Preparation,characterisation and structure of rabbit (Hyla rabbit) skin gelatine

Rabbit skin was used as a raw material to prepare gelatine. The yield of extracted rabbit skin gelatine was 8.49 ± 0.91% based on a wet weight basis. The bloom strength of 6.67% rabbit gelatine was 457.57 ± 3.302 g, and its gelling and melting temperatures were 27.8 and 34.4 °C, respectively. Sodium dodecyl sulphate‐polyacrylamide gel electrophoresis analysis demonstrated that the content of the subunit components (α chain, β and γ components) of the rabbit skin gelatine achieved 97.915%. Amino acid composition analysis indicated that the total amino acid contents (proline plus hydroxyproline) in the rabbit gelatine were 222 residues per 1000 residues. The high content of the subunit components and amino acids could contribute to the gelatine's suitable gel properties. Rabbit gelatine had nearly all of the characteristic absorption peaks of collagen from rabbit skin, and the loss of the triple helical structure and damage to part of the hydrogen bonds occurred during the conversion of collagen to gelatine.     

A sensitive solid-phase microextraction/gas chromatography-based procedure for determining pentachlorophenol in food

A new method for the determination of pentachlorophenol (PCP) in different foods was developed using capillary gas chromatography (GC) and microwave induced-plasma atomic emission spectrometry (MIP-AED). The analyte is first derivatized and then extracted and pre-concentrated by solid-phase microextraction (SPME) in headspace (HS) mode. A clear matrix effect was found for the different samples investigated, so that standard addition was required for quantification. Detection limits of 0.03-6.0 ng g^-1 were obtained, depending on the sample analysed. The method gave recoveries of 81-109% from spiked samples. Concentration levels of PCP ranged from 0.3 to 1.5 ng g^-1 were found in honey, but no PCP was detected in other samples.     

裂缝压力灌胶法在玉峰塔修缮工程中的应用

本文介绍了电动注胶机串联自动注胶器对玉峰塔石材裂缝压力灌胶施工工法.实践证明,该法施工速度快、裂缝修补效果良好.     

Effects of gelatine type and concentration on the shelf-life stability and quality of marshmallows

The effects of gelatine concentration, bloom strength, and origin on the quality and shelf-life stability of marshmallows were studied. All six sample treatments were carried out under accelerated storage conditions of 25 °C and 75% relative humidity (RH) for 25 weeks. Gelatine A 150 bloom had the highest viscosity because of its highest concentration (2.54%), lowest density and greatest amount of moisture loss producing the hardest marshmallows. Hardness and water activity measurements correlate for all sample treatments indicating that moisture loss is the main mechanism for hardening. With the exception of Gelatine B 2.2%, sugar crystallisation may have occurred in all sample treatments at week 20 which would have an impact on hardness as well. Gel network formation may be contributing towards hardness in Gelatine B 2.2% as there was an increase in hardness but no changes were perceived in water activity.     

Gelcasting of dense and porous ceramics by using a natural gelatine

An improved gel-casting procedure was successfully exploited to produce porous ceramic bodies having controlled porosity features in terms of mean pore size, total pore volume as well as pore geometry. The gel-casting process in which a natural gelatine for food industry is used as gelling agent was firstly set-up to prepare dense alumina and zirconia components. Then, commercial PE spheres, sieved to select proper dimensional ranges, were added to the starting slurries as pore-forming agent. Both alumina and zirconia porous bodies were then produced, having a porosity ranging between 40 and 50 vol%. The fired components were characterised by spherical pores surrounded by highly dense ceramic walls and struts, having a homogeneous and fine microstructure. Their mean pore size was directly dependent on the sieved fraction of the starting PE spheres selected as pore-forming phase.     

Recent trends for the employment of jumbo squid (Dosidicus gigas) by-products as a source of bioactive compounds with nutritional,functional and preservative applications: a review

Only 50%–60% of total seafood catch is used for human consumption, seafood processing being considered as one of the main sources of by-products. Among marine species, jumbo squid (JS; Dosidicus gigas) represents the most important squid fishery, showing an increasing economic interest in many countries. As for any other marine species, the regular cleaning, dressing and processing produce high quantities of by-products (skin, head, fins, viscera, tentacles, unclaimed mantle, etc.) that are rich in many nutrients (proteins, lipids, minerals, vitamins, enzymes, biopolymers, etc.). This review compiles information about extraction and employment of JS by-products with the aim of enhancing their economic value and reduce environmental drawbacks. A special emphasis is given to the relevance in developing methods susceptible to transform by-products into useful and profitable products susceptible to be applied in several industries such as food, medicine, agrochemical or pharmaceutical. Future possible trends for widening this profitable use are mentioned.     

三种常用澄清剂对樱桃酒澄清效果的影响

利用明胶、皂土、壳聚糖对樱桃原酒分别进行了单一澄清剂和复合澄清剂的试验,测定加入澄清剂处理之后的樱桃酒的透光率、吸光度、总酚、单宁和蛋白质含量并进行比较。结果表明:单一使用壳聚糖0.6 g/L处理樱桃酒可起到最好的澄清效果,透光率达94.7%;复合澄清剂确定其在樱桃酒澄清中的最佳组合,即:明胶0.096 g/L、皂土0.8 g/L、壳聚糖0.4 g/L,但对樱桃酒澄清效果较单一澄清剂并无显著优势。     

复合澄清剂对李子酒澄清效果的研究

为提高发酵李子酒的澄清效果,以新鲜李子为原料酿制成李子酒,以明胶、皂土为澄清剂,分别进行单一澄清处理和复合澄清处理,对原酒及处理后酒样的透光率、可溶性固形物、总糖、总酸、总酚、蛋白质及稳定性进行检测。结果表明,18 ℃避光密封静置4 d条件下,当明胶0.4 g/L和皂土0.02 g/L复合澄清处理时,李子酒的澄清效果最好,测得透光率为90.7%;可溶性固形物、总糖、总酸、总酚、蛋白质含量分别为4.8%、24.3 g/L、9.38 g/L、492.9 mg/L、411.4 μg/mL,营养成分损失较少,而且其酒体稳定清亮,无沉淀产生。     

Enzyme immunoassay for the detection of porcine gelatine in edible bird’s nests

Porcine gelatine is a common adulterant found in edible bird’s nests (EBNs) used to increase the net weight prior to sale. This study aimed to develop indirect enzyme-linked immunosorbent assays (ELISAs) for porcine gelatine adulteration using anti-peptide polyclonal antibodies. Three indirect ELISAs were developed (PAB1, 2 and 3), which had limits of detection (LODs) of 0.12, 0.10 and 0.11 µg g^–1, respectively. When applied to standard solutions of porcine gelatine, the inter- and intra-assays showed coefficients of variation (CVs) less than 20% and were able to detect at least 0.5 ng µg^–1 (0.05%) porcine gelatine in spiked samples. The proposed ELISA offers attractions for quality control in the EBN industry.