酶法提取金华火腿中的风味前体物质

采用Protamex和Flavourzyme酶组合水解金华火腿制备提取物,尽可能提取金华火腿中的风味前体物质.利用单因素和响应面分析法优化了双酶组合的作用条件,实验结果表明较佳的工艺条件为:料水比1:7,反应温度50℃,初始pH7.5,同时加入两种酶,两酶的添加量分别为:Protamex 1.6%,Flavourzme 5.0%,作用时间为110 min.此时,总氮回收率为86.9%,蛋白质水解度DH为24.1%,滋味评分50,气味评分49,与响应面分析得到的回归方程中的理论值基本一致.产品风味较佳,富含游离氨基酸.     

全麦胚粉对复合火腿肠品质特性的影响

研究探讨了全麦胚粉在猪肉火腿肠中的应用特性及对产品品质的影响,通过正交试验进行了配方优化,对优选配方产品的部分特性——感官、质构和水分指标进行了分析。试验优选出的复合麦胚火腿肠主配方为瘦肉/肥膘比92∶8、麦胚12.5%、淀粉18%、水20%。全麦胚粉的添加能明显增加火腿肠的硬度、胶着性和咀嚼度,复合产品的风味独特、组织结构和质地良好。     

Decolouration and lipid oxidation changes of vacuum-packed Iberian dry-cured loin treated with E-beam irradiation (5 kGy and 10 kGy) during refrigerated storage

The effect of irradiation (0, 5 and 10 kGy) on the oxidative and colour stability of vacuum-packed Iberian dry-cured loin slices from pigs fed on concentrate feed (CON) or free-range reared (FRG) stored under refrigerated storage was studied. Irradiation treatment increased lipid oxidation, measured as TBA-RS values and hexanal content of dry-cured loins. It also increased redness (CIE a) and lightness (CIE L) of dry-cured loins. Refrigerated storage reduced the differences due to irradiation treatment of instrumental colour values like lightness. However, the decrease of redness during storage was more marked in irradiated than in non-irradiated dry-cured loin. Storage increased differences in TBA-RS values between irradiated and non-irradiated FRG dry-cured loin, while the opposite trend was found for CON dry-cured loins. In addition, no differences in the hexanal content were found after 30 days of refrigerated storage. Therefore, the storage of Iberian dry-cured loin in absence of oxygen by using a vacuum packaging could be an adequate method to reduce changes associated to irradiation treatment in Iberian dry-cured loin.

Industrial relevance

Iberian dry-cured loin is a high sensory quality meat product with increasing projection in external markets Irradiation has shown to be an effective method to control pathogen and spoilage microorganisms in meat and meat products. However, e-beam irradiation can promote colour and oxidation changes that could modify their sensory characteristics. The study aimed the evaluation of e-beam irradiation at two levels (5 and 10 kGy) — higher doses than those that could be necessary to control pathogen microorganisms in this kind of product — on colour changes and lipid oxidation at vacuum-packed slices of Iberian dry-cured loin during subsequent extended chilled storage. E-beam treatment induced changes in colour and lipid oxidation in sliced Iberian dry-cured loin immediately after treatment and subsequent refrigerated storage.     

Investigating quality attributes and consumer acceptance of uncured, no-nitrate/nitrite-added commercial hams, bacons, and frankfurters

ABSTRACT:  Increasing demands for natural, organic, and/or preservative-free foods have resulted in the consumer availability of uncured, no-nitrate/nitrite-added processed meat and poultry products. A comprehensive understanding about the quality and sensory attributes of commercially available uncured products is unclear. The objective of this study was to determine if quality and sensory differences exist between uncured and cured meat products. Five different commercial brands (Brands A to E; 4 uncured, no-nitrate/nitrite-added, and 1 nitrite-added) of 3 product types (hams, frankfurters, and bacons) were obtained from retail supermarkets. The samples were evaluated for color, pigment content, pH, lipid oxidation, residual nitrate and nitrite content, and consumer acceptance. All brands from all product types evaluated, except for 1 bacon (Brand B), had cured color, aroma, and flavor attributes similar to the nitrite-added control (Brand E). All product types and brands contained residual nitrate and residual nitrite except for Brands B and D bacons (< 1 ppm nitrite). Lipid oxidation as measured by 2-thiobarbituric acid reactive substances revealed a large variation in the occurrence of lipid oxidation both between and within product types, with frankfurters reporting the highest levels. Color measurements indicated the majority of the brands within each product type were similar to the control. Consumer sensory ratings for surface/lean color, aroma, flavor, texture, and overall acceptance determined that variation existed. Brand E (nitrite-added control) and 1 uncured, no-nitrate/nitrite-added brand for each product type were not different ( P > 0.05) for overall acceptance and received higher scores ( P < 0.05) than all other brands within each product type.     

