2.2.2. Preparation of the *Laminaria-Psyllium* Gels

The control sample (Psy) was prepared by adding 4% (*w*/*w*, d.b) *Psyllium* husk (160–315 μm range of particle size) to distilled water at 40 ◦C under mechanical stirring (10 min, 200 rpm) [18]. Another *Psyllium* gel was prepared in a similar manner as the control by using the *Laminaria* autohydrolysis liquid extract (PsyL).

*Laminaria-Psyllium* gels were prepared by mixing (Eurostar Power-b, Ika-Werke, Staufen im Breisgau, Germany) for 5 min/200 rpm at room temperature, the control sample and the alga purée mixture at the ratios 25:75, 50:50, and 75:25 in order to obtain visually different structures with potential different applications. Two batches of 160 g of each gel (*Laminaria-Psyllium*: 25:75, 50:50, 75:25) were prepared, poured into sealed plastic containers (Ø = 10 cm) and stored at 4 ◦C for 24 h to maturate. The schematic procedure of the sample preparation and analysis is presented in Figure 1.

**Figure 1.** General schematic procedure of the gel preparation and analysis (Lo—*Laminaria ochroleuca*; Psy—*Psyllium* gel prepared with water (control); US—ultrasound treatment; PsyL—*Psyllium* gel prepared with autohydrolysis liquor).
