Psychophysical Effects of Increasing Oil Concentrations on Saltiness and Bitterness Perception of Oil-in-Water Emulsions

Exploring the oral processing mechanisms for saltiness enhancement with NaCl nanocrystals in oleogel systems based on black pepper oleoresin and sunflower seed oil

Reducing salt content in processed foods while maintaining flavor is crucial for human health. This study investigates the sensory interaction between the pungency of black pepper oleoresin and saltiness within an oleogel matrix by incorporating NaCl nanocrystals into a black pepper oleoresin formulated with glyceryl monostearate and soy lecithin (G-L-P). Psychophysical results revealed that the salt content in the G-L-P and G-L systems (G-L-P without black pepper oleoresin) was reduced by up to 66.77 % and 37.08 % compared to the G system (G-L without soy lecithin), respectively. During oral processing, the G-L and G-L-P systems formed oil-in-water emulsions with smaller and more numerous oil droplets. Within 5 s, the Na+ concentration was lowest in the G system (2.2 g/L), while the G-L and G-L-P systems showed higher concentrations (3.1 g/L and 3.0 g/L, respectively). This research provides a theoretical basis for the food industry to develop low-salt products without compromising flavor.

Insight into the enhancement and mechanism of saltiness perception by salty peptides from bovine bone

Food-derived salty peptides have been considered promising substitutes for sodium salt. In this work, three novel salty dipeptides Asp-Pro (DP), Asp-Arg (DR), and Arg-Glu (RE) were identified from bovine bone hydrolysates. The salt reduction rates were 76.85 %, 77.28 %, and 73.72 % by the three peptides (2 mg/mL) in a NaCl concentration of 0.203 g/100 mL, respectively. According to Stevens' law, a non-linear relationship between saltiness intensity and concentration was quantified, showing a slower increase in the sensory intensity perception compared with the changes in physical concentration (β < 1). In molecular detail, electrostatic energy and van der Waals energy were the main energetic contributions to forming stable complexes. The binding of salty peptides to TMC4 was driven by hydrogen bonding and salt bridge, and the main binding sites were Glu319, Ala579, and Thr581. These results could provide new insight into the salt-enhancing property and interaction mechanism of salty peptides as novel sodium substitutes.

Techniques of incorporation of salty compounds, food matrix, and sodium behaviour and its effect over saltiness perception: an overview

The salty taste is usually associated with the positively charged ion sodium present in sodium chloride. Due to its relevance in the food industry, there have been several studies to determine how this ion behaves in various food matrices, or the use of techniques to improve saltiness perception to reduce the amount necessary for savoury food. Several databases were searched, and it was discovered that sodium can interact with the protein, modifying its mobility, as well as, other components of the food matrix, such as fat, that seem to interfere with saltiness perception, increasing or reducing it. Several techniques were used to identify the interaction between sodium and the food matrix, as well as sensory testing to determine the influence of different modification strategies to enhance the saltiness perception. Due to the multiple factors involved in the salty taste, understanding the effect of the technique to modify saltiness perception, the interaction of the matrix components of the food, and the sodium interaction with those components, can be of use in the developing process of foods with a reduction in the sodium content.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13197-023-05861-6.

Saltiness perception in gel-based food systems (gels and emulsion-filled gels)

Reducing salt in food without compromising its quality is a huge challenge. Some review articles have been recently published on saltiness perception in some colloidal systems such as emulsions. However, no published reviews are available on saltiness perceptions of gel-based matrices, even though salt release and perception in these systems have been extensively studied. This article reviews the recent advances in salt perception in gel-based systems and provides a detailed analysis of the main factors affecting salt release. Strategies to enhance saltiness perception in gels and emulsion-filled gels are also reviewed. Saltiness perception can be improved through addition of biopolymers (proteins and polysaccharides) due to their ability to modulate texture and/or to adhere to or penetrate through the mucosal membrane on the tongue to prolong sodium retention. The composition of the product and the distribution of salt within the matrix are the two main factors affecting the perception of salty taste. Food structure re-design can lead to control the level of interaction between the salt and other components and change the structure, which in turn affects the mobility and release of the salt. The change of ingredients/matrix can affect the texture of the product, highlighting the importance of sensory evaluation.

