Northeastern Chinese Sauerkraut Juice as a Water Replacer in Pork Fillings: Flavor Profiles and Sensory Attributes

In this study, the volatile organic compound (VOC) profiles and sensory quality of pork baozi fillings prepared with different substitution levels of Northeastern Chinese sauerkraut juice were characterized using an electronic nose, electronic tongue, gas chromatography–mass spectrometry (GC–MS), and gas chromatography–ion mobility spectrometry (GC–IMS). The results showed that both the VOC profiles and sensory attributes of pork baozi fillings varied significantly across sauerkraut juice substitution levels. A total of 80 and 66 VOCs were identified by GC–MS and GC–IMS, respectively. Notably, pork baozi fillings with the 75% sauerkraut juice substitution level exhibited the highest VOC diversity, the highest total VOC content, and the highest overall sensory score. Compared with the control group (12,348.57 μg/kg), the total VOC content increased significantly by 155% to 31,495.61 μg/kg at 75% substitution. Orthogonal partial least squares discriminant analysis (OPLS–DA) screened out 19 key differential VOCs, including (E,E)-2,4-decadienal, (E)-2-dodecenal, (E)-9-octadecenoic acid ethyl ester, oleic acid and 2,4-hexadienoic acid, ethyl ester. Seventeen fatty acids were quantified, among which (E)-9-octadecenoic acid (C18:1n9t) and palmitic acid (C16:0) accounted for 55.90% and 21.78% of the total fatty acid content, respectively. Partial replacement of water with sauerkraut juice effectively reduced off-flavors in pork baozi fillings and increased the proportion of unsaturated fatty acids, thus improving overall palatability and nutritional quality. This study provides preliminary insights into the flavor modulation mechanism of sauerkraut juice in pork baozi fillings and offers a theoretical basis for the development of high-quality sauerkraut pork products.