Characterization of the sodium binding state in several food products by²³Na nuclear magnetic resonance spectroscopy

Abstract

In food, salt has several key roles including conservative and food perception.For this latter, it is well-known that the interaction of sodium with the food matrix modifies the consumer perception. It is then critical to characterize these interactions in various real foods. For this purpose, we exploited the information obtained on both single and double quantum 23 Na nuclear magnetic resonance (NMR) spectroscopies. All salted food samples studied showed strong interactions with the food matrix leading to quadrupolar interactions. However, for some of them, the single quantum analysis did not match the theoretical prediction. This was explained by the presence of another type of sodium population, which did not produce quadrupolar interactions. This finding is of critical importance to perform quantitative magnetic resonance imaging (MRI) and to understand the consumer salty taste perception.

Quantitative sodium magnetic resonance imaging in food: Addressing sensitivity issues using single quantum chemical shift imaging at high field

“…This relaxation analysis is not discussed here as it requires specific nuclear magnetic resonance (NMR) spectroscopic approaches. For more detailed information, it is possible to refer to the complementary work carried out by our group in El Sabbagh et al [ 38 ]…”

“…This relaxation analysis is not discussed here as it requires specific nuclear magnetic resonance (NMR) spectroscopic approaches. For more detailed information, it is possible to refer to the complementary work carried out by our group in El Sabbagh et al [38] The value of short TE approaches for mapping sodium cannot be overlooked as they guarantee the visibility of sodium in its entirety. It should be noted that the TE obtained is short, although never zero.…”

Multiple quantum filtered nuclear magnetic resonance of 23Na+ in uniformly stretched and compressed hydrogels

“… 25 Alternatively, it is often the case in biological media that the three nuclear transition frequencies of 23 Na + are (nearly) degenerate. 26 Under such circumstances, Hz and evolves only under the influence of quadrupolar relaxation: 27 …”

“…The functional forms of these derived analytical expressions were examined under various motional regimes reported in the literature. 26–28 Figures 1(a) and 1(b) show calculations with analytical expressions h 11 ( t ), h 12 ( t ), and h 13 ( t ) in Eqs. (19) , (22) , and (24) , respectively, in the extreme narrowing limit with a short rotational correlation time of τ C = 1.5 × 10 −10 s and an RQC of (a) Hz and (b) Hz.…”