Sonication Enhanced Cornstarch Separation

Yellow dent corn soaked in deionized water at 52°C for 24 h without addition of SO₂ was wet‐milled using a modified 100‐g laboratory procedure employing ultrasound treatment at different points in the milling process and compared to conventional wet milling and milling‐only corn. Starch yields from ultrasound treatments varied from 66.93 to 68.72% and were comparable to conventional wet milling (68.92%). The ultrasound treated samples produced 6.35 to 7.02 more percentage point starch compared to the milling‐only corn. Compared to the starch from milling‐only corn, the ultrasound‐produced starches showed a significant increase in whiteness and decrease in yellowness that are comparable to starches produced by conventional wet milling. Ultrasound treatment after the second grinding produced the highest starch yield and the lowest protein content in the resulting starch. The ultrasound‐treated starches exhibited different pasting properties as evidenced by higher paste viscosities.     

沙枣替代部分玉米生产乙醇条件的优化

通过单因素试验对玉米沙枣混合原料生产乙醇的条件进行了研究。结果表明,最优产乙醇条件为玉米粉和沙枣粉混合比例为9∶1,料水比1∶4.5（g∶mL）,液化时间60 min,液化酶用量35 U/g,糖化时间30 min,糖化酶用量150 U/g,接种量2%,发酵时间72 h,由马克斯克鲁维酵母单独发酵（Kluyveromyces marxianus）。在上述发酵条件下,混合原料发酵的酒精度可达11.21%vol,比纯玉米粉发酵的酒精度提高了16.77%,残糖量为0.416 g/L,淀粉出酒率和淀粉利用率分别为32.98%和56.44%。     

Utilisation of corn (Zea mays) bran and corn fiber in the production of food components

The milling of corn for the production of food constituents results in a number of low‐value co‐products. Two of the major co‐products produced by this operation are corn bran and corn fiber, which currently have low commercial value. This review focuses on current and prospective research surrounding the utilization of corn fiber and corn bran in the production of potentially higher‐value food components. Corn bran and corn fiber contain potentially useful components that may be harvested through physical, chemical or enzymatic means for the production of food ingredients or additives, including corn fiber oil, corn fiber gum, cellulosic fiber gels, xylo‐oligosaccharides and ferulic acid. Components of corn bran and corn fiber may also be converted to food chemicals such as vanillin and xylitol. Commercialization of processes for the isolation or production of food products from corn bran or corn fiber has been met with numerous technical challenges, therefore further research that improves the production of these components from corn bran or corn fiber is needed. Published 2010 by John Wiley & Sons, Ltd.     

Isolation and Characterisation of Sri Lankan Yeast Germplasm and Its Evaluation for Alcohol Production

Use of inferior yeast cultures represents one of the reasons for low fermentation efficiencies in Sri Lankan alcohol distilleries that use sugarcane molasses. The present study isolated and characterised yeast strains found in natural environments in Sri Lanka and evaluated their performance under laboratory conditions in an effort to select superior strains for industrial fermentations. Yeasts were characterised based on morphological and physiological features such as sugar fermentation and nitrate assimilation. Ethanol production, alcohol tolerance and growth rate of the most promising strains were monitored following laboratory fermentations of molasses. Over a thousand yeast cultures were collected and screened for fermentative activity and a total of 83 yeast isolates were characterised as higher ethanol producers. Most of these belonged to the genus Saccharomyces. Certain strains produced over 10% (v/v) alcohol in molasses media during 72 h laboratory fermentations. Only two strains, SL‐SRI‐C‐102 and 111, showed an appreciable fermentation efficiency of about 90%. The latter strain produced the highest level of ethanol, 11% (v/v) within a 48 h fermentation and exhibited improved alcohol tolerance when compared with the baker's yeast strains currently used in Sri Lankan alcohol distilleries. This study highlights the benefits of exploiting indigenous yeasts for industrial fermentation processes.     

