烤制鹌鹑蛋挥发性成分SPME条件优化

以鹌鹑蛋为原材料,研究了烤制鹌鹑蛋挥发性成分的固相微萃取(SPME)条件.通过单因素和正交实验对萃取头种类、样品萃取量、萃取时间、萃取温度以及解吸时间进行优化.结果表明,较佳的萃取条件为:DVB/CAR/PDMS萃取头,萃取时间为30min,萃取温度为65℃,样品萃取量为2g,解析时间为2min.在此条件下,检测到烤制鹌鹑蛋中的挥发性成分34种.     

响应面法优化小龙虾烤箱辅助烤制工艺

以小龙虾为研究对象,探讨烤箱烤制小龙虾的加工工艺,以腌制时间、腌制液盐含量、烤制温度和烤制时间为单因素影响因子,小龙虾的感官评分和弹性为响应值,进行响应面优化分析。然后对烤制小龙虾的营养成分和风味特征进行测定和分析,并以鲜虾和水煮虾作为对照。结果表明：经优化后的小龙虾腌制时间为30 min、腌制液盐含量12 g/100 mL、烤制温度180℃、烤制时间20 min,在此工艺条件下小龙虾的感官评分为9.08分、弹性为3.88 mm,与预测值接近,表明该烤制工艺合理有效;烤制处理条件下单不饱和脂肪酸和多不饱和脂肪酸总含量显著高于鲜虾和水煮虾;烤制之后的小龙虾必需氨基酸和风味氨基酸含量较鲜虾和水煮虾差异明显,主要表现在天冬氨酸、甘氨酸、精氨酸和亮氨酸的损失,其中精氨酸损失最大;电子舌传感器上的烤虾响应值鲜度、咸味和甜味均显著高于鲜虾和水煮虾。适当的烤制有利于虾肉营养物质的保存和鲜香味的挥发,同时有利于产品营养与风味的提高。     

玉米粉液化及糖化工艺条件优化

以玉米粉为原料,葡萄糖当量（DE）值作为评价指标,研究料液比、时间、酶添加量、温度、pH值对玉米粉液化及糖化效果的影响,采用单因素及正交试验对液化、糖化工艺参数进行优化。结果表明,将玉米粉加水配制成料液比1∶4（g∶mL）的浆料,调pH 6.2,最佳液化工艺条件为α-淀粉酶添加量8 U/g、液化温度80 ℃、液化时间60 min、液化液调pH 4.3;最佳糖化条件为糖化酶添加量250 U/g、糖化温度60 ℃、糖化时间12 h。在此最佳条件下,葡萄糖当量值达到93.1%。     

响应面法优化玉米黄粉中玉米黄素和玉米醇溶蛋白的提取工艺

采用响应面法同时优化了玉米黄粉中醇溶蛋白和玉米黄素的提取工艺。在单因素实验基础上,选取乙醇体积分数、提取温度、提取时间为影响因子,以玉米黄素和玉米醇溶蛋白质量为响应值,应用Box-behnken中心组合试验设计建立数学模型,进行响应面分析。得到提取的最优工艺条件为乙醇体积分数83.36%、提取温度62.13℃、提取时间5.79h,此条件下玉米黄素质量为420.1μg,而玉米醇溶蛋白质量为0.6165g。与响应面所得理论值418.9μg和0.6153g十分接近,玉米黄素得率和玉米醇溶蛋白提取率分别达到0.021%、79.03%。该研究为工业化提供了依据。     

温度和时间对烤羊肉中脂质氧化的影响

为研究不同烤制温度和时间对烤羊肉脂质氧化的影响,以阿勒泰羊后腿肌为原料,经不同温度和时间烤制后,分别测定各样品的酸价、过氧化值、硫代巴比妥酸值(thiobarbituric acid,TBA)及脂肪酸的组成。结果表明:随着温度升高,羊肉在烤制过程中酸价总体呈逐渐上升趋势。过氧化值及烤制30、40 min条件下TBA值总体呈先下降后上升趋势,烤制20 min条件下TBA值先上升后下降但差异不显著(P>0.05)。烤制温度和烤制时间对饱和脂肪酸和单不饱和脂肪酸影响不显著(P>0.05),对多不饱和脂肪酸影响显著(P<0.05)。结论:羊肉的烤制条件为120℃、30 min时,氧化程度较低,产品品质较好。     

