为探究油炸对牦牛肉风味物质及品质的影响,对不同油炸温度和时间下的牦牛肉进行感官评分、水分含量、色差值、质构指标的测定;采用顶空固相微萃取-气相色谱-质谱联用技术(headspace solid phase microextraction combined with gas chro...为探究油炸对牦牛肉风味物质及品质的影响,对不同油炸温度和时间下的牦牛肉进行感官评分、水分含量、色差值、质构指标的测定;采用顶空固相微萃取-气相色谱-质谱联用技术(headspace solid phase microextraction combined with gas chromatography-mass spectrometry,HS-SPME-GC-MS)分析油炸前后牦牛肉风味物质的种类和含量变化。结果表明:E_2组(160℃、80 s)牦牛肉感官评分、色差值、质构品质指标均最优。HS-SPME-GC-MS共鉴定出41种挥发性风味物质,包括醛类20种、醇类5种、酯类2种、酮类1种、呋喃类1种、烃类7种、有机酸类1种、其它类4种化合物;A组(参照组)检测出27种化合物,E_2组检测出38种化合物,两组牦牛肉中挥发性成分种类及相对含量有较大差异。根据香气特征雷达图得出,E_2组的香气种类更丰富。利用相对气味活度值对牦牛肉关键风味成分分析得出,A组关键挥发性风味物质有10种,E_2组关键挥发性风味物质有17种,其中反式-2-癸烯醛、壬醛、1-辛烯-3-醇相对气味活度值最大,分别为47.35、35.14、17.63,赋予油炸牦牛肉烤肉味、果香味、蘑菇香味。通过韦恩图得出,A组特有的挥发性风味物质有3种,E_2组特有的挥发性风味物质有14种,A组特有关键香气成分2种,E_2组特有关键香气成分9种。综合风味指标、质构指标和感官评价指标得出,油炸工艺对牦牛肉的风味及品质有明显提升。展开更多
The study evaluated the role of different substrates on water quality, growth and survival of Labeo victorianus fry. Random sampling was used to select 225 fry, stocked at 100/m<sup>3</sup> and fed on shel...The study evaluated the role of different substrates on water quality, growth and survival of Labeo victorianus fry. Random sampling was used to select 225 fry, stocked at 100/m<sup>3</sup> and fed on shell free artemia<sup>®</sup> (40% - 60% crude protein). Each treatment was carried out in triplicates using gravel and sand as substrates and water media without substrate (control). Growth and survival of the fry was monitored over 4 weeks period at a hatchery set-up. Physicochemical parameters were measured weekly while mortality was documented daily. Substrate type had an effect on water quality, growth and survival of fry. Dissolved Oxygen, growth and survival was higher in tanks under gravel substrate than sand and control while mortality was higher (22%) for sand (p ≤ 0.05) than gravel and sand treatments. Fry in gravel substrate had the best growth response (1.77 ± 0.92 g) while control and sand recorded 1.57 ± 0.90 g and 1.45 ± 0.97 g respectively. In contrast, growth was homogenous during the first 2 weeks of the trial but gravel substrate fry significantly out-grew sand and control in the remaining 3 weeks. However, fry in sand and control experienced compensatory growth towards the end of the study. Therefore, gravel substrate enhances L. victorianus performance and is recommended in the introduction of the species into aquaculture and re-stocking back to the wild.展开更多
文摘为探究油炸对牦牛肉风味物质及品质的影响,对不同油炸温度和时间下的牦牛肉进行感官评分、水分含量、色差值、质构指标的测定;采用顶空固相微萃取-气相色谱-质谱联用技术(headspace solid phase microextraction combined with gas chromatography-mass spectrometry,HS-SPME-GC-MS)分析油炸前后牦牛肉风味物质的种类和含量变化。结果表明:E_2组(160℃、80 s)牦牛肉感官评分、色差值、质构品质指标均最优。HS-SPME-GC-MS共鉴定出41种挥发性风味物质,包括醛类20种、醇类5种、酯类2种、酮类1种、呋喃类1种、烃类7种、有机酸类1种、其它类4种化合物;A组(参照组)检测出27种化合物,E_2组检测出38种化合物,两组牦牛肉中挥发性成分种类及相对含量有较大差异。根据香气特征雷达图得出,E_2组的香气种类更丰富。利用相对气味活度值对牦牛肉关键风味成分分析得出,A组关键挥发性风味物质有10种,E_2组关键挥发性风味物质有17种,其中反式-2-癸烯醛、壬醛、1-辛烯-3-醇相对气味活度值最大,分别为47.35、35.14、17.63,赋予油炸牦牛肉烤肉味、果香味、蘑菇香味。通过韦恩图得出,A组特有的挥发性风味物质有3种,E_2组特有的挥发性风味物质有14种,A组特有关键香气成分2种,E_2组特有关键香气成分9种。综合风味指标、质构指标和感官评价指标得出,油炸工艺对牦牛肉的风味及品质有明显提升。
文摘The study evaluated the role of different substrates on water quality, growth and survival of Labeo victorianus fry. Random sampling was used to select 225 fry, stocked at 100/m<sup>3</sup> and fed on shell free artemia<sup>®</sup> (40% - 60% crude protein). Each treatment was carried out in triplicates using gravel and sand as substrates and water media without substrate (control). Growth and survival of the fry was monitored over 4 weeks period at a hatchery set-up. Physicochemical parameters were measured weekly while mortality was documented daily. Substrate type had an effect on water quality, growth and survival of fry. Dissolved Oxygen, growth and survival was higher in tanks under gravel substrate than sand and control while mortality was higher (22%) for sand (p ≤ 0.05) than gravel and sand treatments. Fry in gravel substrate had the best growth response (1.77 ± 0.92 g) while control and sand recorded 1.57 ± 0.90 g and 1.45 ± 0.97 g respectively. In contrast, growth was homogenous during the first 2 weeks of the trial but gravel substrate fry significantly out-grew sand and control in the remaining 3 weeks. However, fry in sand and control experienced compensatory growth towards the end of the study. Therefore, gravel substrate enhances L. victorianus performance and is recommended in the introduction of the species into aquaculture and re-stocking back to the wild.
