高蛋白含量棉粕的生产工艺探讨

结合我公司在棉籽加工枝术中采取的各项改进措施,对棉籽加工过程中影响棉粕蛋白质含量的各关键控制点进行控制。主要包括在仁壳分离工艺中采用多道循环筛分工艺,将阶梯筛和平面回转筛进行优化组合;在棉仁压坯过程中通入蒸汽,提高坯片的软化效果;对浸出器增加预浸和料翅改造,有利于棉粕中棉酚的脱除;湿粕经离心机分离、圆盘烘干机低温烘干、蒸脱机脱溶,可缩短湿粕的烘干时间,降低烘干温度,减少蛋白质变性。通过各关键控制点的控制,棉粕产品中残油一般在0.5%以下,粗蛋白质含量可达60%~62%,氢氧化钾溶解度达70%~75%,游离棉酚含量不高于200 mg/kg,大大改善了棉粕的品质。     

利用有腺体棉籽粕生产食用棉仁分离蛋白的实践

棉仁蛋白是一种潜在的重要食品资源,由于棉酚的存在一直未被人类充分利用。通过甲醇脱酚、4#溶剂脱脂、低温连续脱溶的棉籽粕生产工艺和碱溶酸沉的蛋白生产工艺,于2001年首次实现了工业化利用有腺体棉籽粕生产食用棉仁分离蛋白的实践,获得了高安全性的棉仁分离蛋白。     

棉仁膨化生产棉仁蛋白及喂猪试验

阐述了棉籽膨化法生产了棉仁蛋白的工艺和生产技术，比较了不同工艺生产的棉粕的质量，通用用膨化棉仁粕替代和部分替代豆粕的喂猪试验，表明膨化棉仁粕与豆粕饲喂效果无显著差异。     

从双液相棉粕中萃取蛋白过程动力学分析

为有效萃取棉籽蛋白提供理论依据，推导出了从双液相棉粕中萃取蛋白质过程的宏观动力学方程，概括了温度、棉粕粒径、萃取时间、碱液浓度等对萃取蛋白质动力学的影响，方程与实验结果吻合较好，萃取过程的表观活化能Eα为7、3kJ／mol，属于内扩散控制。     

低温脱酚棉籽蛋白与普通棉粕和高蛋白棉粕的比较

介绍了低温脱酚棉籽蛋白与普通棉粕、高蛋白棉粕的本质差异,解决了长期以来一直困扰着棉籽加工业、饲料业、养殖业的如何生产和应用低温脱酚棉籽蛋白产品,使企业经济效益、社会效益进一步提升的问题。     

棉籽粕脱酚方法的研究

采用热水,热碱,硫酸亚铁,米曲霉四种方法,对棉籽粕进行脱酚实验,结果热 法去酚效果最佳。通过正交试验,热碱法脱酚的最适条件为ｐＨ８－９,温度６０℃,时间３ｈ,最终棉籽蛋白液棉酚含量为１２ｐｐｍ,完全低于联合国咨询委员会规定的食用棉籽蛋白质中游离棉酚含量≤０．０６％标准。     

高蛋白脱酚棉籽粕制取工艺研究

为了满足市场需求,提升棉籽粕利用价值,结合实际生产情况,采用单因素控制变量法,调整生产工艺中关键控制参数如原料棉仁中的含壳率、甲醇溶液萃取工艺参数以及成品粉碎筛分条件等,确定了分别以含壳率为2%和5%的棉仁为原料的高蛋白脱酚棉籽粕生产工艺。当原料含壳率为2%时,适宜的萃取工艺为浸泡萃取,料液比1∶3,浸泡萃取脱酚时间30 min,甲醇溶液萃取梯度60%-70%-80%-90%,共萃取4次,残油控制在0.7%以下,蒸脱烘干控制水分在5%以下。原料含壳率为5%时,适宜的萃取工艺为淋液萃取,料液比1∶2,甲醇溶液萃取梯度70%-70%-70%-70%-80%-90%,共萃取6次,残油控制在0.7%以下,蒸脱烘干控制水分在5%以下。采用上述两种方法,可得到粗蛋白质含量在70%以上、游离棉酚含量满足企业内控指标要求(≤400mg/kg)的脱酚棉籽粕。     

