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31.
Jozef P H Linssen Anneloes L G M Janssens Hanneke C E Reitsma Wender L P Bredie Jacques P Roozen 《Journal of the science of food and agriculture》1993,61(4):457-462
Taste recognition threshold concentrations (TRTC) of styrene were determined in samples of oil-in-water emulsions (30–300 g kg?1 oil) and yoghurts (1–30 g kg?1 fat), spiked with styrene. The observed TRTC increased linearly with increasing fat content and ranged from 0–3 to 2–1 mg kg?1 for the emulsions and from 36 to 171 g kg?1 for the yoghurts. Styrene equilibrium partition coefficients between emulsions and their respective vapour phases were determined. The concentrations of styrene in the continuous aqueous phase of the emulsions and yoghurts were calculated at the TRTC. The styrene concentrations in the continuous phase had constant values of about 15 g kg?1 indicating that perception of styrene for oil-in–water emulsions is determined by the aqueous phase of the emulsion. The concentrations of styrene in the vapor phases above the emulsions and yoghurts were also calculated and were found to be constant at the TRTC. This relationship probably resulted from the equilibrium of distribution of styrene between the respective phases. Commercial yoghurt packed in polystyrene beakers contained styrene levels in the range 2–11 g kg?1, much lower then the TRTC reported. 相似文献
32.
《Landscape Research》2007,32(5):533-557
Within the lifetime of a generation of people now involved in work in the cattle and beef industry in South Dakota, the landscapes of social reproduction that support and give shape to life for people there have been rearranged. Many of the social and physical relationships that developed to support smaller-scale, diverse farms and their surrounding communities are being made redundant by a new system of beef production and retailing. The costs of these redundancies are felt in dwindling small towns and an ever sparser rural population. Considering these changes as parts of landscapes of social reproduction is a means to connect the political and corporate logic driving our food systems to the spatial production of difference in the conditions for livelihood, as well as the spatial production of livelihood itself for both producers and consumers. Such an analysis is necessary in order to address the injustices inherent within our current food system. 相似文献
33.
34.
Dorota Johansson Björn Bergenståhl 《Journal of the American Oil Chemists' Society》1992,69(8):728-733
The influence of water on the interactions between fat and sugar crystals dispersed in triglyceride (vegetable) oils was qualitatively
estimated from sedimentation and rheological experiments. The experiments were performed both with and without food emulsifiers
(monoglycerides and lecithins) present in the oil. The effects of minor natural oil components (nontriglycerides) on the interactions
and on emulsifier adsorption to the crystals were examined by comparing a commercial refined oil and a chromatographically
purified oil. The results show that water generally increases the adhesion between fat and sugar crystals in oils and also
increases the surface activity of the oil-soluble food emulsifiers. Minor oil components give a small increase in the adhesion
between fat and sugar crystals in oils, but do not influence the adsorption of food emulsifiers in any systematic way. 相似文献
35.
D. Wiesenborn Z. Zbikowski H. Nguyen 《Journal of the American Oil Chemists' Society》1995,72(2):183-188
Extract of purple sunflower hulls is a potential red food colorant; however, suitable process conditions must still be identified.
Selected process variables were studied using bench-scale units to prepare, clarify, concentrate and spray dry extracts. Concentration
by evaporation at 32°C and addition of maltodextrin to 15% (wt/dry wt) prior to drying largely eliminated pigment degradation
during those steps. Relative to water extracts, extracts prepared with 5 to 15% ethanol in water generally yielded more pigment
with similar levels of degradation and loss during subsequent processing. Use of 5% ethanol/2% citric acid reduced yield by
about half relative to water, but gave a powder with a lower degradation index and wetting time. Percentage recovery of pigment
during concentration and drying was not greatly affected by solvent type or extraction temperature. 相似文献
36.
FAO/WHO食品添加剂和污染物联合专家委员会(简称JECFA)是国际食品添加剂与污染物安全评价的权威机构,对世界各国所用食品添加剂的安全性进行评价。食品乳化剂是食品工业中一类重要的使用广泛的添加剂。介绍了JECFA关于食品乳化剂的主要品种及使用情况,总结了JECFA对食品乳化剂的安全性评价意见及规定标准。 相似文献
37.
以3-环己基-L-丙氨酸、Boc-L-天冬氨酸-4-苄酯为原料合成二肽L-天冬氨酰-3-环己基-L-丙氨酸-1-甲酯(Ⅰ),以3-羟基-4-甲氧基苯甲醛为原料经过Witting反应、H2还原和DIBAL-H还原三步反应合成3-羟基-4-甲氧基苯丙醛(Ⅱ),然后Ⅰ与Ⅱ在氢气、Pd/C催化作用下进行还原氨化反应,得到目标产物N-[3-(3-羟基-4-甲氧基苯基)丙基]-α-L-天冬氨酰-3-环己基-L-丙氨酸-1-甲酯(Ⅲ),总产率为47%。产物的结构采用IR、~1HNMR、~(13)CNMR和HRMS进行表征,并验证其甜度约为蔗糖的25000倍。合成终产物的最佳工艺条件为:n(Ⅱ)∶n(Ⅰ)=1∶1,Pd/C催化剂用量为反应物总重的10%,体积分数80%的甲醇水溶液为溶剂,反应温度35℃,反应时间20 h。 相似文献
38.
39.
水解酸化-好氧生物法处理工业废水 总被引:21,自引:0,他引:21
水解酸化—好氧生物处理法是近年提出的一种新型处理工业废水的方法。列举了水解酸化工序在生物处理工业废水中的优点,并就其在啤酒废水、屠宰废水、乳品废水、制浆废水以及制药废水中的应用作了介绍。 相似文献
40.
A new non-heating technique was developed for the sterilization of food stuff. Applying a roller compactor, ultra-high pressure sterilization has experimentally demonstrated its ability to sterilize dry powders, such as corn flour and Chinese herbs, with little quality deterioration. Also, the degree of food sterilization was found correlated well with the linear press forces between the rollers, roller gaps, and number of compaction passes. In comparison to the conventional high pressure sterilization technique, the new dry continuous processing method has the advantage of lower investment cost and is more versatile for sterilizing various food powders. 相似文献