石硖龙眼果实成熟特性研究

对石硖龙眼果实成熟期间内外表观性状、重量、大小、可食率、营养品质、果形指数等指标的变化规律进行分析,结果表明:随着果实成熟度的增加,果实的内外表观性状发生了明显变化;重量、大小和可食率呈逐渐增加趋势;营养品质指标可溶性固形物、蔗糖、全糖、Vc含量随成熟期的延长呈上升趋势,但后期稍有下降,而还原糖呈持续缓慢上升趋势,可滴定酸含量在果实成熟期间变化不大;果形指数与核果比逐渐下降,皮果比与皮核比的变化以果实进入完全成熟期为转折点,先下降后上升;内果皮褐变在果实完熟以后明显增加.研究表明,果实可溶性固形物含量、果皮厚度、比熟度、皮果比的变化规律与果实成熟后"退糖"特性较为一致,以比熟度结合花后天数和果实外观变化特征可以较为准确地判断石硖龙眼果实的成熟度.

Studies on the characteristics of longan fruits (cv. Shixia) during maturation

The changes of apparent characteristics,mass,size,edible ratio,qualitity and fruit-shaped index during the period of longan fruits maturating on the tree were all studied.The results showed that with the fruit maturity,the apparent characteristics of fruits changed obviously from the inside to outside.The weight,size,edible ratio tended to increase,the nutrition quality indexes including the total soluble sugars(TSS),sucrose,total sugar,and vitamine C contents arised and declined a little at the last stage of maturaring.While reductant sugar content arised slowly and steadly all the time,there was nearly no change in the content of total titratable acid.The relative indexes including fruit-shaped index and stone/fruit ratio tended to decrease,pericarp/stone and pericarp/fruit ratio first arised and then declined when fruits ripening as a turning point.The endocarp browned obviously when fruit over-ripening.The changes of TSS content,pericarp thickniss,relative maturity and pericarp/fruit ratio were all consistent with the characteristic of "sugar receding"when fruit ripening.We can judge the fruit maturity more exactly by combining the relative maturity with the days from anthesis and the apparent characteristics during fruit maturating.