熬煮牛肉汤不要超过4小时

食品研究人员的实验表明，熬煮牛肉汤时会产生一些危害人类健康的致突变性物质，这种物质的形成分为延缓期和活性期两个阶段。延缓期大约是4个小时，就是在开始熬煮牛肉汤的4小时之内，牛肉汤中没有或有很少的致突变性物质生成。4小时后为活性期，汤中逐渐有致突变物质生成，并且随着熬煮时间延长，汤汁中的致突变物质逐渐增多。所以熬煮牛肉汤不是时间越长越好。杭州商学院包开洪等人实验研究表明，牛肉汁浓度对细菌致突变性有较显著的影响。熬煮的牛肉汤汁浓度相当于每毫升中有3克绞细的瘦牛肉时，汤汁中基本没有致突变物质，而汤汁浓度再…     

不同处理牛肉预煮汁中肌肽含量与抗氧化研究

牛肉预煮汁是目前熟肉制品加工环节的主要副产物,本研究对牛肉预煮汁进行超滤和去离子两种方法处理,采用DPPH法和微生物法测定处理后牛肉预煮汁的抗氧化效果。结果显示:10～100mmol/L的肌肽标准溶液对DPPH自由基有显著的清除能力(P<0.05),肌肽标准溶液浓度与清除率呈高度正相关性r=0.9958;牛肉预煮汁对DPPH自由基具有很强的清除效果,其中,预煮牛肉汁超滤液浓度与清除率呈高度正相关性r=0.9995,而预煮牛肉汁去离子液浓度与清除率呈高度正相关性r=0.9641;从抑菌效应考察牛肉预煮汁的表观抗氧化率得出:牛肉预煮汁的表观抗氧化率随着汁液中肌肽含量的递增呈现极强的正相关性,预煮牛肉汁超滤液与表观抗氧化率相关系数达到0.9977,且预煮牛肉汁超滤液的表观抗氧化率弱于肌肽标准溶液,肌肽标准溶液的抗氧化率又弱于VC,而VC的抗氧化率弱于茶多酚。结论:牛肉预煮汁含有除肌肽以外的更丰富的抗氧化性成分,具有比纯肌肽标准溶液更好的抗氧化效果。     

牛肉肠添加海带的研究

提出了牛肉肠添加海带的3种方法(海带干粉法、海带肉汁法、海带浸提法)，并通过对比试验得出海带浸提法是牛肉肠添加海带的最佳方法。     

如何鉴别优劣食品

一、肉类(猪、牛、羊肉): 新鲜的有一种固有的香味,肉表面微有干膜,肉色淡红发光,用手指压之有弹性,肉汁透明。 不新鲜肉表面非常干燥或非常     

食尚新流行

神户牛排主料:神户牛肋排200克辅料:面包条,元葱,胡萝卜调味:广味源烧烤汁、牛肉汁各30克,BBQ烧烧酱20克,鸡粉、味精、白兰地酒各5克,黑板粒3克,香叶5片,广味源草茹老抽酱油适量制作方法: 1、先将牛肋排加元葱、胡萝卜、烧肉汁,广味源烧烤汁、牛肉汁、鸡粉、味精、白兰地酒、黑板粒、香叶、与清水一同煲酥取出; 2、把煮制好的牛排捞出晾至凉透,浇上烧烤酱,放入上下温度250度的烤箱,烤至黑背红色; 3、面包条烤金黄,放入盘中,再把烤好的牛排摆放在一起即可。口味特点:牛肉肉质酥烂,口感细腻操作关键:烤制牛排时要掌握好肉质的成熟度,注意控制火候     

