鱿鱼酶解工艺优化及酶解液抗氧化活性的研究

以鱿鱼为原料,探讨了酶法水解鱿鱼的工艺条件,同时研究了最佳工艺条件下酶解液的抗氧化活性.试验结果表明:鱿鱼酶解最佳工艺参数为温度55℃、pH值为8、反应时间为5h,加酶量为40％,通过验证试验,在此条件下,鱿鱼的水解度为56.82％.鱿鱼酶解液具有一定的抗氧化活性,对O2-·和·OH的IC50分别为7.2765mg/mL和0.1121mg/mL.     

Relationship between lysyl oxidase activity,pyridinoline content and muscle texture during ice storage of jumbo squid (Dosidicus gigas)

Collagen fibres, stabilised by lysyl oxidase (LOX), play an important role in jumbo squid because they are responsible for the union between various cells; therefore, a close interdependence between their functions and muscle firmness during ice storage has been suggested. In this study, the relationship between LOX activity, pyridinoline (Pyr) content and muscle texture (SF) during ice storage of jumbo squid mantle was evaluated. LOX activity was confirmed within the range of 4.1–7.1 × 10^?3 U g^?1 of protein, leading to an increase in Pyr content, detected in the range of 0.85–1.32 mmol mol^?1 of collagen after 5–20 days. The SF of the muscle became harder during the ice storage time, increasing from 21.08 to 37.95 N. It was therefore possible to establish the relationship between LOX activity, collagen cross‐links (Pyr content) and texture patterns during ice storage of jumbo squid muscle, which increased after 20 days.     

不同蛋白添加剂对秘鲁鱿鱼鱼糜凝胶特性的影响

为了改善秘鲁鱿鱼鱼糜的凝胶特性,本文研究了添加不同种类的蛋白添加剂（卵清蛋白,猪血浆蛋白,乳清蛋白,大豆蛋白）对秘鲁鱿鱼鱼糜凝胶破断力,凹陷距离,凝胶强度,色泽的影响,并通过SDS-PAGE电泳分析其肌原纤维蛋白的降解情况。结果发现:添加卵清蛋白可显著增强鱿鱼鱼糜的破断强度和凝胶强度（p<0.05）,添加乳清蛋白和大豆蛋白对秘鲁鱿鱼鱼糜破断强度和凝胶强度的提高没有明显的促进作用,而添加猪血浆蛋白粉则对秘鲁鱿鱼鱼糜的破断强度和凝胶强度有一定的降低作用。添加各种蛋白粉的鱿鱼鱼糜凝胶凹陷度变化不大。而添加几种蛋白粉均会使鱼糜凝胶的白度降低,其中添加猪血浆蛋白粉对鱼糜白度的影响最大。通过SDS-PAGE分析,秘鲁鱿鱼鱼糜在添加蛋白后肌球蛋白的变化不明显。这表明蛋白添加剂的蛋白酶抑制剂作用效果不大。      

小包装鱿鱼丝精确称量工艺的研究

通过研究发现,在鱿鱼丝称量前,控制其拉丝细度,并对原料预先进行整理、疏散都能有效的提高称量精确率.采用定量初称+二次复秤补偿的方法能更进一步提高称量精度.通过正交实验,结果表明:称量小包装化鱿鱼丝时,堆料密度为0.75 g/cm2,物料均重介于1g与1.5 g之间,补偿量为10%,在此工艺条件下,所获得的称量精确率最高...     

乌贼墨汁多糖的提取及抗氧化作用研究

研究乌贼墨汁多糖的提取工艺和抗氧化能力。采用单因素试验和正交试验对乌贼墨汁多糖提取条件进行优化,同时通过乌贼墨汁多糖对清除DPPH自由基、 ·OH和Fe3＋还原能力的测定考察多糖的抗氧化能力。结果表明,最佳提取条件为加酶量4.5%、料水比1:15(g/mL)、温度50℃、时间4h、pH8,此条件下乌贼墨汁多糖的得率为3.63%。乌贼墨汁多糖具有一定的抗氧化能力,且在一定范围内,墨汁多糖的抗氧化能力与质量浓度呈线性正相关关系,其中对DPPH自由基和 ·OH的半数清除质量浓度分别为3.61mg/mL和8.06mg/mL。     

以鱿鱼内脏酿造鱿酱油的制曲工艺研究

文章以鱿鱼内脏为原料,添加麸皮和面粉,接种米曲霉制曲酿造鱿酱油.以成曲蛋白酶活力为评价指标,研究了蒸料时间、制曲温度、面粉添加量、原料配比、接种量、制曲时间等因素对制曲效果的影响,并在此基础上进行正交试验,结果表明,最佳制曲工艺条件为:鱿鱼内脏与麸皮的质量比为1:2,面粉添加量2％,接种量1.5％,制曲时间120 h.优化后制得的成曲的蛋白酶活力为308.59 U/g.     

酶法水解鱿鱼皮制备多肽工艺的研究

分析了阿根廷鱿鱼皮的一般化学组成,并以其为原料,研究了酶的种类、加酶量、pH、温度及酶解时间对水解度(DH)的影响。采用正交实验对酶解工艺进行了优化,研究结果表明,复合蛋白酶水解鱿鱼皮制备多肽工艺的最适条件为:加酶量14000u/g、pH8.5、酶解温度50℃、酶解时间4h。在此条件下水解度可达20.7%。     

Isolation and properties of 5′-nucleotidase isolated from jumbo squid (Dosidicus gigas) mantle muscle from the Gulf of California,Mexico

The enzyme 5′-nucleotidase of jumbo squid (Dosidicus gigas) mantle was purified and its SDS–PAGE showed a single band of 33 kDa, whereas a protein with a molecular mass of 107 kDa was detected by gel filtration suggesting a homotrimeric nature of this enzyme. Subunits of the named enzyme were not linked by covalent bonds. Isoelectric focusing of this enzyme showed a pI of 3.6–3.8 and presented a hyperbolic kinetics with V_max of 1.16 μM/min/mg of protein, K_m of 1.49 mM, K_cat of 3.48 μM of P_ι s⁻¹ and K_cat/K_m relation of 356.52 ((mol/L)⁻¹ s⁻¹). Purified enzyme preferred AMP as substrate (by 6.7-folds) than IMP, showing a K_m of 6.34 mM, V_max of 0.19 μM/min/mg of protein a K_cat of 0.3388 mol of P_ι s⁻¹ and K_cat/K_m relation of 53.44 ((mol/L)⁻¹ s⁻¹). The low K_m in relation to purified AMP deaminase of the same organism suggested a high contribution of 5′-nucleotidase in AMP degradation in jumbo squid mantle.     

秘鲁鱿鱼肌肉酸性物质去除的初步研究

对秘鲁鱿鱼肌肉的怪异酸味的去除方法进行初步研究,分析秘鲁鱿鱼的主要化学成分和pH值。配制不同种类的10种除酸剂浸泡除酸进行效果对比,检测鱿鱼肌肉的pH值和口感进行酸味评价,测定粗蛋白质和挥发性盐基氮含量作为除酸过程中的质量变化指标,得出用1*和10*除酸剂就能有效去除怪异酸味的目的。     

热处理对鱿鱼上清液中氧化三甲胺降解的影响

氧化三甲胺(Trimethylamine N-oxide,TMAO)是水产品中的一种天然鲜味成分,但在不同条件的影响下也会分解为有害物质,对人体健康造成影响.为研究鱿鱼上清液在热处理过程中TMAO的降解对氨基酸和还原糖的影响,测定了反应前后鱿鱼上清液中甲醛(Formaldehyde,FA)、二甲胺(Dimethylam...