Volatile organo-halogen trace analysis in beverages by thin-layer headspace enrichment and electron-capture gas-chromatography

Applicability of thin-layer headspace (TLHS) procedure giving an aqueous concentrate and also classical purge and trap (PT) in off-line mode to isolate and enrich volatile organohalogen compounds in common beverages was tested. Both enrichment tech-niques were used in combination with gas chromatography – electron capture detection (GC-ECD). TLHS, combined with direct aqueous injection (DAI)-GC-ECD, proved applicable in the determination of volatile organohalogen compounds in all studied beverages, while the PT in a version with no preliminary sample pre-treatment was of limited applicability. Detection limits of the TLHS-based procedure were in the order of 1 ppt. Content of volatile organohalogen compounds in a number of beverages available on the Polish market including mineral waters, beers, juices, carbonated and non-carbonated soft drinks, etc. was determined by means of TLHS-DAI-GC-ECD.     

餐厅网络运营服务系统

本文介绍了××餐饮管理服务有限公司酒店对网络运营管理服务信息系统的开发过程,包括软件工程的需求分析、系统功能结构设计、数据库设计以及调试在内的所有开发过程。本文中所论述的网络运营管理服务信息系统是一个将业务处理从纯人工操作转换成人工与计算机共同处理的一个实例,并对转换过程进行了详细策划,可作为同类计算机网络运营管理服务信息系统的应用参考。     

Response surface modeling for optimization of formulation variables and physical stability assessment of walnut oil-in-water beverage emulsions

The effect of Arabic gum content (5-10% w/w) and walnut-oil concentration (3-6% w/w) on properties of prepared walnut oil/water emulsion, including turbidity loss rate, density, size index, particle size and stability, was investigated using response surface methodology (RSM). For each response, a second-order polynomial model with high coefficient of determination (R²) values ranging from 0.907 to 0.989 was developed using multiple linear regression analysis. The lack of significant difference between the experimental and predicted values proved the adequacy of response surface equations for describing the physical changes of emulsions. An increase of Arabic gum content in range and initial concentration of walnut oil were associated with high emulsion stability and minimum droplet size. It can be concluded that RSM can determine the most suitable formulation (3% w/w walnut oil and 9.62% w/w Arabic gum) to achieve the highest stability in a developed beverage emulsion based on walnut oil.     

我国市售饮料中游离糖含量研究

目的 了解我国市售饮料中游离糖及其单体的含量,为游离糖摄入及其风险评估提供基础数据,为制定完善相关政策提供科学依据.方法 根据我国饮料行业产销量并结合地理分布,2015年采集9类饮料样品共计708份;根据美国分析化学家协会(AOAC)2000.17方法,以高效离子色谱-脉冲安培检测法测定其中的单糖和二糖(葡萄糖、果糖、...     

Hybrid of multi-signal processing methods for detection of small objects in containers filled with beverages using ultrasound

Ultrasound backscattered signals for object detection could be too weak to be perceived when superposed to strong reflection signals, and could also be complicated either in time or frequency domain. These peculiarities raise a challenge for signal processing methods. In this paper four signal processing methods were studied to detect objects in containers. Root mean squares (RMS) method was better in object detection but needed to combine other methods to increase detection success rate. Variance, center frequency pressure ratio (CFPR) and backscattered amplitude integral (BAI) methods have similar overall detection ratings. The optimal signal size, to increase the detection ability, corresponded approximately to the length of reverberation signals before it was dissipated.     

无糖黑木耳薏米保健饮料的工艺研究

对无糖黑木耳薏米保健饮料的加工工艺进行了初步探讨研究。结果表明：以干品黑木耳为原料，采用由0．1％琼脂、0．1％黄原胶和0．1％CMC—Na构成的复合稳定剂的稳定效果较好；采用黑木耳：水=1：15，薏苡曲的添加量为2％，复合稳定剂的用量为0．45％，阿斯巴甜0．05％和均质压力为30MPa的条件生产时，可得到风味优良和稳定性较好的无糖型黑木耳薏米保健饮料。     

壳聚糖在甘薯饮料澄清中的应用

将经过一定预处理的甘薯汁用壳聚糖进行澄清处理,通过正交试验研究确定最佳澄清条件.结果表明采用壳聚糖用量0.6g/L、pH值3.0、时间2.5h、温度60℃的澄清条件效果最佳,透光率可达99%;澄清甘薯汁经调配制得风味佳且澄清透亮稳定性好的甘薯饮料.     

花生蛋白饮料的研制

本文简述了用水溶法提取花生蛋白制备蛋白饮料的工艺流程。并对花生蛋白的溶解性、蛋白饮料的稳定性、风味和色泽与pH关系等关键问题的研究作了重点报道。花生蛋白饮料的营养成分分析表明该饮料是营养价值很高的全价饮料,具有很大的开发价值。     

Quick and reliable estimation of BOD load of beverage industrial wastewater by developing BOD biosensor

An amperometric biosensor for determination of biochemical oxygen demand in wastewater has been developed to overcome the time consuming monitoring procedures. The performance and stability of the immobilized membrane have been investigated at 37 °C and pH 6.8. Immobilized microbial membranes maintain their stability and activity after intermittent use for 400 cycles when stored at 4 °C in sodium phosphate buffer pH 6.8. The response time of the BOD sensor was only 90 min, being independent of the concentration, and the lower detection limit was 1 mg/l. The obtained BOD values showed correlation with that of the conventional method for BOD determination (BOD5) with a deviation of ±10%. Moreover, the sensor exhibits good repeatability (3.39–4.45%) and reproducibility (1.85–2.25%). Software was added to upgrade this sensor and to make it a promising candidate for online monitoring.     

利用芦笋皮加工饮料的工艺研究

以新鲜芦笋皮为主要原料，对芦笋饮料的加工工艺进行了初步探讨，并确定了饮料的合理配方及工艺条件。