Study on FTIR Spectra of Corn Germs and Endosperms of Three Different Colors Combining with Cluster Analysis

[Objective] This research aimed to study the FTIR spectra of corn germs and endosperms so as to provide a scientific way for identifying corn of different types. [Method] The corn germs and endosperms of three types were studied by using Fourier transform infrared spectroscopy（FTIR） technology, combined with cluster analysis. [Result] The overall characteristics of original FTIR spectra were basically similar within the range of 700-1 800 cm^-1. The FTIR spectra were mainly composed by the absorption peaks of polysaccharides, proteins and lipids. Within the wavelength range of 700-1 800 cm^-1, there were only tiny differences in original FTIR spectra among the corn germs and endosperms of three different types. The spectra were then processed by using first derivative and second derivative. The second derivative spectra were used for hierarchical cluster analysis（HCA）. The results showed that with the wavelength range of 700-1 800 cm^-1, the second derivative spectra of the 52 samples could be better clustered according to the tree types and corn germ and corn endosperm. The clustering correct rate reached 96.1%.[Conclusion] FTIR technology, combined with cluster analysis, can be used to identify different types of corn germs and endosperms, and it is characterized by convenience and rapidness.

Replacement of Forage Fiber Sources with Dried Distillers Grains with Solubles and Corn Germ Meal in Holstein Calf Diets

This study was carried out to determine the effect of replacement of forage fiber sources from alfalfa and Leymus chinensis with nonforage fiber sources（NFFS） from dried distillers grains with solubles and corn germ meal on calves growth, rumen development and blood parameters. 48 female and 12 male calves（（110.55±15.36） kg of body weight and 12 wk of age） were assigned randomly to four dietary treatments（15 calves/treatment） in a completely randomized design. Experimental diets were： 0% NFFS（control）, 9% NFFS（group 1）, 18% NFFS（group 2）, 27% NFFS（group 3）, and contained equivalent neutral detergent fiber and total digestible nutrients, respectively. The dry matter intake was similar among diets, averaging 3.33 kg d-1, and no differences were detected for body weight, withers height, body length and heart girth. In addition, the development of rumen, reticulum, omasum and abomasum also were similar among diets. Dry matter, crude protein, and neutral detergent fiber digestibilities increased with the increasing levels of NFFS in the experimental diets, but had no significant effect. Blood urea nitrogen, total protein and glubulin were not affected by the dietary treatment, but group 3 resulted in the highest（P〈0.05） concentrations of glucose and the lowest（P〈0.05） concentrations of triglycerides and albumin. In conclusion, dried distillers grains with solubles（DDGS） and corn germ meal（CGM） were available and alternative fiber sources for Holstein calf diets.

Study on Microwave Preparation of Conjugated Linoleic Acid from Corn Germ Oil

[Objective] The optimal craft of preparing conjugated linoleic acid from corn germ oil by dint of microwave method was studied. [Meth- od] Microwave power, microwave mode of action, the amount of catalyst and solvent were selected for single-factor-experiment. Then, based on the single-factor-experiment, the catalyst and solvent amount, and microwave function time were chosen for orthogonal experiment so as to deter- mine the optimal craft of preparing CLA from corn germ oil. UV absorption spectra and infrared absorption spectrum were used to analyse the struc- tural features of natural corn germ oil and CLA. [Resalt] The optimal preparation condition was as follow： the catalyst was 0.6 times heavier than oil, solvent was 3 times heavier than oil weight, microwave worked for ten minutes. Under the optimal condition, CLA was 56.3% and conversion rate was 99.47 %. The results indicated that non-conjugated double bonds of linoleic acid can be isomerized and changed into conjugated double bonds under the conditions of microwave irradiation,[ Conduslon] The study provided a new way for the preparation of CLA.

Determination of the available energy,standardized ileal digestibility of amino acids of fermented corn germ meal replacing soybean meal in growing pig diets

