响应面法优化冷冻面团馒头冷冻工艺

为确定冷冻面团馒头最佳冷冻工艺参数,在单因素试验基础上,选择冷冻时间,冷冻温度为自变量,馒头感官评分、馒头比容、馒头硬度为响应值,利用Box-Benhnken中心组合试验和响应面分析法,研究各自变量及其交互作用对冷冻面团馒头感官评分、比容、硬度的影响。通过回归分析和响应面曲面图,得到最优工艺参数并进行验证试验。结果表明,冷冻温度为-30℃,冷冻时间为30 min时,馒头感官评分(85.2分)、比容(2.45 cm3/g)及硬度(485.47 g/kg)均达到最佳值。     

海藻酸钠对冷冻面团面包烘焙特性的影响

研究添加不同比例(0.1%、0.3%、0.5%和0.7%)海藻酸钠对冷冻面团面包烘焙特性的影响。结果表明,添加海藻酸钠能提高冷冻面团的持水率,减少冷冻面团醒发时间;增大面包的比容,降低面包的硬度和咀嚼性,提高弹性,改善冷冻面团面包的品质。感官评定显示,冻藏不同天数后,添加0.3%的海藻酸钠面包感官评分值最高。     

木聚糖酶对冷冻面团和馒头品质的影响

本实验研究了木聚糖酶对冻藏1d、7d、14d的冷冻面团和馒头品质特性的影响;并采用差示量热扫描仪(DSC)测定了冷冻面团的可冻结水(冰)含量,讨论了木聚糖酶改善冷冻面团品质的热力学机制。研究结果表明,随着冻藏时间的延长,面团的发酵力、酵母存活率、馒头比容、抗老化能力均呈现一定的下降趋势;在相同的冻藏时间下,木聚糖酶对面团的发酵特性和馒头品质改善作用明显;木聚糖酶含量为80mg.kg_-1时,可冻结水(冰)含量最低;添加木聚糖酶后,冰晶颗粒更加细小均匀。这说明适量的木聚糖酶能够有效地降解水不溶性阿拉伯木聚糖,使更多的水分保留在面筋网络结构中,从而抑制低温面筋网络结构和酵母细胞的破坏作用,改善馒头品质。     

冷冻速率对面团发酵和烘焙性质的影响

研究了冷冻速率对冷冻面团体系中酵母发酵(包括酵母产气力、酵母存活率)和面团微结构的影响;以及对冷冻面团烘焙性质的影响(包括面包比容,面包评分和面包保质期).结果显示冷冻速率同时影响酵母活力和面团的超微结构,进而影响面包的品质和体积,综合考虑,确定面团在-32℃下快速冷冻至-18℃(冷冻速率约-5℃/min),并在-18℃下冻藏,较适合冷冻面团的生产.     

乳化剂影响新鲜及冷冻面团面包品质的研究

研究了硬酯酰乳酸钠(SSL)、卵磷脂、单甘酯、蔗糖酯、双乙酰酒石酸甘油酯(DATEM)等几种面包加工常用乳化剂对新鲜面团及冷冻面团的力学特性及面包的质构和感官品质的影响。结果表明,乳化剂的添加会显著提高新鲜面团的力学特性和新鲜面团面包的感官品质,卵磷脂为最适乳化剂,适宜添加量为0.45%(面粉为基数);乳化剂对冷冻面团的力学特性的影响不显著,但可以显著改善冷冻面团面包感官品质,SSL为最适乳化剂,适宜添加量为0.30%(面粉为基数)。     

Effect of black rice flour with different particle sizes on frozen dough and steamed bread quality

This article presents a novel idea for the preparation of frozen dough and steamed bread by which black rice flour (BRF) with different particle sizes (0.18–0.25 mm, 0.15–0.18 mm and 0.125–0.15 mm) was added into wheat flour (WF), considering the nutritional values of BRF. The characteristic of the composite flour (CF), frozen dough and steamed bread was studied. CF had higher contents of dietary fibres (2.01–2.16%) but lower content of protein (11.57–11.92%) compared with WF (1.6% and 12.60%, respectively). Correlation analysis showed that the addition of BRF could alleviate the damage to dough caused by freezing, which may be due to that water in CF dough was more stable. The content of freezable water in WF dough increased by 23.48%, while that in CF dough increased by 6.09–12.11% after frozen storage. With decreasing particle size, the hardness of CF dough decreased and the resistance to extension and gas retention coefficient increased, whereas the specific volume and the soft crumb texture of CF steamed bread increased. In short, small-sized BRF is more suitable for use in the preparation of steamed bread.     

