This study compared the physicochemical properties and sensory quality of fresh lotus seeds of ‘Mantianxing’ and ‘No.36 space lotus’. The results showed that along with the maturation of seeds, the seed shell color changed from green to brown and that of the plumule turned from yellow to green. In addition, the moisture content decreased, the hardness significantly increased, and the plumpness remained constant. The above changes occurred 4 days earlier in August than in September. During maturation, the total phenol content and DPPH free radical scavenging capacity decreased; the soluble sugar content and sweet taste first increased and then decreased; and the alkaloid content and bitter taste showed an overall increasing trend. Hence, the quality of fresh lotus seeds is determined by the harvesting time, and lotus seeds harvested on day 14 in August and day 18 in September have the highest fresh quality.

中文翻译：

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采收时间对鲜莲子化学成分和品质的影响

本研究比较了'漫天行'和'36号空莲'新鲜莲子的理化性质和感官品质。结果表明，随着种子的成熟，种子壳颜色由绿色变为褐色，胚芽由黄色变为绿色。此外，水分含量降低，硬度显着增加，丰满度保持不变。上述变化发生在8月比9月提前4天。成熟过程中，总酚含量和DPPH自由基清除能力下降；可溶性糖含量和甜味先升高后降低；生物碱含量和苦味总体呈上升趋势。因此，新鲜莲子的品质取决于收获的时间，