Yield and functional properties of air-classified protein and starch fractions from eight legume flours

Eight legumes were pin-milled and air-classified into protein (fine) and starch (coarse) fractions and their functional properties compared with those of soybean and lupine flours. The fine material which represented 22.5 to 29% of the original flours contained from 29 to 66% protein as well as a high proportion of the flour lipids and ash. The coarse material contained 51 to 68% starch and much of the crude fiber which was dense and concentrated in the starch fraction. Generally legumes which showed highly efficient starch fractionation gave lower recoveries of protein in the fine material. High values for oil absorption, oil emulsification, whippability and foam stability were characteristics of the protein fractions, while starch fractions gave high water absorptions, peak and cold viscosities. Gelation occurred in both air-classified fractions. Pea and northern bean, chickpea and lima bean flours, and airclassified fractions gave generally higher values in the functional property tests, while fababean, field pea, mung bean and lentil gave high protein fractionation in the air classification process.     

Influence of roasting conditions on fatty acids and oxidative changes of Robusta coffee oil

The aim of this study was to determine the influence of roasting conditions, including elevated humidity of air used in the process, on the properties of coffee oil. Beans of Robusta coffee were roasted in a laboratory convective roaster with a possibility of changing the temperature, humidity, and velocity of roasting air. Roasting temperatures from 190 to 216°C, air humidity from 0.07 to 1%, and air velocity of 0.5 and 1 m/s were used. Parameters analyzed in roasted beans were: oil content, fatty acids composition, including trans fatty acids using the GC/FID method and indicators of oxidation level, namely peroxide value and content of conjugated dienes and trienes. Also a thermal profile of oil with the use of the DSC method and finally the bean aroma were evaluated. For maintaining the maximal amount of PUFA, the most favorable roasting conditions were, either, roasting at relatively high temperature and short time, or roasting at low temperatures. Using moderately high temperature resulted in the highest oxidative changes, but on the other hand, the aroma of received beans presented the best sensory properties. For the best nutritional properties, the best roasting conditions were: temperature 210°C and 1% humidity content in roasting air at 1 m/s flow velocity. In such conditions roasted beans obtained a very high quality aroma, and the roasting time was relatively short. Practical applications: This research concerns the quality of oil obtained from roasted coffee beans. The composition of coffee oil changes slightly during roasting, but nevertheless it might be a source of peroxides and trans fatty acids in human diet. In industrial processing coffee oil is extracted from the remains left over from instant coffee production, and it is a popular agent for aromatizing food products. Thus, in this kind of processing, roasting conditions that limit the unfavorable changes of coffee oil should be used.     

磷石膏和钾长石制硫酸钾的试验研究

萃取磷酸生产中副产的大量固体废弃物磷石膏已成为制约磷复肥工业发展的重要因素.针对我国可溶性钾矿资源严重匮乏,而钾长石储量丰富,指出了利用磷石膏与钾长石生产硫酸钾具有现实意义.试验研究了 KAlSi3O8—CaSO4—CaCO3体系的配料比、焙烧温度、焙烧时间、助剂、焙烧样粒度对焙烧产物中 K2O收率的影响,确定了在 n(KAlSi3O8)∶n(CaSO4)∶n(CaCO3)=2∶1∶6配料比下,最适宜的工艺条件为:焙烧温度1000℃、焙烧时间2.0h、助剂 Na2SO4用量为反应物料总量的7%,焙烧产物粒度为74~84μm(180~200目),钾长石中 K2O收率达90%以上.     