Saltiness enhancement by "má là" umami flavor in NaCl model aqueous and oil-added systems

The health concerns associated with high dietary sodium and the quest for a sensory experience have prompted the need for new strategies that can reduce the salt content of foods and have good acceptability. To investigate the cross-modal interaction effects of "má là" umami flavor (total of eight carriers) on the saltiness perception and effective sodium reduction in low-to-strong NaCl aqueous solutions (0.203 %-1.39 %) and oil-added systems (5 %, 10 %, 15 %, 20 %, 25 % canola oil, wt%), sixteen assessors were selected and two methods including saltiness intensity comparison with a category scale and rating with a generalized Labeled Magnitude Scale (gLMS) were used. The results showed PnSnUn carriers significantly enhance saltiness at moderate-to-strong NaCl solutions, and higher saltiness intensity with the addition of canola oil, especially at 25 % oil level. In addition, based on the developed Stevens' power function the sodium reduction was calculated, it was evident that two "má là" umami flavor combinations (one flavor combination was low "má", low "là" and moderate umami, and the other flavor combination with moderate "má", low "là" and moderate umami) were found to perform best with maximum sodium reduction of 18.88 % and 18 %, respectively, and when incorporating 25 % canola oil, the maximum sodium reduction raised by approximately 10 % (to 28.00 % and 28.42 %). This research not only confirmed the positive modulating effect of the "má là" umami flavor on saltiness perception in NaCl solutions, but also showed that the presence of oil further enhanced this effect. This work offered a new and promising insight into the development of foods with reduced sodium content while maintaining the saltiness properties.

Relationship between sensory saltiness intensity and added oil in low-viscosity and high-viscosity polymer solutions

Generally, the foods we usually eat are not only aqueous solutions, but also viscous solutions and solids. Therefore, it is interesting for us to explore how taste components are perceived in a viscous polymer solution. The relationship between the sensory evaluation of saltiness intensity, amount of added oil, and apparent viscosity was clarified in low-viscosity and high-viscosity polymer solutions. The study was conducted using samples containing corn oil, sodium chloride, and [xanthan gum] or [xanthan gum + locust bean gum] as a thickener. Oil was added to the viscous polymer solutions regardless of whether they were low- or high-viscosity, and saltiness intensity was evaluated as compared with a reference solution. The low-viscous polymer solutions with [xanthan gum] were perceived to be saltier than the high-viscous polymer solutions with [xanthan gum + LBG] as the amount of oil increased. The shear stress value gradually increased as the amount of oil increased in both the low-viscosity and the high-viscosity polymer solutions, as derived from the fluid constitutive equation. There was a correlation between saltiness intensity and apparent viscosity in both high- and low-viscosity polymer solutions. A coefficient of determination (R² ) of 0.918 was obtained between saltiness intensity and "apparent viscosity" for the samples using [xanthan gum] and that of 0.683 between saltiness intensity and "apparent viscosity" for the samples using [xanthan gum+LBG]. The low-viscosity polymer solutions showed a saltier intensity as the amount of oil increased and a greater correlation with apparent viscosity, as compared with the high-viscosity polymer solutions.

Beer and Consumer Response Using Biometrics: Associations Assessment of Beer Compounds and Elicited Emotions

Some chemical compounds, especially alcohol, sugars, and alkaloids such as hordenine, have been reported as elicitors of different emotional responses. This preliminary study was based on six commercial beers selected according to their fermentation type, with two beers of each type (spontaneous, bottom, and top). Chemometry and sensory analysis were performed for all samples to determine relationships and patterns between chemical composition and emotional responses from consumers. The results showed that sweeter samples were associated with higher perceived liking by consumers and positive emotions, which corresponded to spontaneous fermentation beers. There was high correlation (R = 0.91; R² = 0.83) between hordenine and alcohol content. Beers presenting higher concentrations of both, and higher bitterness, were related to negative emotions. Further studies should be conducted, giving more time for emotional response analysis between beer samples, and comparing alcoholic and non-alcoholic beers with similar styles, to separate the effects of alcohol and hordenine. This preliminary study was a first attempt to associate beer compounds with the emotional responses of consumers using non-invasive biometrics.