Investigating Flavor Enhancement Methods in NaCl-Reduced Chinese Bacon (Larou) by Focusing on Physicochemical Characteristics, Bacterial Diversity, and Volatiles

The higher NaCl concentration of Chinese bacon, which features a unique flavor, is a major restriction to consumption. Investigating the role of NaCl in Chinese bacon (<i>Larou</i>) would be beneficial to optimize the dosage and enhance flavor. This study was conducted to categorize <i>Larou</i> by comparing the quality of <i>Larou</i> cured with different concentrations of NaCl and then to investigate the methods of flavor enhancement of NaCl-reduced <i>Larou</i>. The results showed that, based on the differences in quality, <i>Larou</i> were categorized into three types, including the low-NaCl type (<4%, LT), the medium-NaCl type (4-8%, MT), and the high-NaCl type (>8%, HT). The vital physicochemical characteristics (PCs), predominant bacteria, and key volatile compounds (VOCs) were different for each type of <i>Larou</i>. The PCs contributing to the regulation of VOCs were total volatile basic nitrogen (TVB-N) and pH in LT, thiobarbituric acid reactive substance assay (TBARS) in MT, NaNO_2, and moisture content in HT. <i>Lactococcus</i> or <i>Lactobacillus</i>, <i>Staphylococcus</i>, and <i>Kocuria</i> were flavor-producing bacteria in LT, MT, and HT, respectively. Vital PCs and predominant bacteria were associated with several key aldehydes, alcohols, and esters in <i>Larou</i>. Increasing the TVB-N, TBARS, and moisture content, decreasing the pH and NaNO₂ properly, and inoculating with <i>Staphylococcus</i> and <i>Kocuria</i> were effective methods to enhance the flavor of LT. Vital PCs and predominant bacteria are prioritized to meet most of the quality and the biosafety, although key VOCs may be sacrificed at this point.