不同滚揉腌制工艺处理对猪肉腌制过程中色泽的影响

滚揉是很多肉制品,特别是西式火腿生产过程中必不可少的一道工序,具有促进发色、加快腌制、改善质构等作用。文中通过色差仪、发色率、肌红蛋白含量的测定结合感官评定,对猪肉腌制过程中色泽受不同滚揉工艺处理的影响作了初步研究,发现猪后腿肉各项色泽指标发生了显著的变化。其中加压滚揉腌制时间比传统的真空滚揉腌制时间降低了33.3%,时间由传统的真空滚揉腌制12h缩短至加压滚揉腌制8h,使得猪后腿肉的色泽达到了传统工艺水平。     

Monitoring of nitrite and N-nitrosamine levels in irradiated pork sausage

Residual nitrite and N-nitrosamine levels were monitored on irradiated emulsion-type cooked pork sausage in aerobic or vacuum packaging states during storage. The sausage was irradiated at 0, 5, 10, and 20 kGy and stored at 4 degrees C for 4 weeks. The residual nitrite levels were significantly reduced by gamma irradiation (P < 0.05), whereas the vacuum packaging was more effective for nitrite reduction than aerobic packaging during storage. N-nitrosodimethylamine (NDMA) and N-nitrosopyrrolidine (NPYR) levels were significantly reduced in the vacuum packaged sausage irradiated with 20 kGy after 4 weeks. Reduction of NPYR in aerobically packaged sausage was also found after 4 weeks by irradiating with a 5-kGy or higher dose. NDMA reduction was shown in vacuum packaging and irradiation at 20 kGy. Gamma irradiation was effective in reducing the residual nitrite all throughout storage and N-nitrosamines in sausage after storage.     

茶多酚对腌制猪肉护色效果的影响

茶多酚是一种天然的食品添加剂,加入茶多酚可以减少亚硝酸钠的使用。将不同量的茶多酚添加于猪肉中进行腌制,通过颜色感官评分、pH和发色率值这些测定指标的变化,初步研究了茶多酚对腌制猪肉的护色效果。发现不同茶多酚添加量的猪肉在腌制过程中,各项指标发生了显著变化。结果表明:添加0.4 g/kg茶多酚能最高限度地提高腌肉的发色率,使其pH值更接近5.6～6.0,并能在较长时间保持较好颜色。     

Effect of nitrate and nitrite curing salts on lipolysis in dry sausages produced using a rapid fermentation process

 The effect of nitrite and nitrate curing salts on lipolysis in a typical non-smoked Spanish sausage (salchichón), manufactured using a rapid dry fermentation process, was studied. From the results obtained, one could deduce that nitrite and nitrate per se do not affect the endogenous hydrolysis of the lipids during the rapid fermentation process used to produce dry sausage. Polyunsaturated fatty acids (PUFA) are liberated in greater quantities than monounsaturated (MUFA) and saturated (SFA) ones, which suggests that they are derived mainly from phospholipids. The samples that contained nitrate curing salts contained more free fatty acids (FFA) (548 mg/100 g) than those that contained nitrite curing salts (478 mg/100 g) at the end of the fermentation step, as a consequence of having undergone a preripening stage, during which significant amounts of FFA are formed. However, at the end of the ripening process, although there is a significant increase of FFA levels in all the sausages, no significant differences between samples with nitrite and those with nitrate could be found. This result could have occurred if the oxidative effects of the samples with nitrate balanced the antioxidative properties of nitrite, such that, through different processes, similar concentrations of FFA are obtained at the end of ripening. Phospholipids (PL) and free fatty acids (FFA) are the lipid fractions that undergo the most important changes during ripening. PL are moderately degraded during the drying process, probably due to the combined effects of the drying temperature (10°C) and the presence of starters. However, this degradation does not differ significantly between the samples that contain nitrite and and those that contain nitrate in each control. Received: 23 July 1997 / Revised version: 8 October 1997     

Effect of nitrate and nitrite curing salts on lipolysis in dry sausages produced using a rapid fermentation process