响应面法优化产朊假丝酵母发酵麻疯树饼粕产蛋白饲料工艺研究

对产朊假丝酵母发酵麻疯树饼粕的工艺条件进行了单因素实验,并利用Design Expert7.0软件设计了Piackett-Burman筛选实验,筛选出玉米粉添加量、温度、接种量3个显著性影响因素,经最陡爬坡实验,利用响应面中心组合设计对显著性影响因素进行优化,得出玉米粉添加量为3.3%,温度为30.2℃,接种量为51.2%时,氨基酸态氮最高产量为125.2mg/g.     

响应面法优化预调理烤肉加工工艺

基于传统烤肉加工技术,在研究分析食盐添加量、复合磷酸盐添加量、烤制时间和烤制温度对产品质构特性和色泽影响的基础上,以硬度、弹性值和红度值的综合评分作为优化指标,采用响应面法对工艺条件进行优化。实验确定预调理烤肉的最佳工艺条件为:食盐添加量为2.5%、复合磷酸盐添加量0.3%、烤制时间24 min、烤制温度170℃,在此条件下,烤肉的硬度为5810.894 g,弹性值为0.778,红度值为23.04,综合评分为0.738,烤肉具有最佳食用品质。     

香酥兔肉烤制工艺的优化

兔肉具有极高的营养价值,烤兔肉是兔肉加工的主要形式之一,风味独特深受消费者欢迎。烤制工艺是决定烤兔肉品质的重要因素。以兔腿肉为研究对象,对烤兔肉的工艺进行优化,考察不同盐腌量、腌制时间、烤制温度、烤制时间对烤兔肉产品的色泽、质构以及感官评分的影响,并通过单因素及Box-Behnken响应面分析得出最佳工艺参数：注射腌制、盐腌量2%、腌制时间7h、烤制温度220℃、烤制时间50min。采用该工艺得到的烤兔肉产品色泽、口感与风味俱佳,且具有可操作性。本研究可为兔肉深加工提高其经济价值提供理论与实践参考。     

脱胶对浓香菜籽油苯并芘去除的影响

以苯并芘超标的浓香菜籽毛油为原料,通过单因素实验和正交实验研究低温脱胶过程中,脱胶静置时间、脱胶温度、加水量和磷酸添加量对浓香菜籽油中苯并芘去除效果的影响。结果表明,在脱胶静置时间60 min、脱胶温度20℃、加水量3%、磷酸添加量0.1%的工艺条件下,浓香菜籽油中苯并芘去除率为83%,苯并芘含量为2.04μg/kg,水分含量为0.15%,所得浓香菜籽油风味浓郁醇厚,280℃加热试验合格。     

罗非鱼鱼脯的烤制工艺

为探讨罗非鱼鱼脯在烤制条件下的品质变化规律,以罗非鱼为实验对象,对比分析了不同烤制温度和时间组合对其色泽、质构、水分迁移、微观结构等指标的影响。结果表明,随着烤制温度升高和时间延长,罗非鱼鱼脯的硬度、咀嚼性及剪切力均逐渐增加,弹性呈现下降的趋势;色泽方面,L~*值呈现下降趋势,a~*值和b~*值逐渐增加,温度过高和时间过长会对罗非鱼鱼脯色泽造成不利影响;鱼脯内部水分和水分流动性随着烤制时间的增加逐渐降低,温度过高可能导致鱼肉油脂溢出;此外,微观结构表明烤制时间15 min后肌肉纤维逐渐收缩严重,间隙增加,可能是导致其质地过硬的原因。综合各因素及感官评价结果在烤制条件140℃,15 min时,硬度咀嚼性适中,色泽鲜亮,内部水分流动性较好,微观结构下组织形态最佳,可以作为罗非鱼鱼脯合适的烤制条件。     

