Raw Grains Research Articles

Enzymes inhibitory property, antioxidant activity and phenolics profile of raw and roasted red sorghum grains in vitro

Whole grain cereals are important dietary sources for management of metabolic diseases due to the bioactive components they contain. Hence, this study investigated enzymes (pancreatic lipase, α-amylase, α-glucosidase, xanthine oxidase and angiotensin 1-converting enzyme) inhibitory property, antioxidant activity and phenolics profile of raw and roasted red sorghum (Sorghum bicolor) grains in vitro. Extracts of flours of raw and roasted (150 °C and 180 °C, for 20 min) grains were assayed for enzymes inhibitory and antioxidant activities using spectrophotometric methods; while their phenolic constituents were characterized using HPLC-DAD. The raw grains exhibited strong enzymes inhibitory and antioxidant activities, and contained phenolic acids (gallic, chlorogenic, caffeic, ellagic and p-coumaric acids) and flavonoids (quercetin, luteolin and apigenin). However, whereas the enzymes inhibitory activity and levels of the phenolic compounds in the grains decreased significantly (p < 0.05) with increasing roasting temperature, the antioxidant activity increased. Hence, roasting at high temperature may not be recommended for the optimum retention of the enzymes inhibitory property and phenolic compounds of red sorghum grains.

Preservation of vitamins content in Cuccìa using an innovative method of processing

Cuccìa is a traditional Sicilian food prepared by boiling whole durum wheat kernels, in water, for many hours. This process destroys the vitamins E and B contents of crude kernels. It was rated a method to prepare the Cuccìa, preserving the vitamin content. Four varieties of durum wheat were processed comparing the traditional cooking method (TR-boiling for 5/6 hours), and an innovative one (IN-grains scarification, germination, and cooking at 50 °C for 2 hours). On soups obtained the content of biotin, niacin and α-amylase activity were determined. ANOVA showed the cooking method influences biotin and niacin content having values from 0.56 and 0.72 ng ml−1 (raw grain) and values close to 0 (TR), while only a 10% decrease (IN) respectively for both vitamins. On the contrary, α-amylase activity was reduced with IN method. The IN method combined with ancient grains, produces the soup with a good vitamin B amount.

Application on sensory prediction of Chinese Moutai-flavour liquor based on ATR-FTIR

ATR-FTIR combined with chemometrics was applied to establish SVM classification models aiming to evaluate sensory quality of Chinese Moutai-flavour liquor. Transformation of ATR-FTIR data, selection of effective wavenumbers as well as determination of c and gamma were performed in succession, while the verification of models was deployed applying unknown samples. Finally, taste-prediction models of raw grain and cleanliness have an accuracy reaching 90%. Model of after-taste has an accuracy of 80% and others are lower than 70%. As for some flavours, ATR-FTIR and chemometrics technology provided an effective method for quality analysis of Chinese Moutai-flavour liquor.

Influence of Fusarium avenaceum infections on barley malt: Monitoring changes in the albumin fraction of barley during the malting process

Fusarium spp. are ubiquitous field pathogens, which are known to affect quality characteristics of cereals. Infections with Fusarium pathogens in brewing cereals are problematic and augur for a poor malt quality. The negative effects of Fusarium infections are various. Besides causing agronomic losses, kernel discoloration, and the production of several mycotoxins, Fusarium spp. are known to enhance the proteolytic activity of infected barley malt. Enhanced proteolysis can be observed in higher values in free amino nitrogen (FAN) as well as in soluble nitrogen. Previous studies showed that, in recent crop years, the predominant Fusarium spp. detected in European malt was F. avenaceum. This study focuses on the changes in the albumin fraction during the malting process of barley samples artificially infected with F. avenaceum in comparison to uninfected control samples. The barley samples were grown under controlled conditions in a greenhouse, and two different sample types were studied: One was not infected with Fusarium spores whereas the other sample was inoculated during anthesis with a spore suspension of F. avenaceum. Malting trials were carried out in a micromalting facility under defined conditions. To monitor the changes in protein profiles due to Fusarium infection, samples were analyzed at different stages of the malting process: barley (raw grain), poststeeping, postgermination, and postkilning. To evaluate the changes in the protein composition, different fractionation techniques (Osborne fractionation, isoelectric focusing, and capillary gel electrophoresis) were utilized. The albumins of the Osborne fractionation were further analyzed as they represent the main metabolically active proteins. Protein maps of the different malting steps were plotted with a custom-programmed visualization tool for comparing the infected and uninfected samples at each malting step. The results elucidate the changes in the albumin fraction during the malting process and reveal the influence of Fusarium infection on the albumin composition of barley, barley malt, and the intermediate products of malting.

