Search Results (7)

The objective of this study was to investigate the physicochemical properties, drug release and in situ depot-forming behavior of alginate hydrogel containing poorly water-soluble aripiprazole (ARP) for achieving free-flowing injectability, clinically accessible gelation time and sustained drug release. The balanced ratio of pyridoxal phosphate (PLP) and glucono-delta-lactone (GDL) was crucial to modulate gelation time of the alginate solution in the presence of calcium carbonate. Our results demonstrated that the sol state alginate hydrogel before gelation was free-flowing, stable and readily injectable using a small 23 G needle. In addition, the ratio (w/w) of PLP and GDL altered the gelation time, which was longer as the PLP content increased but shorter as the GDL content increased. The alginate hydrogel with a ratio of PLP to GDL of 15:9 had the optimal physicochemical properties in terms of a clinically acceptable gelation time (9.1 min), in situ-depot formation with muscle-mimicking stiffness (3.55 kPa) and sustained release over a two-week period. The alginate hydrogel, which is tunable by varying the ratio of PLP and GDL, could provide a controllable pharmaceutical preparation to meet the need for long-acting performance of antipsychotic drugs like ARP. Full article

Micellar calcium phosphate (MCP) plays an important role in maintaining the structure and stability of the casein micelle and its properties during processing. The objective of this study was to investigate how heating (10 min at 80 or 90 °C) at different pH levels (6.3, 6.6, 6.9, or 7.2) impacted the acid-induced gelation of MCP-adjusted milk, containing 67 (MCP₆₇), 100 (MCP₁₀₀), or 113 (MCP₁₁₃) % of the original MCP content. The unheated sample MCP₁₀₀ at pH 6.6 was considered the control. pH acidification to pH 4.5 at 30 °C was achieved with glucono delta-lactone while monitoring viscoelastic behaviour by small-amplitude oscillatory rheology. The partitioning of calcium and proteins between colloidal and soluble phases was also examined. In MCP-depleted skim milk samples, the concentrations of non-sedimentable caseins and whey proteins were higher compared to the control and MCP-enriched skim milk samples. The influence of MCP adjustment on gelation was dependent on pH. Acid gels from sample MCP₆₇ exhibited the highest storage modulus (G′). At other pH levels, MCP₁₀₀ resulted in the greatest G′. The pH of MCP-adjusted skim milk also impacted the gel properties after heating. Overall, this study highlights the substantial impact of MCP content on the acid gelation of milk, with a pronounced dependency of the MCP adjustment effect on pH variations. Full article

The properties of faba bean (Vicia faba L.) protein isolate (FPI) gels depend on their starting protein material and can be modulated by the addition of polysaccharides. In order to investigate the interplay between these two factors, commercial FPI (FPI₁) and FPI prepared in-house (FPI₂) were used to fabricate glucono-delta-lactone-induced gels, with or without dextran (DX) addition. FPI₁ exhibited lower solubility in water and a larger mean particle size, likely because it experienced extensive degradation due to the intense conditions involved in its preparation. The FPI₁ gel showed a similar water-holding capacity as the FPI₂ gel; however, its hardness was lower and viscoelasticity was higher. After DX addition, the hardness of both FPI gels decreased, while their water-holding capacity increased. Interestingly, DX addition decreased the viscoelasticity of the FPI₁ gel but enhanced the viscoelasticity of the FPI₂ gel. The microstructural analysis demonstrated that the density of the aggregation network decreased in the FPI₁ gel after DX addition but increased in the FPI₂ gel. This was consistent with the changes observed in the dominant protein interaction forces in these gels after DX addition. Overall, these findings have the potential to guide ingredient selection for the tailored preparation of FPI gels. Full article

