核磁共振技术研究普通玉米淀粉与玉米抗性淀粉对肉糜持水性的影响

将玉米抗性淀粉、普通玉米淀粉按不同比例添加于猪肉肉糜中,利用磁共振技术研究肉糜中水分状态及含量的变化。结果表明:玉米抗性淀粉与普通玉米淀粉均能提高猪肉肉糜的保水性能。当抗性淀粉的添加量为4%时,肉糜保水性最强,而玉米淀粉的最佳添加量为6%,且添加4%玉米抗性淀粉的肉糜其保水性较添加6%普通玉米淀粉的要好。     

五香鸡肉松的研制

对传统的鸡肉松生产工艺及配方进行了改进,通过适量添加调味料和合理控制煮制时间、烘烤时间,可大幅度缩短鸡肉松加工制作过程,生产出香味浓郁、色泽金黄的优质鸡肉松。     

The properties of gelatin film‐neem extract and its effectiveness for preserving minced beef

The properties of gelatin films developed from neem extract (NE; Azadirachta indica) were determined. Moreover, the developed films were applied to minced beef to test its effectiveness for preserving the meat. The quality attributes of the minced beef wrapped with the developed film were monitored over a 7‐day period in refrigerated storage (4 ± 1°C) and were compared to a control commercial wrap film (polyvinyl chloride). The addition of NE improved the elongation at break, solubility, and antioxidant activity of the gelatin films. After 7 days of storage, the minced beef wrapped with the experimental film showed the highest a* and weight loss values. Gradually, changes in TBARS were more pronounced in the experimental sample. It was concluded that gelatin film containing NE is a potentially promising film that could help delay oxidative reactions. However, some characteristics of the film (eg, mechanical properties and water vapor permeability) need to be improved before putting them to commercial use.     

Effect of Film-Forming Gums in the Preservation of Salted and Dried Indian Mackerel (Rastrelliger kanagurta Cuvier)

Curing preservation of fish is the most popular method in the developing countries and India is no exception. Different film-forming gums, namely sodium alginate, tamarind kernel powder, guar gum and agar agar were tried to find their effect in preservation of salted and dried mackerel and in extending the shelf-life of these products. Various biochemical, microbiological and organoleptic parameters were recorded during the storage period. The treatment of salted dried fish with gum solutions and subsequent formation of film upon drying was found to be the best in preserving the quality of salted fish. The effect of film forming gums on the shelf-life of the products was found to be highly significant ( P< 0·05) as compared to the control.     

Purified NADPH-Sulfite Reductase from Saccharomyces cerevisiae Effects on Quality of Ozonated Mackerel Surimi

The NADPH-sulfite reductase from Saccharomyces cerevisiae was purified to electrophoretic homogeneity by ammonium sulfate fractionation, DEAE Sephacel, Sephacryl S-300 and DEAE Sephadex A-50 chromatography. Optimal pH was 7.3 and temperature 25°C. It was inhibited by IAA, PCMPS, PMSF, NEM, PCMB, cyanide and most divalent metal ions. For the ozonated mackerel surimi ground with purified reductase, the reactive SH increased from 2.29∞10⁵ to 4.46∞10⁵mole/g and gel strength from 256.7 to 360.5g·cm. According to SDS-PAGE, the recovery of myosin heavy chain was observed on the ozonated mackerel surimi with addition of NADPH-sulfite reductase.     

Determination of water activity of canned fish using gravimetric, hygrometric and psychrometric methods

The water activity ( a _w) of canned mackerel, tuna and sardine was determined using three methods: a gravimetric and two instrumental methods. The a _w values obtained by the gravimetric method, which only requires simple laboratory apparatus, were not significantly different from the values obtained by the other two methods, and can be used to determine high a _w values.     

基于模糊技术的速冻水饺工艺参数的应用研究

本文以速冻鲅鱼水饺的生产为例来说明模糊技术在食品加工中的应用,主要介绍了模糊技术的基本原理和工艺优化的实现。将模糊技术与正交试验相结合来研究速冻鲅鱼水饺的生产工艺,通过模糊综合评价确定其最优生产工艺参数。     

高压处理对碎牛肉重组特性的影响

为提高低值碎牛肉的利用率,改善其重组特性,将碎牛肉制成牛肉肠经高压处理,对其蒸煮损失率、非压出水分、保水性、黏结性和微观结构进行研究。通过单因素试验得出:碎牛肉的蒸煮损失率随着压力的增大、保压时间的延长和保压温度的增加均呈先降后升趋势,非压出水分、保水性和黏结性呈先升后降趋势,并都在400 MPa,15 min,20℃附近达到最佳值;通过响应面(SEM)法分别得到高压改善碎牛肉蒸煮损失率(500 MPa,25 min,35℃)、非压出水分(431 MPa,15℃,18.6 min)、保水性(500 MPa,25 min,35℃)和黏结性(383 MPa,35℃,25 min)的最适处理条件,并对其四项指标综合考虑进行最优化求解,求得高压提高碎牛肉重组特性的最佳处理条件为469 MPa、35℃、25 min;经研究发现,该条件下处理后的碎牛肉各项指标明显优于对照组,且微观结构也更加规则有序。由此可知:适当的高压处理可以有效改善碎牛肉的重组特性,具有较好的应用前景。     

酶解马鲛鱼下脚料制备海鲜酱工艺优化

对马鲛鱼下脚料水提液进行酶解,通过单因素及正交酶解试验,优化了马鲛鱼下脚料的酶解工艺,再利用酶解液制备海鲜调味酱,并与市售海鲜酱的感官品质进行对比分析。结果表明,马鲛鱼下脚料的最佳酶解工艺条件为：中性蛋白酶用量500 U/g,液料比（V_水∶m_下脚料）3∶1 （mL/g）,酶解温度55 ℃,pH值 7.5,酶解时间5 h,该酶解条件下酶解液中氨基酸态氮的质量浓度高达（0.325±0.004） g/100 mL。制备的海鲜酱与市售海鲜酱的口感相当,产品理化及微生物指标符合相关国家标准要求。     

高压处理对牛肉肌红蛋白及颜色变化的影响

室温下不同压力(200、400、600和800MPa)，20min处理对绞碎牛肉颜色及肌红蛋白的影响进行了研究。结果显示：随压力的上升，L^*值增加、a^*值下降，肌肉逐渐失去红色变为灰棕色。同时，肌红蛋白总量显著降低，高铁肌红蛋白的比例在压力400MPa以上时显著增加。真空包装不能减轻压力导致的变色，而添加亚硝酸钠能对色泽起到稳定作用。压力处理导致色泽变化的原因可能是由于二价铁的肌红蛋白氧化成三价铁的高铁肌红蛋白、球蛋白的变性及结构的变化所致，可通过处理前腌制形成亚硝基肌红蛋白来稳定色泽。