Effect of Steam Baking on Acrylamide Formation and Browning Kinetics of Cookies

Abstract: Effects of baking method and temperature on surface browning and acrylamide concentration of cookies were investigated. Cookies were baked in natural and forced convection and steam‐assisted hybrid ovens at 165, 180, and 195 °C and at different times. For all oven types, the acrlyamide concentration and surface color of cookies increased with increasing baking temperature. Significant correlation was observed between acrylamide formation and browning index, BI, which was calculated from Hunter L, a, and b color values, and it showed that the BI may be considered as a reliable indicator of acrylamide concentration in cookies. Acrylamide formation and browning index in cookies were considered as the first‐order reaction kinetics and the reaction rate constants, k, were in the range of 0.023 to 0.077 (min^?1) and 0.019 to 0.063 (min^?1), respectively. The effect of baking temperature on surface color and acrylamide concentration followed the Arrhenius type of equation, with activation energies for acrylamide concentration as 6.87 to 27.84 kJ/mol; for BI value as 19.54 to 35.36 kJ/mol, for all oven types. Steam‐assisted baking resulted in lower acrylamide concentration at 165 °C baking temperature and lower surface color for all temperatures. Steam‐assisted baking is recommended as a healthy way of cooking providing the reduction of harmful compounds such as acrylamide for bakery goods, at a minimal level, while keeping the physical quality. Practical Application: The kinetics of acrylamide formation and browning of cookies will possibly allow definition of optimum baking temperatures and times at convectional and steam‐assisted baking ovens. The kinetic model can be used by developing baking programs that can automatically control especially a new home‐scale steam‐assisted hybrid oven producing healthy products, for the use of domestic consumers.     

黑枸杞花青素抑制曲奇饼干中丙烯酰胺效果的研究

研究黑枸杞花青素对食品体系中丙烯酰胺的抑制效果。采用响应面分析优化焙烤温度、焙烤时间以及花青素在曲奇饼干中的添加量,获得抑制丙烯酰胺产生的最佳条件。结果显示,花青素可以有效抑制曲奇饼干中丙烯酰胺的产生;当焙烤温度为185℃,焙烤时间为12 min,花青素添加量为0.32 g/kg时,在此条件下丙烯酰胺抑制率为69.34%。研究表明:温度、时间、花青素添加量均对丙烯酰胺的产生具有显著影响,建立的二阶多项式模型准确性高,可以有效预测产品中丙烯酰胺的抑制效果。     

HPLC法测定曲奇饼干中丙烯酰胺的含量

确定了曲奇饼干中丙烯酰胺含量的高效液相检测方法.样品预处理采用脱脂,固液提取,离心破乳,液液萃取,旋蒸浓缩及氮气吹干,超纯水定容等步骤,经Kromasil ODS色谱柱(250 mm×4.6 mm,5 μm)分离.HPLC检测用甲醇-水(5:95,体积比)为流动相洗脱,VWD检测器检测波长210 nm.方法在0.2/mL～1.0μg/mL浓度范围内具有良好的线性关系(r=0.9998),检出限为4.4ng/mL,RSD为0.37％;定量限14.5 ng/mL,RSD为7.4％,加标回收率在81.6％～101.3％之间.本方法定量准确,操作简单,适用于曲奇饼干中丙烯酰胺的测定.     

Sensory and Nutritional Properties of Cookies Based on Wheat-Rice-Soybean Flours Baked in a Microwave Oven

Three formulas of cookies prepared from 50:45:5 (I), 50:40:10 (II) and 50:35:15% (III) wheat flour, broken rice flour, and defatted soy flour, respectively, baked in a microwave oven (2450 MHz) for 240 sec, were rated as the best of six formulas for flavor and texture by a trained panel. Cookies of formulas I and II were preferred over formula III by a consumer-type panel. Cookies of all three formulas showed no significant differences in nitrogen balance, apparent biological protein value and apparent net protein utilization. Apparent protein digestibility and protein efficiency ratio were significantly higher in formulas II and III than in formula I.     

