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1.
The effects of frozen storage and initial baking time of par‐baked cake on baking loss, volume, moisture, colour and textural properties of cake obtained after thawing and rebaking were investigated. Cakes, par‐baked at 175 °C for 15, 20 and 25 min, were stored at ?18 °C for 3, 6 and 9 months. After storage, par‐baked cakes were thawed and rebaked at 175 °C for 10, 15 and 20 min. Baking loss, moisture content, L and +b colour values, firmness, gumminess and chewiness of the resulting full‐baked cakes were significantly affected by both par‐baking and frozen storage time, while specific volume, cohesiveness, springiness and resilience values were significantly affected by frozen storage time. The increase in the time of frozen storage of the par‐baked cake leads to a decrease in the quality of the rebaked cake, namely an increase of baking loss and cake crumb firmness, and a loss in the moisture content and specific volume. Moisture of cake crumb, L and +b colour values, firmness, gumminess and chewiness significantly increased as the par‐baking time increased. However, regarding baking loss, specific volume, moisture content and textural properties, 3‐month intermediate storage at ?18 °C and 20‐min initial baking time gave the best result among the cakes produced by using the two‐step baking procedure.  相似文献   

2.
The objective of this study was to determine the importance of raw material and processing variables that influence pretzel quality by utilizing a screening experiment design. Eleven variables were selected based on preliminary experiments, and a two‐level‐11‐factor (2 11 ) fractional factorial experimental design was used to screen the variables. Several responses were measured for dough before and after extrusion, for half‐baked and fully baked pretzels. These responses are important indicators of consistency and quality during pretzel processing. Results indicated that flour protein content, the amount of water added to make dough and dough mixing time were important variables influencing dough behavior. Caustic concentration affected brightness of half‐baked pretzels but did not influence the color of the final product. Baking time was the most important factor for both half‐baked product and final product qualities. The hardness of fully baked pretzels was influenced by baking time, temperature in baking oven zone 1, drying time and drying temperature. The color of final products was significantly influenced by baking time, while both baking time and drying temperature affected the moisture content of the final product. A key observation was that none of the raw material or dough processing parameters, within the range tested, influenced final pretzel quality as defined by pretzel moisture content, hardness or color.  相似文献   

3.
The effect of final baking in convection oven (FBC), microwave oven (FBM), and microwave oven with susceptor packaging material (FBMS) on partially baked (PB) frozen gluten‐free bread characteristics was investigated. Specific volume and crust color of loaves were measured at day 0. Bread moisture, water activity, and crumb and crust texture (at 15, 45, and 90 min after baking) were analyzed at day 0 and after 28 d of frozen storage (?18 °C). Volatile compounds from breads baked in convection oven or microwave oven with susceptor packaging material were also evaluated. Bread finally baked in convection oven or in microwave oven with susceptor packaging increased crust browning. Crumb and roll hardness increased with time after final baking (measured at 15, 45, 90 min) and after 28 d of frozen storage. Bread finally baked in microwave oven was the hardest, due to high water losses. At day 0, bread finally baked in convection oven had softer crumb than bread finally baked in microwave oven with susceptor packaging but, after 28 d of frozen storage, there were no differences between them. Moreover, FBC and FBMS rendered gluten‐free breads that could not be distinguished in a triangular test and had the same volatile compounds profile. In conclusion, FBMS could be an alternative to FBC.  相似文献   

4.
《Food Hydrocolloids》1988,2(6):451-466
Effects of flour quality, batter formulation and batter viscosity on baking performance of rolled ice cream cones were examined by response surface methodology. The results showed batter viscosity to be inversely related to temperature and salt and water content. An empirical relationship was developed to optimize batter viscosity by adjustment of any given combination of these factors. The variable batter viscosity due to flour quality and chlorination could, to a large extent, be controlled by adjustments of salt and other electrolytes. Control of processing conditions, including agitation speed, time and temperature, was important for maintaining batters within a given viscosity range.  相似文献   

5.
Muffins are sweet baked products highly appreciated by consumers because of their soft texture and characteristic taste. The aim of this work was to study the influence of baking conditions on muffins’ quality. Surface crust color was monitored during baking tests at oven temperatures ranging from 140 to 220 °C, and browning kinetics was modeled by means of a browning index, BI, which follows a logistic model; a joint analysis of core temperature profile and BI curve can assist in the prediction of baking time. Finally, weight loss, crust/crumb ratio, crumb and crust moisture content, porosity, crumb and global densities, and texture were measured in the already baked muffin. The water content in the crumb remains almost constant, while considerable dehydration occurs in the crust. Finally, the results showed that intermediate oven temperatures led to a more porous, aerated, and soft crumb, with intermediate textural properties.  相似文献   