Effects of green tea extract on the quality of bread made from unfrozen and frozen dough processes

Two different green tea extracts (GTE‐A and ‐B) as a rich source of tea catechins were incorporated into a no‐time bread‐making process, where bread made from the unfrozen and frozen dough processes was compared by specific volume and texture profile. GTE‐A and ‐B both exhibited significant effects on bread volume and firmness, but to a different extent. GTE‐A with higher content of tea catechins (73%) at a level of 1.5 g kg^?1 flour was found to lead to a significant reduction in bread volume in unfrozen dough process and an increment in firmness during storage for 4 days at ambient temperature (22 °C). GTE‐B, with a lower content of catechins (60%), had relatively mild effects on the bread quality. Significantly negative effects were evident starting at a higher level of 5.0 g kg^?1 flour in unfrozen dough process. Frozen storage showed more predominant deteriorating effects than the GTEs over a period of 9 weeks frozen storage at ?20 °C. Copyright © 2006 Society of Chemical Industry     

抗冻蛋白对预发酵冷冻面团发酵流变特性和馒头品质的影响

运用F4发酵流变仪、质构仪等研究冻藏和冻融循环下抗冻蛋白对预醒发冷冻面团发酵流变学特性和馒头品质的影响。结果表明:随着冻藏时间的延长和冻融循环次数的增加,冷冻面团馒头的比容减小,硬度和咀嚼性明显增大,弹性和回复性下降。冷冻面团的最大发酵高度、气体总释放量和气体释放最大高度均明显下降。说明冻藏和冻融循环严重影响了酵母的产气能力和面团的持气性,与冻藏和冻融循环过程中重结晶和大冰晶的形成有关。添加抗冻蛋白的冷冻面团馒头品质得到明显改善,说明抗冻蛋白能够减缓冷冻面团馒头冻藏和冻融循环过程中品质下降。     

影响冷冻面团质量的因素

主要探讨了冷冻面团加工过程中工艺流程的选择、冻结前的处理、冻结条件,冻藏条件和解冻方法对冷冻面团质量的影响以及冷冻面团加工中基本原料的选择和添加剂的种类对面团质量的影响。     

预醒发酵子冷冻面团馒头发酵工艺的优化研究

为了确定酵子冷冻面团馒头最佳发酵工艺,首先研究了预醒发时间对冷冻面团馒头品质的影响,在单因素试验的基础上,选取酵子添加量、加水量、发酵温度、发酵时间进行了4因素3水平的正交试验,确定了酵子冷冻面团馒头的最佳发酵工艺。结果表明:预醒发时间60 min时,冷冻面团的外观较好,成品馒头的感官总分最高;各因素对馒头感官品质的影响顺序为:发酵时间>加水量>发酵温度>酵子添加量,酵子冷冻面团馒头的最佳发酵工艺为:酵子添加量8 g、加水量50 m L、发酵温度35℃、发酵时间135 min。对照试验中,酵子冷冻面团馒头感官总分比酵母冷冻面团馒头高,酵子冷冻面团馒头与新鲜馒头相比,新鲜馒头感官总分较高。     

南方馒头冷冻面团生产技术研究

该试验开展了南方馒头冷冻面团生产技术的研究,重点探讨了加糖量、酵母添加量、发酵温度和发酵时间等因素对冷冻面团生产的南方馒头的感官评分、硬度、比容等品质指标的影响,并采取响应面法建立了上述工艺参数对冷冻面团生产的南方馒头品质影响的数学模型。结果表明,南方馒头冷冻面团生产的最佳发酵工艺为：发酵温度35 ℃,加糖量8.2%,酵母添加量1.0%,发酵时间41 min。在此最佳条件下,冷冻面团生产的南方馒头感官评分达79.7分,硬度805.26 g,比容2.98 mL/g。     

冻结和冻藏对冷冻面团流变学以及汤包皮质构特性的影响

研究了冻结温度、冻藏温度、冻藏时间对冷冻面团流变学特性和汤包皮质构特性的影响。实验结果表明,冻结改变了面团的流变性质,降低了面团的弹性;并且-18℃下冻结对汤包皮TPA参数的影响比-30℃的影响大。-30℃的冻藏温度对面团的粘弹性影响较大,而不同冻藏温度对汤包皮的TPA参数影响不大;冻藏时间对面团粘弹性、面团拉伸特性以及汤包皮的TPA参数影响大。     

