宣威火腿加工过程游离氨基酸变化规律研究

以宣威火腿为研究对象,利用氨基酸自动分析仪检测宣威火腿不同加工阶段(鲜肉、腌制后90d、210d、270d与360d)的股二头肌肌肉中游离氨基酸含量的变化。结果显示：在腌制过程中,肌肉中游离氨基酸的含量呈现持续上升趋势。其中,腌制360d的肌肉中游离氨基酸的含量最高,此阶段含量较高的游离氨基酸分别为谷氨酸、赖氨酸、丙氨酸和亮氨酸,较低的分别为组氨酸、蛋氨酸、苏氨酸和酪氨酸。     

Biochemical changes during processing of traditional Jinhua ham

Jinhua ham is the most famous traditional meat product of China and one of the most famed dry-cured hams in the world. Its processing consists of six stages: green ham preparation, salting, washing and sun-drying and shaping, ripening, and post-ripening. Intense proteolysis and lipolysis occur during processing period. As a result, the content of free amino acids in final ham products is 14-16 times that of green ham, and 191 volatile compounds have been identified during processing, which make a major contribution to the flavor of Jinhua ham.     

Lipolysis in dry-cured ham: Influence of salt content and processing conditions

Fatty acid composition of neutral lipids (NLs), polar lipids (PLs) and free fatty acids (FFA) from the intramuscular fat of Semimembranosus and Biceps femoris muscles was analysed in 46 Iberian dry-cured hams processed with different amounts of salt (6% high salt batch – HS vs. 3% low salt batch – LS w/w) and different processing systems (traditional – T vs. modified – M).

Total amounts of saturated (SFA), monounsaturated (MUFA) and polyunsaturated (PUFA) fatty acids in NLs decreased in similar proportions during processing of the hams as well as SFA, MUFA and PUFA in the PL fraction, whereas the amounts of SFA, MUFA and PUFA of FFAs significantly increased in Semimembranosus and Biceps femoris muscles. The amount of total fatty acids (TFA), from NLs and PLs, decreased in both muscles throughout the processing. Such a decline was more intense in HS hams than in LS ones, which could be a sign of a promoting effect of sodium chloride on lipolysis. However, the increase in FFA content throughout processing was not more intense in HS hams. Processing conditions studied in this work did not affect the changes in the fatty acid content of each fraction.     

宣威火腿的传统工艺特色

详细介绍了我国三大“著名火腿”之一的宣威火腿传统加工工艺、规格等级划分标准和质量控制指标。     

肌内脂肪及其在加工过程中的水解变化

人们对肌内脂肪一直了解得很少,肌内脂肪的组成及水解程度会影响到产品的最终风味特性.本文首先阐述了肌内脂肪的组成及其主要影响因素,随后讨论了肌肉中脂肪的水解及其与氧化的关系,在结论中还指出了目前仍需要进一步研究的内容.     

Proteolysis,protein oxidation and protease activity in dry‐cured Xuanwei ham during the salting stages

Twenty‐four experimental dry‐cured Xuanwei hams were salted using a standard method for 90 days. The proteolysis, protein oxidation and protease activities in biceps femoris (BF) and semimembranoesus (SM) muscles of dry‐cured Xuanwei ham were investigated during the salting phase. At the end of salting, the salt content increased to 35.2 g kg^?1 muscle in BF and 54.2 g kg^?1 muscle in SM. During the salting stage, salt soluble proteins were degraded mainly into water soluble proteins that were further broken down to peptides with molecular weights mostly greater than 1 kDa. Although large amounts of smaller peptides and free amino acids were generated, especially when the hams were aged. The carbonyl contents were increased but lower than 1.57 nmol mg^?1 proteins in muscles during the salting stage. The cathepsin B, dipeptidyl peptidase I (DPP I), alanyl (AAP), arginyl (RAP) and leucyl (LAP) aminopeptidase all remained active while salt content strongly inhibited cathepsin L and DPP IV in the first 90 days. The results suggested that the salting process promoted the hydrolysis of proteins, and increased the muscle protein oxidation at a slower rate.     

