Chemical and flavour changes in jackfruit (Artocarpus heterophyllus Lam.) cultivar J3 during ripening

Chemical composition (titratable acidity, moisture content, crude fibre, colour, pH, soluble solids, sugars, organic acids) and flavour changes during ripening of jackfruit (Artocarpus heterophyllus L.) cultivar J3 were evaluated. Significant (p < 0.05) changes in titratable acidity and colour was obtained, but no significant changes were found in moisture and crude fiber contents during ripening. Total soluble solids and total sugars increased significantly (p < 0.05) throughout the ripening process. Total soluble solids at the top portion of the fruit were significantly (p < 0.05) higher than middle and bottom portions of the same fruit. A high content of malic acid was found in unripe fruit (day 1). In contrast, ripened fruit (days 5 and 6) contained a high amount of citric acid. Overall, the total amount of organic acids was found to decrease from the early to later stage of ripening. A total of 23 volatile compounds were tentatively identified by GC and GC–MS. The number of peaks was observed to increase throughout the ripening process. In this study, data obtained suggest that the ripening process of jackfruit was at its optimum at day 5 after harvest.     

菠萝蜜研究进展

菠萝蜜是一种集鲜果食用、药用、林木为一身的优良果树,就近10年来对菠萝蜜价值的研究、种质资源的起源、分类与保存、生物学特性,以及栽培生理、引种和品种选育、育苗技术、病虫害防治、采后保鲜和储藏加工等方面的研究做了系统的综述,并就今后菠萝蜜研究的重点提出建议,认为应重视种质资源收集、保存,和品种选育以及栽培技术的研究。     

雷州半岛菠萝蜜种质遗传多样性的RAPD分析

 用RAPD标记方法对我国雷州半岛的65份菠萝蜜(Artocarpus heterophyllus Lam. ) 实生种质资源DNA的遗传多样性进行了检测, 16个引物共检测到78条带, 其中69条具多态性(占88.4% ) 。聚类分析表明, 65份菠萝蜜材料在遗传距离0.26处可分为3大类。供试种质虽具有丰富的形态性状变异, 但在DNA水平上平均相似性系数为0.7341。干、湿胞类型及引自马来西亚的种质均不能独立聚类。对菠萝蜜品种的干、湿胞分类法及菠萝蜜品种的引种区域进行了讨论。     

菠萝蜜素背肘隆螽生物学习性及防治

研究了菠萝蜜上新发现的重要害虫素背肘隆螽的生物学习性.该虫在海南每年发生2代,以若虫或成虫越冬.6月中旬～7月下旬、10月下旬～12月上旬是为害高峰期.笔者详细描述素背肘隆螽的形态特征、取食与为害、活动与栖息、蜕皮与羽化、交尾与产卵等习性,并提出剪除着卵枝条和人工捕杀等防治方法,为今后生产上防治素背肘隆螽提供参考依据.     

菠萝蜜果实成熟过程中香气成分组成及变化规律研究

以不同成熟阶段的菠萝蜜果实为材料,采用顶空-固相微萃取与气相色谱-质谱联用技术,对菠萝蜜果实成熟过程中的香气成分及变化规律进行研究,以期为菠萝蜜果实采收、贮运与保鲜技术提供参考依据。结果表明：菠萝蜜果实成熟过程的4个阶段共鉴定出51种化合物,包括酯类26种、烃类17种,其中,异戊酸乙酯、乙酸异戊酯、异戊酸异戊酯和3-甲基丁酸-2-甲基丁酯是构成成熟菠萝蜜香气的主要成分,异戊酸乙酯是鉴定III阶段（9成熟）菠萝蜜的标志性化合物。在菠萝蜜不同成熟阶段,香气物质种类及含量存在明显差异。α-香柠檬烯、β-倍半水芹烯、3-蒈烯、左旋-β-蒎烯等烃类仅出现在Ⅰ、Ⅱ阶段（7成熟、8成熟）,而异戊酸丙酯、异戊酸异戊酯、3-甲基丁酸-2-甲基丁酯等酯类仅出现在Ⅲ、Ⅳ阶段（9成熟、完全成熟）。且异戊酸乙酯的相对含量呈现先升高后降低的趋势,乙酸异戊酯、β-石竹烯、异戊酸异戊酯、3-甲基丁酸-2-甲基丁酯相对含量呈现持续升高的趋势,而异戊酸甲酯呈现逐渐下降趋势。     