不同焙烤条件的烤马铃薯条品质对比

为了探究烤马铃薯条的焙烤工艺,对比分析了不同焙烤温度和时间组合下,马铃薯条的水分含量、水分状态、抗氧化性、总酚含量、风味物质、色度及质构特性的变化规律。结果表明,随着焙烤温度的升高和焙烤时间的缩短,烤马铃薯条的水分流动性和水分含量均呈现降低的趋势,硬度和咀嚼度呈现先下降后上升趋势,抗氧化性和总酚含量呈现上升的趋势;烤马铃薯条色泽逐渐加深。不同的焙烤条件组合对烤马铃薯条主要风味物质种类的影响不显著,但对风味物质含量的影响较为明显。其中160℃烤25 min条件下,马铃薯条硬度为1532.14 g;而DPPH自由基清除率为85.25%,总酚含量为279.18 mg/100 g,相对较高;且香味明显,色泽鲜亮,是比较合适的焙烤条件。该研究可为马铃薯在食用或加工中选择适宜的焙烤条件提供理论参考。     

Effect of crust temperature and water content on acrylamide formation during baking of white bread: Steam and falling temperature baking

The effect of crust temperature and water content on acrylamide formation was studied during the baking of white bread. To assess the effect of over-baking, we used a full factorial experimental design in which the baking time was increased by 5 and 10 min at each baking temperature. Additional experiments were performed with steam baking and falling temperature baking. Immediately after baking, the crust was divided into the outer and inner crust fractions, and the water content and acrylamide concentration of each fraction was measured. The outer crust had a significantly lower water content and higher acrylamide concentration than the inner crust did. Crust temperature in combination with water content had a significant effect on acrylamide formation, higher temperatures resulting in higher acrylamide concentrations. However, at very high temperatures and lower water contents, acrylamide concentration was observed to decrease, though the bread colour was then unacceptable for consumption. Steam and falling temperature baking, on the other hand, decreased the acrylamide content while producing bread crust with an acceptable colour. The lowest acrylamide values and an acceptable crust colour were produced by steam baking.     

响应面法优化青稞焙烤工艺

以青稞为原料，通过单因素试验，研究了浸泡温度、浸泡时间、焙烤温度、焙烤时间对青稞糊化率的影响，并以青稞糊化率为响应值，采用响应面法对青稞焙烤工艺进行了优化。结果表明，青稞焙烤工艺的最佳条件为浸泡温度35 ℃，浸泡时间3.5 h，焙烤温度268 ℃，焙烤时间12 min。在此优化条件下，焙烤青稞糊化率最高可达93.18%。焙烤后的青稞具有独特的香味，可用为酿酒或其他加工食品的原料。     

Modelling of coupled heat and mass transfer during a contact baking process

A mathematical model of coupled heat and mass transfer of a contact baking process is developed. In the current model formulation, a local evaporation of water is described with a reaction-diffusion approach, where a simultaneous diffusion and evaporation of water takes place. The resulting coupled model equations (unsteady state heat transfer, liquid water and water vapour) were solved using the Finite Element Method (COMSOL Multi-physics® version 3.5). During the baking process, local temperatures and overall moisture loss were measured continuously. The model - predicting temperature, liquid water content in the product and water in the vapour phase - was calibrated and partially validated using data obtained during baking of a representative food model (a pancake batter) under controlled conditions on a specially designed experimental rig. The unknown parameters in the model equations were estimated using the standard least squares method by comparing the measured with the predicted temperature profile. Good agreement was achieved between model predictions and the experimental values.     

