低盐川味腊肉的研制与加工

在传统腊肉加工的基础上,采用新型的腊肉加工工艺,筛选含盐量低、产品风味和口感较好的川味腊肉。产品选取优质五花肉为主要原料,添加各种香辛料而制成。结果表明：通过正交优化配方试验分析,确定添加2．5％食盐、1．0％花椒和I．5％辣椒,产品具有较好的川式腊肉的风味和口感。水分含量均控制在25％上下。食盐添加量为2．5％时,腊肉产品的氯化物含量（以干基计）为5．13％,有效降低腊肉氯化物含量,亚硝酸钠的残留量在20mg／kg以下,在我国国家准标范围之内。     

食盐用量对四川腊肉加工及贮藏过程中肌肉蛋白质降解的影响

以不同食盐用量（食盐用量分别为原料肉质量的3%、4%、5%、6%、7%,用A、B、C、D、E来表示）腌制的四川腊肉为研究对象,分析了肌肉中非蛋白氮（non-protein nitrogen,NPN）、游离氨基酸（free amino acids,FAA）含量以及肌浆蛋白和肌原纤维蛋白在加工贮藏过程中随时间变化的规律。结果显示：A、B、C组NPN含量较高;C组FAA含量最高,含量最高时达到11.75 mg/g;肌浆蛋白、肌原纤维蛋白在腊肉的腌制期和烟熏期大量降解,而肌原纤维蛋白的降解主要集中在分子质量大于99 kD的区域,A、B、C组的两种蛋白变化趋势一致,D、E组一致。结果表明：食盐用量会抑制蛋白质的降解,当食盐用量为肉质量的5%时,最有利于游离氨基酸的生成,并且腊肉中较低的食盐用量会缩短贮藏阶段肌浆蛋白含量达到最大值的时间,却延缓了肌原纤维蛋白含量达到最大值的时间。     

外源蛋白酶对黔式腊肉风味的影响

在黔式腊肉加工过程中,通过注射添加木瓜蛋白酶和中性蛋白酶,促进蛋白质降解,以利于风味物质的形成.结果表明:黔式腊肉最优酶解条件为木瓜蛋白酶添加量0.001％、中性蛋白酶添加量0.001％、食盐添加量4％、酶解时间48h;添加蛋白酶样品中非蛋白氮(NPN)、氨基态氮(AN)、挥发性盐基氮(TVBN)的含量以及游离氨基酸(FAA)种类和总量均高于未加酶样品;经GC-MS检测,添加蛋白酶样品中有65种挥发性风味物质,比未添加蛋白酶样品多10种,风味物质种类除烃类和羰基类化合物外,都有所增加,烃类、酚类和醇类相对含量增加,酯类相对含量减少.     

传统腊肉低温熏烤过程中脂质氧化及物理化学、感官品质指标的变化

以重庆传统腊肉为对象,分析测定其低温熏烤加工过程中水分、酸价、过氧化值(POV)、苯并(α)芘、亚硝酸盐含量等理化指标,研究其质构特性和感官指标变化规律。结果表明：长时间低温熏烤的重庆腊肉成品水分含量较低、硬度较大,具有良好的色泽和风味;成品的酸价和过氧化值分别为3.02mg /g 脂肪、0.0273g/100g 脂肪,亚硝酸盐和苯并(α)芘含量分别为7.23mg/kg 和4.6μg/kg,均符合国家标准。长时间低温熏烤的重庆传统腊肉具有较高的食品安全性,熏烤加工的时间也有望减少到20d。     

Analysis of volatile compounds in traditional smoke-cured bacon(CSCB) with different fiber coatings using SPME

The volatile compounds of Chinese traditional smoke-cured bacon (CSCB) were studied using SPMS-GC/MS. There were 48 volatile compounds identified and quantified, which belonged to several classes of chemical: 1 alkane, 16 aldehydes, 5 ketones, 9 alcohols, 4 thioethers and thiols, 3 furans and 10 phenols compounds. All the volatile compounds except for alkane was responsible for CSCB characteristic flavor. The major volatile compounds of CSCB came from smoking, oxidation and Maillard reaction, etc. Many volatile compounds were not reported in previous paper isolated by steam distillation method or nitrogen purge-and-steam distillation method on CSCB. It should be because of different method of isolating volatile substances from CSCB. Among the fibers tested, CAR/PDMS (carboxen/polydimethylsiloxane) fiber coating showed the highest area counts for most volatile compounds. CAR/PDMS coating extracted better those compounds whose linear retention indices (LRI) was lower than 926 (on average) and DVB/CAR/PDMS (divinylbenzene/carboxen/polydimethylsiloxane) those with higher LRI.     

