Effect of sodium carbonate on appearance and textural properties of glutinous rice cake

The effect of sodium carbonate (Na₂CO₃) on the appearance and textural properties of glutinous rice cake was investigated. Glutinous rice kernels were soaked in Na₂CO₃ solution (0–1.2 N) at 25 °C for 24 h. Soaked rice was used for glutinous rice cake (GRC) production. The results showed that the rice soaked in Na₂CO₃ had lower protein and fat content, but higher ash content than those of untreated rice, while the amylose content in treated and untreated rice was not significantly different. Moreover, images from scanning electron microscopy showed that the starch granules from rice treated with Na₂CO₃ had smoother surfaces than untreated ones. From the alkali digestion test, the rice kernels treated with Na₂CO₃ suggest a lower gelatinization temperature than untreated rice. The GRC was uniform, and yellow colour was enhanced. Moreover, GRC exhibited an increase in softness and stickiness with increasing Na₂CO₃ concentration.     

硫葡萄糖甙的简便测定法——改进的尿糖试纸法

本文通过实捡,验证简便、快速的尿糖试纸法测定菜籽中硫葡萄糖甙时温度和菜籽酶解液微黄色对测定结果有影响,并提出消涂方法,把此方法延伸应用于测定菜籽粕中硫葡萄糖甙.还利用菜籽粕中的芥子酶,不需外加酶源,由尿糖试纸测定粕中硫葡萄糖甙,且收到较好的效果.     

棉子饼粕在鱼饲料中的应用

介绍了棉子饼及由棉子粕发酵制成的多维菌体蛋白粉在鱼饲料中的添加比例及应用效果。     

湿法炼锌中氯的危害及控制

文章论述了湿法炼锌中氯对系统的影响,提出了利用铜渣净化除氯的方法,分析了铜渣净化除氯中各因素对除氯效果的影响.     

Study of the retrogradation behaviour of rice cake using rapid visco analyser,Fourier transform infrared spectroscopy and X‐ray analysis

Retrogradation of gelatinised starch is the main phenomenon that influences the texture of MiGao (rice cake). The hardness of the MiGao increased during stored at 25 °C for 5 days. Rapid visco analyser (RVA), Fourier transform infrared (FT‐IR) spectroscopy and X‐ray were quantified to analysis the retrogradation behaviour of MiGao. The most significant change in the pasting curve was the increase in peak viscosity over time measured with an RVA. FT‐IR indicated changes in crystallinity of the MiGao crumb. The X‐ray diffraction patterns could be classified as typical of A‐type starch for the fresh MiGao. With aging, the B‐type structure increases, while the A‐type structure remains virtually unchanged. All the results suggested that the main mechanism underlying the changes in properties is suggested to be slow amylopectin crystallisation.     

Labortest zur Minimierung des Versuchsaufwandes bei Pilotfiltrationen

Investigating beer filtration using cellulose fibers requires appropriate methods. One aspect is the preparation of large scale trials. Starting from the filterability test according to Raible and based on the results of diverse pilot scale trials, a laboratory test was created. Apparatus, procedure and methods of assessing the results are described. The new test is qualified for reducing time and effort in upper scale trials, especially in case of varying filter aids compositions.     

Semicontinuous Discharge of Non‐Newtonian Filter Cakes in Electrofiltration

A novel mode of operation for electrofiltration is presented. The newly developed operation procedure allows for cake removal without disassembling the chamber. Highly viscous filter cakes are discharged from the filtration chamber by inserting air which permits a rapid restart of the process. The cleaning time could be reduced from about 10 min to a few seconds. The semicontinuous operation is liable to full automation and allows for cake discharge and filtration in a short period of time. In successive cycles was proved that the process efficiency is maintained using the same membrane. A fully continuous system can be accomplished by assembling several units in parallel in a single filtration press.     

Determination of the overall migration from silicone baking moulds into simulants and food using 1H-NMR techniques

Different silicone baking moulds (37 samples) were characterized with respect to potential migrating substances using ¹H-NMR, RP-HPLC–UV/ELSD and GC techniques. In all cases cyclic organosiloxane oligomers with the formula [Si(CH₃)₂–O] _n were identified (n = 6 … 50). Additionally, linear, partly hydroxyl-terminated organosiloxanes HO–[Si(CH₃)₂–O] _n –H (n = 7 … 20) were found in 13 samples. No substances other than siloxanes could be detected, meaning the migrants mainly consist of organopolysiloxanes. Based on this knowledge, a ¹H-NMR quantification method for siloxanes was established for the analysis of both simulants and foodstuffs. Validation of the ¹H-NMR method gave suitable performance characteristics: limit of detection 8.7 mg kg^–1 oil, coefficient of variation 7.8% (at a level of 1.0 mg kg^–1 food). Migration studies were carried out with simulants (olive oil, isooctane, ethanol (95%), Tenax) as well as preparation of different cakes. From the 1st to 10th experiment, siloxane migration into cakes only slightly decreased, with a significant dependence on fat content. Migration never exceeded a level of 21 mg kg^–1 (3 mg dm^–2) and was, therefore, well below the overall migration limit of 60 mg kg^–1 (10 mg dm^–2). However, migration behaviour into simulants differed completely from these results.     

电子布氏硬度计在电池锌饼检测中的应用

锌饼的硬度与铅、镉、铁等金属杂质含量有关。采用金属布氏硬度法检测锌饼硬度,能快速间接地判定杂质以及添加的金属含量是否异常。介绍了电子布氏硬度计的工作原理和使用条件;对常见的故障及排除方法进行了探讨。