米发糕贮藏期内水分变化与老化关系的研究

以早籼米为原料,米发糕贮藏过程中的水分变化为研究对象,在不同的贮藏方式下,研究了米发糕芯部硬度、表层硬度与质量和贮藏时间之间的相互关系.结果表明,米发糕在室温25℃贮藏48 h后,表层硬度在第7 h后开始发生急剧增加,而其芯部硬度在第19 h才开始出现急剧增加现象,直接贮藏的米发糕芯部和表层硬度的增加幅度显著大于用保鲜袋贮藏的米发糕硬度增幅.水分丧失是米发糕质量下降的重要原因,米发糕的芯部硬度、表层硬度分别与重量和贮藏时间有显著相关性.     

The Effect of Fat Replacers on Batter and Cake Properties

Fat was replaced at 35% to 100% in cakes by maltodextrin (dextrose equivalent = 3), inulin (high performance and granulated), oligofructose, citrus pectin, and microparticulated protein. Fat replacement by 35% did not induce significant differences in general. Above 65% fat replacement resulted in statistically significant (P < 0.05) decreased viscosity (except for pectin) that was followed by statistically significant decrease in air incorporation and broader bubble size distribution. The starch gelatinization temperature showed a statistically significant increase when fat was replaced by fructose oligosaccharides. The cakes presented statistically significant increase of hardness, elasticity, and decrease of volume development as fat replacement increased above 65%. Also cakes with increased fat replacement received lower scores on taste and flavor, whereas at total fat replacement they were evaluated as not acceptable. Nevertheless, at 65% fat replacement, the samples presented acceptable textural, physical, and sensorial attributes.     

不同藜麦粉添加量对海绵蛋糕面糊特性及烘焙特性的影响

为提高无麸质蛋糕的品质,通过测定不同藜麦粉添加量的面糊的流变特性和密度;蛋糕的比容、烘焙损失率、色差、感官评分以及贮藏7 d后蛋糕的质构特性、水分分布和老化焓值等指标,探究藜麦粉对无麸质面糊特性及蛋糕品质的影响。结果表明,面糊的弹性模量（G′）、黏性模量（G″）和密度与藜麦粉添加量呈正相关,进而增大了蛋糕比容并降低烘焙损失率,蛋糕气孔分布更加均匀。高比例的藜麦粉（30%～50%）能有效延缓蛋糕的老化。在贮藏7 d后,对照组和50%藜麦粉老化焓值分别增加至1.42 J/g和0.92 J/g。综上,添加藜麦粉能够显著提高面糊的流变特性和蛋糕的烘焙特性,延缓蛋糕老化。综合蛋糕感官评分和老化特性,藜麦粉添加量为30%时较为适宜,可以赋予无麸质海绵蛋糕更好的品质。     

米粉品种和粒度对蛋糕糊力学特性及成品品质的影响

为探究米粉品种和粒度对蛋糕糊力学特性及成品品质的影响,以粳米、籼米和糯米为研究对象,分别制备80,100,120,140目的米粉,分析蛋糕糊的质构、基础流变学特性以及蛋糕成品的质构特性、感官品质。结果表明,随粒度减小,损伤淀粉含量呈增加趋势,其中140目的糯米粉中损伤淀粉含量最大为23.1%。蛋糕糊的动态流变学结果表明,所有蛋糕糊的弹性均大于黏性,均表现出类似半固体的行为,初步判定为黏弹性流体。籼米粉和粳米粉蛋糕糊的G’值均高于糯米粉,G″值均低于糯米粉;随米粉颗粒粒度减小（80～140目）,籼米粉和粳米粉,蛋糕糊的G’增加,G″减小,而糯米粉相反。蛋糕糊的大形变质构特性结果表明,粳米粉、籼米粉、小麦粉蛋糕糊的弹性及回复性随粒度的减小而增大,黏聚性随粒度的减小而减小,而糯米粉蛋糕糊与之相反。蛋糕的质构结果表明,米粉粒度减小,蛋糕的硬度增大;米粉蛋糕的硬度与小麦粉蛋糕相比,整体上偏高,其中籼米粉蛋糕的硬度显著高于小麦粉和其它品种。感官分析粒度为120目的粳米粉评分最高。弹性模量与蛋白质和直链淀粉含量分别呈显著正相关和极显著正相关,与损伤淀粉含量呈显著负相关,黏性模量与直链淀粉含量呈极显著...     

