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71.
The effect of fructooligosaccharides on the sensory characteristics of cooked sausages 总被引:1,自引:0,他引:1
The effect of a short chain fructooligosaccharide on the sensory properties of conventional and reduced-fat cooked meat sausages has been studied in products in which a fat reduction of close to 40% was obtained. The fibre assayed was used in sufficient amounts to constitute between 2% and 12% of the final product. The energy value reduction of the final products was close to 35%. Instrumental measurements of colour and texture were performed. Sensory properties were estimated by a hedonic test. A correlation principal component analysis was performed. The results showed that the sensory and textural properties and the overall acceptability were very good, which indicated that this fibre can be considered a good fat replacer in meat products. Thus, with its addition, a reduced calorie product enriched with soluble dietetic fibre is obtained. 相似文献
72.
González-Martín I González-Pérez C Hernández-Méndez J Alvarez-García N 《Meat science》2003,65(2):713-719
A near infrared spectrometer equipped with a standard 1210/210 bundle remote reflectance fibre-optic probe, with a 5×5 cm quartz window, was used for the determination of fatty acids in the subcutaneous fat of Iberian pigs. A comparative study was made of the determination of fatty acids (C14:0, C16:0, C18:0, C18:1, C18:2, C18:3, C20: 1, Σpolyunsaturated, Σmonounsaturated and Σsaturated) in samples of subcutaneous fat from Iberian pigs by direct application of the fibre-optic probe on samples of whole subcutaneous fat and with cam-lock cups, assessing extracts of total lipids with diethyl ether. The regression method employed was modified partial least squares (MPLS). Calibration of 157 samples, using the fibre optic probe, allowed determination of fatty acids in the following ranges: C14:0 (0.78-1.77), C16:0 (15.87-29.74), C18:0 (4.61-15.90), C18:1 (43.50-61.27), C18:2 (2.03-13.94), C18:3 (0.13-1.14), C20:1 (0.45-2.32), Σpolyunsaturated (2.31-14.82), Σmonounsaturated (47.37-65.62), Σsaturated (22.09-47.31), with corrected standard errors of prediction SEP(C) of 0.093, 0.56, 0.67, 0.94, 0.42, 0.10, 0.20, 0.46, 0.94, 0.83, respectively. The robustness of the method using the fibre-optic probe was tested in a slaughterhouse using 23 samples for external validation, giving multiple correlation coefficients (RSQ) for C14:0, C16:0, C18:0, C18:1, C18:2, C18:3 C20:1, Σpolyunsaturated, Σmonounsaturated, Σsaturated acids of 0.72, 0.94, 0.72, 0.79, 0.88, 0.55, 0.17, 0.88, 0.74, and 0.90, respectively, and a corrected standard error of prediction [SEP(C)] for these acids (%) of 0.11, 0.60, 0.84, 1.20, 0.77, 0.11, 0.30, 0.76, 1.21, and 1.18, respectively. 相似文献
73.
Volatile compounds in fresh meats subjected to high pressure processing: Effect of the packaging material 总被引:3,自引:0,他引:3
The effect of high pressure treatment (400MPa, 10min at 12°C) on the volatile profile of minced beef and chicken breast, packaged with or without aluminum foil in a multilayer polymeric bag, was investigated. The analysis of the volatile fraction was carried out by dynamic headspace extraction coupled to gas chromatography-mass spectrometry. Pressurization produced significant changes in the levels of some volatile compounds presumably coming from microbial activity. Some alcohols and aldehydes decreased, while other compounds, such as 2,3-butanedione and 2-butanone, were more abundant in high pressure processed meats. A significant migration of compounds from the plastic material was observed, mainly branched-chain alkanes and benzene compounds. Two functions built by the principal component analysis explained a high percentage of the variance and could be used to separate the samples into four distinct groups, according to high pressure treatment and packaging material. 相似文献
74.
A rapid and highly specific real-time quantitative PCR, based on the amplification of a fragment of the mitochondrial 12S ribosomal RNA gene (rRNA), has been developed for the quantitation of pork (Sus scrofa) in binary pork/beef muscle mixtures. The method combines the use of pork-specific primers, that amplify a 411bp fragment from pork DNA, and mammalian-specific primers amplifying a 425-428bp fragment from mammalian species DNA, which are used as endogenous control. An internal fluorogenic probe (TaqMan), that hybridizes in the "pork-specific" and also in the "mammalian" DNA fragments is used to monitor the amplification of the target gene. A comparison of the cycle number (C(t)) at which mammalian and pork-specific PCR products are first detected, in combination with the use of reference standards of known pork content, allows the determination of the percentage of pork in a mixed sample. Analysis of experimental pork/beef muscle binary mixtures demonstrated the specificity and sensitivity of the assay for detection and quantitation of pork in the range 0.5-5%. 相似文献
75.