Effect of Some Insoluble Milk Proteins on Sensory Characteristics of Appearance and Texture in Cookies

Lactalbumin, lactic casein, rennet casein, low-calcium and high-calcium co-precipitates were processed from skim milk and dried using both spray and pneumatic-conveying ring driers. Ring dried material was further divided into 30, 60 and 100 mesh sizes. All 20 protein products were tested in‘high’and‘low’protein cookies and evaluated by a trained sensory panel, using magnitude estimation scaling, for characteristics of appearance and texture. Processing effects, such as drying method and mesh size, had more effect on the cookies than protein type. These effects were greater in‘high’protein cookies than in‘low’protein cookies and were used to advantage in formulating‘high’protein cookies with a crisp and open texture.     

Study on Mitigation of Acrylamide Formation in Cookies by 5 Antioxidants

Abstract: This study investigated the capacity of various antioxidants in reducing the formation of acrylamide during cookie processing. Five antioxidants, antioxidants of bamboo leaves (AOB), sodium erythorbate (SE), tea polyphenols (TP), vitamin E (VE), and tert‐butyl hydroquinone (TBHQ), were individually added into cookie formulas, and acrylamide content was determined by liquid chromatography tandem mass spectrometry (LC‐MS/MS). Cookie quality indexes, including flavor, brittleness, and water activity, were also evaluated. Results showed that the maximum inhibitory rate of acrylamide by AOB was achieved with addition of 0.2 g/kg AOB. Addition of AOB (0.2 g/kg), TP (0.1 g/kg), VE (0.1 g/kg), SE (0.1 g/kg), and TBHQ (0.2 g/kg) mitigated the formation of acrylamide by 63.9%, 43.0%, 71.2%, 49.6%, and 54.1%, respectively. Sensory evaluation showed that the color, texture, and flavor of cookies processed with either AOB (0.2 g/kg) or VE (0.1 g/kg) had no significant difference compared to control cookies (P > 0.05). The present study indicated that AOB (0.2 g/kg) and VE (0.1 g/kg) could not only effectively mitigate the formation of acrylamide, but also retain acceptable sensory attributes of cookies. This work shows the potential effectiveness of antioxidants in food processing to decrease acrylamide formation. Practical Application: There is an urgent need for reducing the level of acrylamide produced during food processing. This study found that certain antioxidants (antioxidant of bamboo leaves and vitamin E) could effectively inhibit acrylamide formation in cookie processing without affecting sensory properties. The results suggested that the application of antioxidants could be an effective method to decrease acrylamide formation.     

Effects of Calcium Addition on Stability and Sensory Properties of Soy Beverage

Pasteurized or thermally processed soy beverages (6% soy solids) were fortified to a comparable level of cow's milk with 25 mM (or 30 mM) calcium using mixtures of calcium citrate and tricalcium phosphate. These fortified pasteurized products had acceptable sensory properties. Addition of these calcium salts did not adversely affect protein stability of the beverage. Calcium citrate addition caused a decrease in beverage pH and viscosity. Thermally processed (still retort and agitort) canned beverages containing calcium salts were stable for 6 months when stored at 1°C or at room temperature.     

