Analysis of Variations in the Amylose Content of Grains Located at Different Positions in the Rice Panicle and the Effect of Milling

The results of the presented study indicated that the amylose content (AC) of individual rice kernels varied among grains in the same panicle and even in outer and inner layers of the same grain. The differences among the grains in panicles were 19.1% in the Indica variety “Zhenong 5” and 22.8% in the Japonica variety “Zhehu 9827”. The amylose content of the grains in the upper position or the first branches of panicles and of the early flowering grains or heavier grains was higher than that of others. Amylose content increases by 1.36% in Japonica rice variety “Zhehu 9827” and 1.92% in Indica rice variety “Zhenong 5”, when the degree of milling increases by 10%. The tendency of changes in AC was the same for grains of the Japonica and the Indica rice variety. Furthermore, for analyzing AC the grains in a panicle should carefully be selected. Errors coming from sampling could be decreased by using a multiplicity of grains rather than single‐grain samples.     

Predictive model for grain cracking in terms of rice plant and panicle morphology derived from multivariate analysis

Rice plant and panicle morphology in relation to grain cracking were studied in 17 varieties at four stages of maturity. The data were subjected to principal components analysis in order to identify structure within the data and reduce dimensionality. The first four factors collectively accounted for 72% of the trace. The first factor was dominated by yield and biomass related attributes, and the second with percentage cracked grains and grain moisture-III stage. The projection of varieties onto the planes defined by the first, second, third and fourth factors reflected scattering of varieties over all the quadrants indicating desirable wide variations in the varieties studied, and the results could be generalised. The discussions mainly centred on grain cracking which was primarily influenced by plant height, panicle length, grains/panicle, sequence of grain maturity and the microenvironments—particularly towards the last stages of maturity. Predictive models in terms of the above attributes explained more than 96% of cracking. The role of agronomic practices in controlling grain cracking is discussed. It is indicated that dwarf plants influenced by microenvironment need different panicle morphology and physiological sequence to minimise cracking as compared to tall plants which generally escape the influence of microenvironment.     

Provitamin A and Ascorbic Acid Content of Fresh Pepper Cultivars (Capsicum annuum) and Processed Jalapeños

Alpha and beta carotene, provitamin A activity, dehydroascorbic acid, L-ascorbic acid and total ascorbic acid content of “jalapeño,”“bell,” long green/red “chile,”“serrano” and “yellow wax” peppers (Cupsicum annuum L.) at green and red stages of maturity were determined by HPLC. Effects of thermal processing on vitamin A and C retention in “jalapeno” peppers was also determined. Provitamin A activity ranged from 27.3 to 501.9 Retinol Equivalents (RE/100g). Ascorbic acid concentration ranged from 76.1 to 243.1 (mg/100g). Provitamin A activity and ascorbic acid content increased with maturity in all cultivars. Thermal processing of “jalapeño” cultivars resulted in a 25% decrease of total provitamin A activity and a 75% decrease in total ascrobic acid.     

OXIDATIVE ENZYME ACTIVITIES AND SOLUBLE PROTEIN CONTENT IN LEAVES AND FRUITS OF OLIVES DURING RIPENING

Changes in the content and composition of soluble proteins and the activities of ionically bound peroxidase and polyphenoloxidase in leaves and fruits of olive trees Olea europaea cv. Zard from three regions during “on” and “off” years were evaluated. It was shown that peroxidase and polyphenoloxidase activities were low at early fruit developmental stages, gradually increased and were the highest at full fruit development (120–135 days after fruit set), and remained relatively high throughout ripening and softening stage. Polyacrylamide gel electrophoresis was used for characterization of peroxidase and polyphenoloxidase enzymes in leaf and fruit extracts. Isoenzymes were assessed in extracts from different regions and it was observed that some isoenzymes were only present at full fruit maturity. The protein content and its expression was estimated and characterized, and it was shown that protein content increased during various stages of fruit growth and remained the highest at full fruit ripening. The increase in enzyme activity from leaves and fruits was accompanied by differential expression of isoenzymes and the protein bands between 20 to 37 KDa, that seems to be a marker of full fruit maturity. It was also concluded that in all cases protein content and enzyme activities in leaves and fruits of olive trees during “on” years are considerably lower than those during “off” years.     

