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排序方式: 共有923条查询结果,搜索用时 245 毫秒
151.
白瓶啤酒生产的问题与解决措施 总被引:1,自引:0,他引:1
白瓶啤酒现在成为啤酒家族的新宠,但随之也出现了一些问题,本文着重解释了解决这些问题的各种工艺措施。 相似文献
153.
Philip O Owuor Herman O Odhiambo Janet M Robinson Sarah J Taylor 《Journal of the science of food and agriculture》1990,52(1):63-69
Green leaf standard, chemical composition and quality of black tea (Camellia sinensis (L) O Kuntze) change with plucking intervals. Long plucking intervals lead to poor leaf standard with a lot of mature leaves and lower theaflavins, the sum of volatile flavour compounds imparting a sweet flowery aroma (group II volatile flavour compounds), caffeine contents and tasters' evaluations of black tea. The sum of volatile flavour compounds imparting inferior, grassy, green flavour (group I volatile flavour compounds) to tea, however, increases with long plucking intervals. 相似文献
154.
瓶装黄酒杀菌条件与风味关系研究 总被引:2,自引:0,他引:2
对瓶装黄酒杀菌温度、时间等对酒质、风味的影响作了系统的研究和分析。实验表明:杀菌温度在60℃-65℃,随杀菌时间延长酒质得到改善;当杀菌温度超过70℃时,杀菌时间应控制在1h以内;当75℃时杀菌超过30min,黄酒风味有下降的趋势;80%以上,黄酒风味随杀菌时间延长而变劣。 相似文献
155.
本文通过对氧气在啤酒生产过程中的作用,影响和危害的分析,对啤酒生产过程的设备工艺进行改造调整,以及对回收的CO2在酿造,过滤和包装等过程的全用,降低成品啤酒中含氨量,减少啤酒的氧化味,提高产品的质量。 相似文献
156.
Dietmar Bartschat Armin Mosandl 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1996,202(4):266-269
The direct enantioseparation of 2-phenylpropanol, 2-phenylpropanal and 2-phenylpropanal dimethyl acetal was achieved, using enantioselective gas chromatography and heptakis-[2,3-di-0-acetyl-6-0-tert.butyldimethylsilyl]--cyclodextrin (DIAC--CD) or octakis-[2,3-di-0-acetyl-6-0-tert.butyldimethylsilyl]--cyclodex-trin (DIAC--CD) as the chiral stationary phase. Their odour characteristics and threshold values were investigated by enantioselective gas chromatography/olfactometry. Starting from commercially available (R)-2-phenylpropionic acid, enantiopure (R)-configured reference compounds were synthesized. 相似文献
157.
Susane Oshiro Marta Ramalho Paloma Cristina Durães Raissa Andrade Karolina Silva Flaviano Silvério 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2020,37(9):1510-1519
ABSTRACT
p-Cresol has been identified as a flavouring compound in cheeses; however, scientific studies have already identified p-cresol as a potential chemical contaminant in environmental matrices. Thus, the objective of this study was to evaluate four traditional methods for extracting p-cresol from cheese samples in order to validate the best method, and finally to apply it to five cheese samples with different origins, processing and ripeness times. The analyses were performed by gas chromatography-mass spectrometry after derivatisation of p-cresol with anhydride acetic and pyridine. Better results were achieved by the QuEChERS method, which showed recovery higher than 80%, relative standard deviation lower than 16%, limit of quantification of 5 μg kg?1 and linearity between 5 and 400 μg kg?1 with R2 0.99. p-Cresol was quantified in almost all of the samples analysed at different concentration levels, which were in an increasing order at μg kg?1: Cheddar (< LOQ), Parmesan (8 ± 0.7), Gorgonzola (103 ± 14), smoked Provolone (365 ± 28) and barbecue cheese (1001 ± 187). Although no maximum residue limit has been established for p-cresol in food, the results suggest that cheeses exposed to charcoal combustion notably increase the p-cresol levels and may represent a hazard to human health, especially in risk groups such as patients with chronic kidney disease who have serious problems with p-cresol. 相似文献
158.
Twenty-four Murrah buffaloes (60 days pre-partum) were divided into four equal groups (T 1 , T 2 , T 3 and T 4 ) and were supplemented with 0, 1000, 1500 and 2000 IU α-tocopheryl acetate per day up to 30 days of lactation, and half of these doses from 30 to 60 days of lactation. Milk samples collected fortnightly were analysed for vitamin E, fat, and development of oxidized flavour, with and without copper addition by a panel of judges, and chemically by the thiobarbituric acid test. Scores for oxidized flavour ranged from 0 to 10 with 0–4 as definite, 5–7 as light and 8–10 having no defect. The α-tocopherol content in milk fat (µg/g) averaged 20.55, 25.56, 29.98 and 31.38 in T 1 , T 2 , T 3 and T 4 groups, respectively. The addition of Cu in the milk significantly increased milk fat oxidation. Better stability of milk in T 3 and T 4 groups was observed, which might be due to a higher level of milk α-tocopherol. Addition of 1500 IU α-tocopheryl acetate in the diet of buffaloes helped in improving the oxidative stability of milk. 相似文献
159.
Yong-Jun Cha Hyung-Hee Baek Thomas C-Y Hsieh 《Journal of the science of food and agriculture》1992,58(2):239-248
Volatile components in flavour concentrates prepared from crayfish (Procambarus clarkii Girard) processing waste at two temperatures (85°C and 100°C) were compared. The presence of 121 compounds was established. Among these, 78 compounds were positively identified of which 50 were detected in crayfish for the first time. These compounds were mainly N- and S-containing compounds, ketones and aldehydes. The amounts of aldehydes and ketones were 1.5 and 1.4 times higher in the 85°C concentrates, respectively; and the amounts of N-containing compounds were 2.3 times higher in the 100°C concentrates. 相似文献
160.