Auswirkungen einer Feuchtkonservierung von Mais auf die Stärkequalität

Effect of Wet-Conservation Technique of Corn on Starch Quality. A corn starch production by German corn is practicable with reservation. Since the moisture content of the cernels varies between 30 and 40% instead of drying two wet conservation techniques were tested. With the experiments of using sodium hydrogensulfite no remarkable differences of quality criteria in comparison with non stored reference starches were observed along with the storage about 24 weeks. The ensiling of corn-cob-mix by a lactic acid fermentation resulted in starches of high quality, too. Consequently these two kinds of wet conservation techniques of storage are suitable in the same manner for starch production.     

The impact of treatment of cereal mashes with hydrolases of non‐starch polysaccharides and pullulanase on the chemical composition of the obtained distillates

The distilling industry has been looking for more efficient technologies for spirit production. The pressureless starch liberation method (PLS) is an energy‐saving alternative to high‐pressure treatment of starch raw materials. Also, one of the promising solutions is the use of supportive enzymatic preparations during the mashing of starch raw materials. Rye and corn mashes obtained by the PLS method were treated with enzymes (pullulanase, xylanase, cellulases and cellobiase). The composition of volatile compounds in the distillates of the fermentation mashes was determined. Acetaldehyde was the dominant aliphatic carbonyl compound found in the raw distillates. Rye‐based fermentation distillates contained small amounts of propionaldehyde, isobutyraldehyde and isovaleraldehyde, which were not found in any of the corn distillates. The treatment of mashes with cellulolytic preparations caused an increase in the methanol content of the obtained distillates. All of the mashes treated with auxiliary enzymes yielded raw distillates with much higher levels of higher alcohols. The application of hydrolases of non‐starch polysaccharides, or pullulanase preparations, during the mashing of the starch raw materials affects the chemical composition of the distillates. Xylanase and pullulanase can be used in the processing of rye and corn mashes for subsequent use in distilled ethanol beverage production. Copyright © 2014 The Institute of Brewing & Distilling     

国外燃料酒精和淀粉加工产品的生产和发展

为了减少对石油的依赖 ,把 12 %的无水酒精 (燃料酒精 )加入汽油 ,2 0 %于柴油中 ,此含氧汽油不再加入四甲基叔丁基醚 ,成为汽车排放废气污染环境少的绿色燃料。　　列举了北美 (美国和加拿大 )燃料酒精厂的规模 ,所用原料、厂址、原料和产品价格的变化。在世界范围内 ,主要产品 (如淀粉、果葡糖浆、酒精等化工产品 )的输出交易量     

利用低温蒸煮工艺进行高浓度酒精发酵

本研究利用低温蒸煮工艺,探讨了玉米淀粉的高浓度酒精发酵。在80℃下对玉米粉进行蒸煮15min,同时加α—淀粉酶进行液化。经冷却后,在55℃下加糖化酶糖化30min。再度冷却到30℃,加酵母菌悬液发酵70h。并利用这一技术研究了产高浓度酒精酵母菌株的最佳发酵条件。在加糖化酶量200～300u/g原料。酵母接种量为3％(v/v),发酵温度为30℃,pH4～4.5,发酵周期为70h,原料水比为1:2条件下,所选用的菌株之一W_4可以产生17.5％(v/v)乙醇。发现该菌株在发酵速度和耐酒精能力方面明显地优于国内酒精厂常用的酵母菌株1300。在发酵结束时,成熟发酵醪的pH值为4.2。外观糖度为0(Bx),残还原糖为0.19％,残总糖为3.6％,淀粉利用率为90％。     