Three experiments were conducted to compare the digestible(DE),metabolizable energy(ME),and standardized ileal digestibility(SID)of amino acids(AA)in fermented corn germ meal(FCGM)and soybean meal(SBM),and evaluate the effects of FCGM replacing SBM in growing pig diets.In Exp.1,18 barrows with initial body weight(BW)of 60.2±3.40 kg were randomly allotted to 3 treatments with 6 replicates per treatment.The control diet used corn as the only energy ingredient,and 2 test diets were made by replacing 25.8%of corn with FCGM or SBM.The DE and ME of FCGM were less(P<0.01)than those of SBM.In Exp.2,18 barrows(59.3±2.52 kg BW)with ileal T-cannulas were randomly allotted to 3 treatments with 6 replicates per treatment.The SID of arginine,tryptophan and proline were greater(P<0.05)and the tyrosine was less(P=0.01)in SBM compared with FCGM.In Exp.3,144 growing pigs(56.1±5.22 kg BW)were randomly allotted to 4 treatments with 6 pens per treatment(3 barrows and 3 gilts per pen).Four diets(FCGM0,FCGM10,FCGM20 and FCGM30)were formulated using FCGM to replace 0%,10%,20%and 30%of SBM,respectively.The ME and SID values of AA of SBM and FCGM were determined by Exp.1 and 2.Results showed that increasing FCGM inclusion quadratically(P<0.05)increased the average daily gain(ADG),average daily feed intake,and the levels of serum immunoglobulin G(IgG)and urea nitrogen,and linearly(P<0.05)increased the serum IgM,the propanoic acid,butyric acid,total volatile fatty acid(VFA)and the Shannon index of microbiota in feces.Besides,the relative abundance of genus Streptococcus in FCGM0,Lactobacillus in FCGM10 and Lachnospiraceae in FCGM30 were increased(P<0.05)compared with other treatments.In conclusion,we recommend replacing 11.80%of SBM with FCGM to obtain the optimal ADG of growing pigs.Moreover,as the ratio of FCGM replacing SBM increased in diet,the immunity,intestinal microbiota and total VFA composition of growing pigs were improved.

制油工艺对玉米胚芽油品质特性及风味成分的作用机制

为探究制油工艺对植物油综合品质及风味的影响,本研究以玉米胚芽为原料,采用酶辅助冷榨法、萃取法和水酶法进行油脂制取,比较分析制油工艺对玉米胚芽油的基本理化特性、抗氧化活性、脂肪酸组成、光谱特征和挥发性风味物质的影响。结果表明:酶辅助冷榨法所得玉米胚芽油酸值、过氧化值均高于其他方法。比较3种方法油脂样品对羟自由基的清除能力,其中酶辅助冷榨法所得玉米胚芽油羟自由基清除能力最强。不同制油工艺对玉米胚芽油中亚油酸和亚麻酸以及不饱和脂肪酸含量影响差异不显著。全光谱分析表明,水酶法所得油脂样品中亚油酸(共轭二烯酸)含量最高。不同制油工艺玉米胚芽油挥发性化合物的组成及相对含量存在明显差别。综上,加工工艺对玉米胚芽油理化特性、抗氧化性、风味物质均会产生影响,本研究可为玉米加工副产物利用和玉米胚芽油适度加工提供理论参考。

玉米胚芽预榨饼浸出中湿粕脱溶的生产实践

在玉米胚芽预榨饼浸出制油过程中,湿粕脱溶是一个很重要的工序。基于玉米胚芽预榨饼的特点,对其浸出过程中湿粕脱溶工艺和设备进行了改进,并应用于生产实践。采用浸出器强制沥干和新型的高料层蒸脱机的技术方案,在强制沥干真空度1500 Pa、蒸脱机脱溶层净高3600 mm、脱溶时间35~40 min条件下,粕残溶达到650 mg/kg及以下,闪爆实验合格。通过采用新工艺和新技术,能在保证玉米胚芽粕产品品质的同时达到节能降耗的目的。

茶多酚-玉米胚芽粕蛋白膜制备及性能研究

以玉米胚芽粕为原料,通过醇法提取玉胚芽粕醇溶蛋白,以丙三醇作为增塑剂,添加壳聚糖提高复合膜液分子间距离,并向其中加入茶多酚,制成复合膜。首先,通过单因素正交试验,研究4个因素对复合膜拉伸强度、水蒸气透过率以及过氧化值指标的影响,以便确定最佳成膜条件,然后,通过测DPPH对其抗氧化性进行分析。试验结果表明:在玉米胚芽粕蛋白浓度为18%、丙三醇添加量为6 g、壳聚糖添加量为0.8 g、茶多酚浓度为2%时,拉伸强度9.24 MPa,水蒸气透过率为2.17 g·mm/(m 2·d·kPa),过氧化值为4.23 meq/kg,所测复合膜的各项指标最佳,且成膜效果最好。同时,由于茶多酚的加入,DPPH高达32.57%,抗氧化性明显提高。向复合膜中加入丙三醇、壳聚糖以及茶多酚,使得复合膜各方面性能优化显著,且有效提高了膜的抗氧化性。

