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1.
建立了用微波消解技术进行样品前处理,硝酸银标准溶液滴定法测定高温肉制品中氯化钠含量的方法。方法:在样品中加入过量的硝酸银固定住样品中的氯离子,加入硝酸用微波消解仪消解。消解液在转移至容量瓶中后加入与硝酸银等物质的量的氯化钠溶液,混匀后定容。然后以铬酸钾为指示液,用硝酸银标准滴定溶液滴定,根据硝酸银消耗量计算食盐含量。结果:微波消解技术可将样品快速消解完全,该法与国家标准湿化学方法相比无显著性差异。结论:该法操作简单,试剂用量少、重现性好,用微波消解技术大大缩短了样品前处理时间,适于肉制品中食盐含量的测定。  相似文献   

2.
食盐在酱油中的含量,是评价酱油质量的一个重要指标。用酱油做为标准液,电极法直接测定酱油中食盐百分含量,尚未见报导。虽可用纯氯化钠为标准液,但不能解决标准与样品之间的“成份”误差。此外,用莫尔法测定,硝酸银标准液需经常标定。本方法解决了以上问题,取得满意效果。  相似文献   

3.
根据GB/T 5009.54-2003《酱腌菜卫生标准的分析方法》,采用摩尔法,用硝酸银标准溶液测定酱腌菜中的食盐含量。通过对酱腌菜中食盐含量测量不确定度的评估实验,建立了一种简单、适用的测量不确定度评估方法。  相似文献   

4.
目的优化硫酸钡比浊法测定食盐中钡含量的分析方法。方法采用紫外分光光度计对样品悬浊液进行光度测试,分别探讨了测定波长、稳定剂加入量、静置时间对硫酸钡悬浊液体系的影响。结果优化后的方法为:待测溶液加入5 mL甘油-乙醇稳定剂静置10 min后,在波长420 nm处进行测定,标准曲线在钡含量0~3mg范围,相关系数r~2达到0.99915,线性良好,实际检测样品的相对标准偏差在0.71%~4.3%之间,回收率大于90%。结论用分光光度法测定食盐中的钡含量解决了GB5009.42-2016比浊法无法定量测定的缺陷,对进一步监测食盐中的钡提供了帮助,该检测方法可满足食盐中钡含量的定量测定要求。  相似文献   

5.
肉制品中加入食盐,既能抑制有害微生物的繁殖,起到防腐作用,又可增加肉质风味,提高产品的质量。但食盐含量过高同样会影响肉制品的质量及口味,根据国家标准中的相关规定,肉制品中食盐的含量应小于或等于3%。因而,在日常食品检验中,  相似文献   

6.
《食品与发酵工业》2017,(11):238-243
食盐作为肉制品加工过程中的一种重要辅料,具有提供咸味、抑菌和增强风味等作用。但摄入过多的肉制品特别是传统的腌腊肉制品对人体健康十分不利,因为这些肉制品中钠的含量较高,摄入过多会导致人们得高血压、心脏病等心血管疾病风险增加。文章综述了食盐在肉制品加工中的作用、减少肉制品中钠含量的方法及它们对肉制品品质的影响,以期为降低我国传统肉制品中食盐含量提供一定理论参考,提高肉制品的健康性。  相似文献   

7.
肉制品中淀粉含量测定方法改进   总被引:1,自引:0,他引:1  
本文研究肉制品中淀粉含量测定的快速方法,用做完脂肪后的样品,经弃糖、水解、斐林试剂法测定淀粉含量,回收率在88%~108%,变异系数2.6%~5.8%之间在实际工作的应用中取得满意结果.  相似文献   

8.
采用直接沉淀滴定法测定午餐肉中的食盐含量,结果表明,所测样品中食盐含量为1.36g/100g,该方法简单、快速、准确度高,适用于午餐肉中食盐含量的测定。  相似文献   

9.
降低乳化型肉制品中食盐含量研究进展   总被引:1,自引:1,他引:0  
高钠盐摄入已被证明是引起高血压和心血管疾病的一个重要诱因,本文介绍了降低乳化型肉制品中食盐含量的必要性。从食盐的钠替代、风味提升物质降低食盐含量、优化配方降低食盐含量和食盐多糖替代降低食盐含量等方面阐述了降低乳化型肉制品中食盐含量研究现状及发展动态,为研究和生产低盐乳化型肉制品提供参考。  相似文献   

