鱿鱼猪肉松的加工工艺研究

以猪肉和鱿鱼肉为主要原料,研究了鱿鱼猪肉混合肉松的加工工艺与质量控制方法。结果表明,鱿鱼猪肉松加工配料的最优组合为糖添加量9%,盐添加量1.2%,酱油添加量5%。鱿鱼肉添加量在35%左右时,鱿鱼风味突出,外形和口感良好。炒松工艺以中火10m in转小火5m in的变温方式最有利于产品的感官品质。成品鱿鱼猪肉松具有浓郁的鱿鱼和猪肉松风味、咸甜适中,咀嚼感佳,色泽呈淡金黄色,外形良好,品质符合国家标准规定。     

3种鱿鱼鱼糜凝胶品质比较

目的:寻找更优质的鱿鱼鱼糜制品原料。方法:以秘鲁鱿鱼、北太平洋鱿鱼、阿根廷鱿鱼为研究对象,通过比较3种鱿鱼鱼糜的凝胶强度、持水性、蒸煮损失、流变特性、化学作用力等指标,研究其凝胶特性差异。结果:3种鱼糜的凝胶强度、持水性由高到低依次为阿根廷鱿鱼>秘鲁鱿鱼>北太平洋鱿鱼,蒸煮损失则反之。动态流变温度扫描显示,3种鱼糜的储能模量(G′)均随温度先降低至最小值(45℃),然后升高至最大值(75℃)后再次降低,当温度达到90℃时,阿根廷鱿鱼鱼糜的G′较另两种鱿鱼鱼糜更高。阿根廷鱿鱼鱼糜的离子键、氢键、疏水相互作用显著强于其他两种鱿鱼鱼糜。结论:阿根廷鱿鱼鱼糜的凝胶品质最佳,是鱿鱼鱼糜的最佳原料品种;生产中需要根据3种鱿鱼鱼糜的不同特点利用辅助手段来提高其凝胶品质。     

几种物理处理法对鱿鱼墨黑色素理化特性的影响

以鱿鱼墨黑色素为原料,利用紫外可见光谱仪、红外光谱仪和扫描电子显微镜研究超高压、亚临界和超声波处理对黑色素理化特性的影响。结果表明:超高压处理对黑色素理化特征变化影响最小,而亚临界和超声波处理可以引起黑色素发生较大变化,导致黑色素发生脱氨反应并且破坏亚氨基与金属离子螯合作用,但对于黑色素的特征结构,5,6-二羟基吲哚(DHI)并没有造成显著影响;超声波和亚临界处理对黑色素颗粒物理形态均有一定的破坏作用,超声波处理可使黑色素颗粒破碎生成更小的颗粒和碎片,经处理后直径100nm的颗粒数目比例提高至25%,比原料多了24.5%,其破碎效果大于亚临界处理。超声波处理可作为黑色素可溶性活性物质萃取的有效方法。     

顺序流媒体缓存系统的设计与实现

流媒体数据消耗大量的网络带宽,其中很大一部分是因为热门资源的重复传输,鉴于此情况设计一种顺序流媒体缓存系统,减少不必要的传输.该设计基于代理服务器,针对顺序流媒体独特的存储及访问控制机制,结合代理服务器缓存模块的特征,设计并实现了可用于对顺序流媒体进行缓存的系统.测试结果表明,缓存系统很好的解决了顺序流媒体在缓存上存在的难以命中的问题,可准确的对顺序流媒体进行缓存并在后续访问中完全命中,大幅提高了缓存字节命中率.     