高蛋白棉粕的制取工艺设计及实践

阐述了以棉籽为原料,在预榨浸出、一次浸出、膨化浸出、低温脱酚萃取不同生产工艺处理下的关键指标,如游离棉酚含量、能耗、棉粕色泽等。经研究分析,选择膨化浸出生产工艺制取高蛋白棉粕,经过清理、剥壳、仁壳分离、软化、轧胚、调质、膨化、冷却、浸出、蒸脱、研磨、筛分,最后得到蛋白含量高达50%~53%的棉粕。     

浅谈低变性棉籽粕的制备

生产棉籽蛋白的原料棉籽粕在预处理、浸出、脱溶工段与普通的工艺相比有着特殊的要求,从而保证制得的棉籽粕在含杂、蛋白质变性程度、色泽、纤维素含量等方面符合要求。通过生产试验研究了低变性棉籽粕的制备工艺。     

棉籽仁壳分离系统改造实践

棉籽中蛋白质含量丰富,为生产高蛋白质含量棉籽蛋白,对棉籽仁壳分离系统进行改造。通过设计,调整剥壳、筛分、风选系统,对棉籽仁壳分离系统工艺及设备进行优化,得到含壳3%~5%的棉仁过程产品,通过浸出(脱脂脱酚)可得到蛋白质含量为60%~62%的棉籽蛋白产品。该蛋白产品可用于鱼饲料,从而提高棉籽的附加值,促进棉籽加工业的发展。     

棉籽仁壳分离系统改造实践

传统的棉籽仁壳分离系统存在仁壳分离效果不佳,进而影响棉籽蛋白产品中蛋白质含量的问题,为此对传统棉籽仁壳分离系统进行了改造。通过对剥壳前光棉籽进行调质处理,优化仁壳分离工艺,可将棉仁含壳率由10%～15%降至2%～4%,棉壳含仁率由0.5%～0.8%降至0.1%～0.3%,通过浸出(脱脂脱酚)后可得到蛋白质含量为60%～65%的棉籽蛋白产品。     

The effects of varying gossypol intake from whole cottonseed and cottonseed meal on lactation and blood parameters in lactating dairy cows

Effects of varying amounts of gossypol from whole Upland cottonseed (WCS) and cottonseed meal (CSM) were evaluated in 40 midlactation Holstein cows. After 14 d of pretreatment, cows were assigned to 1 of the 5 treatments for 84 d: control (no gossypol), 931 mg/kg total gossypol (TG) and 850 mg/kg free gossypol (FG) from WCS (moderate TG and high FG); 924 mg/kg TG and 91 mg/kg FG from CSM (moderate TG and low FG), 945 mg/kg TG and 479 mg/kg FG with equal amounts of TG from WCS and CSM (moderate TG and FG), or 1894 mg/kg TG and 960 mg/kg FG with equal amounts of TG from WCS and CSM (high TG and FG). Concentrations of plasma gossypol (PG) and its isomers were directly proportional to FG intake. Concentrations of PG reached a plateau after 28 d on treatment, and they were highest in cows receiving a diet with high TG and FG. Erythrocyte fragility differed among treatments and increased with increasing FG intake. Plasma gossypol returned to negligible concentrations 28 d after withdrawal of cottonseed products from the high TG and FG diet. Serum vitamin A was similar among treatments, but vitamin E increased with increasing FG intake. Serum enzymes were generally unaffected by treatments, but urea N increased in diets higher in TG and FG. Intake of dry matter was higher for the diet high in TG and FG than for the control diet, but was similar for other treatments. Cows receiving the high TG and FG diet produced more milk and 3.5% fat-corrected milk, with no changes in milk composition. Feeding a diet containing 1894 mg/kg TG and 960 mg/kg FG for 84 d increased PG concentrations and erythrocyte fragility and resulted in minor changes in blood metabolites and enzymes, but no detrimental effect on lactation performance was observed. Indicators of liver, kidney, and muscle cell viability suggest that the higher amounts of gossypol consumed in this study had only minor effects on those tissues in lactating dairy cows.     