Tomato industries yield a high amount of by-products mainly tomato peel and seeds. Since tomato peel is rich in lycopene, the direct addition of peel to food products could be a way to use this by-product to obtain a new products enriched in lycopene. This work describes experiments performed to develop dry fermented sausages (salchichón) containing this carotene. 0%, 0.6%, 0.9% and 1.2% (w/w) of dry tomato peel was added to the meat mixture used in sausage manufacture. A slight losts of lycopene was detected after 21 days ripening, however, levels remained between 0.26 and 0.58 mg of lycopene/100 g of sausage. The sensory and textural properties and overall acceptability of all sausages were good, indicating that tomato peel could be added to dry fermented sausages to produce a meat product enriched in lycopene. 相似文献
76.
Lorenzo JM Purriños L Bermudez R Cobas N Figueiredo M García Fontán MC 《Meat science》2011,89(1):105-109
The polycyclic aromatic hydrocarbon (PAH) content in two traditional smoked sausages from Spain was determined. Results showed, that total average levels of PAHs found were higher in "Chorizo de cebolla" (101.81 vs. 98.48 μgkg(-1)). Most contents of PAHs found in both sausages were phenanthrene, naphthalene and anthracene. The maximum level for benzo[a]pyrene (BaP) of 5 μgkg(-1) in smoked meat products was not exceeded in any samples. BaP represented a 0.73% and 1.15% with respect to the total sum of the 15 PAHs that were investigated in this study for "Chorizo gallego" and "Chorizo de cebolla", respectively. Correlation statistic analysis (P < 0.01) of the contents from samples analysed, showed that BaP was a good marker for Σ15 PAHs in "Chorizo gallego" samples (R(BaP/Σ15PAHs) = 0.77; P < 0.01) and it was a good marker for 7 U.S. EPA probably carcinogenic PAHs in "Chorizo de cebolla" samples (R(BaP/7EPA) = 0.95) and in "Chorizo gallego" samples (R(BaP/7EPA) = 0.81). 相似文献
77.
以非道路高压共轨柴油机干式缸套为研究对象,采用仿真与测试相结合的方法,在热态、热态预紧、热态预紧过盈、热机耦合和热机耦合过盈工况下对比研究了载荷变化对缸套综合变形特征的影响规律,研究了不同缸套变形特征对活塞–缸套摩擦副的机油消耗量、窜气量及摩擦损失的影响规律。研究结果表明,在热态工况下,摩擦损失功最大,为1.09 kW;在热态预紧工况下,机油耗最大,为4.29 g/h;在热态预紧过盈工况下,窜气量最大,为15.71 L/min。在热态工况下施加预紧力,摩擦损失功减小,机油耗和窜气量增大,继续施加缸套过盈载荷,摩擦损失功和窜气量增大,机油耗减小;在热机耦合工况下施加缸套过盈载荷,摩擦损失功、机油耗和窜气量均增大。 相似文献
78.
继年产万t洗衣粉项目建成投产后 纳爱斯年产万t洗涤用品系列技改项目已获浙江省计经委浙江省重点建设领导小组批准 列入省重点建设项目。整个系列项目计划总投资亿元 《日用化学品科学》2000,23(2):33
继年产12万t洗衣粉项目建成投产后 ,纳爱斯年产40万t洗涤用品系列技改项目已获浙江省计经委、浙江省重点建设领导小组批准 ,列入省重点建设项目。整个系列项目计划总投资3 8亿元(其中用外汇970万美元) ,3年时间完成。系列技改项目包括引进中性油脂连续皂化及10万t/a透明皂自动包装机技改项目、30万t/a液洗系列产品配制技术改造项目 ,以及其配套引进30万t/a液洗系列产品自动灌包装线和塑制品成型线技术改造项目等。该系列项目建成投产后 ,可新增销售收入26 5亿元 ,利税2 66亿元。纳爱斯年产40万t洗涤用品… 相似文献
79.
1999年12月16日,卡塔尔乙烯公司(QVC)就二氯乙烷综合生产厂建设项目(4.75亿美元贷款)正式签订协议。在BanqueParibas、阿拉伯石油投资公司(Apicorp)和CreditSuisseFirstBoston的安排下,这一项为期12年货款将部分支持QVC计划在Mesaieed的6.5亿美元二氯乙烷综合厂的建设。这一贷款协议的签订为项目的工程建设、完成及建设合同的执行铺平了道路。该项目已于6月被乌德(Kruppuehde)与技术石油(Technipetrol)的德/意集团公司以4… 相似文献
80.
China National Petroleum Corporation 《中国油气》2007,14(1):58-61
China National Petroleum Corporation (CNPC) is taking on the world with great success. The nation's top oil producer began energy-exploration projects for the first time in a number of countries last year, such as Equatorial Guinea, Uzbekistan and Argentina. This brings the total number of overseas countries where CNPC has a total of 66 projects in operation to 26, forming five major operational regions including Africa, Central Asia, South America, the Middle East and Asia Pacific. With the overseas oil and gas business brought under rapid development, the newly additional recoverable reserves of the company worldwide reached 65.40 million tons. 相似文献