6.
The influence of wheat flour partial replacement with different types of resistant starch (RS) in muffin batter rheological properties and in baked muffin height, volume and number of air bubbles was investigated. The type of RS affected the above-described properties differently. In comparison to the control batter (without RS), replacement with RS type 3 (Novelose 330 and C*Actistar) increased viscosity and viscoelasticity, at both 20 and 80 °C. On the contrary, RS type 2 (Hi-maize 260 and Novelose 240) decreased them. These differences in viscosity and viscoelasticity were related to different baking performance. The RS3 type muffins had higher height, volume and number of air bubbles than the RS2 type muffins. An increase in viscosity and elasticity of the raw batter and during the heating process favours bubble retention and stability, thus favours baking performance. However, despite the improvement provided by the RS type 3, the baking performance was still lower than in the control muffins. One feature that may contribute to the baking differences is the delay in all the RS batters in the starch gelatinization temperature.  相似文献   

7.
Capelin mince was heated and dried and the two functional properties, water holding and soluble protein, were measured as functions of time, temperature, moisture content in the mince, and rate of drying. Heating and drying reduced water holding and soluble protein. Loss of water holding started between 30 and 35°C while soluble protein was first reduced between 40 and 50°C. The effects increased with increasing time and temperature but were almost independent of moisture content in the range 30–70% water. Heat stability increased at low moisture contents. Water holding and soluble protein in dried samples were generally a little higher than in samples which were heat treated at corresponding times and temperatures.  相似文献   

8.
BACKGROUND: The effect of the baking process (microwave versus conventional oven) on some starch characteristics of pound cake was evaluated. Proximal chemical analysis, total resistant starch (RS), retrograded resistant starch (RS3), differential scanning calorimetry (DSC), and X‐ray diffraction (XRD) were evaluated. Pound cake, one of the major products of Mexico's bread industry, was selected for analysis because the high moisture and fat content in the beaten dough might reduce the quality defects often associated with microwave baking. RESULTS: Crumbs from microwave‐baked pound cakes contained lower moisture than crumbs from conventionally baked pound cake. Lower RS was observed in fresh microwave‐baked than conventionally baked pound cake. RS3 increased significantly in conventionally baked products stored for 8 days at room temperature, whereas slightly lower changes in RS3 were observed in the microwaved product. DSC revealed less gelatinisation in microwaved pound cake which is related to limited water availability during the microwave heating process. The crystallinity peaks present in conventionally baked pound cake might be associated with RS3 content; the resistant retrograded starch formed during storage, is reflected in the XRD pattern. CONCLUSION: Microwave‐baked pound cake crumbs showed less gelatinisation than conventionally baked pound cake crumbs. Copyright © 2007 Society of Chemical Industry  相似文献   

9.
Starting with a typical baker's dough, a model system was constructed in order to examine whether moisture re-distributed itself between the two principal components, gluten and starch, of crumb during ageing. Separation of the components of dough was achieved by ultra-centrifugation. It was estimated that up to 30% of the moisture associated with the gluten fraction, migrated to the starch during 120 h of storage of the baked system at 25°c. The rate of migration decreased approximately exponentially with time. Moisture from the gluten was also found to migrate to the starch during baking, but at an accelerated rate. The rate of moisture migration in the model system, both at 100 and 25°c, was consistent with a diffusion-controlled process involving migration of the gluten-released moisture to the gluten-starch interface. Experimental results show that staling of bread involves (in addition to the generally accepted retrogradation of the starch) an irreversible modification in the water structure of the gluten, leading to the formation of labile water, which becomes available for absorption by the incompletely gelatinised starch. Since the gluten forms the continuous matrix of the crumb, the modification results in a rigidification or firming process.  相似文献   

