Optimization of extrusion cooking of lung proteins by response surface methodology

Conditions for extrusion cooking of dried ethanol defatted bovine lung were optimized using response surface methodology (RSM) with the method of steepest ascent to maximize expansion ratio in terms of temperature of the central zone of the extruder and moisture content of the feed. Water absorption capacity showed no significant variation over the range studied, but the emulsifying capacity showed a significant increase with decreasing moisture content of the feed. The extruded product could improve utilization of an otherwise waste product.     

Investigation of the effects of extrusion cooking on antinutritional factors in soybeans employing response surface analysis Part 1. Effect of extrusion cooking on trypsin-inhibitor activity

A Brabender 20 DN laboratory scale extruder was used to study the effect of processing parameters on trypsin-inhibitor activity in dehulled soyabeans employing response surface analysis. Process variables examined were: Temperature of die (150, 160 and 170 °C), feed moisture content (12, 16 and 20%) and screw speed (80, 120 and 160 rpm). Trypsin-inhibitor activity of extruded products was measured. The correlation with a multiple determination coefficient, (R² = 0.976) and the mathematical model developed in this study were found to be significant.     

基于响应曲面法分析速煮绿豆加工工艺

实验对速煮绿豆加工工艺进行了优化,单因素实验表明浸泡时间、浸泡温度、蒸煮时间、蒸煮温度对复水性影响较大,且干燥方式对速煮绿豆的组织结构和形态保持上有明显影响;通过响应曲面回归分析,得到速煮绿豆优化加工工艺条件:在42℃0.5%NaHCO3浸泡液下浸泡4h,常压下100℃蒸煮40min,沥干,先恒温热风干燥30~40min,放置在密封容器24h,再微波干燥4~6min至水分含量为5%~7%,复水时间为5~12min。     

Extrusion cooking of barley flour and process parameter optimization by using response surface methodology

BACKGROUND: The nutritional profile of barley places it in a prime position for development of a new extruded–expanded snack food with health benefits. It was therefore the aim to investigate the effect of extrusion processing variables on system parameters (specific mechanical energy, die pressure and die melt temperature) and physical properties (expansion, bulk density, texture and color) of barley flour extrudates and to optimize processing conditions for production of extruded snack food from barley flour by response surface methodology. RESULTS: Barley flour with 219.7 g kg^?1 moisture content was extruded at different die temperatures (140–160 °C) and screw speeds (150–200 rpm) through a co‐rotating twin‐screw extruder. The system parameters as well as product responses were mainly dependent on temperature, whereas the screw speed imparted a lesser effect. Extrudates produced under extrusion conditions of 160 °C, 150 and 200 rpm and at 164 °C and 150 rpm had higher preference levels of appearance, taste, texture and overall acceptability than that of other selected extrudates for sensory analysis. The optimal conditions for minimum bulk density and desired textural characteristics and color of extrudates correspond to a temperature of 156 °C and screw speed of 166 rpm. CONCLUSION: The results suggested that use of barley flour in extruded snack products offers a desirable variation in diet and can take advantage of the nutritional quality of barley. Copyright © 2008 Society of Chemical Industry     

响应面法优化复合食品添加剂对猪肉蒸煮出品率的研究

为了提高猪肉的保水性,以猪肉蒸煮出品率为评价指标,首先将三聚磷酸钠、焦磷酸钠、六偏磷酸钠按4∶3∶2比例复配成复合磷酸盐添加到猪肉中,猪肉的蒸煮出品率为85.47%。在单因素工艺实验的基础上,应用响应面分析法对复合磷酸盐、谷氨酰胺转氨酶、大豆分离蛋白、卡拉胶添加量进行优化,结果表明,最佳添加量为复合磷酸盐0.36%、TG酶0.60%、卡拉胶0.20%、大豆分离蛋白0.41%,在此条件下,猪肉蒸煮出品率可达到89.5311%。验证实验猪肉蒸煮出品率为89.1%±0.4%,表明实验结果与软件优化结果相符。      

响应面法优化复合食品添加剂对猪肉蒸煮出品率工艺研究

为了提高猪肉的蒸煮出品率,首先将三聚磷酸钠∶焦磷酸钠∶六偏磷酸钠按4∶3∶2比例复配成复合磷酸盐添加剂。以猪肉蒸煮出品率为评价指标,在单因素工艺试验的基础上,应用响应面分析法对复合磷酸盐、谷氨酰胺转胺酶、大豆分离蛋白、卡拉胶添加量进行优化,结果表明,最佳添加量为复合磷酸盐0.36%、TG酶0.60%、卡拉胶0.20%、大豆分离蛋白0.41%,在此条件下,猪肉蒸煮出品率可达到89.5311%。验证试验猪肉蒸煮出品率为(89.1±0.4)%,表明实验结果与软件优化结果相符。     