Development of corn starch‐gum bread for phenylketonuria patients

Phenylketonuria (PKU) is an inherited metabolic disease resulting from an enzyme defect that leads to failure to utilize phenylalanine and it is the most common aminoacidopathy in Turkey. There are a considerable number of individuals suffering from PKU and they need special food formulations, but the choice of special foods is limited for these people. Since the bread is the staple food in Turkey, the primary aim of this study was to develop bread formulation and procedure for PKU patients by using materials available in Turkey. To be able to produce low phenylalanine starch‐gum bread, five different commercial food grade gums were added to the corn starch at 1, 2, and 3% addition levels. The addition of surfactant brought about remarkable changes in the starch dough. Loaf of the best overall quality was produced with one of the gums (xanthan gum and carrageenans mixture) at the addition level of 2%, water addition level of 105%, the final proof time of 110 min and the temperature of 30°C when compared with the other gum breads. As a result, a basic formula and procedure for preparing a desirable corn starch‐gum bread was reported for PKU patients.     

Fermentation of Soybean Meal Hydrolyzates with Saccharomyces cerevisiae and Zymomonas mobilis for Ethanol Production

Most of the ethanol currently produced by fermentation is derived from sugar cane, corn, or beets. However, it makes good ecological and economic sense to use the carbohydrates contained in by‐products and coproducts of the food processing industry for ethanol production. Soybean meal, a co‐product of the production of soybean oil, has a relatively high carbohydrate content that could be a reasonable substrate for ethanol production after fermentable sugars are released via hydrolysis. In this research, the capability of Saccharomyces cerevisiae NRRL Y‐2233 and Zymomonas mobilis subsp. mobilis NRRL B‐4286 to produce ethanol was evaluated using soybean meal hydrolyzates as substrates for the fermentation. These substrates were produced from the dilute‐acid hydrolysis of soybean meal at 135 °C for 45 min with 0, 0.5%, 1.25%, and 2% H₂SO₄ and at 120 °C for 30 min with 1.25% H₂SO₄. Kinetic parameters of the fermentation were estimated using the logistic model. Ethanol production using S. cerevisiae was highest with the substrates obtained at 135 °C, 45 min, and 0.5% H₂SO₄ and fermented for 8 h, 8 g/L (4 g ethanol/100 g fresh SBM), while Z. mobilis reached its maximum ethanol production, 9.2 g/L (4.6 g ethanol/100 g fresh SBM) in the first 20 h of fermentation with the same hydrolyzate.     

Starch-entrapped microspheres extend in vitro fecal fermentation, increase butyrate production, and influence microbiota pattern

Previous research has revealed that waxy corn starch which has been entrapped in a matrix of electrostatically cross-linked alginate, shows a slow digestion rate such that much of the starch may reach the colon; thus making this a new type of resistant starch. The purpose of this research was to test the fermentative properties of starch-entrapped microspheres using a batch fecal fermentation method. Fermentation of starch-entrapped microspheres showed significantly lower rates of gas production compared to waxy corn starch, and showed significant increases in total SCFAs during the latter stages of fermentation (24-48 h), whereas waxy corn starch did not. Cooking the starch-entrapped microspheres increased the amount of SCFAs and the molar fraction of butyrate produced during fermentation. Bacterial fingerprinting revealed that uncooked starch-entrapped microspheres have a unique effect on the microbiota that is different from waxy corn starch alone, but cooking causes a shift toward a pattern more closely resembling that of the starch. Starch-entrapped microspheres may deliver slowly fermentable carbohydrate to the colon, with the ability to influence the microbiota. Further human studies are required to determine whether these characteristics occur in vivo.     