10.
Green plantain flour (GPF) was used as a functional ingredient to produce gluten‐free (GF) bread based on a flour blend of rice flour and GF wheat starch (50:50) to improve their functional properties and to increase their resistant starch (RS) content. In pretrials, an addition of up to 30% GPF provided acceptable bread quality with maximum RS content. Based on these trials, two 23 factorial screening experimental designs were applied, where water content, baking temperature and baking time of GF bread containing 30% GPF addition were optimised. The best baking conditions to achieve satisfying GF bread quality – higher loaf volume, softer crumb firmness and regular porosity structure at the highest RS content could be defined to a maximum addition of water at 160%, baking temperature of 180 °C and baking time of 90 min. The incorporation of GPF showed good potential to improve the quality of GF bread.  相似文献   

11.
为获得低含油量、色泽金黄、外壳酥脆的挂糊油炸猪肉片,采用深层油炸模型,探讨了小麦面筋蛋白对糊粉的功能特性和对挂糊油炸猪肉片外壳食用品质的影响。试验结果表明,随小麦面筋蛋白添加量的增加,糊粉的持水性和挂糊率均呈上升趋势,而糊粉的峰值黏度、最终黏度、衰减值、谷值黏度和回生值均呈明显的下降趋势。添加小麦面筋蛋白能降低制品外壳脂肪的含量。随小麦面筋蛋白的增加,制品外壳的L*值逐渐减小,a*值和b*值逐渐增大;水分含量先逐渐升高又下降;脂肪含量先降低又逐渐升高;外壳硬度越来越大,脆性越来越小。综合考虑,小麦面筋蛋白添加量在7. 5%时,制品外壳具有较好的食用品质(含油量仅为15. 50%、含水量为19. 91%,呈现诱人的金黄色,脆性较好)。本研究可为该类制品的生产加工提供参考。  相似文献   

12.
This study discusses the effect of airflow on oven temperature profiles, the internal cake temperature and the final cake quality. It was found that the presence of airflow reduced the oscillation in the oven temperature profile from 12.98–30.27% to 3.17–4.02%. The bottom of the oven chamber experienced the greatest reduction in temperature oscillation in the presence of airflow. During the second stage of baking with airflow, the heating rate was increased from 5.07 to 7.52 °C min?1 and 8.35 °C min?1 to the increase of the baking temperature from 160 to 170 °C and 180 °C, respectively. The cake volume expansion rate was also increased 5–10% during second stage when baking with airflow condition. The cakes baked in the presence of airflow had a more porous crumb texture and lower moisture content compared to the cakes baked without airflow.  相似文献   

13.
 Response surface methodology was used to optimize the formulation of microwave-baked cakes. The independent variables were water content, emulsifier content baking time, oven power, shortening content and starch type. The quality factors evaluated were specific gravity of batter and volume index, uniformity index and tenderness of the crumb. Constraints for quality factors were obtained by conventional baking of American Association of Cereal Chemists high-ratio cake formulation. Multiple contour plots showed the optimum region for various water and shortening combinations at different emulsifier, time and power levels. Cakes formulated with wheat starch, containing 0.3% polysorbate 60, 133.7% water and 45.2% shortening (flour substitute basis), baked for 6 min at 100% power yielded acceptable cakes that can compete with conventionally baked cakes. Rice and corn cakes had lower quality than conventionally baked high-ratio cakes. Power was found to be the most efficient independent variable affecting all the dependent variables. Received: 26 August 1999 / Revised version: 11 October 1999  相似文献   

14.
Starches were isolated from near-isoline pairs of 1B/1R translocation wheats and their parents for determination of water binding capacity, swelling power, solubility, Amylograph viscosity, scanning electron microscopy, differential scanning calorimetry and bread baking characteristics. Translocation wheats had a statistically lower starch yield. The starches of these wheats had a lower swelling power at 60° and 80° and a reduction in Brabender viscosity after a 15 min holding period when compared with control starches. Texture scores of breads baked with starches from translocation wheats were better than those of control breads.  相似文献   

15.
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。  相似文献   

16.
Moisture migration largely impacts cake crumb firmness during storage at ambient temperature. To study the importance of phenomena other than crumb to crust moisture migration and to exclude moisture and temperature gradients during baking, crustless cakes were baked using an electrical resistance oven (ERO). Cake crumb firming was evaluated by texture analysis. First, ERO cakes with properties similar to those baked conventionally were produced. Cake batter moisture content (MC) was adjusted to ensure complete starch gelatinisation in the baking process. In cakes baked conventionally, most of the increase in crumb firmness during storage was caused by moisture migration. Proton nuclear magnetic resonance (1H NMR) showed that the population containing protons of crystalline starch grew during cake storage. These and differential scanning calorimetry (DSC) data pointed to only limited amylopectin retrogradation. The limited increase in amylopectin retrogradation during cake storage cannot solely account for the significant firming of ERO cakes and, hence, other phenomena are involved in cake firming.  相似文献   

