桃李果实风味物质的研究进展

在论述近年来国内外桃李果实风味物质研究的基础上,从代谢组学角度对国内外风味物质的相关研究进展进行述评,并对桃李果实贮藏过程中风味物质变化进行了综述。     

巴河莲藕罐装生产工艺的研究

[目的]研究特色巴河藕罐头的制作工序和制作方法。[方法]以巴河藕为原料,研究单因素多水平、多因素多水平正交试验,得出适宜的巴河藕罐头最佳热烫条件。[结果]热烫工艺中以95℃的热烫温度,2∶1的液固比,热烫5 min,可达到最佳热烫效果,使酶失活从而保证藕片的品质。[结论]该试验能够改进传统产品的生产工艺,促进莲藕加工业实现产业化发展。     

贡柑果实采后可溶性糖代谢和风味品质变化的关系

研究德庆贡柑常温贮藏条件下果实蔗糖、葡萄糖和果糖等可溶性糖类含量、可溶性固形物含量、酸性转化酶活性等变化及其与风味品质变化的关系,探求贡柑果实风味品质变化的生理机制。结果表明,贡柑果实在贮藏后6~12 d先后出现可溶性固形物(TSS)、可滴定酸含量和酸性转化酶活性的增加,果实的风味品质则同期呈现变淡和出现异味等非正向变化;蔗糖等可溶性糖含量变化呈S型变化模式,其峰位的变化与TSS含量增加呈逆向变化关系,但和风味品质变甜变淡趋势相同。2,4-D处理贡柑后可显著增加好蒂率和好果率,可阻止果实异味产生,但不能延缓可溶性糖含量下降和果实风味品质变淡,蔗糖等可溶性糖含量变化没有呈现S型变化特征。     

干海带中挥发性风味成分的分析与鉴定

为了鉴定干海带的挥发性风味品质,采用固相微萃取法(SPME)提取干海带的挥发性风味成分,利用气相色谱-质谱联用(GC-MS)对海带干品中挥发性风味成分进行分离鉴定,采用面积归一化法测定了各种成分的相对质量分数。研究结果表明,干海带中含有58种挥发性物质,占总质量分数的99.99%,其中醛类17种、醇类14种、酮类7种、烃类13种、酸类3种、其它类化合物4种。醛类化合物占全部挥发性化合物的比例最大,为39.22%,其次为醇类化合物,达到30.73%;烃类占18.51%,酮类6.86%,酸类2.67%。海带的主要挥发性成分是正己醛（20.48%）、1-戊烯-3-醇（10.44%）、丁基甲苯（8.71%）、2-戊酮（3.89%）和(S)-甲基-环氧乙烷（3.85%）等化合物。     

直火和蒸汽加热方式制备豆乳对豆腐风味的影响

通过感官评价和化学分析的方法研究了直火与蒸汽2种加热方式制备豆乳对内酯豆腐风味的影响。感官评价结果表明:直火法豆腐的豆腥味和青草味与蒸汽法相当,而豆香味、甜香味和酸味高于蒸汽豆腐,说明直火豆腐的风味要浓于蒸汽豆腐。采用固相萃取法提取豆腐中风味化合物,通过气相色谱-质谱联用法对风味成分进行了检测,结果表明:乙酸乙酯、甲基环戊烷、苯、正戊醛、1-戊醇、已醛、乙苯、邻二甲苯、间二甲苯、N,N-二甲基乙酰胺、1-辛烯-3-醇、戊酸、丁酸丁酯是直火、蒸汽加热制备的豆腐均存在的风味化合物,此外,甲苯、3-羟基丁醛、已酸、苯甲酸甲酯和苯并呋喃为直火豆腐特有化合物,而氮杂丁烷、丙二酸二乙酯、二甲胺和芍药醇为蒸汽豆腐特有化合物。     

6种不同柑橘蜡在默科特(Murcott)橘上应用的性能评价

经“Decco Fruitshine 402F”、“Water Wax”、“Zivdar Wax”、“FMC 890”、“FMC8201”、“FMC810”、塑料袋单果包装及清洗为对照处理的默科特果实,于常温贮藏35 d.研究结果表明,采后打蜡可以明显减少果实失重,改善果实外观,但影响果实风味.果实的异味与果实内部成分变化特别是乙醇含量的增加密切相关.     