玉米胚芽粕蛋白提取及其在植物复合饮料中的应用

以玉米胚芽粕为原料,研究制备一种高蛋白营养性饮品。通过单因素试验,采用碱溶酸沉法优化玉米胚芽粕蛋白提取工艺参数,再根据正交试验确定最终料液比、pH值、提取时间、提取温度等参数,进一步确定玉米胚芽粕蛋白的最优提取方案。以试验提取的玉米胚芽粕蛋白和腰果为原料,对玉米胚芽粕蛋白、腰果汁、柠檬酸、黄原胶的添加量进行单因素试验和正交试验设计来确定其添加量对玉米胚芽粕蛋白、腰果复合饮料感官品质及稳定性的影响。试验结果表明,以料液比1∶12、pH9、提取时间180 min、提取温度50℃为最终玉米胚芽粕蛋白提取的最佳工艺条件,蛋白提取率为28.15%。复合饮料最佳的制备工艺及配方为玉米胚芽粕蛋白添加量20%、腰果汁添加量15%、柠檬酸添加量0.3%、黄原胶添加量0.25%。该产品色泽鲜亮,香甜适中,均匀稳定,具有玉米、腰果的特殊风味,是一款风味独特,富含营养的复合型饮料。

酶法制备玉米胚芽蛋白基料的酶解条件研究

以玉米胚芽为原料,采用水酶法从玉米胚芽中提取玉米胚芽蛋白基料。通过试验得出,碱性蛋白酶水解玉米胚芽的最佳酶解条件为:酶解温度55℃,pH值9.5,加酶量0.20%,酶解时间4.5 h。此工艺条件下,酶解后水解度达到49.61%。

玉米胚芽酶法辅助低温压榨制油工艺优化

为提升粮食加工副产物玉米胚芽的综合利用价值,以玉米胚芽为原料,以出油率为指标,通过单因素试验和正交试验对玉米油的酶法辅助低温压榨法制取工艺条件进行优化,并对最优条件下制取的玉米油基本理化指标进行分析。结果表明:酶法辅助低温压榨法制取玉米油的最优工艺条件为酶解水分含量12%、纤维素酶添加量0.5%、碱性蛋白酶添加量1.0%、酶解温度45℃、酶解时间6 h、压榨温度60℃、压榨压力50 MPa、压榨时间60 min,在此条件下玉米胚芽的出油率为41.89%,较常规低温压榨的出油率(39.68%)高;所制得的玉米油澄清、透明,呈棕红色,理化指标基本符合三级成品玉米油国家标准。综上,酶法辅助低温压榨工艺可获得品质良好的玉米油,同时出油率较常规低温压榨法有所提高。

喷浆玉米皮、玉米胚芽粕和玉米DDGS的工艺特点及营养价值特性

随着我国畜牧业的迅速发展,人畜争粮矛盾日益凸显,造成饲料资源供不应求。玉米作为最重要的大宗原料之一,含有丰富的营养成分,但近年气候变暖、地缘冲突、新冠疫情蔓延等因素导致我国玉米减产,大量依赖进口,因此应在畜牧业中高效利用玉米副产物等非常规饲料原料。玉米副产物如喷浆玉米皮、玉米胚芽粕、玉米干酒糟及其可溶物(DDGS)等具有较高的营养价值,将其合理应用在畜禽饲料中不仅可以减少玉米原料浪费,丰富原料资源,而且能够降低饲料成本,提高养殖效益。文章就玉米副产物的加工工艺、营养特性以及在畜禽上的应用进行整理总结,以期为玉米副产物在畜禽养殖中的应用提供参考。

水酶法提取玉米胚芽油的研究

在水酶法制取玉米胚芽油的工艺中 ,纤维素酶和中温 α淀粉酶的复合作用能显著提高玉米胚芽油的收率。其最适参数为 :料液比 1∶5 ,蒸汽预处理时间 2 0min ,酶的加入量 0 8% (纤维素酶和淀粉酶的配比为 5∶3) ;反应时间 6h ,提油率可达 89 75 %。

玉米胚芽水酶法提油及蛋白质的回收

采用水酶法从玉米胚芽中提取玉米胚油的同时回收蛋白质,对热处理工艺进一步优化,同时对酶配方进行了研究.结果表明:经过反复解冻冻结的原料浸泡于0.05mol/L的柠檬酸溶液中,112℃处理65min,在酶最适条件下依次加入酸性蛋白酶和纤维素酶,添加质量分数分别为2.5%,1.5%,提油率达到91.0%.纳滤、浓缩、喷雾干燥得到低脂蛋白质和碳水化合物.

