菜籽及菜籽仁出油压力与出油率的试验研究

利用可视化柱塞式压榨试验装置对菜籽和菜籽仁进行压榨试验,揭示了压榨取油的微观机制与过程,提出了出油压力、出油应变概念,并对其进行了试验。结果表明,菜籽的出油压力远大于菜籽仁的出油压力。试验探讨了菜籽和菜籽仁的出油率与出油压力的关系,并得到两者的对数关系。     

菜籽及菜籽仁出油压力与出油率的试验研究

利用可视化柱塞式压榨试验装置对菜籽和菜籽仁进行压榨试验，揭示了压榨取油的微观机制与过程，提出了出油压力、出油应变概念，并对其进行了试验。结果表明，菜籽的出油压力远大于菜籽仁的出油压力。试验探讨了菜籽和菜籽仁的出油率与出油压力的关系，并得到两者的对数关系。     

菜籽仁冷榨饼的膨化浸出研究与实践

介绍了菜籽仁冷榨饼膨化浸出的工艺、操作方法及生产应用情况。通过膨化处理破坏了菜籽仁冷榨饼的细胞组织结构,提高了物料的容重,显著改善了物料的浸出性能。膨化加工不仅解决了菜籽仁冷榨饼的浸出难题,还可提高菜籽粕和浸出毛油质量、扩大浸出器生产能力、降低浸出生产成本。     

100t/d低温螺旋榨油机的研制

在对压缩比、施压速度、压榨时间、压榨过程的保温、防磨措施、榨料性质调节等关键技术进行深入研究的基础上,研制成功了LYZX系列100 t/d低温螺旋预榨机。实测该机生产能力达83.5~92 t/d脱皮菜籽仁,在65℃温度下入榨,一次压榨干饼残油率小于17%;装机容量为99 kW。     

4种油料压榨饼的品质评价

对油菜籽、亚麻籽、紫苏籽、花生仁4种油料及在适宜条件下压榨所得压榨饼的粗蛋白质含量、氮溶指数、氨基酸组成及含量的变化进行评价。结果显示:亚麻籽饼、菜籽饼、花生饼和紫苏籽饼中粗蛋白质含量均比4种油料的粗蛋白质含量明显增加,其氮溶指数与油料相比也相应增加;4种压榨饼的赖氨酸含量均较油料明显上升。这说明压榨过程中,由于压榨温度低、受热时间短,随着油料所含油脂被压榨出来,压榨饼中蛋白质含量得以升高,饼中蛋白质尚未变性或稍有变性,这为压榨饼的蛋白质资源开发利用创造了有利条件。     

油菜籽脱皮、低温压榨、膨化浸出制油新工艺

报道了一种油菜籽脱皮、低温压榨、膨化浸出制油新工艺.油菜籽用YTPG100型油菜籽脱皮机脱皮,其脱皮率高达96%以上,仁皮分离后,含皮仅2%的菜籽仁再经过LYZX·24型低温螺旋榨油机在常温至65℃压榨制得低温压榨菜籽油.低温压榨菜籽油经沉淀和过滤后即得成品油,其质量接近菜籽油一级国家标准(GB 1536-1986).低温压榨饼经YPH·20型挤压膨化机组织化处理,形成多微孔颗粒膨化料,经溶剂浸出制得残油率1%左右、蛋白质含量46%以上(干基)的菜籽粕.     

大豆的液压冷榨工艺及压榨特性

为研究大豆压榨过程中压榨特性的变化,以大豆为原料,探究了压榨时间、填料高度和压榨次数对残油率、压缩比、孔隙度、渗透率、微观结构的影响。结果表明：随着压榨时间的延长,大豆饼残油率先快速降低后趋于平缓;随着填料高度的增加,大豆饼残油率增加,压缩比减小,孔隙度增加,渗透率增加;二次压榨后大豆饼残油率降低,压缩比增加,孔隙度降低,渗透率降低;微观结构分析表明,随着填料高度的增加,细胞破碎率降低,更多的油脂残留在细胞内。因此,在实际生产中要合理控制压榨时间、填料高度和压榨次数来提高压榨效率。     

