## 3 Results and Discussion
### Molecular Dynamics Simulation of the Interaction Between Lipid Molecules and Ethanol Molecules
The results of the MMPBSA-binding free energy showed that in the 53% ABV solution, the binding energy between the compound and the ethanol was \(-0.977\) kJ/mol, while in the 53% ABV-peanut lipid system, the binding energy between them decreased to \(-0.742\) kJ/mol. The peanut lipid molecules reduced the binding energy between ethanol and the baijiu flavor substances. At the same time, the binding energy between the lipid molecules and the ethanol molecules was \(-2.18\) kJ/mol. This indicates that there is a strong interaction between the peanut lipid molecules and ethanol, resulting in a weakened retention ability of the ethanol molecules for the compound molecules. Figure 3: (**A**) Motion trajectory section of the ethanol–lipid–aroma compounds system; (**B**) the binding energy of baijiu aroma compounds and lipid; (**C**) the binding energy of ethyl lactate and solvent molecule (ELA is for ethyl lactate); (**D**) the binding energy of heptanoic acid and solvent molecule (HEC is for heptanoic acid); (**E**) the binding energy of ethyl hexanoate and solvent molecule (EHE is for ethyl hexanoate). The interaction energies of three aroma compounds with matrix molecules were calculated. After adding peanut lipid, the binding energies between ethyl lactate and the water and ethanol decreased (with ethanol: \(-0.380\) to \(-0.350\) kJ/mol, with water: \(-0.160\) to \(-0.069\) kJ/mol). The lipid-ethyl lactate binding energy was \(0.632\) kJ/mol. There was no spontaneous interaction between them. In \(53\%\) ABV-lipid solution, heptanoic acid-lipid interaction energy (\(-1.919\) kJ/mol) was greater than that with ethanol (\(-0.639\) kJ/mol). The addition of the lipid slightly reduced the interaction energy of heptanoic acid -ethanol (\(-0.688\) kJ/mol in the \(53\%\) ABV solution). For ethyl hexanoate, its binding energy with the lipid molecule was \(-2.187\) kJ/mol, and the binding energy with the ethanol molecule was \(-0.354\) kJ/mol. Compared with the results in the control group of \(53\%\) ABV, the addition of peanut lipid weakened the binding energy of ethyl hexanoate-ethanol (\(-0.416\) kJ/mol in the \(53\%\) ABV solution). The release intensity of the compound in the solution is the result of the balance of multiple forces. For ethyl hexanoate, the effects of lipid and ethanol effects were partially offset. The lipid in the exogenous food can interacts with both hydrophobic compounds and ethanol molecules, weakening the forces between the ethanol and water molecules- aroma compound molecules, causing \(1+1<2\) effect. The interaction forces between the compound and three peanut lipid acylglycerols were studied, respectively (Table 3). The interaction enthalpy changes between ethyl hexanoate and OOL and OLL was greater than that with POL. The interaction force between heptanoic acid and the three acylglycerols was relatively small, and its interaction force with OLL and POL was slightly greater than that with OOL. OOL is the component with the highest content in peanut acylglycerol, which makes the binding energy between ethyl heptanoate and peanut lipid smaller than that of ethyl hexanoate-peanut lipid. Van der Waals force (or hydrogen bond) is the main interaction force between the baijiu flavor substances and the peanut lipid molecules.