共查询到20条相似文献,搜索用时 140 毫秒
1.
2.
3.
《中国调味品》2021,(9)
通过对豆腐乳理化指标和感官特征进行分析,利用感官评判的方式提取豆腐乳的前4个感官主成分和前4个理化主成分,对豆腐乳感官品质影响较大的前4个主成分贡献率分别为49.66%、16.33%、12.85%、6.49%;对豆腐乳理化特性影响较大的前4个主成分贡献率分别为32.67%、21.33%、17.85%、7.22%。以主成分分析结果为输入参数,利用遗传算法建立神经网络预测模型,对豆腐乳的综合评价进行预测,与感官评分和理化特性的主成分综合评分结果进行对比,数据表明,二者之间的偏差值最大为9.92%,具有较大的预测可信度,表明利用遗传算法能够对豆腐乳的感官综合评价进行有效预测。 相似文献
4.
目的:设计一种较为准确的生菜贮藏时间鉴别模型。方法:以新鲜生菜为试验对象,分别采用主成分分析、鉴别主成分分析、模糊鉴别主成分分析3种特征提取方法对预处理后的生菜近红外光谱数据进行特征提取,选出具有较高准确度的贮藏时间鉴别算法,并建立基于模糊鉴别主成分分析的生菜贮藏时间鉴别模型。结果:利用模糊鉴别主成分分析进行特征提取后的鉴别准确度显著增加。主成分分析、鉴别主成分分析和模糊鉴别主成分分析的最高准确度分别为46.67%,86.67%,93.33%。结论:采用近红外光谱分析和模糊鉴别主成分分析的鉴别模型具有较高的准确性和优越性。 相似文献
5.
6.
7.
8.
利用高效液相色谱检测庐山云雾茶水溶性成分,建立庐山云雾茶水溶性成分指纹图谱,并对共有峰相对峰面积进行主成分分析。其中庐山云雾茶液相指纹图谱有38个共有峰,样品与对照指纹图谱相似度均在0.93以上,经主成分分析得到3个主成分,累计方差贡献率达到81.7%。该方法的庐山云雾茶真伪判别率达100%。利用气相色谱-质谱联用技术检测庐山云雾茶挥发性成分,共鉴定出38种挥发性成分,并对共有峰相对峰面积进行主成分分析。经主成分分析得到3个主成分,累计方差贡献率达到83.8%。该方法庐山云雾茶真伪判别率达100%。本试验为庐山云雾茶真伪识别提供一种新思路。 相似文献
9.
10.
11.
Crithmum maritimum L. is a halophyte and chasmophyte apiaceous plant, which grows on all the world's coastlines but is particularly abundant in France. The essential oil obtained by steam distillation from samples of leaves of Crithmum maritimum L. gathered in two areas of France, Brittany and Provence, was analysed first by ultraviolet spectroscopy and secondly by capillary GC.
In the first analysis, two distinct UV spectra were obtained depending on the two origins. In all, about 27 components were identified in the two sample types by GC, and they were quantified when possible. Dillapiole is the main constituent representing 75% of the oil whatever its origin. 相似文献
In the first analysis, two distinct UV spectra were obtained depending on the two origins. In all, about 27 components were identified in the two sample types by GC, and they were quantified when possible. Dillapiole is the main constituent representing 75% of the oil whatever its origin. 相似文献
12.
13.
14.
15.
16.
J.P. BARTLEY 《Journal of food science》1988,53(1):138-140
The volatile constituents of the “Babaco” (Carica pentagonia) have been isolated by concentration of the headspace vapors on Tenax-GC. Of the 37 compounds identified aliphatic esters account for 84% of the total area, the major components being ethyl butanoate and ethyl hexanoate. These findings conflict with a previous report in which alcohols were claimed to be the main constituent when this fruit is grown in New Zealand. 相似文献
18.
Sachchidananda D Chowdhuryc 《Journal of the science of food and agriculture》1990,52(3):315-329
In two experiments, commercial laying pullets and hens were fed diets containing either low or high concentrations of beta-aminopropionitrile (BAPN), the toxin present in some legume seeds in the genus Lathyrus. BA PN was fed as mono-beta-aminopropionitrile fumarate. The main effects of feeding BAPN to laying birds appear to be on shell formation, egg weight and egg production. Heavier eggs, abnormal in shape and shell texture, were frequently obtained when BAPN was included in the diet. Effects on both egg weight and egg malformation were observed with or without a reduction in egg production. The toxic level of BA PN fumarate in the diet of laying birds appears to lie between 0.1 and 0.2 g kg?1. Considering BAPN content in seeds of different Lathyrus species and the level of active constituent of BAPN fumarate which had adverse effects, it was found that Lathyrus seeds which contain BAPN as a toxic constituent have margins of safety and could be utilised to constitute a proportion of the layer diets without any deleterious effects. 相似文献
19.
20.
d-Carvone or (4S)-(+)-carvone has a caraway/dill odour and is the main constituent of caraway (Carum carvi) and dill (Anethum graveolens) seed oils whilst l-Carvone or (4R)-(−)-carvone has a sweet spearmint odour and is the main constituent of spearmint (Mentha spicata). Carvone is produced by both extraction and purification of essential oils from caraway, dill and spearmint seeds and by chemical and biotechnological synthesis. 相似文献