 The effect of nitrite and nitrate curing salts on lipolysis in a typical non-smoked Spanish sausage (salchichón), manufactured using a rapid dry fermentation process, was studied. From the results obtained, one could deduce that nitrite and nitrate per se do not affect the endogenous hydrolysis of the lipids during the rapid fermentation process used to produce dry sausage. Polyunsaturated fatty acids (PUFA) are liberated in greater quantities than monounsaturated (MUFA) and saturated (SFA) ones, which suggests that they are derived mainly from phospholipids. The samples that contained nitrate curing salts contained more free fatty acids (FFA) (548 mg/100 g) than those that contained nitrite curing salts (478 mg/100 g) at the end of the fermentation step, as a consequence of having undergone a preripening stage, during which significant amounts of FFA are formed. However, at the end of the ripening process, although there is a significant increase of FFA levels in all the sausages, no significant differences between samples with nitrite and those with nitrate could be found. This result could have occurred if the oxidative effects of the samples with nitrate balanced the antioxidative properties of nitrite, such that, through different processes, similar concentrations of FFA are obtained at the end of ripening. Phospholipids (PL) and free fatty acids (FFA) are the lipid fractions that undergo the most important changes during ripening. PL are moderately degraded during the drying process, probably due to the combined effects of the drying temperature (10°C) and the presence of starters. However, this degradation does not differ significantly between the samples that contain nitrite and and those that contain nitrate in each control. Received: 23 July 1997 / Revised version: 8 October 1997     

超声波对猪肉腌制效率及其品质特性的影响

研究了超声波处理(UC)对猪肉腌制效率、品质特性及微观结构的作用效果。结果表明:UC频率40k Hz、功率40 W处理60 min,能显著提高腌制剂的渗透效率和猪肉的系水力,获得较好的色泽和质构;UC辅助腌制1 d可达干腌(DC)9 d、湿腌(WP)6 d的腌制效果;在微观结构上,UC导致肌纤维断裂、弯曲等变化,对线粒体也具有明显的破坏作用。UC辅助腌制能显著提高猪肉的腌制效率和产品品质。     

Effect of salt and sodium nitrite on growth and enterotoxin production of Staphylococcus aureus during the production of air-dried fresh pork sausage

Staphylococcus aureus contamination and enterotoxin production is a potential food safety hazard during the drying step of production of air-dried fresh country sausage. The growth characteristics and enterotoxin production of S. aureus during the drying step of this product with and without added sodium nitrite were evaluated. Three strains of S. aureus were grown to stationary phase and inoculated (10(4) CFU/g) into sausage ingredients. Fresh pork sausages were stuffed into natural casings and allowed to dry for 10 days at 21 degrees C with 60% relative humidity (RH). In control sausage (1.76% [wt/wt] salt) with no S. aureus, aerobic plate counts increased by 5.5 log/g during the 10-day drying period, and coliforms increased by 4.8 log/g. The addition of sodium nitrite (154 ppm of nitrite, 2.24% [wt/wt] salt) or increased salt (3.64%, wt/wt) to sausage limited the growth of coliform bacteria (P < 0.05). S. aureus numbers increased approximately 2 log units during the drying step, regardless of additional salt or nitrite. Additional salt or nitrite had no effect on S. aureus growth (P > 0.05). Staphylococcal enterotoxin (SE) was not detected in air-dried fresh sausages at any time. Our results suggest that drying of fresh pork sausage under similar parameters listed in this study does not support SE production.     

优质香料烟品种杰尼克及其栽培技术要点

优质香料烟品种杰尼克是1996年从土耳其引进的,在湖北省十堰市经过4年的试验示范,于1999年2月通过了由中国烟草总公司组织的科技成果鉴定。鉴定认为杰尼克适应十堰地区的生态条件,具有典型的优质沙姆逊类型香料烟的特征特性,有生产国际水平优质沙姆逊型香料烟的潜力;杰尼克品种引种试验成果在国内同类研究中达领先水平,适宜在湖北十堰地区及条件类似的香料烟产区推广应用。1 杰尼克品种的主要特征特性1．1 植物学特征及农艺性状1．1．1 成苗期性状 苗高11．0 cm,茎围1．0 cm,叶数7片,苗色浅绿至绿,长势中等,主根长3．8 cm,侧根…     