金华火腿生产过程中脂质水解特性研究

60只重量为6.2～6.9 kg的原料腿按传统工艺加工金华火腿.分别于原料腿、盐后、晒后、成熟中期、成熟结束、后熟1和后熟2七个工艺点随机取5只腿的股二头肌为样品,分析总脂肪、甘油酯、磷酯、游离脂肪酸和相关指标的变化.结果显示：生产过程中磷脂的变化较大,约有66.67%的磷酯发生了水解.相关性分析发现：磷酯和甘油酯含量与游离脂肪酸含量之间的R2分别为0.91和0.67,磷酯是脂类物质中最主要的风味前体物质.生产过程中总游离脂肪酸含量呈上升趋势,饱和脂肪酸和单不饱和脂肪酸的相对含量提高,多不饱和脂肪酸的相对含量下降,其中亚油酸的含量下降最明显,为4.48%.亚油酸可能是氧化形成风味成分的主要脂肪酸.     

固相微萃取法分析宣威火腿挥发性风味成分条件的优化

目的研究优化萃取宣威火腿风味物质的固相微萃取操作条件。方法采用固相微萃取法(solid phase microextraction,SPME)和气相色谱-质谱联用法(gas chromatography-mass spectrometry,GC-MS)来萃取及分析宣威火腿中的风味成分,选取了3种萃取头、4种萃取温度、4种萃取时间分析较好的萃取方法。结果 3种萃取头(85μm PA、75μm CAR/PDMS、100μm PDMS)中75μm CAR/PDMS萃取效果最好;萃取温度为60℃时萃取风味成分种类最多;萃取时间为30 min比其他3个时间(10、20、40 min)的萃取效果要好。宣威火腿的风味物质分析得43种物质,其中包括醛类(10种)、酸类(14种)、醇类(6种)、烃类(5种)、酯类(5种)、酮类(3种),且醛类和酸类物质含量较高。结论 75μm CAR/PDMS萃取头,60℃萃取温度和30 min萃取时间是较佳的萃取宣威火腿风味成分的条件。     

宣威火腿加工过程中的蛋白质降解规律

采用双向凝胶电泳技术结合基质辅助激光解析电离-串联飞行时间质谱,研究了以宣威杂交猪后腿按传统工艺加工的宣威火腿在腌制前(24 h)、腌制结束(18 d)、风干结束(125 d)、成熟中期(250 d)、成熟结束(360 d)等5个阶段的股二头肌的蛋白质降解规律。也分析了组织蛋白酶在宣威火腿加工过程中的活性变化规律。研究显示,宣威火腿在各个阶段的蛋白质斑点数分别为1533、1523、1402、1196与1018个,而组织蛋白酶B和L的潜在活力在火腿加工结束时的残余活力分别为腌制前的10.25%和8.56%。可见,肌肉蛋白质在宣威火腿加工过程中存在明显的降解情况,其中成熟中期到成熟结束阶段的蛋白降解更为突出,而组织蛋白酶B和L的潜在活力在加工过程中均逐渐下降。     