Microwave roasting and phospholipids in soybeans (Glycine max. L.) at different moisture contents

The effects of microwave roasting on phospholipids in soybeans were investigated in relation to moisture. Whole soybeans at different moistures (9.6, 38.2, and 51.9%) were roasted by exposure to microwaves at a frequency of 2,450 MHz. During microwave treatments, the lower the moisture content, the higher was the internal temperature in soybeans at the end of microwave roasting. Total lipids were extracted from the beans after microwave treatment, and the phospholipids were separated with thin-layer chromatography. Phosphatidylcholine was the principal phospholipid in the extracted lipids from all unroasted and roasted bean samples. After microwave roasting, phospholipids containing an amino group, especially phosphatidylethanolamine, decreased substantially (P<0.05) in lower-moisture soybeans. However, increasing the moisture content depressed a rise in the internal temperature of soybeans and prevented a reduction in phospholipids and/or polyunsaturated fatty acids in the phospholipids. Based on the changes in the composition and fatty acid distribution of phospholipids in soybeans during microwave roasting, it is necessary to consider the moisture content in soybeans when roasting in a microwave oven.     

Formation of Benzo(a)pyrene in Sesame Seeds During the Roasting Process for Production of Sesame Seed Oil

The main aim of this research was to enhance the understanding of the formation mechanisms of benzo(a)pyrene (BaP) during roasting of sesame seeds (SS). BaP levels in hot‐ and cold‐pressed sesame seed oil (SSO) were evaluated to correlate oil technology and BaP formation. Extracted principal components from SS were roasted either singly or in mixtures at 230 °C for 30 min. BaP was measured by HPLC with fluorescence detection. The results showed that BaP levels in hot‐pressed SSO were significantly higher than those in cold‐pressed SSO (p < 0.05), BaP formation mostly occurred during SS roasting and increased with roasting temperature (between 80 and 280 °C) and time (from 10 to 50 min). Furthermore, the BaP level in the roasted hulled SS (3.64 μg/kg) was higher than it was in roasted whole SS (1.63 μg/kg). The maximum BaP level observed (5.03 μg/kg) was detected in a roasted mixture of SS protein and SSO. The addition of sesame protein to protein‐free SSO promoted the formation of BaP, which suggests that the pyrolysis products of protein and triacylglycerols are probably important precursors in BaP formation.     

惰性气氛下电解锰渣高温还原焙烧脱硫

电解锰渣的化学成分与水泥的组成符合，但高含硫量限制了其在水泥生产中的掺量。本研究采用高温还原焙烧法脱除电解锰渣中的硫，以焦炭为还原剂，在氮气气氛中以不同条件对电解锰渣进行热分解生成SO₂。用扫描电镜（SEM）和X射线衍射（XRD）分析固体产物，气体分析仪分析SO₂的释放，高温还原焙烧法脱除电解锰渣中的硫，探究焙烧温度和焦炭添加量对焙烧产物的物相和硫含量的影响。实验结果表明，生成SO₂的最佳条件为焦炭添加量4％、分解温度1000℃。在最佳条件下，SO₂的最大浓度为3513mg/m³，可用于生产硫酸。焙烧固体产物在温度为900℃、焦炭添加量为4%添加时，SO₃含量可以降低到2.17％。根据GB175—2007《通用硅酸盐水泥》中规定，满足水泥中SO₃含量须低于3.5%的要求，电解锰渣还原焙烧产品可以作为水泥原料，为电解锰渣的资源化综合利用提供理论依据和技术参考。     

Flour of hard bean (Phaseolus vulgaris) in the preparation of bread]

In order to utilize hardened beans, we proposed to find the method most indicated for the preparation of bean flour to determine their nutritional value, and to make bread of high industrial, nutritional quality, and good sensory characteristics, using blends of bean and wheat flours. Two types of flour were prepared, testing four soaking temperatures (22, 30, 40 and 50 degrees C) and two methods to remove the testa (under moist and dry conditions). At laboratory level, the dry testa removal method gave the best flour yields (mean = 85.8%) and the highest protein content (mean = 23.7%). Comparison between soaking temperature at 30 and 50 degrees C was not significant (alpha = 0.05). At pilot plant level, with soaking at 50 degrees C the flour yields were 58.0% for moist testa removal (H1) and 74.0% for dry removal (H2), with a protein content of 22.6% for H1 and 23.0% for H2. The H1 and H2 flours were added to wheat flour at 5, 10 and 15% for bread making. The addition of 5.0% gave breads with similar protein content and sensory characteristics to those of the control, wheat. A diet based on bean-flour bread resulted in greater weight gains than that with casein for gold hamsters. The study also demonstrated the importance of heat-treating of the bean flours, because when flour without previous heat treatment was administered, the animals lost weight and died. This effect was overcome by the process of baking the flours at 140 degrees C for four hours.     