Dry and Wet Milling of Malt. A Preliminary Study Comparing Fermentable Sugar,Total Protein,Total Phenolics and the Ferulic Acid Content in Non‐Hopped Worts

In this work, fermentable sugar, total protein, phenolics and ferulic acid content were estimated in sweet worts at different points of lautering. Transfer of these selected malt compounds into worts was analyzed in relation to the method of malt milling (wet milling of malt — the “test worts” or dry milling of malt — the “reference worts”). Glucose, maltose and maltotriose were more rapidly transferred into sweet worts at the early stages of lautering (40 hL and/or 80 hL of wort) after wet milling in comparison to dry milling. Total protein content in the test worts was significantly higher than in the corresponding reference worts at each stage of lautering. Transfer of phenolic compounds and ferulic acid (in the free as well as in the ester form) from the mash into sweet worts was significantly improved by dry milling, but not by wet milling. No difference in the total antioxidant activity was observed between the two types of worts. In conclusion, it can be stated that wet conditioning of malt before milling enhances the fast transfer of fermentable sugars and proteins from the mash into the sweet wort during lautering. Lautering is a time‐consuming process, and time reduction without the loss of wort quality should be a priority. Therefore, wet milling can be of interest to professionals in the field as an interesting alternative method to improve the mashing process.     

Milling breakage susceptibility and mechanical properties of parboiled brown rice kernels

Parboiling, a hydrothermal treatment of paddy or brown rice, impacts both head rice yield and texture and nutritional characteristics of cooked rice. Here, milling breakage susceptibility of parboiled brown rice was investigated on both bulk and kernel level. Brown rice was parboiled by soaking at 40, 55 or 65 °C and steaming at 106, 120 or 130 °C. The breakage susceptibility and changes in starch and proteins of bulk samples were related to the properties of individual rice kernels. An increase in milling breakage susceptibility from 1% to 11% corresponded to a decrease in average bending force of individual kernels from 34.9 to 14.6 N. Furthermore, both white bellies and fissured parboiled rice grains were more breakage susceptible. Their average bending force was respectively 14.1 N and 17.6 N compared to an average of 39.6 N for intact parboiled rice grains. Whereas the level of proteins extractable with sodium dodecyl sulfate containing medium had no impact, the degree of starch gelatinization was critical in determining the presence of both white bellies and fissured parboiled rice grains. More in particular, complete starch gelatinization ensured the absence of white bellies and minimized fissuring in the parboiled end-product, thereby decreasing milling breakage susceptibility.     

Optimization of Process Parameters for Decortication of Finger Millet Through Response Surface Methodology

Decorticated finger millet is prepared by hardening the endosperm by hydrothermal processing and polishing the processed grains. The yield of the decorticated grains is of paramount importance in the millet industry. Milling yield depends on the grain moisture content and incipient moisture conditioning during milling. It was found that steaming conditions such as steaming time and steam pressure significantly influenced the milling yield. Hence, studies were undertaken to determine the influence of moisture and steaming conditions on the yield of decorticated millet. Steaming conditions were optimized through response surface methodology. The responses studied were hardness, milling yield, porosity and water uptake of hydrothermally processed millet. The studies indicated that hydrothermally processed millet with 16±1% moisture content, tempered with 5% added water at I stage and 4% water in the II stage milling, resulted in a yield of 64.6%. The relationship of milling yield, hardness and porosity of the millet was quadratic with the severity of steaming conditions, while water uptake of the steamed millet exhibited a linear relationship. Based on the regression analysis, optimum conditions estimated for steaming time and pressure were 17.5 min and 313.8 kPa, respectively. At this condition, the milling yield, water uptake, porosity and hardness values were also predicted and the values were 68.33 g/100 g, 63.43 g/100 g, 52.23% and 204.01 N, respectively. The studies indicate that steaming the millet at elevated pressure and temperature increases the milling yield and steaming beyond the threshold level has a detrimental effect on the yield of head grains.     

BREAKAGE OF RICE DURING MILLING — COMPARISON AMONG DIFFERENT SHELLERS1

A medium-long, semislender variety of paddy was shelled using four types of shellers (rubber roll, centrifugal, disc under-runner, McGill) followed by pearling with a McGill miller. Grain breakage during shelling was the least in the rubber roll. But the less the breakage during shelling, the more it was during pearling. As a result, the rubber roll gave considerable advantage after low and medium degrees of milling, but only a marginal advantage at high milling. Total rice breakage was equal to or less than the content of defective grains in the original paddy depending on the sheller.     

