网棚栽培砂糖橘糖酸滋味形成的变化

Changes in the Formation of Sweet and Sour Flavours of ‘Shatangju’ (Citrus reticulata Blanco) Cultivated in Net Shed

摘要:

糖酸各组分含量及其所形成的固酸比是砂糖橘果实滋味评价的重要指标。该研究以砂糖橘为试验材料，研究网棚栽培对砂糖橘糖酸滋味成分形成的影响。研究结果表明：网棚栽培方式下12月份的成熟砂糖橘果实的固酸比（TSS/TA）为28.51显著低于露天栽培下的固酸比（31.63，P<0.05）。网棚栽培组中砂糖橘的D-果糖、葡萄糖、D-半乳糖、肌醇、D-山梨醇和海藻糖的生成均被显著抑制（P<0.05），其中D-果糖、葡萄糖含量分别为165.00 mg/g、127.00 mg/g，相比于露天栽培组分别显著降低了7.82%、7.97%；柠檬酸、α-酮戊二酸、苹果酸的含量略低于露天栽培的果实，无显著差异（P>0.05）。固酸比与D-果糖含量正相关性最强（r=0.934**），与柠檬酸含量负相关性最强（r=-0.650**）。网棚栽培方式下，砂糖橘糖组分含量减少、有机酸无显著差异，导致果实滋味偏酸；露天栽培下的砂糖橘清甜可口、酸甜适宜有蜜味，风味的可接受度高于网棚栽培的果实。通过增加网棚的透光性、调控网棚内的温湿度等栽培措施，可更好的保障砂糖橘的品质。

Abstract:

The content of each component of sugar and acid and the formed solid-acid ratio are the important indices for evaluating the taste of ‘Shatangju’ mandarin. In this study, ‘Shatangju’ mandarin (Citrus reticulata Blanco cv. Shatangju) was used as the experimental material to study the effect of the net-shed cultivation on the formation of the sugar and acid flavor components in ‘Shatangju’ mandarin. The results showed that the solid acid ratio (TSS/TA) of mature ‘Shatangju’ mandarin fruit in December under net-shed cultivation was 28.51, which was significantly lower than that under open-air cultivation (31.63, P<0.05). The formation of D-fructose, glucose, D-galactose, inositol, D-sorbitol, and trehalose was significantly inhibited in the net-shed cultivation group (P<0.05). The contents of D-fructose and glucose were 165.00 mg/g and 127.00 mg/g, respectively, which were significantly reduced by 7.82% and 7.97%, compared with the open-air cultivation group. The contents of citric acid, α-ketoglutaric acid, and malic acid were slightly lower than those produced in open-air cultivation, with insignificant difference (P>0.05). The solid-acid ratio had the strongest positive correlation with the D-fructose content (r=0.934**) and the strongest negative correlation with the citric acid content (r=-0.650**). Under the net-shed cultivation, the sugar content of ‘Shatangju’ mandarin decreased with insignificant difference in organic acids, thereby resulting in sour fruit taste. Under the open-air cultivation, the ‘Shatangju’ mandarin was sweet and delicious, exhibiting appropriate sweet and sour tastes with honey flavor. The acceptability of the perceived flavor was higher than that of fruit cultivated in the net shed. The quality of ‘Shatangju’ mandarin can be better ensured through taking measures such as increasing the light transmittance of the net shed, and regulating the temperature and humidity in the net shed.