Preparation and Physicochemical Characterization of Softgels Cross-Linked with Cactus Mucilage Extracted from Cladodes of Opuntia Ficus-Indica

Abstract

A new crosslinking formulation using gelatin (G) and cactus mucilage (CM) biopolymers was developed, physicochemically characterized and proposed as an alternative wall material to traditional gelatin capsules (softgels). The effect of G concentration at different G/CM ratios (3:1, 1:1 and 1:3) was analyzed. Transparency, moisture content (MC), solubility in water (SW), morphology (scanning electron microscopy, SEM), vibrational characterization (Fourier transform infrared, FTIR), color parameters (CIELab) and thermal (differential scanning calorimetry/thermogravimetric analysis, DSC/TGA) properties of the prepared composite (CMC) capsules were estimated and compared with control (CC) capsules containing only G and glycerol. In addition, the dietary fiber (DF) content was also evaluated. Our results showed that the transparency of composite samples decreased gradually with the presence of CM, the G/CM ratio of 3:1 being suitable to form the softgels. The addition of CM decreased the MC, the SW and the lightness of the capsules. Furthermore, the presence of polysaccharide had significant effects on the morphology and thermal behavior of CMC in contrast to CC. FTIR spectra confirmed the CMC formation by crosslinking between CM and G biopolymers. The addition of CM to the softgels formulation influenced the DF content. Our findings support the feasibility of developing softgels using a formulation of CM and G as wall material with nutritional properties.

Extraction and Physicochemical Characterization of Dried Powder Mucilage from Opuntia ficus-indica Cladodes and Aloe Vera Leaves: A Comparative Study

“…OFI mucilage is also considered a potent antioxidant due to its carbohydrate and polyphenol content [ 15 , 16 ]. Additionally, a high total dietary fiber content, between 57 and 72 g/100 g dry matter, has been reported for OFI mucilage [ 17 , 18 , 19 ].…”

“…This natural hydrocolloid has garnered growing industrial interest due to its edible, biodegradable, non-toxic characteristics, and its cost effectiveness [ 24 ]. Its potential applications in the food, pharmaceutical, and cosmetic industries include its use as thickening, binding, emulsifying, stabilizing, and gelling agent [ 25 ]; film-former [ 26 ]; and as wall material for encapsulation processes [ 18 , 19 , 27 ]. Previous studies have shown that OFI mucilage is considered a rich source in polyunsaturated fatty acid, especially α-linolenic (C18: 3 ω-3) and linoleic (C18: 2 ω-6), which is essential for human nutrition [ 16 ].…”

Encapsulation Effect on the In Vitro Bioaccessibility of Sacha Inchi Oil (Plukenetia volubilis L.) by Soft Capsules Composed of Gelatin and Cactus Mucilage Biopolymers

“…Compared with the free sacha inchi oil [ 40 ], during in vitro digestion, the soft capsules showed a low protection of the encapsulated PUFAs against gastric conditions because of the nature of the wall materials and the G/CM ratio in the matrix. This behavior was associated with the intermolecular interactions between the functional groups of CM combined with G, which gradually disappeared as a result of the repulsion forces of the biopolymers [ 21 , 41 , 42 ], as well as the rapid degradation of the gelatin by the proteolytic enzymes present in the stomach [ 20 ], which reduced the barrier properties of the matrix. This was insufficient at protecting the oil against oxidation, and in turn affected the porosity of the biopolymer matrix and the oil release rate during in vitro digestion.…”

“…The soft capsule design was developed according to the method reported by Camelo et al [ 21 ]. CM (1.0 g) and food grade G (21.0 g) were separately dissolved in 100 mL of distilled water at 18 °C and 40 °C for 2 h and 30 min, respectively.…”

“…An emerging trend in the food industry has recently sought to partially or completely replace G with other non-animal natural hydrocolloids. This has allowed plant mucilage to emerge as an attractive structural biopolymer alternative to soft capsules [ 21 ]. The mucilage extracted from the cladodes of Opuntia ficus-indica is a heteropolysaccharide matrix that has proven to be a suitable natural structuring material in soft capsules because of its high fiber content and desirable functional properties [ 22 , 23 , 24 ].…”