17.
BACKGROUND: Anthocyanins, pink to purple water‐soluble flavonoids, are naturally occurring pigments with claimed health benefits. However, they are sensitive to degradation by high pH, light and temperature. Blue corn (maize) contains high levels of anthocyanins. Cookies are popular snacks and might serve as a vehicle to deliver antioxidants. A cookie formula with a high level of blue corn was developed with added acidulents and baked in ovens with different heat transfer coefficients. RESULTS: The best whole‐grain blue corn flour/wheat pastry flour ratio (80:20 w/w), guar gum level (10 g kg?1, flour weight basis) and water level (215 g kg?1, flour weight basis) were determined based on response surface methodology analysis. The interactions of citric and lactic acids and glucono‐δ‐lactone with three oven types having different heat transfer coefficients (impingement oven 179 °C/4 min, reel oven 204 °C/10 min and convection oven 182 °C/4 min) influenced the total anthocyanin content (TAC) remaining in blue corn‐containing cookies after baking. CONCLUSION: Cookies baked with citric acid in the convection oven retained the maximum TAC (227 ± 3 mg kg?1). By baking rapidly at lower temperatures and adding acidulents, it may be possible to increase residual natural source antioxidants in baked foods. Copyright © 2010 Society of Chemical Industry  相似文献   

18.
The effects of recipe compositions in terms of leavening agent (ammonium and sodium bicarbonates) and sugars (sucrose and glucose), and baking conditions (temperature and time) on HMF formation in cookies were studied. Five recipes were prepared by varying the types of leavening agent and sugar. The cookies were baked at different temperatures (180, 200, 210 and 220 °C) for different time (10, 15, 20 and 25 min) to monitor physical and chemical changes in cookie composition in terms of water activity, pH, surface browning, sugar decomposition, and hydroxymethylfurfural (HMF) formation. Decreasing moisture to a level under a water activity of 0.4 appeared as the critical point in baking where the rate of HMF formation drastically increased after this point. After this stage, sucrose decomposed very rapidly if ammonium bicarbonate was used as the leavening agent at temperatures greater than 200 °C. Replacing ammonium bicarbonate with sodium bicarbonate maintained pH of cookies ranging between 9.0 and 10.0 during baking, which limited the decomposition of sucrose.  相似文献   

19.
Chlorination of wheat flour in the EU countries has been replaced in recent years, to some extent, by heat treated flour which is used to produce high ratio cakes. Heat treated flour allows high ratio recipes to be developed which generate products with longer shelf life, finer texture, moist crumb and sweeter taste. The mechanism by which heat treatment improves the flour is not fully understood, but it is known that during the heat treatment process, protein denaturation and partial gelatinisation of the starch granules occurs, as well as an increase in batter viscosity. Therefore, it is important to optimize the flour heat treatment process, in order to enhance baking quality. Laboratory preparation of heat treated base wheat flour (culinary, soft, low protein) was carried out in a fluidised bed drier using a range of temperatures and times. The gluten was extracted from the final product and its quality was tested, to obtain objective and comparative information on the extent of protein denaturation. The results indicated that heat treatment of flour decreases gluten extensibility and partial gelatinisation of the starch granules occurred. After heat treatment the gluten appeared to retain moisture. The optimum time/temperature for the heat treatment of base flour was 120–130 °C for 30 min with moisture content of ≈12.5%.  相似文献   

20.
以河北优质白麦为原料,研究了微波辐照功率、辐照时间、润麦水分、润麦时间等参数对全麦粉脂肪酶活动度、湿面筋含量的影响,考察了适度微波辐照对面粉粉质特性和糊化特性的影响。结果表明微波辐照能够显著降低(p<0.05)全麦粉的脂肪酶活动度和湿面筋含量。适度的微波辐照(微波功率420 W,辐照时间90 s,润麦水分14%,润麦时间25 min)能够大幅降低全麦粉脂肪酶活动度,同时对其湿面筋含量损伤较小,并提高面粉粉质稳定时间,降低弱化度,增加了面糊峰值粘度和回生值,改善了面筋强度和面糊稳定性,延缓了全麦粉脂肪酸值的升高。  相似文献   

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