10.
为建立用微波消解技术进行样品前处理,磷钼蓝分光光度法测定肉制品中磷酸盐含量的方法;采用微波消解仪,在肉制品中加入硝酸密闭消解,消解液用磷钼蓝分光光度法在660hm波长处测定样品中磷的含量。结果是微波消解技术可将样品消解完全,采用磷钼蓝分光光度法测定体系中磷酸盐(以磷酸根计)的含量在0~150μg(25ml比色管)时,磷酸盐的含量与吸光度呈线性关系,相关系数0.9999;用本法测定了国家标准物质茶叶与小麦粉等,测定值与标准参考值基本一致,对实际样品的加标平均回收率在97.0%~105.5%之间。该法操作简单,试剂用量少、重现性好,用微波消解技术大大缩短了样品前处理时间,适于肉制品中磷酸盐含量的测定。  相似文献   

11.
建立了一种灵敏、快速的同时测定肉制品中亚硝酸盐和硝酸盐的抑制电导-离子色谱分析方法。样品经超声提取后,以DIONEX IonPac AS19(4mm×250mm)色谱柱分离,用DIONEX EG40淋洗液发生器自动淋洗,采用梯度洗脱方式,以抑制电导检测器进行检测。实验表明,硝酸盐和亚硝酸盐的方法检出限(3S/N)为0.6mg/kg和0.8mg/kg,在0.1~50ug/ml范围内呈良好线性关系,回收率为98.4%和96.5%,重复性(RSD)为2.8%和3.2%。本方法灵敏度高,重复性好,可用于肉制品中的亚硝酸盐和硝酸盐的检测。  相似文献   

12.
The suitability of cellulose/silver nanocomposites to decrease the microbial loads in absorbent materials was studied during the shelf-life of minimally processed foods. Cellulose/silver nanocomposites were synthesised by means of reduction by UV/heat of silver nitrate adsorbed on fluff pulp cellulose fibres. Minimally processed fruits and meat products were packaged in trays containing commercial absorbent pads or silver loaded absorbers, and stored during 10 days at 4 °C. The synthesised antimicrobial nanocomposites were useful to control the population of spoilage-related microorganisms in absorbent pads, being particularly effective in contact with low-protein food products. In contact with silver loaded absorbers, counts of total viable microorganisms and yeasts and moulds were reduced up to 99.9% in juices from kiwi fruit and melon; in drip from poultry and beef meat, microbial loads (total viable counts, lactic acid bacteria) were constantly 90% below the controls. Consequently, silver based absorbent materials could be especially designed to improve hygienic conditions during the manipulation and storage of minimally processed fruit cuts and meat products, but matrix effects must be taken into account.  相似文献   

13.
离子色谱法测定肉制品中亚硝酸盐与硝酸盐的改进研究   总被引:1,自引:0,他引:1  
改进中国GB 5009.33—2010标准方法中离子色谱法测定肉制品中亚硝酸盐与硝酸盐的样品前处理条件。GB5009.33—2010标准采用滤纸过滤样品提取液除脂肪,研究发现滤纸的使用会干扰硝酸盐检测导致其结果严重偏高。本研究改用三氯甲烷除去脂肪有效地解决了该标准方法存在的弊端,同时查明了肉制品中硝酸盐普遍超标并非因企业违规使用含有硝酸盐的添加剂,而是因加工过程中使用了富含硝酸盐的香辛料、辣椒等植物性原料本底。试验证明:改进方法简便、快速、灵敏、准确,适用于肉制品中亚硝酸盐与硝酸盐的定量测定。亚硝酸盐和硝酸盐在所测浓度范围内与峰面积呈良好的线性关系,加标回收率为94.5%~100.5%,相对标准偏差(RSD)为0.70%~3.5%。  相似文献   

14.
Natural and organic food regulations preclude the use of sodium nitrite/nitrate and other antimicrobials for processed meat products. Consequently, processors have begun to use natural nitrate/nitrite sources, such as celery juice/powder, sea salt, and turbinado sugar, to manufacture natural and organic products with cured meat characteristics but without sodium nitrite. The objective of this study was to compare physio-chemical characteristics that affect Clostridium perfringens and Listeria monocytogenes growth in naturally cured and traditionally cured commercial frankfurters, hams, and bacon. Correlations of specific product characteristics to pathogen growth varied between products and pathogens, though water activity, salt concentration, and product composition (moisture, protein and fat) were common intrinsic factors correlated to pathogen growth across products. Other frequently correlated traits were related to curing reactions such as % cured pigment. Residual nitrite and nitrate were significantly correlated to C. perfringens growth but only for the ham products.  相似文献   