紫苏籽、花生仁压榨特性的研究

为了开展油料产地化低残油压榨技术装备研究,以紫苏籽、花生仁为原料,研究2种油料的物性(包括原料成分及硬度和脆性)。采用小型榨油机(该机为榨螺和榨轴一体的单螺杆榨油机,测量并计算其理论压缩比为11)压榨,以压榨饼残油率为指标,考察油料入榨含水量,入榨温度,环境温度等因素对2种油料压榨饼残油率的影响。通过正交试验优化得到最佳压榨工艺条件为:入榨水分为4%,入榨温度为65℃,环境温度为30℃,在最佳工艺条件下,紫苏籽压榨饼残油率为9.82%;花生仁压榨饼残油率为8.21%。由于出饼温度小于80℃,随着紫苏籽压榨饼和花生仁压榨饼中蛋白质含量增加,其氮溶指数与原料相比也有所增加,说明蛋白质尚未变性。另外,利用透射电镜对2种油料种子子叶细胞及最佳工艺条件下的压榨饼进行微观结构观察。证实了油料种籽子叶细胞中油脂以脂类体形式储存在细胞的内质网状结构以及蛋白体和糊粉粒的间隙中,压榨时在外力挤压作用下油料细胞结构严重变形并被破坏,油被压榨出并同时实现与饼的液-固分离。     

压榨饼残油含量的快速测定方法

为满足工厂试验及大数据研究对压榨饼残油含量的即时化测定需求,建立了基于压榨毛油紫外光特征吸收的快速测定方法。以庚烷-乙醇混和溶剂萃取压榨饼,采集所得萃取液紫外吸收的D255值(255 nm处一阶导数放大100倍),再根据标准曲线计算压榨饼残油含量,可通用于菜籽直接压榨、低温压榨、脱皮压榨、高温压榨和预榨等多种工艺效果的评价。该方法同样适用于花生仁、紫苏籽、亚麻籽等多种油料压榨饼残油含量的测定,且变异系数不大于4.27%,测定回收率在95.12%～104.04%之间。     

菜籽脱皮冷榨的理论和实践

介绍了对菜籽脱皮和冷榨工艺的研究结果。结果显示,脱皮冷榨毛菜籽油的质量与脱胶油相同,类似于中和后的油,同时压榨饼在相同能量供给试验中,对家禽饲养较不脱皮菜籽饼表现出一更高的增重率。由于脱皮冷榨菜籽油不需精炼即可食用,因此,该工艺也许可叫做绿色油脂加工工艺,它不仅避免了对食用油的热和化学处理,同时提高了压榨饼对家禽的增重率。     

油菜籽及其脱皮冷榨应力应变关系的神经网络模型

进行了单面渗流下油菜籽及其脱皮冷榨的应力、应变试验,研究了不同加载速率对应力、应变关系和出油量的影响,建立了基于BP神经网络的应力、应变关系模拟模型,对油菜籽及其脱皮单面渗流一维冷态压榨下的应力、应变关系进行了模拟.结果表明,在相同压榨应力下,加载速率对其应变关系和出油量的影响均较大,应变和出油量均随加载速率的减小而增加;脱皮油菜籽的应变大于未脱皮油菜籽的应变.BP神经网络模拟油菜籽的应力、应变是一种有效的方法.     

侧限双面渗流压榨下的菜籽应力应变关系研究

进行了双面渗流下菜籽及其脱皮冷榨的应力、应变试验。结果表明:在相同压榨应力下,单面渗流下的应变、小于双面渗流下的应变;加载速率对其应力、应变关系的影响均较大,应变随加载速率的减小而增加;脱皮菜籽的应变大于未脱皮菜籽的应变;川北方程能较好模拟菜籽及其脱皮的侧限单面排油压榨的应力、应变关系。     

利用菜籽饼粕生产复合氨基酸的研究

众多的研究表明,菜籽蛋白对人具有很高的营养价值,其氨基酸组成和ＷＨＯ／ＴＡＯ推荐的比例很接近。文介绍了以菜籽饼粕为原料,用酶－酸两步水解法生产复合氨基酸的方法,对原料的选择处理、酶解以及酸解条件、沉淀剂的使用等方面进行了研究和探讨,建立了生产氨基酸的工艺路线,并且生产的复合氨基酸的纯度、产品得率、氨基酸组成、安全性能等进行了初步评价。     

Influence of rapeseed cake, linseed cake and hemp seed cake on laying performance of hens and fatty acid composition of egg yolk

In hens the effects of expeller/cakes from rapeseed, linseed, and hemp seed were investigated on feed intake, laying performance and fatty acid composition of egg yolk. A total of 216 individually caged laying hens were allocated to nine dietary treatments (5, 10, 15 % cake) and fed for six laying months. For feed intake, egg mass production and feed-to-egg mass ratio at 15 % dietary cake level a significant lower performance was shown compared with the 5 and 10 % cake level groups. Also interaction was significant for all these parameters, indicating that the cake level acted differently for the three cakes. The egg mass production was lower in the linseed cake than in the hempseed groups and the hens fed the linseed cake needed significantly more feed per kg egg mass compared with both the other cakes tested. Increasing dietary level of all oil seed cakes lowered the yolk percentage and increased the egg white percentage. Increased dietary levels of all three oil seed cakes lowered the percentages of most saturated fatty acids and also the percentages of the monounsaturated fatty acids. The linoleic acid and the linolenic acid as polyunsaturated fatty acids were heightened by increasing the cake levels from 5 to 10 and 15 % in the diet. The results allow the conclusion that compound feeds with up to 10 % of cakes does not negatively influence the laying performance of hens and provides the possibility of the enrichment of yolk fat with polyunsaturated fatty acids.     