Effect of fat score on the quality of various meat products

In the larger Swiss abattoirs the fat score (FS) is determined by default as an indicator of fat quality. The FS refers to the iodine number and is related to the degree of unsaturation of the outer layer of backfat. In a feeding trial with Large White gilts, the FS was determined in 47 carcasses. Meat and fat tissues were prepared for the production of salami (SAL), raw-cured bacon (RCB), pork hamburger (PHB) and Vienna sausage (VIS). In the different meat products, the FS was closely related to the percentage of saturated (SFA: r = −0.49 to −0.79) and polyunsaturated fatty acids (PUFA, r = 0.36 to 0.79) for RCB, SAL and PHB (p ? 0.05), but not for VIS. For RCB, significant correlations with FS were seen for the meat:fat-ratio (r = 0.39), fat firmness (r = −0.31) and one fat oxidation marker (1-octen-3-ol: r = 0.51). The texture (r = −0.60), a_w-value (r = 0.63) and one fat oxidation marker (1-octen-3-ol: r = 0.46) were significantly correlated with FS in SAL. On the whole, only a few variables correlated significantly with FS for SAL and RCB and the corresponding relationships were always linear. No significant correlation between FS and any of the technological and sensorial parameters were found for VIS or PHB.     

Heterocyclic amines and polycyclic aromatic hydrocarbons in commercial ready-to-eat meat products on UK market

Heterocyclic amines (HCAs) and polycyclic aromatic hydrocarbons (PAHs), which are developed during meat processing, may play key roles in the imposing health risk. The consumption of ready to eat (RTE) meat products has increased dramatically in recent years due to their convenience. Therefore, it is essential to evaluate its health risk and provide dietary intake guidance to the general public. 11 RTE meat products were selected from UK market including chicken, pork and fish to investigate their health risks in concern of HCAs and PAHs levels. HCAs and PAHs were extracted by solid-phase extraction and analysed by HPLC-DAD/FLU. Chargrilled chicken contained the highest amount of HCAs (37.45 ± 4.89 ng/g) and PAHs (3.11 ± 0.49 ng/g), followed by roasted bacon (HCAs 15.24 ± 1.31 ng/g, PAHs 1.75 ± 0.17 ng/g) and honey roast salmon (HCAs 17.12 ± 5.86 ng/g, PAHs 0.38 ± 0.09 ng/g). The high dietary intake of HCAs was from chargrilled chicken and ham, which could contribute to the increase in breast cancer and colorectal adenoma. While cancer risk associated with PAHs intake from RTE meat products was relatively low according to the Lifelong Average Daily Intake of UK consumers.     

不同烟熏烘烤方式对湘西腊肉挥发性成分的比较

以湖南湘西腊肉为研究对象,比较工厂快速烘烤烟熏和农家传统风干烟熏过程对湘西腊肉挥发性成分的影响。采用固相微萃取-气相色谱-质谱联用技术(SPME-GC-MS),分别对工厂快速烘烤方式的腌制结束、烘烤烟熏2 d、6 d三个阶段进行取样分析和农家传统风干烟熏的腌制结束、烟熏5 d、15 d、30 d后四个阶段的腊肉进行取样分析,比较两种加工方式成品挥发性成分的差别。在工厂和农家加工过程中分别鉴定出73种和76种挥发性成分,分析得出湘西腊肉大致挥发性成分为酯类、酸类、醛类、酮类、酚类和烃类。工厂加工腊肉成品中主体挥发性成分是酚类、醛类和烃类,其相对含量分别为62.50%、8.95%和5.08%;农家加工腊肉成品中主要挥发性成分有酚类、酯类和烃类,其相对含量分别为14.80%、0.91%和0.68%。工厂加工成品的挥发性成分在种类和相对含量上均高于农家加工成品。     

不同类型烟熏香精对西式培根风味的影响

为研究不同类型烟熏香精对西式培根风味的影响,本研究通过感官评价和电子鼻技术对添加不同类型烟熏香精制作的西式培根进行整体风味的分析,利用固相微萃取气相色谱-质谱联用技术研究不同类型烟熏香精对西式培根挥发性风味物质的影响。结果表明,不同类型烟熏香精制作的西式培根与传统西式培根在整体风味和主体风味化合物上进行比较,乐香水溶性烟熏香精（样品5）差异最小,其次为名花烟熏膏香精（样品1）和奇华顿油溶性烟熏香精（样品3）,再次为红箭油溶性烟熏香精（样品2）,而红箭水溶性烟熏香精（样品4）差异最大。乐香水溶性烟熏香精制作的西式培根与传统西式培根（对照样）的挥发性风味物质比较接近,有愈创木酚、4-甲基愈创木酚、苯酚和2,6-二甲基苯酚等35种共有成分。其中酚类物质的种类和传统西式培根相同,而含量是传统的1.22倍,从宏观和微观上都可以达到传统西式培根的风味。