Nesrine Mahfoudhi

BACKGROUND: This study evaluated the extraction, macromolecular characterization, and active packaging application of polysaccharides derived from the red seaweed Gelidium sesquipedale for fresh‐cut apple preservation. RESULTS: Thermo‐alkaline extraction (20 g kg ⁻¹ NaOH, 60 °C), yielded 380 g kg ⁻¹ of an agarose rich galactan fraction. High‐performance liquid chromatography–refractive index detection confirmed high d ‐galactose (684 ± 12 g kg ⁻¹ ) and 3,6‐anhydro‐ l ‐galactose (261 ± 8 g kg ⁻¹ ) contents, validating successful alkali‐induced desulfation down to 5.2 g kg ⁻¹ sulfates. Fourier transform infrared spectroscopy further confirmed the characteristic agarobiose repeating backbone. The formulated active film plasticized with 100 g kg ⁻¹ glycerol exhibited robust mechanical integrity and a favorable water vapor permeability (1.75 × 10 ⁻⁶ g m ⁻¹ s ⁻¹ Pa ⁻¹ ). When evaluated as an active insert liner for the preservation of fresh‐cut apples over 12 days at 4 °C, the film significantly reduced cumulative weight loss (37.6 vs 133.2 g kg ⁻¹ for control) and maintained headspace gas equilibrium. Furthermore, the active packaging effectively inhibited polyphenol oxidase activity by 53.8%, reduced ascorbic acid degradation by 41.2%, and preserved fresh‐cut apple color by retarding enzymatic browning. CONCLUSION: Gelidium sesquipedale galactans demonstrate high performance as a sustainable active packaging matrix, providing an effective, clean‐label strategy to inhibit postharvest enzymatic browning and extend fresh‐cut produce shelf life. © 2026 Society of Chemical Industry.

This study investigated the development and optimization of a bioactive edible film based on almond gum–gelatin matrix incorporated with rosemary essential oil (REO) and plasticized with glycerol, using a Box–Behnken design (BBD). The optimization process proved high reliability with adjusted coefficients of determination ( R ² _adj ) ranging consistently between 0.986 and 0.999 across all studied responses. The optimized formulation (5% almond gum, 2% REO, and 24.8% glycerol) achieved a tensile strength of 29.23 MPa and an antioxidant activity (2,2‐diphenyl‐1‐picrylhydrazyl [DPPH]) of 79.012%. FTIR analysis of the optimized film showed a successful cross‐linking and intermolecular hydrogen bonding between biopolymers and REO, while DSC thermograms proved enhanced thermal stability of the composite matrix. Characterization revealed low opacity and high antimicrobial activity with > 16 mm of inhibition zones against Escherichia coli , Salmonella typhimurium , and Staphylococcus aureus , by the agar disk diffusion method. Applied on refrigerated chicken fillets for 12 days, the active film significantly suppressed microbial proliferation (TAB, Pseudomonas spp, and psychrotrophic bacteria) compared to control samples. It also significantly retarded chemical alteration, maintaining total volatile basic nitrogen (TVB‐N: 25.12 mg/100 g) and thiobarbituric acid reactive substances (TBARS: 0.38 mg malondialdehyde [MDA]/kg) within acceptable limits. These results confirm that the optimized active edible film can be an important transition as an active protection system, delaying microbial proliferation, sensory shelf life, and lipid oxidation of refrigerated poultry meat from 6 days (control) to 12 days.

This study reported the efficiency of almond gum as a novel wall material in complexation with type B gelatin to encapsulate fish oil containing 37% omega-3 fatty acids. Results showed that the obtained microcapsules exhibited an encapsulation efficiency of 70.5% with particle size of 3.2 μm. The oxidative stability of encapsulated and non-encapsulated fish oil, tested in accelerated storage test (60°C, 4 weeks), showed that encapsulated fish oil possessed a significant stability against oxidation. Produced fish oil microcapsules were used to produce fortified yogurt. Yogurt samples were stored for 4 weeks at 4°C. Enriched yogurts showed higher amount of omega-3 fatty acids, where 82% of omega-3 fatty acids was preserved after 4 weeks of storage compared to 67% in yogurt fortified with non-encapsulated fish oil.