Flow rate and heat transfer modelling in extrusion cooking of soy protein

This paper presents a model representing the heat transfer in extrusion cooking of defatted soy protein flour in a single-screw extruder. Depending on the importance of the Peclet and Brinkman numbers, both viscous heating and convective heating are involved. Temperature profiles are therefore considered as a function of transverse and longitudinal positions as well as of Peclet and Brinkman numbers.Using the temperature profiles, the flow rates are then determined for various screw speeds (30–133 rpm) and barrel temperatures (150°C–190°C) by applying the non-Newtonian analysis previously used in polymer processing. The predicted values are compared with experimental values.     

曲面响应法优化设计抗性淀粉膨化工艺的研究

在单因素实验的基础上,利用曲面响应法中心组合设计,对抗性淀粉膨化工艺进行了优化设计。选择原料的水分含量,模头温度以及螺杆转速为优化因素,研究了在不同水平上的因素对抗性淀粉含量的影响。通过响应面分析得到抗性淀粉膨化的最佳工艺参数:物料的水分含量7.5%、螺杆转速592r/min、模头温度150℃,在此条件下,膨化产品中抗性淀粉含量为17.945%±0.523%,与模型高度拟合。     

响应面法优化米糠调和油配比的研究

利用数学模型制备米糠调和油,在此基础上以诱导时间为响应值,采用响应面分析法优化米糠油、花生油和小麦胚芽油的配比,使调和后的油脂不饱和脂肪酸组成更合理且氧化稳定性更好。实验结果表明当米糠油、小麦胚芽油、花生油的质量分数分别为49.6970%、10.4545%、40.8485%时,诱导时间最大,为6.31620 h。与优化前相比提高了29.85%。     

Fat,wheat bran and salt effects on cooking properties of meat patties studied by response surface methodology

Response surface methodology was used to investigate the main effects and interactions of composition (processing) variables such as fat (10–30%), wheat bran (5–15%) and NaCl (0–2%) on cooking properties of beef patties. In addition, the ridge analysis was conducted to find the values of processing variables that maximise and minimise the cooking parameters (moisture retention, fat retention, reduction in thickness, reduction in diameter, cooking yield, shrinkage and water‐holding capacity). It was found that the moisture and fat retention, reduction in thickness and cooking yield values decreased; however, reduction in diameter and shrinkage values increased, respectively, as the amount of fat increased. However, wheat bran addition increased fat retention, moisture retention, cooking yield and water‐holding capacity values of the patties. Increasing NaCl levels decreased water‐holding capacity value by its quadratic effect and moisture and fat retention value by its interaction effect with wheat bran.     

Optimisation of fermentation conditions for mango (Mangifera indica L.) wine production by employing response surface methodology

Response surface methodology (RSM) was employed for the simultaneous analysis of fermentation conditions of temperature, pH and inoculum size on chemical characteristics such as ethanol, glycerol and volatile acidity, produced during mango wine production by Saccharomyces cerevisiae ( var. bayanus ). The experiments were carried out according to the central composite design to establish the optimum conditions for improving the quality of mango wine. The predicted values for optimisation process conditions were in good agreement with experimental data. The results showed that a satisfactory production of ethanol from the mango juice could be achieved reaching up to 10% (v/v), glycerol concentration is increased to 6.94 g L⁻¹ and volatile acidity is minimised to 0.29 g L⁻¹ at optimised fermentation conditions of temperature 22.5 °C, pH 3.8 and inoculum size 11.9%. Verification of the model indicated no difference between predicted and observed values. Sensory evaluation studies shown overall acceptance of mango wine with good quality.     

Formation of flavors during extrusion cooking

Abstract

Extrusion cooking is a high‐temperature/short‐time process which is ideal for the production of flavor volatiles. However, due to the nature of this process there are many opportunities for these volatiles to be lost. This has led many researchers to study the formation and retention of volatiles during extrusion. This review focuses on the flavor‐related reactions which may occur during extrusion, including their occurrence in various flours and due to the addition of reactive precursors.     