云南省新烟区烟叶与津巴布韦烟叶致香成分比较分析

对云南省新烟区(文山、保山、临沧、普洱)与津巴布韦(马龙德拉、宾杜拉、奇诺伊)烟区生产的KRK26烟叶的致香成分进行了比较分析.结果表明,新烟区上部烟叶新植二烯含量高于津巴布韦烟叶,津巴布韦烟叶挥发性酮类、挥发性醛类、杂环类含量高于新烟区烟叶.新烟区中部烟叶新植二烯含量高于津巴布韦烟叶,津巴布韦烟叶挥发性酮类、挥发性醛类、挥发性醇类、杂环类含量明显高于新烟区烟叶.新烟区下部烟叶多元酸及高级脂肪酸、新植二烯含量高于津巴布韦烟叶,津巴布韦烟叶挥发性酮类、挥发性醇类含量高于新烟区烟叶.主成分分析结果表明,上部烟叶普洱烟叶与马龙德拉、奇诺伊烟叶更加相似,中部烟叶临沧烟叶与马龙德拉烟叶更加相似,下部烟叶新烟区烟叶与马龙德拉烟叶更加相似.     

Ripening and sensory analysis of Guatemalan-West Indian hybrid avocado following ethylene pretreatment and/or exposure to gaseous or aqueous 1-methylcyclopropene

Previous reports showed that both gaseous and aqueous 1-methylcyclopropene (1-MCP) delay ripening of avocado (Persea americana Mill.), but there are no reports of the influence of 1-MCP on its sensory attributes. The objective of this study was to evaluate the effects of ethylene pretreatment and/or exposure to gaseous or aqueous 1-MCP on fruit ripening and sensory attributes of ‘Booth 7’ avocado, a Guatemalan-West Indian hybrid. Separate experiments were conducted during two seasons (2008 and 2009) with fruit harvested at preclimacteric stage in October (early season) and in November (late season). Fruit from Season 1 were exposed to ethylene (4.07 μmol L⁻¹) for 12 h at 20 °C, and stored for more 12 h at 20 °C in an ethylene-free (ethylene, <0.1 μL L⁻¹) room prior to treatment with either aqueous (1.39 or 2.77 μmol L⁻¹ a.i.) or gaseous (3.15 or 6.31 nmol L⁻¹ a.i.) 1-MCP. Ripening was monitored and firmness, respiration, ethylene production and weight loss were measured. Texture profile analysis and sensory analysis were performed on ripe fruit only (firmness, 10–15 N). Fruit from Season 2 were not exposed to ethylene pretreatment but treated only with aqueous 1-MCP 24 h after harvest. Fruit were assessed exclusively for sensory analysis when ripe (firmness, 10–15 N). Treatment with either 1-MCP formulation effectively delayed ripening from 4 to 10 d for early-season fruit, and from 4 to 6 d for late-season fruit. Higher concentrations of 1-MCP of either formulation had the greatest effect on selected pulp textural parameters of early-season fruit; the gaseous formulation had greater effect on late-season fruit quality than the aqueous formulation. In general, sensory panelists ratings of overall liking were not affected by 1-MCP treatment. Both aqueous and gaseous 1-MCP formulations delayed ripening of the Guatemalan-West Indian ‘Booth 7’ avocado without significant loss in appearance or in sensory attributes and, therefore, could be considered for use as a postharvest treatment for this hybrid.     

弱碱与酶联用对烟梗品质的影响

[目的]改善烟梗的质量,提高其可用性,为大规模处理烟梗探讨新方法。[方法]通过利用稀NaOH溶液与酶处理烟梗的方式,先利用稀碱微沸处理30 min,然后55℃浸泡24 h,然后再通过复合酶的作用后,对比研究烟梗的理化性质、香气成分和评吸效果。[结果]通过碱酶处理,使烟梗糖氮比提高了34.4%,糖碱比提高了51.8%,木质素降低了30%,焦油量也降低了23.5%,香气物质含量整体提高了31.2%。[结论]感官评吸结果表明,弱碱与酶的联用可以降低烟梗的木质素含量,提高香味物质含量和梗丝的内在质量。     

复合食用菌风味面条的研究

为了丰富面条口味,研究了复合食用菌风味面条的工艺和配方。对香菇、姬松茸风味物质的提取工艺进行研究,并将2种提取滤液复配后制作面条。结果表明,香菇最适宜提取工艺为超声波处理时间35 min,浸提温度40℃,浸提时间为6 h;姬松茸最适宜提取工艺为超声波处理时间35 min,浸提温度60℃,浸提时间为4 h;当香菇提取液∶姬松茸提取液=1∶3(w.w-)1时制作的面条感官评价最好。