Effect of oregano and thyme essential oils on the microbiological and chemical quality of refrigerated (4 °C) ready‐to‐eat squid rings

The efficacy of oregano and thyme essential oils (OEO and TEO, respectively) in the quality retention of a refrigerated (4 °C) squid (Loligo vulgaris) ring ready‐to‐eat (RTE) product was studied. Essential oils were added at different concentrations to the coating medium during processing. An inhibitory (P < 0.05) effect of OEO on the microbial activity (aerobes, anaerobes, Enterobacteriaceae, psychrotrophs) of the squid rings was observed, with a more pronounced effect as OEO concentration increased. The addition of OEO also led to an inhibitory (P < 0.05) effect on lipid oxidation, as determined by peroxide, thiobarbituric acid‐reactive substance and interaction compound formation; however, no effect (P > 0.05) of the OEO concentrations on lipid oxidation development was detected. The addition of TEO did not lead to an inhibitory effect (P > 0.05) on the microbial activity of the refrigerated RTE squid, although a slight inhibitory (P < 0.05) effect on lipid oxidation was observed in the batches including the higher TEO concentrations.     

Physicochemical changes of pepsin-solubilized and insoluble collagen in jumbo squid (Dosidicus gigas) muscle after cooking process

Collagen is the major connective tissue (CT) protein and one of the main constituents of the jumbo squid (Dosidicus gigas). Therefore, physicochemical changes of pepsin-solubilized collagen (PSC) and insoluble collagen (IC) were studied after cooking (100°C/30 min) of muscle (mantle, fins, and arms). Different pyridinoline (Pyr) contents (the major cross-linking molecule in collagen fibers) were found in the fresh muscle of the three anatomical regions. After the cooking process, a decrease from 10 to 30% in the thermal resistance of collagen was observed, depending on the anatomical region and fraction evaluated. Furthermore, the electrophoretic profile, Fourier transform infrared (FTIR) spectroscopy, and the amino-acid profile revealed that structural changes occurred in the two different collagen fractions caused by the thermal process, and the changes were greater in the mantle. Under the conditions applied in this study, collagen fractions from the squid arms showed more stability during the cooking process due to the high cross-linking degree of their fibers.     

An Amphiprotic Novel Chitosanase from Bacillus mycoides and Its Application in the Production of Chitooligomers with Their Antioxidant and Anti-Inflammatory Evaluation

The objectives of this investigation were to produce a novel chitosanase for application in industries and waste treatment. The transformation of chitinous biowaste into valuable bioactive chitooligomers (COS) is one of the most exciting applications of chitosanase. An amphiprotic novel chitosanase from Bacillus mycoides TKU038 using squid pen powder (SPP)-containing medium was retrieved from a Taiwan soil sample, which was purified by column chromatography, and characterized by biochemical protocol. Extracellular chitosanase (CS038) was purified to 130-fold with a 35% yield, and its molecular mass was roughly 48 kDa. CS038 was stable over a wide range of pH values (4–10) at 50 °C and exhibited an optimal temperature of 50 °C. Interestingly, the optimum pH values were estimated as 6 and 10, whereas CS038 exhibited chitosan-degrading activity (100% and 94%, respectively). CS038 had K_m and V_max values of 0.098 mg/mL and 1.336 U/min, separately, using different concentrations of water-soluble chitosan. A combination of the high performance liquid chromatography (HPLC) and matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometer data revealed that the chitosan oligosaccharides obtained from the hydrolysis of chitosan by CS038 comprise oligomers with multiple degrees of polymerization (DP), varying from 3–9, as well as CS038 in an endolytic fashion. The TKU038 culture supernatant and COS mixture exhibited 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activities. The COS activities were dose dependent and correlated to their DP. The COS with high DP exhibited enhanced DPPH radical scavenging capability compared with COS with low DP. Furthermore, the COS exhibited inhibitory behavior on nitric oxide (NO) production in murine RAW 264.7 macrophage cells, which was induced by Escherichia coli O111 lipopolysaccharide (LPS). The COS with low DP possesses a more potent anti-inflammatory capability to decrease NO production (IC₅₀, 76.27 ± 1.49 µg/mL) than that of COS with high DP (IC₅₀, 82.65 ± 1.18 µg/mL). Given its effectiveness in production and purification, acidophilic and alkalophilic properties, stability over ranges of pH values, ability to generate COS, antioxidant activity, and anti-inflammatory, CS038 has potential applications in SPP waste treatment and industries for COS production as a medical prebiotic.