烹调方法对食品致突变性的影响

利用Ames菌株TA98加S9代谢活化系统研究了烹调方法对单个食品及其由那些食品组成的膳食的体外致突变性的影响。结果表明:(1)煮制或烤制食品的致突变性较低;(2)油炸的肉食品致突变性显著增强,而烹调方法对碳水化合物丰富的食品,鲜鱼、蛋和蔬菜的致突变性没有明显的影响;(3)以单个膳食成分的致突变性为根据的膳食预测致突变性与观测致突变性十分相似,这提示各种膳食成分没有以协同方式或抑制方式的相互作用而改变按本研究中所采用的方法测得的总致突变性。     

黑米核桃糕加工工艺研究

在传统核桃糕的配方中添加黑米,制得黑米核桃糕。通过单因素和正交试验,研究熬煮温度、熬煮压力、浓缩真空度等因素对黑米核桃糕感官品质的影响,优化黑米核桃糕加工工艺。结果表明:黑米核桃糕的最优工艺为熬煮温度140℃,熬煮压力0.70 MPa,浓缩真空度0.06 MPa,此条件下黑米核桃糕的口感细腻柔糯,咀嚼性好,品质优良,感官评分为91.0。     

蛋白质热分解物的致癌性——与N0_2反应可能使其失却活性

最近研究表明,具有致突变性物质中,有相当一部分具有致癌作用。要测定这种致癌性,可以借助于细菌致突变性的简便方法。利用细菌测定致突变性的方法,以Ames法采用较广。此法创用于1974年,以后,应用这一方法的研究进展,是很引人注目的。其中以鱼、肉加热引起致突变性的事实,最早被人们注意,对于阐明引起日常食用的鱼、肉显示致突变性的原始物质也是非常关心的。     

几种酰胺类除草剂的光降解及其致突变性

对３种常见的酚胺类除草剂乙草胺、异丙甲草胺、丁草胺的光降解进行了研究,采用Ａ。ｅｓ试验方法对母体和光降解产物的致突变性进行了检验。结果表明,在紫外灯照射下。这３种除草剂的光降解均较符合一级动力学,其降解速率次序为异丙甲草胺＞乙草胺＞丁草胺。乙草胺在光降解前后均表现出无致突变性,异丙甲草胺和丁草胺本身具有致突变性,在光降解过程中异丙甲草胺未产生其它致突变性物质,而丁草胺在光降解末期表现出有其它致突变性物质产生。几种酰胺类除草剂的光降解及其致突变性@王琪全     

琯溪蜜柚果实贮藏期间果肉汁胞质地变化研究

应用质地多面分析法,研究了琯溪蜜柚果实贮藏期间果肉汁胞质地变化规律。结果表明:在5和25℃两个贮藏温度下,琯溪蜜柚果实粒化指数均随贮藏时间的延长而上升,果肉汁胞的硬度、弹性、凝聚性、胶性、咀嚼性随贮藏时间的延长而增加。经相关性分析,黏着性与其它质构参数相关性较差,硬度、弹性、凝聚性、胶性、咀嚼性两两之间呈显著正相关(R=0.723~0.983),琯溪蜜柚果实粒化指数与各项TPA参数(除黏着性)均具有较好的相关性(R=0.793~0.988)。因此,硬度、弹性、凝聚性、胶性和咀嚼性可以较好地反映果肉汁胞质地的变化,并能定量表征琯溪蜜柚果实贮藏期间果肉汁胞的粒化程度。     

Reduction of Heterocyclic Aromatic Amine Formation and Overall Mutagenicity in Fried Ground Beef Patties by Organosulfur Compounds

ABSTRACT: The effects of several organosulfur compounds on heterocyclic aromatic amine (HAA) formation and overall mutagenicity in fried ground beef patties were evaluated. The greatest inhibition of total HAA formation was achieved with diallyl disulfide (78%) and dipropyl disulfide (70%); these compounds also reduced overall mutagenicity by 75 and 65%, respectively. The addition of diallyl sulfide, allyl methyl sulfide, and allyl mercaptan also significantly ( p < 0.05) reduced mutagenicity, with reductions of 56, 43, and 30%, respectively. The addition of cysteine and cystine, however, did not reduce the mutagenicity of cooked meat, an observation confirmed by the relatively small reductions in HAA concentrations.     