Модель функционирования технологического процесса послеуборочной обработки зерна в отделении приема и предварительной очистки зернового вороха

At present, in many regions of the Russian Federation, post-harvest processing of grain is carried out directly on the farms themselves. Produced grain is mainly used for fodder and seed purposes. This is predetermined by difficult weather conditions, and freshly harvested grain is fed to the post-harvest treatment unevenly, it has high humidity and debris, a significant heterogeneity of seeds by ripeness. Machines and equipment of grain cleaning and drying stations and complexes do not fully comply with the properties of the grain pile, which leads to a decrease in their throughput, disruption of processing, the accumulation of large masses of raw grain heap, lengthening the time of harvest, increased losses and reduced quality seeds. Reception and temporary storage of a pile of grain in aerated receiving bunkers with forced ventilation of the pile causes an improvement in the technological properties of the seeds, a decrease in humidity and grain contamination. The use of aerated bunkers for receiving and temporary storage of a grain heap, increase the energy consumption for grain cleaning and heating of the heap. The reduction of specific energy consumption for the operation “Reception of a grain heap” is possible by optimizing both the design parameters and the operating modes of aerated bunkers. The research of the authors showed that the preliminary drying of the grain heap can improve the productivity of the heap cleaner, improve the flowability of the grain pile, the working conditions of the gravity flow devices and the quality of the preliminary cleaning of the grain. The inclusion of the heat generator in the technology of post-harvest processing of grain and the use of heated air in the operations of receiving and pre-cleaning the grain leads to a decrease in the moisture content and grain contamination, an increase in the supply of heap of grain, as well as to the intensification of subsequent technological operations. The paper presents a model of the functioning of the technological process of post-harvest grain processing in the receiving and pre-cleaning unit of the grain pile.

Brewing with malted barley or raw barley: what makes the difference in the processes?

Malted barley is the main source for fermentable sugars used by yeasts in the traditional brewing of beers but its use has been increasingly substituted by unmalted barley and other raw grain adjuncts in recent years. The incorporation of raw grains is mainly economically driven, with the added advantage of improved sustainability, by reducing reliance on the malting process and its associated cost. The use of raw grains however, especially in high proportion, requires modifications to the brewing process to accommodate the lack of malt enzymes and the differences in structural and chemical composition between malted and raw grains. This review describes the traditional malting and brewing processes for the production of full malt beer, compares the modifications to these processes, namely milling and mashing, when raw barley or other grains are used in the production of wort-a solution of fermentable extracts metabolized by yeast and converted into beer, and discusses the activity of endogenous malt enzymes and the use of commercial brewing enzyme cocktails which enable high adjunct brewing.

Measurement of Rice Grain Dimensions and Chalkiness, and Rice Grain Elongation Using Image Analysis.

Measurements of rice grain dimensions, percent grain chalkiness, and grain elongation used to be tedious and slow due to the manual nature of measurements (e.g., use of calipers to measure grains one at a time) and the subjective nature of scoring based on visual inspection (i.e., chalkiness). Recent developments in imaging technologies have enabled more high-throughput means for measuring physical traits (i.e., grain dimensions and chalkiness) in raw grains and grain elongation by comparing ratio between raw versus cooked rice. The digital images of rice grains are captured through computer scanning and analyzed using software that can calculate area and pixel value statistics of user-defined parameters. The improvements in throughput made possible by the use of imaging technologies will allow faster quality grading of rice varieties. Market quality is usually defined based on the rice grain physical traits (grain size and shape), degree of chalkiness, and the ability of rice to elongate on cooking. In this chapter, the routine methods to measure the physical traits of rice and grain elongation using image analysis are described.

