Synergistic interaction between exogenous and endogenous emulsifiers and its impact on in vitro digestion of lipid in crowded medium.

Control of lipid digestibility by various food components has received great attention in recent decades. However, there is limited literature on investigating the synergistic effect of exogenous emulsifiers and endogenous sodium cholate (SC) on lipid digestion in a simulated physiological crowded medium. In this work, the synergistic interaction of Tween80 and SC according to the regular solution theory, and the hydrolysis of lipid emulsions containing tricaprylin, glyceryltrioleate or soybean oil in crowding medium was studied. The results show that emulsions stabilized by a combination of Tween80 and SC showed higher digestion rate and transformation than those with Tween80 or SC. The digestion rate could be increased by polyethylene glycols (PEGn) with varying crowding degree. The denaturation temperature of the lipase was increased in macromolecular crowded medium. This work allows for better understanding of the interaction between the amphiphiles and the macromolecular crowding effect on lipase digestion in the physiological environment.

The relationship between alkylamide compound content and pungency intensity of Zanthoxylum bungeanum based on sensory evaluation and ultra-performance liquid chromatography-mass spectrometry/ mass spectrometry (UPLC-MS/MS) analysis.

BACKGROUND: Zanthoxylum bungeanum originating in different places varies in alkylamide content and pungency intensity. RESULTS: The pungency intensity of 19 Zanthoxylum bungeanum samples was first determined with Scoville pungency units (SPUs). The SPUs were found to range from 3.80E + 04 to 5.40E + 05. The chemical compositions and contents were measured next, using the ultra-performance liquid chromatography-mass spectrometry/ mass spectrometry (UPLC-MS/MS) method. The total alkylamide content ranged from 9.83 ± 0.15 to 89.98 ± 1.35 g kg-1 . Hydroxy-ϵ-sanshool, hydroxy-α-sanshool, hydroxy-ß-sanshool, hydroxy-γ-sanshool, bungeanool, and isobungeanool were found to be the key pungent compounds, ranging in proportion from 92.65% to 97.69%. The relationship between alkymide compound content and pungency intensity was also analyzed by ridge regression, and it was found that the ß values of independent variables were stable when k was more than 0.6. The regression coefficients of hydroxy-ϵ-sanshool, hydroxy-α-sanshool, hydroxy-ß-sanshool, hydroxy-γ-sanshool, bungeanool, isobungeanool, and other alkylamides were 0.105, 0.177, 0.386, -0.166, -0.006, 0.005, and -0.018, respectively. CONCLUSION: Hydroxy- sanshool compounds were important in determinant the pungency intensity of Z. bungeanum. Knowledge of the relationship between alkymide compound content and pungency intensity will assist in the creation of new methods to determine pungency intensity and provide a scientific basis for flavor design, development of pungent food products, and consumer choice evaluations. © 2018 Society of Chemical Industry.

Influence of carboxymethyl cellulose and sodium alginate on sweetness intensity of Aspartame.

Sensory evaluation of Aspartame in the presence of sodium carboxymethyl cellulose (CMC-L) and sodium alginate (SA) revealed that only CMC-L showed a suppression effect, while SA did not. By using an artificial taste receptor model, we found that the presence of SA or CMC-L resulted in a decrease in association constants. Further investigation of CMC-L solution revealed that the decrease in water mobility and diffusion also contribute to the suppression effect. In the case of SA, the decreased viscosity and comparatively higher amount of free water facilitated the diffusion of sweetener, which might compensate for the decreased binding constant between Aspartame and receptor. This may suppress the impact of SA on sweetness intensity. The results suggest that exploring the binding affinity of taste molecules with the receptor, along with water mobility and diffusion in hydrocolloidal structures, provide sufficient information for understanding the mechanism behind the effect of macromolecular hydrocolloids on taste.

Realization of the reversible vesicle-micelle transition of vitamin-derived bolaamphiphiles by heat change monitoring.

The real-time energetics involved in the structural change of a zwitterionic vitamin-derived bolaamphiphiles (DDO) vesicles, which were induced by conventional surfactants, such as hexadecyltrimethylammonium bromide (CTAB), sodium dodecyl sulfate (SDS), and Triton X-100 (TX100), was characterized by isothermal titration calorimetry (ITC). Interactions of both CTAB and SDS with DDO were accompanied with considerable heat release whereas the interaction energetics between TX-100 and the vesicles were small. However, the transition of DDO vesicles to micelles did occur upon the addition of all of the three surfactants. Fine inflection points were observed in heat flow enthalpograms, which indicated systematically the change of vesicle structure. By monitoring the interaction of CTAB with DDO, we found that heat release kept constant over a certain concentration range at higher temperatures. The repairing effect of heating was revealed and a reversible transition from micelles to vesicles of DDO was thus realized. Further encapsulation of fluorescein in DDO vesicles proved that the reversible vesicle-micelle transition was controllable. This research demonstrates that ITC combined with complementary analytical methods such as dynamic light scattering (DLS) and transmission electron microscopy (TEM) helps to get the real-time information of the structural changes of vesicles. It also shows that these synthetic novel bolaamphiphiles offer great promise for designing controllable release system.