鸡肉火腿肠贮藏期间应力松弛特性及质地评价

研究鸡肉火腿肠贮藏期间应力松弛特性、TPA质地参数变化规律.结果表明:贮藏时间对阻尼体黏滞系数η影响不显著,对其余3个松弛参数影响均极显著;在10℃和5℃条件下,贮藏温度对4个松弛参数影响均不显著.贮藏时间对硬度和耐咀性有较为显著的影响,对内聚性和弹性影响不显著;贮藏温度对4个TPA质地参数的影响是不显著的.在整个贮藏过程中,鸡肉火腿肠的质地没有发生较大的变化,仍保持较好的食用品质.经高温处理,鸡肉火腿肠松弛特性显著降低,其质地变得更加柔软、易嚼.     

黑芝麻蛋糕配方优化及质构特性研究

研究黑芝麻粉、蛋白中糖的添加量、以及低筋面粉和玉米淀粉的比例对黑芝麻蛋糕产品质量综合评分的影响,在单因素试验的基础上,以感官得分为响应值,通过Box-Behnken中心组合设计原理和响应面分析法,对黑芝麻蛋糕的配方进行优化。确定其最佳配方参数为:黑芝麻26 g,低筋面粉38 g,玉米淀粉9g,蛋白中白砂糖36 g,鸡蛋120 g,塔塔粉1 g,盐1 g,色拉油18 g,水32 g,蛋黄中白砂糖20 g,在此配方下黑芝麻蛋糕感官评分可达90.89。建立感官得分与质构特性之间的线性回归模型为Y=103.064-1.96a+2.21b-2.216c-17.382d。     

不同因素对马铃薯千层饼质构的影响

为拓展马铃薯在主食中的应用,采用马铃薯鲜薯制备烘焙型马铃薯千层饼。分析配方（马铃薯、酵母和泡打粉）、发酵条件（温度、时间和湿度）和烘焙条件（时间和温度）等因素对千层饼的硬度、胶着度和咀嚼度等质地剖面分析（texture profile analysis,TPA）指标的影响。结果表明,随着马铃薯、酵母和泡打粉添加量增大,千层饼的TPA指标降低;随着发酵温度和发酵湿度的升高,马铃薯千层饼的TPA指标先降低再升高;随着发酵时间延长,马铃薯千层饼的TPA指标先升高再降低;随着烘焙温度的升高和烘焙时间的延长,马铃薯千层饼的TPA指标升高。     

桑葚无糖天使蛋糕的制作工艺优化及质构性质分析

为拓宽桑葚的应用同时满足大众对新型焙烤食品的需求,制作无糖低脂、低热量、无明显蛋腥味且适口的天使蛋糕,本试验采用单因素和响应面试验研究桑葚果汁、木糖醇、蛋清和低筋面粉的添加量以及焙烤温度和时间对天使蛋糕感官品质和硬度的影响,以优化制作工艺;同时为考察桑葚果汁的添加对蛋糕质构性质的影响,测定了相同储藏条件下桑葚无糖天使蛋糕与普通天使蛋糕的质构性质。结果表明:蛋糕的最优制作工艺是:低筋面粉45 g,桑葚果汁33 g,木糖醇45 g,蛋清135 g,塔塔粉3 g、柠檬汁2 g,牛奶30 g,焙烤温度为上火165 ℃,下火150 ℃,焙烤时间为35 min,在此条件下桑葚天使蛋糕的感官评分为91.8分。对蛋糕进行质构分析,得出桑葚果汁的添加可显著降低蛋糕的硬度和咀嚼性（P<0.05）,持水性增强且口感更柔软,结构紧实不松散。     