Nutritional composition and popping characteristics of some selected varieties of pearl millet (Pennisetum glaucum)

A comparative study carried out on nutritional and popping qualities of 11 cultivars of pearl millet (Pennisetum glaucum (L.) R. Br.) varieties have showed significant difference in popping yield, with highest mean popping yield of 73.6 %. Final popped product obtained is crunchy and ready-to-eat with proximate composition comprising 11.1% protein, 6.49% fat, 3.49% crude fibers, 3.19% ash, 74.05% carbohydrate and 1.90% moisture. This paper also highlights the significant reduction in phytic acid which comes down from 404.69 mg/100g in raw grains to 261.45mg/100 g in popped grain. Based on popping characteristics and nutritional value five varieties, viz. CZP 9802, PC 443, PC 1201, PC 701 and PC 383 were found to have better popping and nutritional traits and can be exploited for novel product development that will help in diversifying this nutri-grain use and will be beneficial for human health and increase profits to farmers.

Effect of Traditional Household Processes on Iron, Zinc and Copper Bioaccessibility in Black Bean (Phaseolus vulgaris L.).

Micronutrient deficiencies are a major public health problem. Beans are an important plant-based source of iron, zinc and copper, but their absorption is reduced in the presence of anti-nutrients such as phytates, polyphenols and tannins. Soaking and discarding the soaking water before cooking is unanimously recommended, but this can result in mineral loss. Data on the consequences for mineral bioaccessibility is still limited. This study aimed to evaluate iron, zinc and copper bioaccessibility in black beans cooked (regular pan, pressure cooker) with and without the soaking water. For that, three batches of black beans were investigated in triplicate, each split in nine parts (raw grains and four different household processes in duplicate) and analyzed by applying the quarter technique, resulting in a grand total of 164 samples. Minerals were quantified by ICP-MS (inductively coupled plasma mass spectrometry), myo-inositol phosphates (InsP5, InsP6) by HPLC (high-performance liquid chromatography) ion-pair chromatography, total polyphenols using Folin-Denis reagent and condensed tannins using Vanillin assay. Mineral bioaccessibility was determined by in vitro digestion and dialysis. All treatments resulted in a statistically significant reduction of total polyphenols (30%) and condensed tannins (20%). Only when discarding the soaking water a loss of iron (6%) and copper (30%) was observed, and InsP6 was slightly decreased (7%) in one treatment. The bioaccessibility of iron and zinc were low (about 0.2% iron and 35% zinc), but copper presented high bioaccessibility (about 70%). Cooking beans under pressure without discarding the soaking water resulted in the highest bioaccessibility levels among all household procedures. Discarding the soaking water before cooking did not improve the nutritional quality of the beans.

Profile of major and emerging mycotoxins in sesame and soybean grains in the Federal Capital Territory, Abuja, Nigeria

The spectrum of major and emerging mycotoxins in sesame and soybean grains from the six zones of the Federal Capital Territory (FCT), Abuja, Nigeria was determined using Liquid Chromatography/Tandem Mass Spectrometry (LC-MS/MS). A total of 47 samples (24 sesame and 23 soybean were collected from farmers’ stores. Seven regulated mycotoxins in sesame and five in soybean including aflatoxin B1 (AFB1), aflatoxin B2 (AFB2) and fumonisin B1 (FB1) were detected. However, concentrations were generally lower than regulatory limits set in the EU for raw grains with the exception of ochratoxin A (OTA) exhibiting a maximum concentration level of 23.1 µg kg-1 in one of the soybean samples. This is the first report concerning the contamination of sesame and soybean in Abuja, FCT-Nigeria with the emerging mycotoxins addressed by recent European Food Safety Authority (EFSA) opinion papers totalling 10 in number. These include beauvericin (BEA), moniliformin (MON), sterigmatocystin (STE), altertoxin-I (ATX-I), alternariol (AOH), alternariol methylether (AME) though at relatively low µg kg-1 range. This preliminary data indicate that sesame and soybean might be relatively safe commodities in view of the profile of mycotoxins. DOI: http://dx.doi.org/10.5281/zenodo.1307184

Importance of Zinc for Arabica Coffee and Its Effects on the Chemical Composition of Raw Grain and Beverage Quality