Soy flour in European-type bread

Effect of soy flour, soy protein concentrate, and isolate on dough and loaf properties of breads produced from flour, yeast, salt, and water with no shortening or added improvers was investigated. Wheat flour, rye flour, and mixtures of the two were included in the studies. Three wheat flours, varying in baking quality and extraction, ash content 0.65 and 0.80%, were used; 1.5, 3, and 5% soy products, flour basis, were added. Water absorption increased 3.8–4.7% at the 3% soy level and 6.1–7.3% at the 5% level of soy product addition. Dough development time and stability were increased and dough softening reduced. Dough gassing power increased ca. 7–25%. By using a shorter proofing time, more intensive mixing, and the sponge dough process, loaves only slightly smaller in volume than the control were obtained at the 3% soy level. Panel evaluations scored bread highest with 1.5 or 3% soy flour and that with 3 or 5% soy protein concentrate as lowest, but acceptable. Use of 2% lard as shortening, or 2% lard plus emulsifier, produced soy breads of excellent quality and ca. 25% higher loaf volume than controls.     

Effects of processing by granular heated beds on the chemical and functional properties of legume grains

The present research compares the effect of cooking cowpea, canavalia and lupine by pressure cooking and by a granular bed roaster, on chemical and physical characteristics. The wet cooking process was carried out by pressure cooking at 121 degrees C for 30 min at 15 psi, using a bean-to-water ratio of 3 to 1. The cooked samples were dried with heated air (60 degrees C). The granular bed roasting was carried out at 200 and 250 degrees C for contact times of 2 and 2.5 minutes, at a 5 to 1 sand:bean ratio. For this process, a granular bed roaster was designed and constructed. This process induced in the grain temperatures which varied from 90-128 degrees C, and thermic efficiencies which fluctuated between 38 and 60%. The wet and the dry processes did not affect protein and fat content, although available lysine values decreased slightly. The two processes did not affect water absorption and water solubility. The nitrogen solubility index, however, decreased as roasting temperatures increased in the case of the granular bed roaster, and it also decreased in the wet-cooking procedure. Both processes affected color of the cooked flours, with a light orange color, suggesting non-enzymatic browning due to the high temperatures used.     

Antioxidant Activities and Phenolic Compositions of Wheat Germ as Affected by the Roasting Process

Wheat germ is a good source for wheat germ oil, and it is a by‐product with highly concentrated nutrients from the wheat flour‐milling industries. In the present study, raw wheat germ was firstly heat‐treated at 180 °C for 20 min in a fluidized bed dryer, and further roasted at 180 °C for different periods of time. Roasting influence on total phenolic content (TPC), antioxidant activities, and phenolic compositions of wheat germ were evaluated. The roasting process significantly increased the TPC and antioxidant activities including free radical scavenging against DPPH and ABTS radicals, FRAP, and ORAC. In particular, the wheat germ roasted at 180 °C for 20 min showed higher antioxidant activity than those roasted at 180 °C for 5 and 10 min. Three major phenolic acids, namely, ferulic, chlorogenic, and caffeic acid, and four main flavonoids, namely, schaftoside and its isomers or adduct of sinapic acid were identified by HPLC. In general, the content of individual phenolic compounds decreased with prolongation of the roasting time except for ferulic acid. The results suggest that the antioxidant activities of wheat germ can be enhanced by roasting, and the enhancement effect might be partially attributed to the formation of Maillard reaction products (MRP).     