原料特性对曲奇饼干品质和丙烯酰胺生成的影响

以面粉、油、糖为主要原料制作曲奇饼干,通过测量其水分含量、色度、质地、感官和丙烯酰胺含量,研究原料特性对曲奇饼干品质和丙烯酰胺生成的影响。实验表明:面粉中蛋白质的含量显著影响曲奇饼干的品质和丙烯酰胺的生成。与高筋粉和中筋粉相比,低筋粉粗蛋白含量仅为7.67%,其制作的曲奇饼干水分含量低,硬度小,柔软和酥松程度表现更好,品质最佳且丙烯酰胺生成量最低。普通黄油和发酵黄油制作的曲奇饼干酥脆,香味浓郁,品质优良,发酵黄油在焙烤过程脂肪氧化较为缓慢,生成的丙烯酰胺含量低为212μg/kg。红糖制作的曲奇饼干呈棕褐色,具有独特的香味,但丙烯酰胺含量高达828μg/kg。白砂糖、冰糖和绵白糖制作的曲奇饼干品质差异较小,其中白砂糖制作的曲奇饼干感官评价得分最高,丙烯酰胺含量最低为230μg/kg。综上,低筋面粉、发酵黄油和白砂糖制作的曲奇饼干品质较优,丙烯酰胺生成量较少。     

Effect of Radio Frequency Postdrying of Partially Baked Cookies on Acrylamide Content,Texture, and Color of the Final Product

Abstract: Effect of radio frequency (RF) postdrying of partially baked cookies on acrylamide content, texture, and color of the final product was investigated in this study. Control cookies were prepared by baking in a conventional oven at 205 °C for 11 min. Cookies partially baked for 8 and 9 min were postdried in a 27.12 MHz RF tunnel oven until attainment of the moisture content of control cookies. Internal temperature of cookies was monitored during the experiments to better explain the results. Cookies were analyzed for acrylamide content using a liquid chromatography‐mass spectrometry (LC‐MS) method. Texture measurements were performed using a Texture Analyzer, while digital image analysis was used for color measurement. The results showed that RF postdrying of partially baked cookies resulted in lower acrylamide levels (107.3 ng/g for control cookies, 74.6 ng/g upon RF postdrying of cookies partially baked for 9 min, 51.1 ng/g upon RF postdrying of cookies partially baked for 8 min). Instrumental texture analysis showed no significant difference among the texture of cookies, whereas RF postdried samples had a lower degree of browning. According to sensory evaluation results, control had a more crumbly texture, and RF postdried sample that was conventionally baked for 8 min had a slightly uncooked flavor. Practical Application: Combining radio frequency and conventional baking may provide cookie manufacturers with ability to make cookies with lower levels of acrylamide.     

Textural,Color, Hygroscopic,Lipid Oxidation,and Sensory Properties of Cookies Containing Free and Microencapsulated Chia Oil

Encapsulation of chia oil might protect omega-3 and omega-6 from lipid oxidation when producing baked foods. However, the actual gain in stability given by chia oil must be determined. In this work, chia oil or chia oil-loaded microparticles were added to a cookie formulation in order to evaluate the ability of the microcapsules in protecting chia oil from deterioration. Texture, color, water sorption isotherms, and sensorial properties were also evaluated. A hot homogenization technique was used with carnauba wax as an encapsulant, and the freeze-dried microparticles were incorporated into the cookie dough. Principal component analyses were carried out to evaluate lipid oxidation using the medium infrared spectra of the lipid fraction extracted from the baked cookies. It was found that the microencapsulated chia oil was better protected from oxidative deterioration during baking compared to the sample containing non-encapsulated chia oil. Textural analysis showed that chia oil (free and microencapsulated) acted as a coating on the wheat flour particles. Control cookies (no chia oil loaded) presented a more hydrophilic character. In the case of oil-loaded samples (free and microencapsulated), the isosteric heat of sorption behavior indicated an initial swelling step of the food polymers, resulting in the exposure of sorption sites of higher binding energies not previously available, and that this is because of the wheat particles being covered by the chia oil and the solid lipid microparticles. Furthermore, food acceptability did not change when the oil-loaded microparticles were added to the cookie formulation.     