大米品种特性与米发糕质构特性的相关性研究

为选择适宜的发糕生产原料,确定发糕生产中的原料选择指标,对10种大米的品种特性及其加工的发糕的质构特性进行了研究,并对二者之间的相关性进行了探讨,确立了发糕的原料标准。结果表明：发糕原料大米的选择可以用直链淀粉含量、降落值和回生值作为选择指标。其中,大米直链淀粉含量对发糕成品品质影响最大,与硬度和回复性显著正相关,与咀嚼度极显著正相关。     

海绵蛋糕复合乳化剂研究

在海绵蛋糕中加入单甘油酯、蔗糖酯、硬酯酰乳酸钙(CSL)及Tween-80等乳化剂均能提高蛋糕品质,通过正交试验研究不同配比乳化剂对提高海绵蛋糕感官品质和保鲜性不同作用,其中蛋糕保鲜性通过测定蛋糕水分活度变化和感官变化加以判断;试验结果表明,海绵蛋糕乳化剂最佳工艺配方为:单甘油酯0．2％、蔗糖酯0．2％、硬酯酰乳酸钙(CSL)0．4％、Tween-80为0．1％。     

不同温度及包装方式下复合杂粮米发糕的储藏特性

本文以高筋小麦粉为主要原料,黑米、小米、燕麦等杂粮为添加物,制成一种新型复合杂粮米发糕,研究杂粮米发糕贮藏过程中的品质变化。分别用塑料盒和真空袋两种包装方式,在设定的温度下(-18℃冷冻、4℃冷藏、25℃室温)储藏米发糕,定期测定样品水分含量、菌落总数及比容,在复蒸后测定质构特性,从而对杂粮米发糕品质变化的原因及其变化机理做了分析。结果表明:随着贮藏时间的延长,杂粮米发糕的菌落总数、咀嚼性、硬度上升,而水分含量、弹性、回复性下降。经对比分析,使用真空包装在-18℃条件下保存,杂粮米糕水分损失率小,菌落总数增长缓慢,质构特征较初始状态差异小,是保存杂粮米发糕的最佳条件。     

Influence of Gluten-free Flours and their Mixtures on Batter Properties and Bread Quality

Gluten is a major component of some cereals and is responsible for flour technological characteristics to make bakery products. However, gluten must be eliminated from the diet of celiac patients because its ingestion causes serious intestinal damage. The objectives of this study were to assess the effect of different flours and their mixtures on thermal and pasting properties of batters, and to study the quality parameters and staling rate of gluten-free breads. Starch gelatinization temperatures and enthalpies depended on batter composition. Soy flour addition had a higher effect on rice than on corn starch, indicating some differential interaction between starch and proteins. Inactive soy flour incorporation improved all bread quality parameters in both corn- and rice-based breads. Higher batter firmness of formulations with soy addition (extrusion force was doubled in rice/soy and rice/corn/soy batters with regard to rice and rice/corn batters) partially explained higher specific volume (rice breads: 1.98 cm³/g; rice/soy 90:10 2.51 cm³/g, corn/soy 90:10: 2.05 cm³/g, whereas corn/soy 80:20: 2.12 cm³/g), as these batters retained more air during proofing. The staling rate was decreased by soy flour incorporation on rice (staling rate of rice breads with 10% soy diminished 52%, and with 20% of soy addition, 77%, both regarding to 100% rice breads) and corn formulation (the staling rate of corn/soy 80:20 breads was 5.9% lower than corn/soy 90:10) because of the high water-holding capacity of soy proteins and the interactions established with amylopectin that could retard the retrogradation process. Breads made with rice, corn, and soy flours showed the best quality attributes: high volume, good crumb appearance, soft texture, and low staling rate.     