Effect of barley flour and freeze-thaw cycles on textural nutritional and functional properties of cookies

Studies were carried out on cookies prepared by incorporating barley flour (10%, 20%, 30%, and 40%) into wheat flour. The cookies were evaluated for their physical, chemical, nutritional, textural and sensory characteristics. All the cookie samples showed high fiber, mineral and protein contents when compared to those from 100% wheat flour. Incorporation of barley flour improved the color of the cookies from pale cream to golden brown. The cookies became crispier as indicated by the reduction in the breaking strength value from 4.94 to 3.29 kg. Considering the color, taste, flavor, surface appearance of the cookies, 30% incorporation of barley flour was found to be optimum giving cookies containing 1.7% β-glucan, 36.6 ppm iron, 31.8 ppm calcium, 22.9 ppm zinc while the texture characteristics showed that 30% barley incorporated cookies had breaking strength of 4.021 kg lower than wheat cookies and also indicating that the product was nutritionally rich as compared to the 100% wheat flour cookies. The incorporation of barley flour increased the antioxidant properties and polyphenolic content and hence increased functional properties of the cookies compared to the control. The prepared product was safe microbiologically as well as chemically upto 6 months of storage in different packaging materials under varying temperature conditions. The cookie dough contained 30% barley flour and 100% wheat flour (control) was allowed to under go frozen storage and freeze-thaw cycles (freeze for 12 h and thaw for 4 h). After each freeze-thaw cycle, cookie dough was evaluated for its texture profile and also dough was baked to prepare cookie and assessed for its physical, textural and sensory characteristics. It was found that cookies prepared after freeze-thawing of dough were crisper than the normal ones.     

Industrial corn flour enrichment with whole amaranth flour and milling fractions in corn-based products

Whole flour and milling fractions of raw amaranth seeds were used in 90:10, 80:20 and 50:50 mixtures with industrialized corn flour (MINSA) to prepare tortillas and arepas, basic nutritional foods in several Latin American countries. The three corn-amaranth mixtures showed a good protein and fat content as well as amino acid profile, and presented adequate physical characteristics for making tortillas. Amaranth whole flour and commercial corn flour mixtures in the proportion of 80:20 and 50:50 were found suitable for the preparation of arepas. Protein and fat content were substantially improved, with no changes in organoleptic characteristics. The Mexican type of Amaranthus cruentus, selected due to its availability and bromatologic properties, yielded products of excellent nutritional quality, according to their amino acid content and protein efficiency ratio (PER). The protein-rich (1R) and starchy (2-R) fractions obtained by air classification, also yielded good results when substituting amaranth flour. The afore-mentioned flours and air-classified fractions of the 50:50 mixtures proved to be adequate in gruel preparations when used in 1:8 and 1:12 dilutions, as they improved their organoleptic characteristics. Flakes and extrudates were also used, yielding products with a 13.3-15% protein content, 1.7-3.7% fat, and 65.2-74.2% carbohydrates. In addition, extrudates were utilized to prepare snacks of better nutritional quality than existing similar commercial products. Improvement of the tortilla's mineral and fatty acid contents was achieved in every case. Enrichment of this product with whole amaranth flour is, therefore, recommendable for use in programs aimed at improving the nutritional status of the population.     

Effect of Roasting on Flaxseed Oil Quality and Stability

The food industry is interested in the application of roasted flaxseeds because the treatment improves their sensory acceptability. However, it also influences flaxseed oil nutritional quality and stability. The aim of the study was to analyze oxidation changes in situ and in flaxseed oil compounds (fatty acids, phytosterols, tocochromanols) and Maillard reaction products (MRP) after roasting. The effect of the roasting temperature (160–220 °C) and flaxseed cultivars (golden- and brown-seed) was taken into consideration. The results showed that the selection of roasting temperature (<200 °C vs. ≥200 °C) and flaxseed cultivar significantly influenced the nutritional quality and oxidative stability of roasted flaxseed oils. The roasting of flaxseeds did not significantly affect the fatty acid profiles of oil but it influenced the content of the other bioactive compounds. As the roasting temperature increased (≥200 °C), the γ-tocopherol degradation decreased, whereas the content of plastochromanol-8 increased. The total content of phytosterols in the roasted seed samples was higher than in the raw seeds but there was no correlation between the phytosterol content and roasting temperature. The temperature ≥200 °C significantly accelerated in situ oil oxidation during roasting. On the other hand, these conditions favored the MRP formation, which may have slowed down the dynamics of oil oxidation during storage. There was lower oil oxidation in the brown-seed cultivar; in consequence, the tocopherol retention was higher than in the golden-seed cultivars. The results could be useful for the selection of the best cultivars and treatment conditions to decrease unfavorable changes in flaxseed oil nutritional quality and stability.     