微酸性电解水对宣威火腿切片杀菌效果的研究

目的研究微酸性电解水(slightly acidic electrolyzed water;SAEW)处理对云南宣威火腿切片的杀菌效果。方法将宣威火腿切片与SAEW按不同时间(2.5、5、7.5、10 min)、不同料液比(1:2、1:5、1:10 g/mL)和不同温度(25、40、60℃)进行浸泡处理,通过菌落总数变化反映其杀菌效果,并通过感官品质、颜色和硬度等指标,探讨SAEW杀菌处理对宣威火腿切片品质的影响。结果 SAEW对宣威火腿切片表面微生物有较强杀菌效果,并随处理时间的延长、料液比的增加和温度的升高,SAEW的杀菌效力不断增强。当料液比为1:10g/mL,浸泡处理10 min,火腿切片表面菌落数由最初的1.57 Log CFU/g降至0.79 Log CFU/g;随着料液比的增加,火腿切片浸泡处理10 min,表面菌落数从最初的1.57 Log CFU/g依次降至1.27、1.01和0.79 Log CFU/g;温度对SAEW杀菌有一定协同作用,随温度升高,样品表面菌落总数显著降低(P0.05);SAEW处理对火腿切片的感官品质、颜色和硬度均没有显著影响。结论 SAEW处理不仅能够有效控制火腿切片中微生物危害,还能保证其品质不被破坏,具有良好的开发潜力。     

Chemical and structural changes in lipids during the ripening of Teruel dry-cured ham

The aim of this paper is to investigate the chemical and microstructural changes in intramuscular and subcutaneous fat during the processing of Teruel dry-cured ham by gas chromatography and electron microscopy techniques. This paper will contribute to the specific characterisation of a product included in the European Union list of special quality products, and provides a new perspective for the identification of changes related to flavour development. There seems to be a relationship between the degradation of phospholipids and the increase in the free fatty acid content, especially polyunsaturated fatty acids. The microstructural changes of the adipose tissue during the process would explain the availability of the fat to the lipolitic enzymes and the contribution to the typical flavour and taste of cured ham.     

n-Alkane content of intramuscular lipids of Iberian fresh ham from different feeding systems and crossbreeding

n-Alkane content of intramuscular lipids (Biceps femoris muscle) of the Iberian pig have been determined. Thirty-four pigs, divided into four groups, based in the feeding system (Montanera, fed on acorns and pasture; and Pienso, fed on a concentrate feed) and in the genotype (Iberian pure pigs; and Iberian crossbred with Duroc 50%) were studied. n-Alkane content of intramuscular lipids has not been affected by neither crossbreeding nor feeding, although the analysis of feeds administered to the pigs showed greater n-alkane values in pasture (consumed by animals in montanera), than in acorns and concentrate feed.     

传统宣威火腿害虫的分布与综合防治

本文综述了传统宣威火腿加工过程中害虫对火腿的危害、种类及分布情况并提出了综合防治措施。     

宣威火腿中微生物优势菌群的研究

本文主要介绍了国内外学者对著名干腌火腿中微生物的研究,特别介绍了宣威火腿中优势微生物的研究,旨在引起广大科技研究者对宣威火腿的重视,为宣威火腿的发展营造一个更为广阔的空间。     

火腿与白牛肝菌复合风味基料工艺研究

为生产火腿、白牛肝菌复合风味基料提供科学依据。以云南宣威火腿、白牛肝菌边角料为原材,以感官评分为指标,研究热反应制备复合风味基料的最佳工艺条件,在单因素实验基础上采用正交实验优化。实验表明,木糖添加量为3%,温度为110℃,时间为50 min,pH为5.5,配以其他添加物反应后,风味基料呈红棕色,香气纯正浓郁,火腿白牛肝菌特有香味突出,口感鲜美醇厚,回味浓,黏度适中,均匀透明,无杂质沉淀,感官评分88.78分。      

Effect of a high dose of CLA in finishing pig diets on fat deposition and fatty acid composition in intramuscular fat and other fat depots

Sixteen gilts were fed a control (4% of sunflower oil) or an experimental diet (4% conjugated linoleic acid (CLA) oil). CLA had no effect on intramuscular fat (IMF) content neither in longissimus thoracis (LT) nor in semimembranosus (SM) muscles but increased liver weight, reduced perirenal fat and tended to reduce backfat between the last 3th–4th lumbar vertebrae. Despite the fact that 9c,11t and 10t,12c CLA isomers were included in the same proportion in the diet, the 9c,11t and 9c,11c were the isomers more deposited in all tissues. Addition of CLA in the diet affected fatty acid composition in a tissue specific manner, increasing percentages of SFA in all tissues, reducing percentages of MUFA in LT and LT subcutaneous fat, and of PUFA in LT subcutaneous fat, liver and SM. The FA modification by dietary CLA in LT IMF was reflected in the different lipid fractions, SFA and MUFA mainly in the neutral lipid fraction, and PUFA in the polar fraction.     

