Abstract: Meat meal is one of the most crucial feed ingredients, rich in high-quality animal proteins, fats, minerals, and vitamins. The high nutritional value can also provide the essential amino acids for animal growth and immune function. However, the meat meal is susceptible to environmental and storage factors during processing, transportation, and storage, leading to varying freshness and quality deterioration. The freshness of the meat meal can decline significantly during storage over time, due to microbial activity and enzymatic reactions. Thus, the protein degradation and lipid oxidation can cause nutrient loss. Concurrently, aldehydes, ketones, heterocycles, and acids can accumulate as volatile organic compounds (VOCs), leading to undesirable odors, such as rancidity and putrefaction. Ultimately, there is a low freshness grade of the feed ingredient. This study aims to analyze the VOCs in the meat meal at different freshness levels. A systematic investigation was also made to explore the correlation between freshness indicators and VOCs. The gas sensors were selected to be responsive to the freshness-related VOCs. The pork and chicken meal were selected as the feed ingredients. The national standard was employed to determine the freshness indicators. After that, the headspace solid-phase microextraction combined with gas chromatography-mass spectrometry (HS-SPME-GC-MS) was utilized to detect the VOCs in the meat meal samples with the varying freshness levels. Extraction parameters were optimized using single-factor experiments and the response surface method. The optimal parameters were then determined as follows: fiber type, 50/30 µm DVB/CAR/PDMS; extraction temperature, 80°C; extraction time, 40 min; equilibrium time, 30 min; and desorption time, 5 min. According to the optimal extraction, the 128 and 114 VOCs were identified from the pork and chicken meal, respectively. These VOCs encompassed alcohols, aldehydes, esters, ketones, acids, phenols, hydrocarbons, and heterocycles. Aldehydes and heterocycles were the predominant components. Freshness classification was performed on four freshness indicators (TVB-N, AV, pH, and TVC). Orthogonal partial least squares discriminant analysis (OPLS-DA) was conducted with the relative abundances of 242 VOCs via GC-MS as input variables (X), while freshness classification was used as categorical labels (Y) to establish the OPLS-DA model. The results demonstrated that the robust performance of the prediction was achieved, with R²_X = 0.872, R²_Y = 0.982, and Q² = 0.941 for PM, and R²_X = 0.819, R²_Y = 0.987, and Q² = 0.965 for CM, both meeting Q² > 0.5. Furthermore, the variable importance in the projection (VIP) scores was used to identify the key VOCs influencing meat meal freshness, with the variables of VIP > 1 being considered the most influential. According to this criterion, 38 and 31 VOCs were identified as the key freshness- and quality-related compounds in the pork and chicken meal, respectively, with 10 shared key VOCs: three hydrocarbons (2,6,10-trimethyl tetradecane, heptadecane, and naphthalene), four aldehydes (benzaldehyde, 2-butyl-2-octenal, nonanal, and (Z)-hexadecenal), one acid (hexanoic acid), one ketone (2-decanone), and one alcohol (1-octen-3-ol). Pearson correlation analysis was performed between freshness indicators and VOCs, in order to elucidate the relationship between key VOCs and meat meal freshness. The 25 and 17 VOCs were identified in the pork and chicken meal, respectively, as significantly correlated with the freshness indicators (TVB-N, AV, pH, and TVC). Among them, heptadecane, 1-octen-3-ol, 2-butyl-2-octenal, and (Z)-hexadecenal also shared the characteristic VOCs. 10 gas sensors were chosen potentially responsive to the freshness indicators. These findings can provide a scientific basis for the VOC detection and the freshness of the meat meal using gas sensors.