Binding, Sensory and Storage Properties of Algin/Calcium Structured Beef Steaks

Structured beef steaks formed with the algin/calcium binder and with or without glucono-delta-lactone were compared with 100% beef controls and with structured steaks formed with salt and phosphate. Algin/calcium-treated products exhibited better binding and color in the raw state, but had lower palatability scores in the cooked state than salt/phosphate controls. Shelf-life of both algin/calcium products under aerobic conditions was similar to the all-beef control. In vacuum packages, however, the algin/calcium products showed more rapid gas production and microbial growth than all-beef and salt/phosphate controls. The algin/calcium treatment will allow increased marketing alternatives for meat products.     

改良油条中丙烯酰胺含量及其感官品质

为降低油条中丙烯酰胺含量,在油条制备过程中,分别采用全豆豆浆和胡萝卜浆及二者混合液代替纯水进行和面,优化工艺条件为:酵母粉用量1.4%(以面粉质量计)、温水pH 6.0、油炸温度190℃、油炸时间2.0 min,在此条件下,制备出对照组和试验组样品,测定其中丙烯酰胺含量并进行感官品质评价。结果表明,以面粉质量计,大豆和胡萝卜的单独添加量分别为28.3%和33.3%时,相应地,丙烯酰胺含量的降低率最高,分别为46.4%和39.0%,同时添加二者(14.2%大豆、16.7%胡萝卜)时,丙烯酰胺含量的降低率为54.6%;改良后的油条感官性状良好,总得分高于普通油条。     

紫甘薯全粉对面团流变特性与曲奇饼干品质的影响

为研究紫甘薯全粉添加量对面团流变学特性及曲奇饼干品质的影响,利用替代法将0%、10%、20%、30%、40%的紫甘薯全粉添加到曲奇饼干低筋面粉中。对不同比例混合粉面团流变特性进行分析,同时测定紫甘薯曲奇饼干色泽和质构,结合感官评价分析不同比例混合粉曲奇饼干的品质。结果表明:添加紫甘薯全粉后,面团吸水率和蛋白质弱化度显著升高,面团稳定时间、峰值扭矩、黏度指数、淀粉糊化速率显著降低。当紫甘薯添加量为30%,蛋白质弱化度最大为0.832 N·m,面团蛋白结构被破坏。随着紫甘薯全粉添加量的不断增加,G′、G"不断升高,tanδ逐渐降低,面团弹性占主导地位。随着紫甘薯全粉添加量的不断增加,紫薯曲奇饼干的色度L*值显著降低,a*值和b*值显著变化后在添加比例达到30%时趋于稳定,且这时的紫甘薯曲奇饼干色泽呈深紫、口感酥脆,咀嚼性较好,感官评分最高。紫甘薯全粉添加量在30%时曲奇饼干品质较好。     

氯化钙、木瓜蛋白酶对风干肉感官品质的影响

通过测定在不同浓度氯化钙和不同浓度木瓜蛋白酶、嫩化温度、嫩化时间处理下牛肉嫩度和风干肉感官品质的变化,研究氯化钙、木瓜蛋白酶对风干肉感官品质的影响。结果表明:氯化钙在4℃下嫩化4 h的最佳浓度为0.3 mol/L;木瓜蛋白酶嫩化的最佳浓度0.04%、嫩化温度55℃、嫩化时间2 h,木瓜蛋白酶浓度对牛肉嫩度的影响显著(p<0.05),其次是嫩化温度,嫩化时间对其影响不显著(p>0.05)。添加氯化钙和木瓜蛋白酶嫩化牛肉均能改善风干肉的感官品质。     

Storage Water Activity Effect on Oxidation and Sensory Properties of High-Oleic Peanuts

Peanuts were stored under different water activities and maintained using saturated salt solutions, for 14 wks. Peroxide values, percent moisture, and sensory attributes were determined at 2 wk intervals. Peroxide values increased over time for all treatments. The highest oxidation values were observed in the peanuts held under 0.67 water activity, followed by 0.12, 0.52, 0.44 and 0.33, respectively. Moisture increased over time for all samples and correlated with the water activity of storage. Roast peanut flavor decreased with time and the decrease was greater at higher a_w of storage.