机械力作用对钴酸锂硫酸化焙烧产物的影响

目前,研究者仍然不清楚机械研磨处理对从废锂离子电池中获得的钴酸锂（LiCoO2）的硫酸化焙烧的影响。对钴酸锂与一水合硫酸氢钠（NaHSO4·H2O）混合物球磨前后的产物进行热重-差热-质谱（TG-DSC-MS）分析,结果表明球磨处理使焙烧环节焙烧温度降低。对钴酸锂与一水合硫酸氢钠混合物采用不同球磨时间处理后再进行焙烧,对焙烧产物进行X射线衍射分析发现,球磨0.5 h后的焙烧产物中出现了LiNaSO4、Na6Co（SO4）4和Na2SO4。对焙烧产物进行扫描电镜-能谱（SEM-EDS）分析,结果表明焙烧产物形貌不规则,呈大小不同的块状,而且颗粒有团聚现象,氧、硫、钠、钴在整个焙烧产物中呈弥散状态均匀分布。     

Application of Response Surface Methodology to Optimize Roasting Conditions in Cocoa Beans Subjected to Superheated Steam Treatments in Relevance to Antioxidant Compounds and Activities

Roasting is an essential technological process used to produce high-quality cocoa-based products. Response surface methodology (RSM) was employed to optimize the roasting conditions in cocoa beans based on antioxidant compounds (total phenolic, total flavonoids) and their activity (percentage inhibition of 1,1-diphenyl-2-picrylhydrazyl [DPPH] radical and ferric-reducing antioxidant power assay) using two variables: temperature and time. Cocoa beans were roasted at temperature ranging between 150 and 250°C for 10–50 min using superheated steam. The effects of the roasting conditions on the antioxidant properties of cocoa beans were investigated using a second-order central composite design. Results showed that roasting temperature and time significantly affect antioxidants in cocoa beans. Numerical optimization and superimposed contour plots suggested the optimal roasting conditions to be 192°C for temperature with 10 min of roasting time (R ² = 0.99). These conditions can be used for roasting of cocoa beans to produce high-quality cocoa products in terms of antioxidant properties.     

Obtention of a protein concentrate of chickpea (Cicer arietinum) by ultrafiltration]

A protein concentrate was obtained from chick-pea (Cicer arietinum) flour aqueous extract. The factor involved in the recovery of protein were the flour: water ratio, and the pH. The best aqueous extract was subjected to infiltration in a Romicon HF1/2SSS unit equipped with hollow fiber membranes cartridges with a nominal molecular-weight cut-off point of 50,000 daltons. The concentrate was spray-dried and the product obtained had the following composition, expressed in g/100 g: 67.8 protein with 4.9 g/16 g N of reactive lysine; 17.3 fat, 10.0 carbohydrates, and 4.9 ash (dry basis). The nitrogen solubility index was 93 and the color, by Hunter, was L = 86.8.     