Hot-stage Microscopy of Cake Batter Bubbles during Simulated Baking: Sucrose Replacement by Polydextrose

A hot-stage video microscopical technique was developed to study the effects of sucrose replacement by polydextrose (weight for weight basis) on the foam characteristics of cake batters, before and during heating. Polydextrose substitution increased the mean size of air-bubbles in the cake batter and introduced a larger variation in bubble size distribution than the sucrose batter. The differences between sucrose and polydextrose batters on initial bubble size distribution were reflected in expansion rates of bubble populations during heating. The lack of uniformity in the bubble distribution of batters containing polydextrose increased the rate of gas diffusion from small bubbles to larger ones. On heating, the bubble population of sucrose batters expanded more than that of polydextrose substituted batters.     

米发糕的储藏品质研究

以大米为原料,采用专用发酵剂制作米发糕,研究包装方式和温度对米发糕储藏品质的影响,为方便型米发糕的工业化生产提供技术参数。结果表明,储藏温度、包装方式对米发糕储藏品质有显著影响。储藏过程中米发糕菌落总数上升,结晶度、硬度、咀嚼度增加,弹性、黏聚性和水分含量降低,导致感官品质下降。CO2气调包装后低温度储藏有利于抑制水分损失和细菌繁殖,米发糕于-18℃储藏,菌落总数、水分变化缓慢。-18℃储藏米发糕的结晶度小于4℃储藏时的结晶度。气调包装有利于保持米发糕的质构特征。米发糕采用CO2气调包装后于-18℃储藏,使米发糕的保质期可达10天以上。     

Effect of Loading Position and Storage Duration on the Textural Properties of Eggplant

Eggplant has a very limited shelf life and, like other vegetables, is susceptible to different types of damage during and after harvest operations. Besides, eggplant is inhomogeneous considering its inner construction point of view. It is therefore important to specify how storage might affect their mechanical properties and how they vary in morphology. In this work, eggplants were divided into three portions along the longitudinal axis and their textural properties were separately investigated using different types of test over a 10-day period of storage. The results showed that the tension strength, rupture force and Young’s modulus of skin tissue decreased with increasing the length of storage period, and they were generally different in the different portions of the fruit that were sampled. The values of Young’s modulus and rupture force of pulp tissue taken from compression tests decreased from 1.466 to 0.821 MPa and 20.70 to 17.66 N for upper section, 0.637 to 0.536 MPa and 15.33 to 13.13 N for middle section and 0.518 to 0.422 MPa and 14.19 to 12.19 N for bottom section, respectively, with the increase in storage period. Similarly, as the samples were stored longer, the Young’s modulus and rupture force of their combined skin and pulp tissues, obtained from penetration tests, decreased from 3.01 to 2.02 MPa and 31.21 to 24.95 N for upper section, 2.59 to 1.66 MPa and 28.64 to 21.66 N for middle section and 1.91 to 1.15 MPa and 23.18 to 17.37 N for bottom section, respectively.     

传统海绵蛋糕配方及工艺优化研究

通过单因素实验和正交试验,确定海绵蛋糕的最佳配方及工艺:鸡蛋220 g、细砂糖90 g、蛋糕油5 g、低筋面粉100g、液态酥油25 g,以上火180℃、下火160℃烘烤16 min.在此条件下制作的海绵蛋糕色泽金黄、质地松软、组织细腻、品质最佳.     

米发糕储藏过程中微生物分析

米发糕是中国传统发酵食品,在我国尤其是南方地区颇受消费者欢迎。本实验利用16S rDNA 基因序列的PCR 扩增技术对米发糕在室温储藏过程分离出的菌株进行鉴定。结果表明：细菌是致使米发糕迅速腐败的主要因素,分离出的3 株菌经鉴定分别为发酵乳杆菌、巴氏葡萄球菌和蜡样芽胞杆菌。对米发糕腐败菌的菌相变化进行分析,确定乳杆菌和芽孢杆菌是米发糕储藏过程中的优势腐败菌,且都随着时间的延长呈明显上升趋势。