In this study, ‘Béjaoui’ Cucurbita maxima seeds variety were exposed to both microwave and roasting prior to oil cold press extraction. In addition, full-fat mayonnaise formula from untreated and treated pumpkin seed oils was prepared and assessed for their physical stabilities and bioactive properties in 28-day storage at 25 ± 1 °C. A mayonnaise sample prepared with unrefined sunflower seed oil served as a control. The results showed that the microwave pretreatment of seeds greatly enhanced the oxidative stability of the pumpkin seed oil, which increased from 3 h 46 min ± 10 min in the untreated sample to 4 h 32 min ± 14 min in the microwave cold press pumpkin seed oil. The sterol content increased from 4735 ± 236.75 mg/kg oil in the untreated cold press pumpkin seed oil to 5989 ± 299.45 mg/kg oil and 7156 ± 357.8 mg/kg in the microwave cold press pumpkin seed oil and the roasted cold press pumpkin seed oil, respectively. The mayonnaise prepared with microwave cold press pumpkin seed oil exhibited the lowest creaming index and was more stable to droplet growth when compared to the other mayonnaise samples. All mayonnaise samples prepared with pumpkin seed oils exhibited higher total phenolic contents and antioxidant activities during storage when compared to the mayonnaise sample prepared with unrefined sunflower seed oil. Among pumpkin seed oil mayonnaise samples, the highest values were, however, observed in the one prepared with microwave cold press pumpkin seed oil. Thanks to its high nutraceuticals, the latter could be confidently regarded as a natural fat substitute for commercial stable vegetable oils mayonnaise type emulsions.

Almond gum contains an arabinogalactan-type polysaccharide, which plays an important role in defining its interfacial and rheological properties. In this study, rheological and interfacial properties of almond gum and gum arabic aqueous dispersions were comparatively investigated. The interfacial tension of almond gum and gum arabic aqueous dispersions was measured using the pendant drop method in hexadecane. The asymptotic interfacial tension values for almond gum were significantly lower than the corresponding values measured for gum arabic, especially at high concentration. Rheological properties were characterized by steady and oscillatory tests using a coaxial geometry. Almond gum flow curves exhibited a shear thinning non-Newtonian behavior with a tendency to a Newtonian plateau at low shear rate, while gum arabic flow curves exhibited such behavior only at high shear rate. The influence of temperature (5–50 ℃) on the flow curves was studied at 4% (m/m) gum concentration and the Newtonian viscosities at infinite and at zero shear rate, for gum arabic and almond gum, respectively, were accurately fitted by an Arrhenius-type equation. The dynamic properties of the two gum dispersions were also studied. Both gum dispersions exhibited viscoelastic properties, with the viscous component being predominant in a wider range of concentrations for almond gum, while for gum arabic the elastic component being higher than the elastic one especially at higher concentrations. The rheological and interfacial tension properties of almond gum suggest that it may represent a possible substitute of gum arabic in different food applications.

The aim of this study was to evaluate the ability of almond gum, as a novel polymer, to encapsulate β-carotene by spray drying, in comparison with gum arabic. Encapsulation efficiency (EE) was around 66% and 70% using almond gum and gum arabic, respectively, and the reconstituted emulsions had relatively higher particle sizes than the fresh emulsions. A 60-day storage period at 25°C was carried out to investigate the effect of relative humidity (RH) on the kinetic degradation and on the decrease of the color of β-carotene powders. Results showed that β-carotene and color degradations were found to fit well with a first-order kinetic model. Degradation rates increased as RH increased, until a value at which the samples become sticky and collapsed (80% RH) when the degradation rate decreased. These results could prove that collapse phenomena were responsible for the decrease of the degradation rate by decreasing the diffusion of oxygen throughout the wall materials.

The use of coatings is a technique used to increase postharvest life of the fruit. Almond gum exudate was used, in comparison with gum arabic, at concentrations of 10% as a novel edible coating, to preserve the quality parameters of tomato (Solanumlycopersicum). Fruits were harvested at the mature-green stage of ripening. Results showed that the coatings delayed significantly (p < 0.05) the changes in color, weight loss, firmness, titratable acidity, ascorbic acid content, soluble solids concentration, and decay percentage compared to uncoated control fruits. Sensory evaluation proved the efficacy of 10% almond gum and gum arabic coatings to maintain the overall quality of tomato fruits during storage period (20 days). In addition, the difference between gum arabic and almond gum coatings was not significant (p > 0.05) except for pulp color. Therefore, we can suggest the use of almond gum exudate as a novel edible coating extends the shelf-life of tomato fruits on postharvest.

The physicochemical components and functional properties of the gum exudates from the trunk of the almond tree (Prunus dulcis) have been investigated, along with the emulsification and foaming properties. The gum exudates are composed on dry weight basis by 2.45% of proteins, 0.85% of fats and 92.36% of carbohydrates. The latter consist of arabinose, xylitol, galactose and uronic acid (46.8 : 10.9 : 35.5 : 6.0 mass ratio) with traces of rhamnose, mannose and glucose. Moreover, gum exudates are rich in minerals, such as sodium, potassium, magnesium, calcium and iron. The emulsifying capacity was studied for a 20% w/w olive oil in water emulsion as a function of gum concentration (from 3% to 12% w/w in the aqueous phase) as well as pH levels (from 3.0 to 10.0). The most stable and homogeneous emulsion was prepared with an 8% w/w aqueous almond gum solution at a pH between 5.0 and 8.0. In particular, for the same formulation, the emulsion processed by high pressure homogenization (5 passes at 200 MPa) resulted to be extremely stable under accelerated ageing, exhibiting no significant change in droplet size distribution for 14 days at 55 °C. All the tested systems exhibited an extremely low foaming capacity.