Effects of source of gossypol and supplemental iron on plasma gossypol in Holstein steers

Four experiments were conducted to evaluate factors influencing concentrations of plasma total gossypol (TG) in 30 Holstein steers fed cottonseed products. At the end of each 28-d experiment, steers were weighed and blood samples were collected and analyzed for plasma TG concentrations. During the entire study, steers did not show any overt signs of gossypol toxicity. In the 28 d before experiment 1, 30 steers with a body weight (BW) of 273 kg were fed a standardization diet with 15.0% Upland whole cottonseed (WCS) that resulted in a mean intake of 9.08 g/d of TG per steer/d and a plasma TG of 1.66 μg/mL. In experiment 1, 30 steers were fed 1 of 5 diets with 15.0% Upland WCS, but different levels of supplemental Fe [0, 150, 300, 450, and 600 mg/kg of diet dry matter (DM)]. Average daily gain was not affected by level of Fe in the diet, but DM intake, plasma TG, and plasma TG response decreased linearly as Fe in diets increased. In experiment 2, steers were fed diets with 15.0% Upland cottonseed as whole, cracked, roasted, cracked-roasted, or extruded. Analysis of the seed revealed that roasting or extrusion markedly reduced free gossypol (FG) content. Minor effects on animal performance were observed, but plasma TG decreased with roasting or extrusion of seeds, with the greatest reduction when the seed was cracked and then roasted. In experiment 3, steers were fed 2 levels of WCS (7.0 or 14.0% of DM) with 3 levels of cottonseed meal (2.8, 5.5, or 8.5% of DM) in the diet. Animal performance was not altered by diet, but plasma gossypol concentrations and responses were greater in steers fed diets with more WCS, because of the greater FG intake. In experiment 4, 24 steers were fed diets with 15.0% cottonseed (Upland or Pima) either as whole or cracked. Pima cottonseed increased TG and FG intakes, which resulted in greater plasma TG concentration and response. Animal response to processing of cottonseed tended to differ according to type of cottonseed. However, feeding Pima and cracking of cottonseed increased gossypol availability and plasma TG concentrations.     

棉籽加工中棉粕蛋白质含量和棉籽油色泽的控制

主要叙述了以棉籽为原料,生产加工后得到两个主要产品——棉粕和棉籽油,分别分析了影响棉粕蛋白质含量和棉籽油色泽的因素,并提出了控制各因素的关键点。在实际生产中,通过控制这些关键因素,可得到高蛋白的棉粕和高品质的棉籽油。     

棉籽加工预处理新工艺

采用剥壳机、圆打筛、仁壳分离筛、风筛比重组合分离机等设备,组成了一种新型的棉籽加工预处理新工艺.棉籽经过剥壳、分离处理后,壳中含仁率小于1%,仁中含壳率在1%左右;棉仁经过轧坯浸出后,可以降低粕中残油率,提高浸出生产能力10%,棉仁粕的蛋白质含量可以达到60%以上,大大提高了棉仁粕的利用价值.     

Short communication: Canola meal as a substitute for cottonseed meal in diet of midlactation Holsteins

The growing demand by humans for monounsaturated vegetable oils has provided canola meal (CM) for use in dairy diets because it possesses an excellent nitrogen profile for rumen microbes. Six midlactation cows were used in a replicated 3 × 3 Latin square design with 3 periods of 20 d each. Treatments included diets with 1) CM, 2) 50% CM + 50% cottonseed meal (CSM), and 3) CSM. Total crude protein (CP), nonprotein nitrogen, and rapidly degradable true protein (% of CP) were greater in CM than in CSM. The neutral and acid detergent fibers, slowly degradable true protein, and unavailable CP were lower in CM than in CSM. Daily feeding of 3.4 kg of CM instead of 5.6 kg of CSM enhanced milk percentage of protein and SNF, and improved total tract digestibility of dry matter and CP. Therefore, CM offers an economical substitute for CSM in midlactation diets when commercial access, cost, and quality of CSM are variable.