Influence of seed mycoflora and harvesting conditions on milling,popping and malting qualities of sorghum (Sorghum bicolor)

Four cultivars of sorghum were artificially inoculated with Fusarium moniliforme conidia at flowering and bagged. These samples along with their untreated controls were harvested at physiological maturity and 2 weeks after physiological maturity. The grains obtained from both the treatments were studied for their milling, malting and popping characteristics. Grains harvested at physiological maturity stage possessed superior milling and malting characteristics whereas late-harvested grains exhibited better popping characteristics. Milling and popping reduced the seed mycoflora considerably.     

基于离散元EDEM的米粒破碎特性分析

目的:优化碾米机碾辊转速,减少碾白过程中米粒的碎米率。方法:利用SolidWorks软件建立挤压填充模型,采用EDEM软件中颗粒黏结模型建立单粒米粒以及两粒米粒碰撞接触模型,模拟不同含水率的米粒在不同下落速度下的碰撞过程,观察相应米粒碰撞结果。结果:米粒在碰撞过程中有3种临界状态,分别是完整米粒、轻微破碎米粒、断裂米粒。在设定的含水率范围下,米粒破碎率随着含水率和碰撞速度的增加而增加;单粒米粒和两粒米粒碰撞模型中完整米粒状态的临界破碎速度相近,分别为23.5,22.0 m/s。结论:速度和含水率对米粒破碎形态影响显著,并且在含水率为10.6%下,米粒不破碎能承受的最大速度为22.0 m/s,此时米粒破碎率较小且满足碾白需求。     

Reducing cracking and breakage of soybean grains under combined near-infrared radiation and fluidized-bed drying

Near-infrared radiation was combined with fluidized-bed drying to reduce the cracking and breakage of soybean grains because of its advantages such as a decrease in the moisture gradient and the stresses development within the grain kernel, leading to high quality of product. Physical qualities, i.e. cracking, breakage and colour, were investigated together with microstructure of soybean grains. Protein solubility and urease activity were also determined. The parameters studied were near-infrared radiation powers of 4, 6 and 8 kW, air velocity of 4.5 m/s, air temperature of 40 °C and grain bed depth of 6 cm. Results showed that the drying rate was increased with the increase of near-infrared radiation power. The moisture content was reduced from an initial moisture content of 20% d.b. to the final moisture contents of 13.5% d.b. (4 kW), 12.8% d.b. (6 kW) and 12.5% d.b. (8 kW). The cracking and breakage of soybean grains occurred negligible, which was lower than 4.4% and 5.3% for cracking and breakage, respectively. At near-infrared radiation powers of 4 and 6 kW was accepted for both soybean grains trade and animal feed industries in Thailand. The total colour difference changes (ΔE) were varied in the range of to 2.9-4.2. The protein solubility of final product was in an acceptable range (77-82%) for feed meal. The reduction of residual urease was varied in the range of to 39-70%. This study has demonstrated that the soybean grains under combined near-infrared radiation and fluidized-bed drying was properly treated.     

泸型酒醅物理性质的实验研究

实验测定了酒醅含湿量、乙醇含量、真实密度、堆积密度、空隙率、堆积角和静摩擦系数在窖池中的分布规律.结果表明,随着窖池深度的增加,含湿量从60.2%升高到71.3%,乙醇含量先升高后降低,表层最低为4.1%,中下层最高为6.4%,底层为5.7%;真实密度、松散堆积密度和振实堆积密度随窖池深度增加而增大,其范围分别为747.5kg/m3～913.4kg/m3、374.7kg/m3～443.2kg/m3和529.8kg/m3～580.6kg/m3;堆积角的变化范围是42.8°～45.3°,表层最小、中下层最大;酒醅在生铁、玻璃和木板上的静摩擦系数均随窖池深度增加而增加,其范围分别为0.54～0.58、0.58～0.66和0.69～0.85.研究结果为酒醅混合搅拌及输运设备的设计和蒸馏工艺优化提供了重要参考.     

