggregation, fusion, and rupture of the vesicles. This investigation can help researchers and industries to select an appropriate and efficient biopolymer to form EC containing nanoencapsulated active compounds. This work also addresses the use of nanoliposomes to create EC extending markedly the shelf life of fruit, reducing the weight loss, and deterioration due to the action of microorganisms.