In this study, glucono-delta-lactone (GDL), which is Generally Recognized as Safe (GRAS), was added to native starches to modify their physicochemical properties. The effects of GDL on the molecular weight, pasting properties, flow behavior, gel syneresis, and crystallization properties of potato, tapioca, and corn starches were investigated. GPC results showed that as the GDL concentration increased, the molecular weight of amylose increased, whereas that of amylopectin decreased. An analysis using the Rapid Visco Analyzer revealed that the addition of GDL improved the pasting properties of potato starch, with reduced peak viscosity and breakdown viscosity, and it also improved setback viscosity. On the other hand, tapioca starch degraded substantially after GDL addition, indicating a lower tendency for short-term retrogradation, as reflected in the lower setback viscosity. The effects of GDL on corn starch pasting properties were very similar to those observed for tapioca starch, but the changes were relatively subtle. In terms of flow behavior, GDL addition decreased and increased the flow index values of the potato and tapioca starch pastes, respectively. However, the effect of GDL addition on the flow index value of the corn starch paste was found to be insignificant. The results also showed that the percentage of syneresis under the influence of GDL depended on the starch botanical origin—that is, potato starch, 14–18%, tapioca starch, 10–13%, and corn starch, 17–20%—which was substantiated by crystallinity analysis. It was observed that GDL has the potential to be used for starch modification because it creates desirable functionalities with the advantage of being a green-labelled ingredient. Full article

The influence of ethanol (0–10%, v/v) on the acid-induced flocculation of casein micelles was examined using diffusing wave spectroscopy. For this purpose, samples containing 10% (w/w) reconstituted skim milk powder and 0–10% (v/v) ethanol were acidified with glucono-delta-lactone and acid-induced coagulation was monitored by diffusing wave spectroscopy. The pH at which acid-induced flocculation of the casein micelles commenced (pH_f) increased near-linearly with increasing ethanol content, whereas the rate of flocculation was not affected by ethanol. The results are discussed in terms of the steric stabilisation of casein micelles by a polyelectrolyte brush in a medium of high ionic strength. Ethanol-induced increases in pH_f are probably primarily due to an ethanol-induced reduction in solvent quality; an ethanol-induced reduction in dissociation of carboxylic acid groups in the brush is likely to contribute. Full article

The production of dry-fermented sausages currently presents several challenges to be addressed: nutrition, health, sensory traits and technology are among the main issues that concern consumers and the meat industry. The objective of this study was to evaluate the effect of different reducing agents commonly used in the manufacture of dry-fermented sausages (salchichon type) with low fat content on the technological characteristics of the product. Four different reducing agents (ascorbic acid, a starter culture, sodium ascorbate and glucono-delta-lactone) were added to the meat batter to assess their impact on the physico-chemical traits, instrumental color, residual nitrates and nitrites and lipid oxidation of this meat product. High nitrate values were observed during both ripening and storage periods. All batches presented lipid oxidation values below the threshold that indicates meat rancidity. Adjustments of the original lean:fat proportion must be carried out on this low fat content sausage to obtain profitable results. Starter culture and sodium ascorbate have shown the best reducing and antioxidant activities among the additives studied. Once we have the technical design of the product, the next step will be oriented to identify the sensory characteristics in order to find a gap in the market. Full article

In this study, the effect of trisodium citrate on the textural properties and microstructure of acid-induced, transglutaminase-treated micellar casein gels was investigated. Various concentrations of trisodium citrate (0 mmol/L, 10 mmol/L, 20 mmol/L, and 30 mmol/L) were added to micellar casein dispersions. After being treated with microbial transglutaminase (mTGase), all dispersions were acidified with 1.3% (w/v) gluconodelta-lactone (GDL) to pH 4.4–4.6. As the concentration of trisodium citrate increased from 0 mmol/L to 30 mmol/L, the firmness and water-holding capacity increased significantly. The final storage modulus (G′) of casein gels was positively related to the concentration of trisodium citrate prior to mTGase treatment of micellar casein dispersions. Cryo-scanning electron microscopy images indicated that more interconnected networks and smaller pores were present in the gels with higher concentrations of trisodium citrate. Overall, when micellar casein dispersions are treated with trisodium citrate prior to mTGase crosslinking, the resulted acid-induced gels are firmer and the syneresis is reduced. Full article