Comparative mutagenicity studies on fried minced beef,grilled sausage and grilled hamburgers

The mutagenicity of the basic fractions of fried beef patties, grilled hamburgers and grilled sausages was determined in the Ames test using activation systems (S9-mix) derived from untreated and Aroclor-pretreated rats and hamsters, and from rats pretreated with 3-methylcholanthrene or phenobarbitone. In order to indicate whether the mutagenic activity was due to the presence of thermally generated amino imidazo aza-arenes of the type previously identified in heated meat products (i.e. 2-amino-3-methylimidazo[4,5-f]quinoline (IQ), 2-amino-3,4-dimethylimidazo-[4,5-f]quinoline (MeIQ) and 2-amino-3,8-dimethylimidazo[4,5-f]quin-oxaline), these compounds were assayed under the same conditions. The mutagenicity of the basic fractions of the cooked foods and of the three aza-arenes varied with the activation system used. The activation patterns of the basic fractions from fried beef and grilled sausages resembled that of IQ, whereas that of grilled hamburgers was more similar to that of MeIQ. Interestingly the total mutagenic activity of fried beef patties was greater than that of grilled hamburgers.     

牛肉菜肴中杂环胺的形成机理和抑制方法研究进展

牛肉菜肴指以牛肉为原材料烹制而成的一类即食食品。牛肉经高温处理降解生成具有一定的致癌、致突变性的杂环胺。本文阐述了两类杂环胺的分类标准及形成机理、影响杂环胺生成的因素、牛肉菜肴中杂环胺的预处理和常见检测方法、通过研究外源物质的添加和对前体物质的影响进而研究杂环胺的抑制方法,并对杂环胺研究的未来加以展望,可对牛肉菜肴烹制过程杂环胺的控制有一定的借鉴意义。     

Antioxidative/Antimicrobial effects of galangal and alpha-tocopherol in minced beef

The antioxidant and microbial stabilities of galangal (Alpinia galanga) extract in raw minced beef were examined at 4 +/- 1 degree C. Raw minced beef containing galangal extracts (0 to 0.10%, wt/wt) were prepared. Lipid oxidation during refrigerated storage was assessed by monitoring malonaldehyde formation, using the thiobarbituric acid reactive substances method. In minced beef, added galangal extract improved oxidative stability. Galangal extract at higher concentrations of 0.05% and 0.10% (wt/wt) were also found to extend the shelf-life of minced beef. Addition of alpha-tocopherol (0.02%, wt/wt) to galangal extract (0.05%, wt/wt) were observed to increase the oxidative but not the microbial stability of minced beef during the storage of 7 days. Galangal extract may prove useful in inhibiting lipid oxidation and increasing microbial stability of minced meat.     

Extraction and Activity of Carnosine, a Naturally Occurring Antioxidant in Beef Muscle

Several methods were tested to produce a carnosine-containing antioxidant extract from beef muscle. Heat treatments, ultrafiltration and demineralization decreased total iron and hemin concentrations and increased antioxidant activity of a beef extract (2:l; water:muscle). Antioxidant activity of treated extracts was affected little by freeze-drying but was increased by vacuum oven-drying. Vacuum oven-dried (VOD), demineralized, 100°C heated extract had the greatest antioxidant activity followed by VOD ultrafiltration permeate and VOD 100°C heated extract. A beef extract high in carnosine and low in prooxidants could have potential as a natural antioxidant.     