Measurement and Modelling of Thermal Conductivity of Sponge and Yellow Cakes as a Function of Porosity

A review of the literature identified that there is significant scatter in the data for the thermal conductivity of cakes (including muffins). Most data have been obtained using the line source or thermal conductivity probe method. In this work the thermal conductivity of two types of cakes (sponge cake and yellow cake) were measured over a range of porosities, using a transient comparative method. The thermal conductivity data measured in this work were generally lower than the data measured by the probe or line source method; however, they appeared to lie on a similar curve to the data collated by previous workers who measured thermal conductivity at porosities outside the range considered in this work. The thermal conductivity of the cakes was modelled assuming the cakes were binary materials made up of a condensed phase and air, using equations that did not contain any empirical parameters. Of the eight thermal conductivity models considered, the effective medium theory model provided the most accurate predictions for thermal conductivity as a function of porosity.     

Rheological,Physical, and Sensory Attributes of Gluten‐Free Rice Cakes Containing Resistant Starch

In this study the effect of resistant starch (RS) addition on gluten‐free cakes from rice flour and tapioca starch physical and sensorial properties was investigated. Increase in RS concentration made cake batters less elastic (drop of G'(ω), G''(ω) values) and thinner (viscosity decreased). Cakes specific volume increased with an increase in RS level and was maximized for 15 g/100 g RS, although porosity values were significantly unaffected by RS content. Crumb grain analysis exhibited a decrease in surface porosity, number of pores and an increase in average pore diameter as RS concentration increased. During storage, cake crumb remained softer in formulations with increasing amounts of RS. Sensory evaluation of cakes demonstrated the acceptance of all formulations, with cake containing 20 g/100 g RS mostly preferred. Gluten‐free cakes with improved quality characteristics and high nutritional value can be manufactured by the incorporation of RS.     

低温冷榨过程中油菜籽出油率影响因素仿真分析

目的:探究油菜籽在双螺旋榨油机中压榨时出油率的影响因素。方法:对油菜籽的压榨过程进行仿真,并探索榨螺转速和孔隙度两个因素对出油率的影响。结果:油菜籽出油率与孔隙度呈线性关系,孔隙度越大出油率越低;出油率与榨螺转速呈负相关。结论:当孔隙度为0.45,榨螺转速为20 r/min时,油菜籽出油率最高。     

Effect of batter freezing conditions and resting time on cake quality

The aim of the present study was to investigate the effects of batter freezing and conditions and resting time before baking on quality of two kinds of cakes (layer and sponge cakes), including freezing temperature (−18 °C, −26 °C), storage time at sub-zero temperatures (30 and 100 days), and resting time (60 and 120 min). Characteristics of the batter (pH, density, viscosity, and microstructure) and cakes (density, texture, and colour) were analysed. Freezing process increases batter density and viscosity, and consequently decreases cake volume and height, but increases hardness. Cakes from frozen batters have a darker and more yellow crumb and lighter-coloured crust than cakes from non-frozen batters. Freezing process has a greater effect on batter and cake quality characteristics than storage/freezing conditions or resting time. In layer cakes, freezing mainly affected volume and colour, whilst in sponge cakes, there was a more marked effect on texture. Differences between the two kinds of cake could be related to a distinct internal structure. Resting time mainly affected batter characteristics, although there were no apparent differences in the quality of the cakes obtained.     

EFFECT OF ADDITION OF LOW SUGAR RAISINS (LSR) ON PHYSICAL PROPERTIES OF CAKES DURING STORAGE

The influence of low sugar raisins (LSR) on the physical properties of cakes containing different quantities of raisins (0–25%) during a short storage of 7 days was investigated. Porosity, crumb density, moisture content, sorption isotherms of raisins, weight loss and mechanical properties (compression and relaxation experiments) were determined for cakes during storage. During the first 3 days of storage slight changes are observed in the physical properties of all cakes. Thereafter, density and weight loss increase, the porosity decreases and samples become firmer. Control cakes are less firm but also more elastic, and the solid‐like materials show the greatest porosity reduction and shrinkage during storage. Raisins in cakes absorb water at the beginning of storage. As the quantity of raisins increases, their moisture content during storage changes less. Cakes containing 25% raisins have the lowest weight loss during storage. Although their firmness increases during storage, their viscoelastic properties remain constant.