宣威火腿生产加工中HACCP的应用研究

为了提高宣威火腿产品质量和安全性,该文对宣威火腿生产中可能产生的影响产品质量的危害(HA)进行分析,找出生产过程控制的关键点(CCP),并确定各CCP的控制标准、监控程序和纠偏措施,将生产加工过程中危害因素降到最低限度     

宣威火腿加工过程中抗氧化肽活性变化规律

以不同加工阶段的宣威火腿为原料,研究宣威火腿中多肽的含量及其抗氧化活性变化规律。以同浓度谷胱甘肽(GSH)作为对照,分别用1,1-二苯基-2-三硝基苯肼(DPPH)自由基、羟自由基、超氧自由基清除率以及总抗氧化能力对多肽抗氧化活性进行评价。结果显示:多肽含量及抗氧化活性随加工时间增加呈现出逐渐提高的趋势,且加工0~2个月和6~8个月的火腿中肽含量和抗氧化活性有显著性提高(p<0.05)。除清除超氧自由基能力外,其他抗氧化能力均低于GSH(p<0.05)。以上结果表明,随着加工时间的增加,宣威火腿中多肽含量呈增加趋势,多肽的抗氧化活性在加工0~2个月和6~8个月增加更加明显。     

宣威火腿加工过程中生物胺变化规律

用40条重量在9～11 kg的原料腿按照传统工艺加工宣威火腿,分别在腌制前(24 h)、腌制结束(18d)、风干结束(125 d)、成熟中期(250 d)与成熟结束(360 d)这5个加工阶段随机取出5条火腿,以股二头肌为中心取约100 g样品,以HPLC方法测定生物胺含量。结果表明,宣威火腿样品中共检测出7种生物胺,分别是色胺、苯乙胺、腐胺、酪胺、尸胺、亚精胺和精胺。在各个加工阶段,精胺的含量都是最高的,其次是酪胺与亚精胺。酪胺、亚精胺与精胺的含量在5个加工阶段都没有显著变化(P>0.05)。苯乙胺与腐胺含量显著增加(P<0.05),在成熟中期(250 d)时达最高值,随后含量有所降低(P>0.05)。生物胺总量随着加工过程的进行有所增加,在成熟中期(250 d)达最大值11.51mg/100 g,随后生物胺总量有降低的趋势,但差异不显著(P>0.05)。     

宣威火腿与金华火腿中游离脂肪酸组成比较分析

以两年宣威火腿和金华火腿为对象,采用气相色谱-质谱联用法(GC-MS)分别对宣威火腿和金华火腿的皮下和肌内脂肪中游离脂肪酸的组成进行分析。结果表明:宣威火腿和金华火腿的肌内脂肪和皮下脂肪中均检测出22种游离脂肪酸,含量较高的脂肪酸为棕榈酸(C16:0)、硬脂酸(C18:0)、油酸(C18:1n9c)与亚油酸(C18:2n6c),且不同火腿及不同部位间的脂肪酸组成含量存在明显差异;金华火腿肌内及皮下脂肪中总游离脂肪酸含量分别为29.24、102.68 μg/mg,分别比宣威火腿高34.58%(p<0.05)、29.09%(p>0.05);宣威火腿和金华火腿肌内脂肪中饱和脂肪酸含量高于不饱和脂肪酸含量,皮下脂肪中不饱和脂肪酸含量高于饱和脂肪酸含量。金华火腿肌内、皮下游离脂肪酸含量均高于宣威火腿相应部位游离脂肪酸含量。