白肋烟调制期间主要化学成分变化趋势初探

研究了白助烟调制期间主要化学成分烟碱、总氮、蛋白质、还原糖、钾、镁、钙含量的变化趋势。晾制开始阶段是烟碱相对含量增加较多的时期,结束前有所闰少。晾制期间,总氮和蛋白质相对含量总的趋势是持续下降。氮碱比变为不适宜时期是调制前期,应在这一时期采取措施调节其比值。还原糖含量的变化趋势是变黄期和干盘期迅速减少。晾制期间钾含量略有增加。     

Time-dependent depletion of nitrite in pork/beef and chicken meat products and its effect on nitrite intake estimation

The food additive nitrite (E249, E250) is commonly used in meat curing as a food preservation method. Because of potential negative health effects of nitrite, its use is strictly regulated. In an earlier study we have shown that the calculated intake of nitrite in children can exceed the acceptable daily intake (ADI) when conversion from dietary nitrate to nitrite is included. This study examined time-dependent changes in nitrite levels in four Swedish meat products frequently eaten by children: pork/beef sausage, liver paté and two types of chicken sausage, and how the production process, storage and also boiling (e.g., simmering in salted water) and frying affect the initial added nitrite level. The results showed a steep decrease in nitrite level between the point of addition to the product and the first sampling of the product 24 h later. After this time, residual nitrite levels continued to decrease, but much more slowly, until the recommended use-by date. Interestingly, this continuing decrease in nitrite was much smaller in the chicken products than in the pork/beef products. In a pilot study on pork/beef sausage, we found no effects of boiling on residual nitrite levels, but frying decreased nitrite levels by 50%. In scenarios of time-dependent depletion of nitrite using the data obtained for sausages to represent all cured meat products and including conversion from dietary nitrate, calculated nitrite intake in 4-year-old children generally exceeded the ADI. Moreover, the actual intake of nitrite from cured meat is dependent on the type of meat source, with a higher residual nitrite levels in chicken products compared with pork/beef products. This may result in increased nitrite exposure among consumers shifting their consumption pattern of processed meats from red to white meat products.     

不同腌制方式对猪肉腌制速率及肉质的影响

为缩短腌制时间,降低生产成本,指导腊肉的快速腌制,以常压液腌为对照,探讨了常压滚揉,真空滚揉、脉动真空滚揉3种腌制方式对猪肉p H值、腌制液吸收百分比、蒸煮损失、剪切力和食盐含量的影响。结果显示,4种腌制方式下,猪肉的p H值总体呈上升趋势,但相邻检测点间差异不显著(p>0.05);脉动真空滚揉、真空滚揉与常压滚揉的腌制液吸收百分比高于常压液腌,其中脉动真空滚揉腌制的腌制液吸收百分比最大;脉动真空滚揉腌制后的蒸煮损失与剪切力跟其他3种腌制方式相比最小;在达到相同的食盐含量时,脉动真空滚揉腌制所需要的时间最短。结果表明,脉动真空滚揉腌制猪肉效果较好。     

Effect of curing agents on m-calpain activity throughout the curing process

Curing of ham involves a number of biochemical reactions, mainly related to lipolytic and proteolytic enzymes that contribute to the development of taste and flavour. Calpains are calcium-dependent enzymes that are known for their proteolytic activity in the first stages of meat tenderisation during postmortem storage. However, their activity in longer processing and in the presence of curing agents remains unclear. This study shows that the curing agents and process parameters have an important effect on m-calpain activity. This enzyme is activated with increasing concentrations of NaCl, obtaining a maximum at 0.34 M NaCl. Activation is also promoted by the addition of sucrose. In contrast, ascorbic acid, phosphates and particularly polyphosphates promote enzyme inhibition. Finally, calpain activity is not affected by nitrates and levels of water activity higher than 97%. Therefore, a careful selection of curing agent concentrations and process parameters is required for these types of processes, since the proteolytic activity is greatly affected and, as a consequence, the resulting tenderness and flavour of the final cured product.     