Response surface methodology in the control of thermoplastic extrusion of starch

Effect of extrusion temperature, screw speed and moisture content on the gelatinisation properties of extruded corn starch using a single-screw extruder were studied using response surface methodology. The degree of gelatinisation can be effectively controlled by controlling the moisture content of the raw material and the extrusion temperature; control by manipulation of screw speed is also possible when the raw material has a high moisture content. The extrudate produced from starch with a low moisture content exhibited a very low retrogradation capacity, which was independent of the screw speed. It was evident that variation of operating conditions permits the production of an extrudate with various technological characteristics to meet varying food and industrial applications, and the use of response surface analysis seems to be an effective means of studying and optimising these conditions for extrusion technology.     

Effect of extrusion on the emulsifying properties of soybean proteins and pectin mixtures modelled by response surface methodology

The objective of this study was to apply response surface methodology to estimate the emulsifying capacity and stability of mixtures containing isolated and textured soybean proteins combined with pectin and to evaluate if the extrusion process affects these interfacial properties. A simplex-centroid design was applied to the model emulsifying activity index (EAI), average droplet size (D_[4,3]) and creaming inhibition (CI%) of the mixtures. All models were significant and able to explain more than 86% of the variation. The high predictive capacity of the models was also confirmed. The mean values for EAI, D_[4,3] and CI% observed in all assays were 0.173 ± 0.015 nm, 19.2 ± 1.0 μm and 53.3 ± 2.6%, respectively. No synergism was observed between the three compounds. This result can be attributed to the low soybean protein solubility at pH 6.2 (<35%). Pectin was the most important variable for improving all responses. The emulsifying capacity of the mixture increased 41% after extrusion. Our results showed that pectin could substitute or improve the emulsifying properties of the soybean proteins and that the extrusion brings additional advantage to interfacial properties of this combination.     

Effects of temperature and protein content on physical properties of pasta made from rice enriched with soybean by extrusion cooking. Part I. Effect on water absorption and solubility employing response surface analysis

Rice flour was mixed with various amounts of defatted soybean flour in order to obtain a mixture with protein levels of 15, 20 and 25%. These mixtures were processed in a one-screw Brabender 20 DN extruder at temperatures of 80, 100 and 120 °C. Below 20% of protein concentration, the water absorption index (WAI) increased, with increasing extrusion temperature, and below 90 °C the WAI increased with increasing protein concentration. The water solubility index (WSI) notibly increased with increases in both temperature and protein concentration.     

Optimisation of a model food mixture using response surface methodology to evaluate the anti‐adhesive properties of cooking materials

The composition of a model food was optimised to evaluate the anti‐adhesive properties of cooking materials. This optimisation was performed using a response surface methodology. When cooked at 201 °C, the model food was selected to leave the greatest quantity of cooked residue that cannot be removed easily from the utensil surface. The measurement of the surface covered by the cooked food left after cleaning was the response value of the experimental design. The effect of five macronutrients was evaluated. Glucose and ovalbumin factors showed the most important positive effect, while amylopectin presented a negative effect. The optimum concentration values of the food constituents where highest food adsorption was estimated were 34.5 mg mL^?1 glucose, 14.5 mg mL^?1 amylopectin, 39.0 mg mL^?1 ovalbumin, 13.5 mg mL^?1 casein and 32.8 mg mL^?1 linoleic acid. The predicted results at the optimum point coincided well with experimental values. The optimum food mixture presented good precision as well.     

基于响应面法构建虾青素纳米乳液

为提高虾青素的稳定性,以生物大分子卵磷脂为乳化剂,采用高压均质法制备负载虾青素的纳米乳液,在单因素实验的基础上,以纳米乳液粒径和虾青素负载率为响应值,以乳化剂浓度、油水比、虾青素添加量3个因素为响应因子,利用响应面法建立二次回归方程模型,获得制备虾青素纳米乳液的最佳工艺条件为:乳化剂浓度1%(w/w),乳化温度55 ℃,乳化时间45 min,油水比1:8.5,虾青素添加质量分数为0.5%(w/w),按此工艺条件制备得到虾青素纳米乳液的粒径为238.84 nm,虾青素负载率可达到90.41%。     

响应面法优化木聚糖酶发酵培养基的研究

采用响应面法对毕赤酵母发酵产木聚糖酶的培养基进行了优化。首先利用Plackett Burman试验设计筛选出影响产酶的3个主要因素,即麸皮水解液浓度、酵母水解液浓度和甲醇添加量。在此基础上用最陡爬坡路径逼近最大响应区域,再利用Box-Behnken试验设计及响应面分析法确定最佳条件。结果表明,麸皮水解液402.5g/L、酵母水解液49.9 g/L和甲醇添加量为28.1mL/L时,木聚糖酶最大理论酶活为6566.79U/mL。经3次试验验证,实际平均酶活与预测酶活相近,比优化前木聚糖酶酶活提高了23.7%。