不同来源和不同方法提取玉米胚的品质对比研究

从不同玉米深加工企业采集不同提胚工艺生产的玉米胚样品,同时在实验室以优质玉米为原料采用不同工艺提取玉米胚,对玉米胚的主要组分含量、真菌毒素含量、挥发性风味成分及其中油脂品质进行检测分析,对比研究不同来源和不同方法提取玉米胚的品质。结果显示：从玉米淀粉厂所采集玉米胚的纯胚率(60.29%~88.92%)高于从玉米酒精厂所采集玉米胚(42.29%~57.25%),通过风选和筛分可将玉米胚的纯胚率提高至84.11%~97.85%。半干法玉米胚水分含量(9.09%~14.48%)高于湿法玉米胚(3.51%~5.51%),粗脂肪含量(23.63%-26.94%)明显低于湿法玉米胚(53.42%-54.77%),粗蛋白含量(13.75%-18.46%)高于湿法玉米胚(10.10%-12.35%),总氨基酸含量和必须氨基酸含量均高于湿法玉米胚。不同玉米胚毛油的脂肪酸组成和甾醇含量无明显差别,但干法玉米胚毛油中维生素E含量更高。半干法玉米胚中挥发性风味成分(38~46种)明显多于湿法玉米胚(11~36种),感官呈青草味和甜香味,颜色浅且有色泽,湿法玉米胚有哈喇味和刺激味,色泽偏黄且较为暗淡,但湿法玉米胚中玉米赤霉烯酮和呕吐毒素含量更低。以优质玉米为原料采用半干法提取的玉米胚适合做为食用玉米胚的产品开发。     

Production of short‐chain fatty acids following in vitro fermentation of saccharides,saccharide esters,fructo‐oligosaccharides,starches, modified starches and non‐starch polysaccharides

A range of carbohydrates including modified starches and short‐chain fatty acid esters of di‐, tri‐, tetra‐ and polysaccharides were subjected to an in vitro fermentation using human‐derived faecal bacteria. The production of the short‐chain fatty acids (SCFAs) acetate, propionate and butyrate was monitored at 6, 12, 24 and 36 h for all substrates; however, it was found that the proportions of acids produced were reasonably constant after 6 h. Between substrates there was variation in both the proportions and quantities of acids produced. Relative substrate fermentability as measured by total acid production at 24 h was: sucrose octa‐acetate > sucrose > stachyose > pregelatinised starch > Raftilose^® > verbascose > raffinose > starch acetate > bleached starch > phosphated distarch phosphate > locust bean gum > corn starch > oxidised starch = starch sodium octenyl succinate > di‐starch phosphate > acetylated di‐starch adipate = gum arabic > acid‐treated starch > gum tragacanth > gum guar > acetylated di‐starch phosphate = hydroxypropyl di‐starch phosphate > hydroxypropyl starch > pectin > raffinose undeca‐acetate > stachyose acetate > gum karaya = cellulose propionate > cellulose acetate > cellulose > cellulose butyrate > hydroxypropyl methyl cellulose > carrageenan > methyl cellulose. Chemically modified starches were similar to corn starch in the amounts of total SCFAs produced at 24 h. Synthetic sugar esters could have potential application as vehicles to deliver supraphysiological amounts of SCFAs during in vivo studies of colonic fermentation. © 2000 Society of Chemical Industry     

Further purification of food‐grade alcohol to make a congener‐free product

Most alcoholic beverages contain small amounts of chemicals other than ethanol, the congeners. These are byproducts of the fermentation process of the substrate. Congeners are implicated in contributing to hangover (veisalgia) symptoms and it is therefore considered expedient to remove these substances. This research compared 12 established vodka brands with a new product by GC‐MS‐olfactometry. A new vodka produced in Iowa from corn was found to be the purest while another corn‐based vodka and a potato‐based vodka contained eight and 12 impurities each. Eight other commercially available vodkas contained 15–19 impurities and three vodkas showed more than 30 impurities. Neither the raw material nor the country of origin made a difference to the level of the impurities. However, the treatment process was of great importance in terms of reaching lower impurity levels. Multiple distillations and filtration did not seem to benefit the quality, nor did charcoal and activated carbon alone. However, one vodka based on a multiple distilled neutral grain spirit process from corn contained zero measurable volatile impurities. The particular treatment process involved ozonation, followed by granular activated carbon and a nano‐noble‐metal catalysis and adsorption. Copyright © 2015 The Institute of Brewing & Distilling     