不同晾制阶段白肋烟主要化学成分的变化

对白肋烟晾制过程中主要化学成分的变化进行了初步研究。结果表明，白肋烟晾制过程中烟叶的糖分、总氮、蛋白质含量呈减少趋势；而烟碱和钙的含量呈增加趋势。这种减少或增加的程度以凋萎期和变黄期变化幅度最大。     

Stability of red food colours in the presence of nitrite in canned pork luncheon meat

The stability of nine red food colours in pork luncheon meat products in the absence and presence of nitrite has been investigated. The extracted dyes were examined by visible and u.v. spectrophotometry and paper chromatography for changes due to processing and to the presence of nitrite. All the colours were destroyed to some extent but with nitrite more of the food colour survived. Subsidiary dye components and colourless fluorescent products were formed as a result of heat processing and in certain cases additional products were observed in the presence of nitrite.     

传统腌腊制品中亚硝酸盐的危害及其替代物的研究进展

亚硝酸盐是一种传统的发色剂,能赋予肉制品诱人的色泽,对肉毒梭状芽孢杆菌有抑制作用,并且有助于肉制品风味的产生和保持。但亚硝酸盐添加过量能引起中毒,同时又是强致癌物N-亚硝胺的前体物。腌腊制品在生产上需保证良好的色泽及安全性,完全不添加亚硝酸盐几乎是不可能的,应尽可能降低亚硝酸盐的使用量并积极寻找高效、安全的替代物。本文介绍了腌腊制品中亚硝酸盐替代物的研究进展,由于微生物制品迎合了人们要求食品天然化,不加或少加化学添加剂的愿望,因此本文对天然微生物制品替代亚硝酸盐进行了着重介绍。最后本文还对未来减少食品中亚硝酸盐危害的研究方向进行了展望。     

Evaluation of the thermal resistance of different Salmonella serotypes in pork meat containing curing additives

The preliminary heat resistance evaluation of 94 Salmonella strains was carried out in culture medium (Trypticase soy broth, TSB). The heat resistance of three S. typhimurium strains (ATCC 14028, 133 and 1116), a strain each of S. derby B4373, S. potsdam 1133, S. menston 179. S. eppendorf 166, and S. kingston I124 was determined also in pork meat containing curing additives. As expected, the eight Salmonella strains showed greater heat resistance in pork meat than in TSB. At the lowest temperature (58 degrees C), the heat resistance increased 1.5-4 times, and it was most pronounced for the strains being most heat sensitive in TSB. S. potsdam 133 was the most resistant strain in pork meat, with D-values at 58 degrees C, 60 degrees C and 63 degrees C of 4.80, 1.57 and 0.30 min, respectively. The most sensitive strain turned out to be S. kingston 1124, with D-values of 2.79. 0.92 and 0.24 min, at the same temperatures. According to collected data, the heating processes, as applied to cured pork meat, providing an internal temperature of 60 degrees C for 9-10 min or of 63 degrees C for 3-4 min can be expected to provide a > or = 7 D kill of Salmonella belonging to the serotypes studied.     

制糖生产过程中亚硝酸盐的控制

甜菜中含有微量的亚硝酸盐和大量的氨氮化物,渗出过程中亚硝化菌将大量的氮氧化物分解成亚硝酸盐。通过控制渗出器一段温度或者添加药物可大幅度减少过程中的亚硝酸盐产生。结晶过程中良好的结晶操作,可减少不良晶粒的产生,使亚硝酸尽可能留在母液中而不进入晶粒中或停留在不良晶粒的表面。通过这两个方面作用确保成品白砂糖的亚硝酸盐指标合格。     

香肠中次磷酸钠复合添加剂替代亚硝酸钠的研究

研究制备新型次磷酸钠复合添加剂(由次磷酸钠、丁基羟基茴香醚、胭脂虫红以不同配比组成),与亚硝酸钠在香肠中的作用做比较,以研究替代可行性。结果表明:复合添加剂第4组(次磷酸钠3000 mg/kg、丁基羟基茴香醚30 mg/kg、胭脂虫红0.015%)在颜色感官评价、抑制肉毒毒素能力、抗氧化能力与亚硝酸盐相当,并且在质构结构、抑制微生物方面优于亚硝酸钠。因此,次磷酸钠复合添加剂对香肠品质有较好效果。