Production and functional characteristics of protein concentrates

Protein concentrates derived from common dry beans (Phaseolus vulgaris L.) may improve world protein resources, reduce on-site preparation time and expense and provide improved nutrition. Several different methods have been studied for the production of these concentrates, including alkali extraction and isoelectric precipitation, ultrafiltration, air-classification and salt extraction under high salt concentrations. Recent studies using solid-solid dry roasting, pin milling and air-classification resulted in the following percent mass fractions: hull/fiber (10%), coarse/starch (70%) and fine/protein (20%). Results indicated that the protein fractions were approximately 45–50% protein, low in raffinose and stachyose and hadtrypsin inhibitor activity reduced to about half of that of raw beans. Nitrogen Solubility Index (NSI) ranged from 33–70% and was associated with the thermal conditions applied during dry roasting. The flours had a bland flavor without the bitter off-flavors which have traditionally limited the use of dry beans in formulated foods. Most minerals and phytic acid tended to be associated with protein flour; however, although iron may have been bound to phytic acid, its absorption by anemic rats was not hindered by the presence of endogenous phytic acid. These flours produced acceptable products when incorporated into cookies, doughnust, quick breads and leavened doughs. Presented at the 78th American Oil Chemists' Society Annual Meeting, May 27–21, 1987, New Orleans, LA.     

羰基镍粉焙烧制备高纯度微米氧化亚镍粉体的研究

以羰基镍粉为原料,采用焙烧法制备了氧化亚镍,并将其球磨后得到微米粉体。采用热重-差示扫描量热仪（TG-DSC）研究了羰基镍粉在空气气氛中加热时的氧化行为,利用激光粒度分析仪、等离子体光谱仪、X射线衍射仪（XRD）和扫描电镜（SEM）等分析了样品结构、成分和形貌。结果表明：空气和氧气两种气氛对产物纯度影响不明显。在两种载气条件下,通过优化焙烧温度和焙烧时间（焙烧温度为700 ℃、焙烧时间为2 h、载气流量为1.5 L/min）,羰基镍粉可直接焙烧制备得到纯度为100%、结晶度高的面心立方体氧化亚镍,球磨后得到粒度为4~19 μm的类球形微米氧化亚镍粉末。制备过程具有工艺简单、环境友好的特点。     

Fortification of some Egyptian foods with soybean

Flours from full fat and defatted soybeans were made in the laboratory and used as supplements to Egyptian bread and two popular legume foods (lentil soup and falafil). The effect of fortification level on water absorption, dough rheology, loaf quality, and major chemical constituents of fino (pulp) and Arabic (flat) breads were investigated. Water absorption was slightly affected, dough mixing time, stability, and valorimetric values increased, but the mixing tolerance index decreased by adding defatted soy flour to wheat flour. Loaves were slightly smaller in volume than the control at high levels of defatted soy flour. Morover, bread score and panel evaluation showed deterioration of fino bread characteristics above 6% and Arabic bread above 8% defatted soy flour, but above 3% full fat soy. Organoleptic properties of the enriched lentil soup and falafil were similar to those of control at a level of 25% and 50% full fat soy and of 40% and 60% defatted soy flour, respectively. The most favorable change of the chemical composition of lentil soup and falafil is the increased protein content. Also, increasing the level of defatted soy flour increased ash content and decreased the level of fat absorption by fried falafil. On the other hand, increasing the level of full fat soy may replace the addition of shortening to lentil soup to make it more palatable.     

Technical news feature

Hull-free kernels from confectionary-type sunflower seed were prepressed with two levels of heat treatment and two levels of severity of pressing. Cakes were solvent extracted, desolventized in a continuous, pilot size extractor, and ground into flour. For comparison, kernels were also pressed into flour using direct solvent extraction and desolventizing at room temperature. Qualities of oil and of flour from different treatments were compared. Oils were all of good quality with no differences among treatments. Flours showed no distinct differences in dispersible nitrogen at pH values between 2 and 12, indicating that processing conditions did not damage the solubility of the protein. All cake and flour samples were high in residual hexane, showing the need for a deodorizer in the pilot plant. Treatments did not affect particle size distribution in flours. The flour samples all fell within the range for satisfactory microbiological quality, although bacteria count increased considerably during grinding of cake into flour. Treatments affected dry color but not wetted color of flour, with the more intense heating and pressing producing slightly darker flours. Amino acid compositions were not affected by process treatments.