Zinc is essential for the synthesis of amino acids, carbohydrates, and proteins, which are directly related to the chemical composition of raw coffee (Coffea arabica L.) beans, and it may influence the quality of the beverage. This study aimed at evaluating the influence of Zn doses on the chemical composition of coffee beans and beverage quality. Increased Zn availability in the growth medium maximized attributes related to beverage quality, such as polyphenol oxidase activity, color index, and contents of sucrose, caffeine, and trigonelline, reaching maximum values in plants with Zn leaf contents within the sufficiency range of 8.0 to 12.7 mg kg−1. Zinc doses lower or higher than the one that provided maximum quality (∼2 μmol L−1 in nutrient solution) increased the attributes related to loss of beverage quality, such as content of total phenols, 5‐caffeoylquinic acid, leached K, and electrical conductivity. Zinc supply influences the quality of coffee beans, having a positive effect on polyphenol oxidase activity, color index, and contents of sucrose, caffeine, and trigonelline. Adequate Zn doses reduce total phenol content, 5‐caffeoylquinic acid, leached K, and electrical conductivity. The leaf contents, which related to the minimum or maximum points of the quality attributes studied, varied between 8.0 and 12.7 mg Zn kg−1.

Integrated Process for Extraction of Wax as a Value-Added Co-Product and Improved Ethanol Production by Converting Both Starch and Cellulosic Components in Sorghum Grains

Grain sorghum is a potential feedstock for fuel ethanol production due to its high starch content, which is equivalent to that of corn, and has been successfully used in several commercial corn ethanol plants in the United States. Some sorghum grain varieties contain significant levels of surface wax, which may interact with enzymes and make them less efficient toward starch hydrolysis. On the other hand, wax can be recovered as a valuable co-product and as such may help improve the overall process economics. Sorghum grains also contain lignocellulosic materials in the hulls, which can be converted to additional ethanol. An integrated process was developed, consisting of the following steps: 1. Extraction of wax with boiling ethanol, which is the final product of the proposed process; 2. Pretreatment of the dewaxed grains with dilute sulfuric acid; 3. Mashing and fermenting of the pretreated grains to produce ethanol. During the fermentation, commercial cellulase was also added to release fermentable sugars from the hulls, which then were converted to additional ethanol. The advantages of the developed process were illustrated with the following results: (1) Wax extracted (determined by weight loss): ~0.3 wt % of total mass. (2) Final ethanol concentration at 25 wt % solid using raw grains: 86.1 g/L. (3) Final ethanol concentration at 25 wt % solid using dewaxed grains: 106.2 g/L (23.3% improvement). (4) Final ethanol concentration at 25 wt % solid using dewaxed and acid-treated grains (1 wt % H2SO4) plus cellulase (CTec2): 117.8 g/L (36.8% improvement).

Fatty Acids Profile of Coffea arabica L. Resistant to Leaf Rust Grown in Two Environments of Minas Gerais, Brazil

The quality of the coffee drink is defined by its sensorial attributes which are developed through the chemical predecessors found on raw grains. Due to this relation, this present work had a goal evaluating the sensorial characteristics of resistant coffee cultivars to leaf rust for the production of specialty coffee and correlate them with the profile of fatty acids present on raw grains, enabling the distinction of cultivars in two environments of Minas Gerais. For this purpose, seven cultivars of Coffea arabica resistance to leaf rust were evaluated and two susceptible cultivars, in two growing environments: Lavras, in the South of Minas Gerais and Patrocínio, in the Cerrado of Minas Gerais. The C16:0, C16:1, C18:0, C18:1, C18:2 w-6, C18:3 w-3 fatty acids common in coffee grains, were identified in the cultivars. The presence of an acid uncommon in coffee grains, the gamma linolenic acid (C18:3 w-6, GLA) was also detected. The palmitic and alpha linolenic fatty acids presented correlation with the sensorial quality of the drink. The linoleic, palmitic, alpha linolenic and gamma linolenic fatty acids were capable to differentiate the Patrocinio and Lavras environments. The profile of the fatty acids permitted differentiate the leaf rust resistant cultivars, the environments as also the interaction between these two matters related to the sensorial quality.

