Abstract:

The purpose of this study was to measure the glass transition temperature (Tg) of Chinese bayberry (Myrica rubra Sieb. & Zucc. cv. Dongkui) and to use the temperature to freeze Chinese bayberry for preservation purpose in practice. It was found that the starting point of partial glass transition temperature (Tg') of Chinese bayberry was －44 ℃, the midpoint －42 ℃ and the termination point －39.2 ℃. Compared with －18 ℃, the storage temperature of －40 ℃ (simulated glass transition preservation) reduced the post-thawing juice loss and maintained a higher soluble solids content (SSC); no significant differences in pH and titratable acid content, however, were observed between Chinese bayberries stored at both the temperature. Instrumental analysis and sensory evaluation both showed that －40 ℃ was more conducive to maintaining the texture quality of Chinese bayberry.

Key words: Chinese bayberry, glass transition, preservation, quality