Abstract:This study investigated the quality characteristics of protein bars prepared by protein foam stabilization process （cloudy protein bar，CQB） and a traditional process （ordinary protein bar，CKB）. The color difference （L* value），water activity，texture characteristics，and sensory quality of fresh samples and those stored at room temperature for six months were systematically measured and compared. The results showed that the protein bars produced by the protein foam stabilization process exhibited a brighter color （higher L* value） and a looser texture. During the six-month storage period，the quality deterioration rate of CQB was significantly lower than that of CKB，indicating superior storage stability of the innovative product. Significant differences（P＜0.05） were observed in all physicochemical indicators between the two types of protein bars. Furthermore，microstructural characterization using confocal laser scanning microscopy （CLSM） and scanning electron microscope （SEM） revealed that the CQB generated abundant and uniformly distributed microscopic pores within the protein bar matrix，and this porous structure demonstrated enhanced stability during storage.