面包面团玻璃化贮存与非玻璃化贮存的品质比较

面包面团分别贮存在家用冰箱(-18℃,非玻璃态贮存)和超低温冰箱(-88℃,玻璃态贮存)中,采用质构仪分析面团在贮存0、7、30、90 d后的面团质构特性,并测定面包比体积。结果表明:(1)非玻璃态贮存面团的黏度、延展性先升高后降低,变化幅度大,而面团弹性、弹性恢复比快速下降;(2)玻璃态贮存面团的黏度、延展性先降低,而后缓慢升高,面团弹性随贮存时间小幅下降、弹性恢复比基本无变化;(3)面包比体积变化情况与面团弹性变化情况相似,说明面团的弹性能较好地反映面包的比体积。玻璃态贮存可以降低重结晶反应速率,减少大冰晶生成,降低面团在贮存过程中的面筋网络破坏;可以降低面团中水分活性,减小水分迁移速率,防止淀粉过度水化。     

Influence of guar gum on the baking quality of gluten-free cheese bread made using frozen and chilled dough

The aim of the study was to assess the effect of guar gum on the quality and textural properties of gluten-free (GF) cheese bread made using chilled and frozen GF cheese dough. The guar gum addition was at 3.5% (G3.5), 4% (G4) and 4.5% (G4.5) levels, based on the weight of the cheese in the product. Samples of frozen dough with 3.5% guar gum and of chilled dough with 4.5% guar gum were chosen for sensory analysis as they had the closest hardness and specific volume to samples of fresh dough and dough without guar gum (Control). The overall consumer acceptance of samples that had been processed using freezing treatment presented the lowest liking score due to the light salty taste.     

混合试验仪确定冷冻面团馒头复配添加剂最佳配方

利用混合试验仪研究硬酯酰乳酸钠（SSL）、黄原胶、抗坏血酸（VC）对冷冻面团特性的影响。通过单因素试验、正交试验确定了冷冻面团复配添加剂的最佳配方为SSL0.1%、VC0.010%和黄原胶0.3%。用不同复配添加剂配方制作冷冻面团馒头,利用感官品质评分、质构品质测定进行综合评价,最佳结果与Mixolab试验结果一致。     

冷冻面团馒头关键工艺技术研究

以提高冷冻面团馒头品质为目标,研究了加水量、酵母添加量及解冻时间等关键工艺参数对冷冻面团馒头比容、扩展比等感官品质以及硬度、咀嚼度等质构品质的影响。研究结果表明,冷冻面团馒头的制备采用一次发酵法,酵母添加量为1.0%,加水量为50mL,和面时间控制在5min内;然后将面团在-40℃速冻35min,再将面团转移至-20℃的冰箱中储存7d后解冻,当解冻湿度控制在75%、解冻温度为30℃,解冻时间为60min时,蒸制的馒头质构和感官品质最好。     

响应面法优化酵母冷冻面团馒头生产工艺

为了确定酵母冷冻面团馒头的最佳生产工艺,选取酵母添加量、加水量、发酵温度、发酵时间进行试验。在单因素的基础上,进行Box-Behnken中心组合研究,建立了对酵母冷冻面团馒头感官总分影响的数学模型,确定了酵母冷冻面团馒头的最佳生产工艺。结果表明,各因素对酵母冷冻面团馒头感官总分的影响顺序为:发酵温度酵母添加量发酵时间加水量。最佳工艺条件为:酵母添加量1.2 g、加水量51.2 m L、发酵温度35.7℃、发酵时间43.7 min,在此条件下预期的酵母冷冻面团馒头感官总分是76.8分,实际感官评价得分为76分。     

冷冻面团制作的面包在储存期间风味的变化

在冷冻甜面团的研究开发中,通过感官评价小组采用描述性分析对面包样品的风味剖析,同时采用固相微萃取(SPME)技术分别提取样品中的挥发性风味物质,并经气相色谱-质谱(GC-MS)联用法进行鉴定,重点研究了冷冻甜面团在不同冷冻储存阶段所制作的面包的风味变化问题。结果发现,用冷冻甜面团制作的面包与相同配方制得的新鲜面包相比,在冷冻期间21～28d内,烘焙风味的劣化即呈现出来并急速降级,如酸含量明显升高,醇类明显降低,醛类相对较高,酯类、呋喃类有所升高但芳香族化合物却较低,并在长达70d的冷冻储存期间趋于不可逆转的稳定状态。