预处理方式对米糠酵素品质的影响

为研究经超声、微波、焙烤三种方法处理米糠对发酵后米糠酵素品质的影响,本文以米糠为原料,乳酸菌和酵母为发酵菌种,首先考察了发酵时间、发酵温度、接种比例对米糠酵素中γ-氨基丁酸(GABA)含量和pH的影响,并通过正交实验确定米糠酵素的最优发酵条件;采用超声、微波、焙烤不同工艺条件处理米糠原料,比较不同预处理方式对米糠酵素品质的影响。结果表明:经验证试验确定米糠酵素最优发酵工艺条件为:发酵时间24 h、发酵温度30 ℃、乳酸菌与酵母接种比为1:2（接种量为3%）。超声预处理方法可以显著提高米糠酵素中GABA含量（P<0.05）,微波对GABA含量影响不显著（P>0.05）,焙烤显著降低GABA含量（P<0.05）;米糠在超声功率240 W处理24 h后,米糠酵素中GABA含量为2.61 g/L,是未处理的1.85倍。本文初步探讨了不同预处理方式对米糠酵素品质的影响以期为后续制备米糠酵素提供一种新思路。     

Effect of Cooking Method (Baking Compared with Frying) on Acrylamide Level of Potato Chips

ABSTRACT:  The effect of cooking method (baking compared with frying) on acrylamide level of potato chips was investigated in this study. Baking and frying experiments were conducted at 170, 180, and 190 °C using potato slices with a thickness of 1.4 mm. Raw potatoes were analyzed for reducing sugars and asparagine. Surface and internal temperatures of potato slices were monitored during the experiments to better explain the results. Fried and baked chips were analyzed for acrylamide content using an LC-MS method. The results showed that acrylamide level of potato chips prepared by frying increased with frying temperature (19.6 ng/g at 170 °C, 39 ng/g at 180 °C, and 95 ng/g at 190 °C). In baking, however, the highest acrylamide level was observed in potato chips prepared at 170 °C (47.8 ng/g at 170 °C, 19.3 ng/g at 180 °C, and 29.7 ng/g at 190 °C). The results showed that baking at 170 °C more than doubled the acrylamide amount that formed upon frying at the same temperature, whereas at 180 and 190 °C, the acrylamide levels of chips prepared by baking were lower than their fried counterparts.     

Relationship between thermomechanical properties and baking expansion of sour cassava starch (Polvilho azedo)

The factors involved in the baking expansion of native and sour cassava starch doughs were compared with those of native corn starch. Unlike corn starch dough, native and sour cassava starch doughs showed expansion properties during baking. The storage modulus E ′ decreased for cassava starch doughs before baking expansion, but remained unchanged for corn starch dough. Expansion during the baking of sour cassava starch was attributed to water vaporisation and the fluidity of starch paste. The fact that temperature and weight loss variations at adequate water contents were significantly greater for cassava than corn starch dough is indicative of the important role played by starch melting in expansion. Expansion ability could be correlated with changes in dough–crumb thermomechanical properties when close to the starch melting temperature. © 2001 Society of Chemical Industry     

焙烤小麦胚芽中α-生育酚含量的测定与分析

以小麦胚芽为样品,设定140、160、170、180、190、200℃,6个焙烤温度,每个温度按不同的焙烤时间(10、15、20min)进行焙烤,利用高效液相色谱测定其α-生育酚的浓度,并比较不同焙烤条件下麦芽中α-生育酚含量。结果:α-生育酚浓度在0.05～0.8mg/mL范围内具有良好的线性关系(R=0.9997),加标平均回收率在85.1%～103.3%之间,相对标准偏差(RSD)小于7.3%;当焙烤温度低于190℃时,焙烤时间的延长对α-生育酚的含量的影响不显著;当温度达到190℃时,焙烤时间的延长对α-生育酚的损失具有显著影响。     

淡紫拟青霉固态发酵黄芩药渣工艺优化

为了降低淡紫拟青霉（Paeciloids lilacinus）的固态发酵成本,以黄芩药渣废弃物为基质,对其培养基组成及发酵条件进行优化,并考察不同几丁质含量对菌株产几丁质酶活性的影响。结果表明,淡紫拟青霉固态发酵的最佳培养基组成为黄芩药渣20 g,玉米粉0.8 g,尿素0.02 g,含水量80%,固态发酵最佳的培养条件为培养温度28℃,接种量10%,培养时间7 d,在此优化条件下,分生孢子数可达8.98×109 CFU/g。添加0.9%几丁质时,可显著增加菌株产几丁质酶酶活性（P<0.05）。