响应面法优化虫草培养的研究

利用响应面分析法,研究蔗糖、牛肉膏和pH值对虫草菌生长生物量的影响。结果表明:营养源的种类和浓度对虫草菌生物量有很大的影响,在所选用的蔗糖、葡萄糖、柠檬酸铵、淀粉和牛肉膏、蛋白胨、硫酸铵七种营养源中,蔗糖和牛肉膏最利于虫草菌的生长,浓度以2%左右为宜;当蔗糖的浓度为2.74%、牛肉膏浓度为1.86%、pH值为7.37时,虫草菌C.FFCC5124的生物量为10.2g/L。响应面试验的方差分析表明:一次项对响应值的影响很显著,其次为平方项,而交互项影响较为微弱。     

发酵牛肉调味料的研制

以瑞士乳杆菌作为发酵荆菌种研制新型发酵牛肉调味料。利用瑞士乳杆菌分泌二肽酶、三肽酶等的特性，研究了其对牛肉酶解汁口感及风味的影响。结果表明，发酵12h牛肉酶解物的苦味基本消失、肉香较浓郁；发酵18h其口感、风味均达到最佳，并在此基础上研制出了发酵牛肉调味粉。     

葡萄皮提取物协同冰鲜对牛肉的抗氧化效果

将不同量的葡萄皮提取物协同冰温保鲜对牛肉的抗氧化效果进行研究。以冷鲜牛肉为研究对象,测定贮藏期间第1、3、5、7天肉样的色差值(L*值和a*值)、滴水损失、剪切力、硫代巴比妥酸值(thiobarbituric acid-reactive substance,TBARS)及感官指标,以蒸馏水浸泡且4℃贮藏的牛肉为对照1,以蒸馏水浸泡且冰温保鲜的牛肉为对照2。结果表明:0.15%的葡萄皮提取物与冰温保鲜协同处理的牛肉贮藏第7天时具有优良的感官特性,L*值为38.16,a*值为19.92,滴水损失为0.68%,剪切力为4321 g,TBARS值为0.18 mg/kg,对冷鲜牛肉具有显著的抗氧化效果。     

迷迭香提取物对牛肉丸冻藏过程中脂肪氧化和品质特性的影噢

将不同浓度的迷迭香提取物（0、0.02%、0.04%和0.06%）添加到牛肉丸中,并以0.02%丁基羟基茴香醚（BHA）做对照,测定迷迭香处理组和对照组牛肉丸在冻藏过程中的过氧化物值（PV）、硫代巴比妥酸值（TBARS）、色差值（L*值、a*值）、保水性和质构特性,并对牛肉丸进行感官评价,考察迷迭香提取物对牛肉丸脂肪氧化和品质特性的改善作用。结果表明,迷迭香提取物可显著降低冻藏牛肉丸的PV值和TBARS值,抑制牛肉丸的脂肪氧化程度;同时,提高牛肉丸的a*值,使其保持良好的色泽;迷迭香提取物还能降低牛肉丸的蒸煮损失和解冻损失,改善牛肉丸的保水性;硬度、弹性和咀嚼性等质构特性也得到改善;感官评价结果显示,迷迭香处理组牛肉丸的感官评分较高,具有良好的感官品质。因此,迷迭香提取物具有抑制冻藏肉牛丸制品脂肪氧化和改善其食用品质的潜在应用价值。     

The pre- and post-grinding application of rosemary and its effects on lipid oxidation and color during storage of ground beef

The timing of the application of rosemary extract was evaluated as one-way of minimizing myoglobin and lipid oxidation in ground beef. In experiment 1, rosemary extract was added to beef at four different stages namely trim, cube, coarse, and fine ground beef. The beef was evaluated for color and TBARS values during 144 h of storage (4 °C). Results showed that when rosemary was added to the pre-grinding treatments of trim and cube, ground beef had the highest a^∗ values (redness), oxymyoglobin content, and lowest TBARS values at 144 h. In experiment 2, the effect of rosemary extract was evaluated on the color quality of case ready ground beef inoculated with 10⁷ CFU/g Escherichia coli. Microbial counts, color, and TBARS values were measured during 144 h of simulated storage. The results showed that both the rosemary treated samples that were inoculated and uninoculated remained redder longer and had lower TBARS values than the untreated inoculated and uninoculated controls. There was no significant inhibition of E. coli by the rosemary extract.