玉米渣酿造酱油的新工艺研究

本文对以低脂玉米粉生产淀粉糖浆时产生的废料玉米渣为原料,以沪酿3.042和AS3.350为菌种,采用分开制种曲,混合制大曲,低盐固态发酵和高温短时浸淋方法,酿造特级酱油的新工艺进行了研究,并确定了最佳的工艺条件。     

乙醇溶剂保护法制备非晶颗粒态玉米淀粉

基于乙醇溶剂具有抑制淀粉颗粒膨胀的特性,研究制备非晶颗粒态玉米淀粉的新方法。将玉米淀粉、水与乙醇按不同比例混合并在高温下反应,用偏光显微镜观测处理后的淀粉颗粒结构,结合X射线衍射曲线确认淀粉由多晶态向非晶态的变化。结果表明:当乙醇体积分数为50%,淀粉乳质量浓度为0.25 g/mL时,在85℃条件下反应,可以制备出质量较好的非晶颗粒态玉米淀粉。     

125th Anniversary Review: Fuel Alcohol: Current Production and Future Challenges

Global research and industrial development of liquid transportation biofuels are moving at a rapid pace. This is mainly due to the significant roles played by biofuels in decarbonising our future energy needs, since they act to mitigate the deleterious impacts of greenhouse gas emissions to the atmosphere that are contributors of climate change. Governmental obligations and international directives that mandate the blending of biofuels in petrol and diesel are also acting as great stimuli to this expanding industrial sector. Currently, the predominant liquid biofuel is bioethanol (fuel alcohol) and its worldwide production is dominated by maize‐based and sugar cane‐based processes in North and South America, respectively. In Europe, fuel alcohol production employs primarily wheat and sugar beet. Potable distilled spirit production and fuel alcohol processes share many similarities in terms of starch bioconversion, fermentation, distillation and co‐product utilisation, but there are some key differences. For example, in certain bioethanol fermentations, it is now possible to yield consistently high ethanol concentrations of ˜20% (v/v). Emerging fuel alcohol processes exploit lignocellulosic feedstocks and scientific and technological constraints involved in depolymerising these materials and efficiently fermenting the hydrolysate sugars are being overcome. These so‐called second‐generation fuel alcohol processes are much more environmentally and ethically acceptable compared with exploitation of starch and sugar resources, especially when considering utilisation of residual agricultural biomass and biowastes. This review covers both first and second‐generation bioethanol processes with a focus on current challenges and future opportunities of lignocellulose‐to‐ethanol as this technology moves from demonstration pilot‐plants to full‐scale industrial facilities.     

稻米生产燃料乙醇及副产品综合利用技术研究进展

综述了稻米生产燃料乙醇技术的研究进展,阐述了通过副产品综合利用降低乙醇生产成本的方法。介绍了传统发酵、生料发酵、米糠油的提炼、米蛋白的提取、DDGS／DDG和沼气生产等方面技术的研究进展。     

Macronutrients in Corn and Human Nutrition

As the leading cereal crop in the world, corn (Zea mays L.) plays a significant role in human foods. The focus of this review is on the structures, properties, bioavailability, and health benefits of macronutrients in corn, including its starch, nonstarch polysaccharides, protein, and lipids. With a large number of naturally existent mutants, corn and corn‐based food ingredients with varying macronutrient compositions and different chemical structures and physical properties are commercially available. The corn varieties that have attracted the most interest in human nutrition include high‐amylose, high‐protein, and high‐oil corn. Chemical compositions and molecular structures of starch, nonstarch polysaccharides, protein, and lipids from different corn varieties are comprehensively reviewed here and related to their physical properties, bioavailability, and physiological effects on human health. Particular emphasis is placed upon the impacts of high‐amylose corn flour/starch on postprandial glycemic/insulinemic responses, insulin sensitivity, satiety/appetite, lipid metabolism/obesity, colon health, and mineral absorption. The information presented in this article will be useful for the utilization of corn and the development of corn‐based food ingredients to prepare nutritious food products to improve human health.