15.
《Meat science》2013,93(4):808-815
Natural and organic food regulations preclude the use of sodium nitrite/nitrate and other antimicrobials for processed meat products. Consequently, processors have begun to use natural nitrate/nitrite sources, such as celery juice/powder, sea salt, and turbinado sugar, to manufacture natural and organic products with cured meat characteristics but without sodium nitrite. The objective of this study was to compare physio-chemical characteristics that affect Clostridium perfringens and Listeria monocytogenes growth in naturally cured and traditionally cured commercial frankfurters, hams, and bacon. Correlations of specific product characteristics to pathogen growth varied between products and pathogens, though water activity, salt concentration, and product composition (moisture, protein and fat) were common intrinsic factors correlated to pathogen growth across products. Other frequently correlated traits were related to curing reactions such as % cured pigment. Residual nitrite and nitrate were significantly correlated to C. perfringens growth but only for the ham products.  相似文献   

16.
Nitrate and nitrite are used in meat and fish curing, and in the manufacture of certain cheeses. Nitrate itself has little antimicrobial effect and in most applications could be replaced by lower concentrations of nitrite. Further, improved hygiene diminishes the need for nitrite. The antimicrobial activity and technological needs for nitrate and nitrite are reviewed. It is concluded that the technological needs for nitrite in meat products stored at < 10 degrees C could be met by added nitrite concentrations of 50 mg/kg. The overall effect of nitrate in salted fish appears to be marginal. In such products, Vibrio parahaemolyticus does not grow at salt concentrations of 10% and food poisoning by this organism is not related to the absence of nitrate or nitrite; growth of Clostridium botulinum Type E (the predominant cause of botulism from fish products) is arrested by salt concentrations of 3-4%. Listeria monocytogenes in seafood cannot be controlled by nitrite. The use of nitrate in cheese production could be avoided, or at least reduced to a low level by avoiding silage with a high count of gas-producing Clostridia and hygienic milk collection.  相似文献   

17.
为便于工业盐分级工作,参照国家标准GB-5462"工业盐"的规定方法,寻找一种快速、简便的NaCl含量测定方法--以硝酸银为沉淀剂,以阿拉伯胶做保护剂的分光光度法.  相似文献   

18.
目的采用反滴定法、电位滴定法以及离子色谱法分别对皂类产品中的氯含量进行分析和比较。方法反滴定法采用硫氰酸铵和硝酸银标准溶液进行滴定。电位滴定法采用银电极作为指示电极,硝酸银作为标准溶液滴定。离子色谱法采用Ion Pac AS19阴离子交换色谱柱分离,淋洗液为20 mmol/L KOH溶液,以电导检测器检测。通过对市售6个香皂样品的检测结果分析,进行3种方法的比较。结果反滴定法、电位滴定法、离子色谱法的相对误差为1.2%~2.0%、1.5%~2.2%和0.9%~1.7%;相对标准偏差分别为0.009%~0.014%、0.013%~0.016%和0.008%~0.012%;加标回收率分别为101.9%±4.6%、99.8%±8.3%和101.9%±3.0%。结论从精密度、准确度和加标回收率来看,离子色谱法检测效果最好,值得推广应用。  相似文献   

19.
A flow injection method with novel spectrophotometric detection for the determination of nitrite and nitrate in foodstuffs is presented. The method is based on the reduction of nitrite and nitrate to nitric oxide, with subsequent reaction with iron (II) and thiocyanate in an acid medium, forming FeSCNNO+. The absorbance of the complex, with a maximum at 460 nm, is proportional to the nitrite and nitrate concentrations. The NO is generated in two stages: (1) reduction of nitrate to nitrite in a cadmium copper reductor column and (2) reduction of the nitrite to NO in a sulfuric acid medium. The influence of reagent concentrations and manifold parameters were evaluated. Nitrite and nitrate can be determined in the range of 0.30–3.00 and 1.00–10.00 mg l−1, respectively. The sampling rate of analyses was 30–40 h−1 and, considering a sample of 5.0 g, the determination limit of the method was 20 and 13 mg kg−1 of nitrate and nitrite, respectively. Nitrite and nitrate were determined in vegetables and meat products by the proposed method. The precision and accuracy of the proposed method were comparable to those of the reference spectrophotometric method (official AOAC reference method for the determination of nitrate in foodstuffs).  相似文献   

20.
Determination of salt in oysters by direct titration of the chloride ion, using 0.171N silver nitrate and dichlorofluorescein as an indicator, was compared to the AOAC back titration procedure. The direct titration method was easier to perform and far more rapid than the AOAC procedure and could be done in-plant. No significant differences were observed between the methods; however, the direct titration method was more reproducible at salt concentrations of less than 0.5%. The standard deviations were much greater for the AOAC procedure at low salt concentrations but were similar at higher salt concentrations.  相似文献   

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