Bind, Sensory and Chemical Properties of Restructured Dry-cured Hams

Restructured, boneless, dry-cured ham product was processed from intact, bone-in, dry-cured hams (DC). Processing variables included tumbling and addition of ground, dry-cured ham meat. Restructured treatments were more tender (P<0.05), less salty (P<0.01), and had less off-flavors (P<0.05) with similar country ham flavor compared to the DC control. Addition of ground meat decreased tenderness (P<0.05) and increased Instron binding values. Tumbling decreased off flavors (P<0.05). Sensory bind scores of restructured hams were greater (P<0.05) than fresh, restructured controls (FR); however, Instron binding values were higher (P<0.001) for FR. An acceptable restructured product could be made from traditionally processed dry-cured hams.     

现代滚揉腌制工艺对低盐火腿风干成熟中品质变化的影响

本研究以猪后腿为原料,采用现代滚揉腌制及风干成熟工艺加工低盐火腿,并分析滚揉腌制对火腿半膜肌及股二头肌品质的影响。结果表明,现代滚揉腌制对火腿理化品质有显著的影响(p<0.05),具体表现为半膜肌中水分含量显著高于对照组(p<0.05),股二头肌中实验组水分含量显著低于对照组(p<0.05),食盐含量显著高于对照组(p<0.05),半膜肌和股二头肌中水分及盐分含量差异较小,在火腿风干成熟过程中,滚揉腌制对火腿色差L*、a*、b*变化趋势影响较小;与对照组相比,滚揉腌制能显著降低半膜肌和股二头肌的硬度(p<0.05),显著改善了火腿的质构特性。并且对半膜肌和股二头肌中游离脂肪酸重量、蛋白质水解指数及感官品质无显著影响(p>0.05)。因此,现代滚揉腌制能平衡火腿半膜肌及股二头肌的理化品质,促进产品的内外部位品质的稳定性。      

PRKAG3 and CAST genetic polymorphisms and quality traits of dry-cured hams - I. Associations in Spanish dry-cured ham Jamón Serrano

The functional single polymorphisms identified in the calpastatin (CAST) gene have been related to the rate of meat tenderization and the protein turnover after slaughter, and the Ile199Val polymorphism identified in the coding region of the protein kinase AMP-activated (PRKAG3) gene has been proven to affect ultimate pH in muscle. The aim of the present study was to show the effects of these genetic polymorphisms on the quality traits of Spanish dry-cured ham Jamón Serrano. A tissue sample from 665 crossbreed pigs were genotyped for PRKAG3 Ile199Val, CAST Arg249Lys and CAST Ser638Arg polymorphisms, and a subsample of 120 dry cured hams was selected to perform physico-chemical, rheological, instrumental colour and sensory analyses. Associations between the polymorphisms and several quality traits of dry-cured ham, mainly related to flavour and texture, were found. The genotypes PRKAG3 Ile/Ile, CAST249 Arg/Arg and CAST638 Arg/Arg, and the haplotype CAST 249Arg-638Arg were the most favourable for Jamón Serrano production.     

Solubility and absorption rate of carbon dioxide into non-respiring foods. Part 3: Cooked meat products

The solubility and diffusion of carbon dioxide into cooked meat products (cooked ham and meat sausage with different pH-levels) was determined at different starting pressures and gas to product volume ratios by monitoring pressure changes over time in a closed chamber at constant temperatures (0, 4, and 8 °C). Good correlation of the CO₂ solubility between the packaging parameters (gas to product volume ratio and initial partial pressure) and the meat products water content was found. The solubility of CO₂ followed Henry’s law and the initial partial pressure of CO₂ influenced the solubility mostly. Only small variations in the diffusion constants and absorption rates were found within the experimental design. A pH difference of 0.5 in the two meat sausage types did not influence either solubility or diffusion significantly.     

Phenotypic correlations among quality traits of fresh and dry-cured hams

In this study, fresh and processing quality traits were collected on a total of 312 Country Hams. Phenotypic correlations between traits were estimated and numerous values were significantly different (P<0.05) from zero. Yield was significantly correlated with several fresh pork quality traits measured on the fresh hams, including subjective color (0.34) and lipid percentage (0.32). Some meat color traits were significantly correlated, including associations between the color scores taken on the fresh and cured hams. Correlations between fresh pork quality traits were also determined, with results showing significant correlations between ultimate pH and other pork quality traits. The results indicate that yield can be maximized if hams with good fresh pork quality parameters are used for curing. The correlations estimates are helpful for understanding of the biological mechanisms behind the production of dry-cured hams and can potentially be used to improve the efficiency of the dry-cured ham production chain.     

金华火腿香精的调配

借助顶空固相微萃取法,研究并确定了煮熟后金华火腿的香气核心成分,配合调香师的调香技艺,模拟调配出适合市场需要的金华火腿咸味香精,可为市场上的金华火腿调味料提供低成本技术支持。