Whole genome sequencing-based association study to unravel genetic architecture of cooked grain width and length traits in rice

In this study, we used 2.9 million single nucleotide polymorphisms (SNP) and 393,429 indels derived from whole genome sequences of 591 rice landraces to determine the genetic basis of cooked and raw grain length, width and shape using genome-wide association study (GWAS). We identified a unique fine-mapped genetic region GWi7.1 significantly associated with cooked and raw grain width. Additionally, GWi7.2 that harbors GL7/GW7 a cloned gene for grain dimension was found. Novel regions in chromosomes 10 and 11 were also found to be associated with cooked grain shape and raw grain width, respectively. The indel-based GWAS identified fine-mapped genetic regions GL3.1 and GWi5.1 that matched synteny breakpoints between indica and japonica. GL3.1 was positioned a few kilobases away from GS3, a cloned gene for cooked and raw grain lengths in indica. GWi5.1 found to be significantly associated with cooked and raw grain width. It anchors upstream of cloned gene GW5, which varied between indica and japonica accessions. GWi11.1 is present inside the 3′-UTR of a functional gene in indica that corresponds to a syntenic break in chromosome 11 of japonica. Our results identified novel allelic structural variants and haplotypes confirmed using single locus and multilocus SNP and indel-based GWAS.

Enhanced Production of &amp;#945;-Amylase from &lt;I&gt;Bacillus licheniformis&lt;/I&gt; SKB 4

The effect of some inductive factors including incubation temperature, aeration, inorganic phosphate source, supplementation of amino acids and vitamins on production of extracellular amylase by Bacillus licheniformis SKB 4 was optimized in a submerged fermentation. The maximum production of enzyme was obtained in highly aerobic condition at 42°C, pH 6.5 and 24 h incubation period. 1%, v/v inoculumn concentration exerts best result for growth and enzyme production. Several chemical factors such as inorganic phosphate (KH 2 PO 4 ; 0.3%), amino acids (0.5 mg %; glutamic acid, cysteine, isoleucine), vitamins (biotin, 50μg/ml; pyridoxine, 50μg/ml; riboflavin, 20μg/ml), metallic salt MgSO 4 (1 mM) and surfactant Tween 80 (0.075% (v/v) have positive effect on amylase production. Among the raw food grains used for amylase production, soya bean seed favoured enzyme production and rate production is much higher (2.5 fold) than the normal culture medium, whereas cereals and other pulses have no effect on enzyme production within normal incubation time. Use of raw food grain as culture medium and optimization of certain factors are the most important part for production of amylase in industrial sector.

Susceptibility of Tribolium castaneum and Trogoderma variabile larvae and adults exposed to methoprene-treated woven packaging material

Methoprene is an insect growth regulator (IGR) registered in the United States for direct application to stored raw grains, as an aerosol or residual contact insecticide, and for use as a coating for protection of packaged products. A series of tests was conducted to determine the adverse effects of short term exposure, sub-lethal exposure, and continual exposure of the red flour beetle, Tribolium castaneum (Herbst) and warehouse beetle, Trogoderma variabile Ballion, on methoprene-treated woven packaging material at 27 and 32 °C and 60% r.h. In the first test, larvae of both species were added to individual arenas and exposed for different time intervals, removed and resulting adult emergence was assessed. In the second test, eggs of both species were exposed on the packaging surfaces to determine percent egg hatchability. In the third test, adults of T. castaneum and T. variabile were added to arenas and held for 7 and 3 d, respectively, to determine number of eggs laid per female and subsequent egg hatchability. The eggs were held in arenas to determine the effect of continual exposure on egg-to-adult emergence. Results showed normal adult emergence decreased with increasing exposure time and temperature. Exposure to methoprene-treated packaging did not adversely affect fecundity of T. variabile adults, but did affect fecundity of T. castaneum. Continual exposure gave 100% suppression of T. castaneum adult emergence and a reduction of T. variabile emergence. This study indicated that methoprene-treated packaging could be a valuable addition to an existing integrated pest management program to increase protection of packaged products.

Phenolic Acids Profiles and Cellular Antioxidant Activity in Tortillas Produced from Mexican Maize Landrace Processed by Nixtamalization and Lime Extrusion Cooking.