广东湛江地区木菠萝种质资源果实的品质分析

以广东省湛江地区22份木菠萝种质为试材,进行了果实品质分析测定。结果表明,H16的可溶性蛋白质含量（5.04%）和总糖含量（28.18%）最高,极显著地高于其他株系,维生素C含量（7.39 mg.（100 g）-1）也属高水平;H14的氨基酸含量（9.20%）和可溶性固形物含量（27.38%）最高,极显著地高于其他株系;H13的有机酸含量（0.06%）和维生素C含量（3.11 mg.（100 g）-1）均属偏低水平;H2的氨基酸含量（0.38%）最低,极显著地低于其他株系。综合各项指标得出,H16和H14属于果实品质较好的株系,可在湛江地区推广种植;H13、H3、H2和H9属于果实品质较差的株系。     

ALA对菠萝蜜树光合生理的影响

以定植后2 年菠萝蜜树为试验材料,分别用不同浓度ALA喷施叶面后用LI-6400 便携式光合系统分析仪测定相关光合参数,以研究外源5-氨基乙酰丙酸对菠萝蜜光合作用的影响。结果表明,低浓度ALA可显著促进菠萝蜜树的光合作用,各处理浓度中,以10 mg/L 处理效果最佳,该处理Pn、Tr、WUE、Gs、Ci 比CK 分别提高了56.0%、30.6%、19.4%、23.8%、54.2%,Ls 降低了37.6%,均达到极显著差异水平。浓度高达20 mg/L 时,其Pn、Tr、Gs、Ci 比CK分别降低了2.2%、28.4%、31.1%、11.6%,WUE、Ls 升高 了36.3%、8.1%。由此可见,适宜浓度ALA可以有效促进菠萝蜜的光合效能,浓度过高反而产生抑制作用。     

SPME-GCMS integrated with chemometrics as a rapid non-destructive method for predicting microbial quality of minimally processed jackfruit (Artocarpus heterophyllus) bulbs

SPME-GCMS in combination with chemometrics was employed to correlate volatile headspace composition with microbial quality of minimally processed jackfruit (Artocarpus heterophyllus) bulbs stored at 4 °C and 10 °C. Predictive models of the total viable count (TVC) and yeast and mold count (Y&M) were prepared by Partial Least Square Regression (PLS-R) using total ion current (TIC) and total mass spectral data as independent variables. All PLS-R models correlating microbial quality with GC spectral data and total mass spectral data demonstrated high regression coefficient (R > 0.93). Models generated using TIC performed better in comparison with models prepared with total mass spectral data against test data. Ethanol, ethyl acetate and 3-methyl-1-butanol were identified as major compounds responsible for the observed correlations. The possibility of using GCMS as a nondestructive method for rapid assessment of microbial quality of minimally processed fruits is demonstrated here for the first time.     

不同提取方法对菠萝蜜种子淀粉性质的影响

本实验采用湿磨法、酶法、表面活性剂法、碱法4种方法提取菠萝蜜种子淀粉,研究不同提取方法对菠萝蜜种子淀粉性质的影响。结果表明:湿磨法(SMF)、碱法(氢氧化钠和硫代硫酸钠)、酶法(P7、PBS、ANP、SDN、PBL、P6)、表面活性剂法的提取率分别为18.92%、64.46%、63.82%、55.30%、66.68%、43.57%、46.89%、52.48%、41.03%、70.55%;淀粉膨胀力和溶解性随着温度升高而升高;溶解度和膨胀力均显示湿磨法最高。以淀粉提取率为指标,确定中性蛋白酶(Protex-7L)法为菠萝蜜种子淀粉提取的方法。     

中国菠萝蜜产业发展现状及对策

从产销、种质资源、繁育技术、栽培管理、产品加工和信息流通服务等6方面系统分析中国菠萝蜜产业现状，并对产业前景进行探讨，针对性提出发展对策，以期为广大菠萝蜜科研、生产工作者提供参考。