玉米胚芽分离蛋白提取工艺研究

利用水、5%Na2SO3、70%C2H5OH和0.4%NaOH溶液,分步提取玉米胚芽中的清蛋白、球蛋白、醇溶性蛋白和碱溶性蛋白,确定各种分离蛋白较佳的提取工艺条件。结果表明:浸提温度40℃,加水量35mL,浸提40min,清蛋白的提取率达39.35%～41.17%;浸提温度40℃,加Na2SO3量30mL,浸提30min,球蛋白的提取率达30.78%～32.67%;浸提温度50℃,加C2H5OH量40mL,浸提20min,醇溶蛋白的提取率达2.87%～2.95%;浸提温度50℃,加NaOH量30mL,浸提30min,碱溶蛋白的提取率达14.79%～15.61%。

尿素包合法纯化玉米油中亚油酸的研究

研究了尿素包合过程中回流时间、包合时间、包合温度、尿素与溶剂配比等主要条件与纯化得到的亚油酸纯度和得率的关系。结果表明,尿素与溶剂配比是影响亚油酸纯度和得率的主要因素。当尿素/乙醇为1∶2(W/V)时,亚油酸的纯度和得率均较高,当混合脂肪酸/尿素/乙醇为1∶3∶6(W/W/V)时,在室温下,通过一次尿素包合就能使亚油酸的纯度从44 48%提高到95 68%,得率为72 41%。

乙醇水溶液提取玉米胚芽油的工艺优化

为了解决水酶法提取玉米胚芽油生产成本高、提取时间长的缺点,该文采用乙醇水溶液作为提取剂提取玉米胚芽油。通过对粒径、料液比、温度、乙醇体积分数、p H值和时间等条件对油在油相、水相和渣相中分布的研究发现,物料粒径和乙醇体积分数对提高清油得率具有显著(P<0.05)的影响,而提取时间对清油得率的影响最小(P<0.05)。在单因素试验的基础上通过正交试验,得出乙醇水溶液提取玉米胚芽油的最佳工艺参数为:物料细粉4次(此时粒径为49.18μm)、料液比1∶7 g/m L、温度70℃、乙醇体积分数30%、p H值9.0、提取时间2 h。在该条件下,清油的得率为94.05%±0.32%,水相含油量为3.49%±0.77%,渣相含油量为2.55%±0.82%。分析乙醇水溶液提取的玉米胚芽毛油酸价、过氧化值和含水率等指标发现,该毛油的质量优于国标规定的玉米原油,并且和压榨一级成品油指标接近,只需要经过简单精炼就可以达到食用油要求。研究结果为乙醇水溶液工业化生产玉米胚芽油提供参考。

水酶法提取玉米胚芽油工艺优化

采用水酶法提取玉米胚芽油并对工艺进行优化。通过单因素试验和正交试验,确定水酶法提取的最佳工艺条件:液料比5:1(mL/g)、复合酶用量2.5%、酶解时间7h、pH6.0,复合酶种类为纤维素酶和α-淀粉酶,添加质量比为4:3。在此条件下,玉米胚芽油提取率为89%。气相色谱对玉米胚芽油进行分析结果表明:油酸、亚油酸含量分别为43.46%及40.22%。

富含γ-氨基丁酸(GABA)玉米胚芽的应用及其GABA提取的研究

分析经富集处理的玉米胚芽的氨基酸组成和含量,摸索了正己烷脱油的适宜条件,并采用超声波法对其中的γ-氨基丁酸(GABA)的提取条件进行了研究,还利用玉米胚芽进行了面包制作应用试验。分析结果显示:玉米胚芽中含有18种以上氨基酸,GABA的干基含量为286.8mg/100g,约占被测氨基酸总量的4.9%。结果表明:脱油的适宜条件为试料:正己烷=1∶4;最佳提取条件为温度50℃,时间2h,料液比1∶6,平均提取量为163.5mg/100g,约占玉米胚芽GABA总含量(271.1mg/100g)的60.3%。经富集处理的玉米胚芽适于制作面包、蛋糕等焙烤制品,其中所含的GABA对热加工较为稳定。

水酶法提油工艺对葵花籽油质量的影响

研究了水酶法提取葵花籽油工艺中热处理工艺参数及酶解过程对葵花籽油酸值、过氧化值、色泽的影响。结果表明:缓冲液的pH、热处理温度、时间对葵花籽油的色泽没有影响,缓冲液pH值对油脂酸值影响不是很明显,但其对过氧化物值影响较大,热处理温度及热处理时间对葵花油酸值、过氧化物值影响较大;酶解过程对葵花油色泽没有影响,对酸值、过氧化物值和脂肪酸组成影响很小,这进一步说明水酶法提取葵花籽油的工艺是可行的。

玉米胚芽肽酶解工艺初步研究

用2709碱性蛋白酶水解玉米胚芽蛋白,以反应温度、pH、加酶量、底物浓度、酶解时间为影响因素,酶解液蛋白质提取率为评价指标,进行单因素分析,并以此为依据采用正交实验设计,通过极差分析确定指标较优的工艺条件。结果表明:温度40℃、pH9.0、加酶量900U/g、底物浓度4.0%时,反应进行4h,胚芽蛋白提取率达85%左右。