The Effect of Pasteurization and Shelf Life on the Physicochemical, Microbiological, Antioxidant, and Sensory Properties of Rose Apple Cider during Cold Storage

Abstract

Rose apple fruits (Syzygium agueum Alston cv. Taaptimjan) were used to produce cider to overcome their limitation of short shelf life. Following fermentation, alternative pasteurization conditions at 63 °C for 15 s and at 71 °C for 6 s were compared. The effects of pasteurization conditions on physicochemical properties, microbial safety, antioxidant capacity, and sensory properties of the cider were investigated during storage for 6 months at refrigerated temperature. The unpasteurized cider had 5.9% ethanol content with TSS of 4.1 °Brix. Alcohol content of this treatment group increased while TSS decreased during storage, as effects of continuing fermentation. Pasteurization at 63 or 71 °C effectively prolonged cider shelf life to 3 and 6 months, respectively. Nonetheless, the processing significantly decreased contents of ascorbic acid and antioxidants and affected sensory profile of the cider. Principal component analysis (PCA) indicated storage time as the dominant factor determining cider quality. Trained panelists in the sensory study perceived more intense sweetness, less sourness, and less flavor in the pasteurized samples compared to the control group. The pasteurization conditions 71 °C for 6 s achieved microbiological safety and resulted in desirable sensory quality for up to 6 months of shelf life.

Keywords

• cider
• rose apple
• pasteurization
• antioxidants
• sensory profile