Phenolic acids profiles, chemical antioxidant activities (ABTS and ORAC), as well as cellular antioxidant activity (CAA) of tortilla of Mexican native maize landraces elaborated from nixtamalization and lime cooking extrusion processes were studied. Both cooking procedures decreased total phenolics, chemicals antioxidant activity when compared to raw grains. Extruded tortillas retained 79.6-83.5%, 74.1-77.6% and 79.8-80.5% of total phenolics, ABTS and ORAC values, respectively, compared to 47.8-49.8%, 41.3-42.3% and 43.7-44.4% assayed in traditional tortillas, respectively. Approximately 72.5-88.2% of ferulic acid in raw grains and their tortillas were in the bound form. Regarding of the CAA initially found in raw grains, the retained percentage for traditional and extruded tortillas ranged from 47.4 to 48.7% and 72.8 to 77.5%, respectively. These results suggest that Mexican maize landrace used in this study could be considered for the elaboration of nixtamalized and extruded food products with nutraceutical potential.

Extrusion Processing of Amaranth and Quinoa into Gluten-Free Snack Foods for Celiac and Gluten-Free Diets

Because of the growth of gluten intolerance and Celiac disease, there is growing interest in development of gluten-free foods. Beyond just being gluten-free, such foods can also have other positive nutritional benefits to human health. Extrusion processing is commonly used to produce a wide variety of human food products. Gluten-free grains can be a processing challenge, however, due to lack of proper binding, which can lead to poor quality food products. This research explores how extrusion parameters impacted the quality of amaranth- and quinoa-based extrudates. The specific objectives of this project included extruding each of the grains, then measuring extrudate properties, such as color, unit density, expansion ratio, and durability. Both the quinoa and amaranth were extruded as raw grain, as well as ground to 2mm and 1mm particle sizes. Other experimental conditions included moisture contents of 20% and 40% (d.b.), and extruder screw speeds of 50 rpm and 100 rpm. All treatments were successfully extruded, and all extrudates had high quality attributes, making this the first time either quinoa or amaranth was extruded without any binding ingredients. This study provides information useful for commercial scale-up.

Apparent digestibility coefficients of European grain legumes in rainbow trout (Oncorhynchus mykiss) and Nile tilapia (Oreochromis niloticus)

Two trials were carried out to evaluate the apparent digestibility coefficients (ADCs) of dry matter (DM), crude protein (CP), lipids, starch and gross energy (GE) of six European varieties of grain legumes, namely chickpea-type Kabuli (CHK), chickpea-type Desi (CHD), field pea (FP), faba bean (FB), white lupin (WL) and chickling vetch (CV), in rainbow trout and Nile tilapia juveniles. The ADCs were measured using a reference diet and six experimental diets (700 g/kg of the reference diet and 300 g/kg of each raw grain legume) containing 10 g/kg chromic oxide as inert marker. Additionally, grain legumes were analysed for the organic acids profile. In rainbow trout, FP presented the highest ADCs of DM, CP and GE, whereas chickpeas and FB had the lowest DM, GE and starch ADC values. In Nile tilapia, the lowest values of nutrients (except starch) and energy ADCs were found for FP and CV. Nutrients and energy of chickpeas, WL and FB were better digested by tilapia, whereas FP was better digested by trout. Overall results reveal raw grain legumes as promising feed sources for both fish species.

Effect of Digestive Enzyme Treatment on Antioxidant Properties of Germinated Green Gram Fortified with Minerals

The antioxidant activity (AA) of green gram germinated in mineral‐fortified water (with iron at 100 or 200 mg/100 mL or zinc at 50 or 100 mg/100 mL), cooked under pressure (PC), or microwaved and subjected to digestive enzyme treatment was determined by using three assay methods. Total AA showed that dehulled grains (DG) had higher AA than whole grains (WG). Cooking reduced the AA in both methods compared with raw grains with a lower percent retention of AA, although significant variations were not found between methods. The percent retention of AA in postdigestion samples was 22.68–51.39 (DG) and 15.67–44.0 (WG). Free radical scavenging activity indicated a different pattern, in which WG exhibited higher AA than DG and, among cooking methods, PC grains had higher activity. A reducing‐power assay showed similar results: DG had lower and PC samples had higher AA. Postdigestion AA of WG was higher for cooked than raw samples, although DG showed the opposite trend. In all cases, samples fortified with iron showed less AA because of prooxidant action of iron. In all assays, postdigestion samples had less activity than predigested extracts. In conclusion, germinated grains showed high AA, influenced by the presence of minerals, dehulling process, and cooking.