# Optimization and Preparation of Tallow with a Strong Aroma by Mild Oxidation
## 2 Results and Discussion
### SPME-GC-MS Analysis Results of Oxidized Melled Tallow under Different Conditions  
SPME-GC-MS was used for qualitative and quantitative analysis of compounds with aroma characteristics. A total of 51 aroma compounds were detected in tallow melted under different conditions (Tables 2-4). Among them, twenty-nine aroma compounds, including fifteen aldehydes, four alcohols, four acids, three esters, and three heterocyclic compounds were detected in tallow melting at different reaction temperatures. A total of thirty-nine aroma compounds were detected in melted tallow at different reaction times, including seventeen aldehydes, six acids, six ketones, five esters, two alcohols, and three heterocyclic compounds. A total of twenty-nine aroma compounds, including fourteen aldehydes, eight acids, three alcohols, three esters, and one other compound were detected in tallow melting at different air flow rates. Figure 3: The effect of air velocity on AV, PV, and P-AV. Figure 2: The effect of reaction time on AV, PV, and P-AV. \begin{table}
\begin{tabular}{c c c c c c c c c c} \hline \hline \multicolumn{1}{c}{**Different Reaction**} & \multicolumn{1}{c}{**Sample**} & \multicolumn{1}{c}{**Milky**} & \multicolumn{1}{c}{**Muttony**} & \multicolumn{1}{c}{**Animal Fat**} & \multicolumn{1}{c}{**Sweet**} & \multicolumn{1}{c}{**Burnt**} & \multicolumn{1}{c}{**Fruit**} & \multicolumn{1}{c}{**Sour**} & \multicolumn{1}{c}{**Spoiled**} & \multicolumn{1}{c}{**Weighted Total**} \\ \multicolumn{1}{c}{**Conditions**} & \multicolumn{1}{c}{**Number**} & & & & & & & & & & \\ \hline \multirow{8}{*}{Temperature} & \(120\,^{\circ}\)C & 0.6 & 0.34 & 0.64 & 0.48 & 0.2 & 0.12 & \(-0.1\) & \(-0.14\) & 2.14 \\  & \(130\,^{\circ}\)C & 0.72 & 0.3 & 0.72 & 0.48 & 0.2 & 0.12 & \(-0.1\) & \(-0.2\) & 2.24 \\  & \(140\,^{\circ}\)C & 0.78 & 0.34 & 0.8 & 0.48 & 0.2 & 0.12 & \(-0.16\) & \(-0.16\) & 2.4 \\  & \(150\,^{\circ}\)C & 0.94 & 0.24 & 0.68 & 0.58 & 0.1 & 0.24 & \(-0.1\) & \(-0.14\) & 2.54 \\  & \(160\,^{\circ}\)C & 0.64 & 0.34 & 0.9 & 0.48 & 0.24 & 0.12 & \(-0.22\) & \(-0.14\) & 2.36 \\  & \(25\,\min\)m & 0.87 & 0.62 & 0.84 & 0.74 & 0.22 & 0.22 & \(-0.25\) & \(-0.12\) & 3.13 \\  & \(35\,\min\)m & 0.85 & 0.65 & 0.89 & 0.71 & 0.20 & 0.27 & \(-0.22\) & \(-0.06\) & 3.29 \\ Time & \(45\,\min\)m & 0.68 & 0.67 & 0.82 & 0.52 & 0.11 & 0.26 & \(-0.35\) & \(-0.15\) & 2.57 \\  & \(55\,\min\)m & 0.65 & 0.73 & 0.65 & 0.55 & 0.11 & 0.21 & \(-0.45\) & \(-0.16\) & 2.28 \\  & \(65\,\min\)m & 0.55 & 0.78 & 0.58 & 0.46 & 0.15 & 0.25 & \(-0.69\) & \(-0.25\) & 1.83 \\  & \(18\,\mathrm{L/h}\) & 0.72 & 0.56 & 0.76 & 0.90 & 0.24 & 0.22 & \(-0.24\) & \(-0.16\) & 3.00 \\  & \(48\,\mathrm{L/h}\) & 0.90 & 0.52 & 0.80 & 0.72 & 0.24 & 0.22 & \(-0.28\) & \(-0.14\) & 2.98 \\ Air velocity & \(78\,\mathrm{L/h}\) & 0.84 & 0.64 & 0.64 & 0.54 & 0.32 & 0.24 & \(-0.24\) & \(-0.10\) & 2.88 \\  & \(108\,\mathrm{L/h}\) & 0.84 & 0.68 & 0.72 & 0.84 & 0.24 & 0.22 & \(-0.28\) & \(-0.14\) & 3.12 \\  & \(138\,\mathrm{L/h}\) & 0.72 & 0.52 & 0.68 & 0.54 & 0.24 & 0.24 & \(-0.24\) & \(-0.16\) & 1.83 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Sensory score results of oxidized melted tallow under different conditions. \begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline \multicolumn{1}{c}{**Component Information**} & \multicolumn{5}{c}{**Relative Content (ng/g)**\({}^{\tau}\)} \\ \hline
**No.