粳稻粒位间蛋白质及其组分与品质性状间的相关性研究

为了研究不同粒位间籽粒总蛋白质及其4种组分含量与其他品质性状的关系,选用不同稳型粳稻为材料,按照穗部位置分为27个粒位,分析了它们之间的相关性。结果表明,粳稻穗内不同粒位间籽粒的总蛋白质及其4种组分含量与蒸煮食味品质、淀粉RVA谱特征、外观品质和碾米品质都有显著的关系。总蛋白质、醇溶蛋白和谷蛋白含量对食味有显著负面影响,而球蛋白含量对其则有显著正面影响;总蛋白质、清蛋白、醇溶蛋白和谷蛋白含量与直链淀粉含量和胶稠度有负相关性,与糊化温度有正相关性。总蛋白、清蛋白、醇溶蛋白和谷蛋白含量与峰值黏度、热浆黏度、崩解值、透明度和整精米率呈显著或极显著负相关,与消减值、垩白率、垩白度呈显著或极显著正相关;球蛋白表现规律则与之相反。粳稻不同粒位间籽粒的总蛋白质及其4种组分含量与RVA谱4个特征值、蒸煮食味品质和垩白性状的关系表现最为密切。     

Recycling coffee grounds and tea leaf wastes to improve the yield and mineral content of grains of paddy rice

BACKGROUND: Coffee grounds and tea leaf wastes exhibit strong affinity for metals such as Fe and Zn. The objective of this experiment was to evaluate the effect of top‐dressing application of Fe‐ and Zn‐enriched coffee grounds and tea leaf wastes at the panicle initiation stage on the mineral content of rice grains and the yield of paddy rice. RESULTS: The Fe and Zn contents of brown rice grains increased significantly on application of both coffee and tea waste materials. The concentration of Mn was increased by top‐dressing application of coffee waste material only. For Cu, no significant (P < 0.05) differences were found between the control and ferrous sulfate/zinc sulfate treatment. The application of coffee and tea waste materials led to a significant (P < 0.05) increase in the number of grains per panicle, which was reflected in increases in the total number of grains per hill and in grain yield. CONCLUSION: The top‐dressing application of these materials is an excellent method to recycle coffee grounds and tea wastes from coffee shops. Use of these novel materials would not only reduce the waste going to landfill but would also benefit the mineral nutrition of rice consumers at low cost by increasing Fe and Zn levels of rice grains as well as grain yield. Copyright © 2011 Society of Chemical Industry     

Flavonoids and Antioxidant Activity of Fresh Pepper (Capsicum annuum) Cultivars

Flavonoid, ascorbic acid and total phenolic content and antioxidant activity of “jalapeño” (Veracruz, Mitla, Tam Mild, Jaloro, Sweet Jalapeño), “yellow wax” [(Hungarian Yellow, Long Hot Yellow, Gold Spike (hybrid)], “Chile” (New Mexico-6, Green Chile), “ancho” (San Luis Ancho), and “serrano” (Hidalgo) peppers were investigated at green or yellow stages of maturity. Major pepper flavonoids were quercetin and luteolin which were present in conjugate forms. Total flavonoid content varied from none detectable to 800 mg/kg after hydrolysis. “Chile”, “yellow wax” and “ancho” peppers had greater flavonoid and ascorbic acid contents and antioxidant activities than “jalapeño” peppers. Sep-Pak C₁₈(tm) bound phenolic compounds, including flavonoids, correlated well with antioxidant activity (r²=0.86). Luteolin had highest antioxidant activity followed by capsaicin and quercetin on equimolar basis.     

RELATIONSHIP OF USDA MARBLING GROUPS TO PALATABILITY OF COOKED BEEF

As marbling increased from“practically devoid” to“moderately abundant”, loin steaks were more palatable (P<0.05) about 2/3 of the time, round steaks were more palatable (P<0.05) about 1/8 of the time, and loin steaks were more likely to be assigned high (≥6.00) panel ratings and to have low (≤3.63 kg) shear values. However, increases in marbling from“slight” to“moderately abundant” (A maturity) and from“small” to“moderately abundant” (A+B maturity) had little or no efect on percentage incidence of loin or round steaks with panel ratings ≤2.99 or ≥4.00, or with shear values ≥6.35 kg or ≤4.99 kg. Differences in marbling explained about 33% (loin) and 7% (top round) of the variation in overall palatability ratings in A, B, C, and A+B maturity carcasses.     

Instrumental measurement of pomegranate texture during four maturity stages

Texture of pomegranate fruit and arils are the main quality attributes in the food process industries. In this study, the texture properties of pomegranate fruit and arils (cv. “Ashraf”) at four different stage of maturity (88, 109, 124, and 143 days after full bloom) were evaluated using the puncture test (rupture force and rupture energy) and compression test (bioyield force, rupture energy, and young modulus). The tests showed that all studied textural parameters were sensitive textural parameters for distinguishing the maturity stages. Rupture force and rupture energy of pomegranate fruit were determined at top, middle, and bottom positions of the fruit. The results showed that compression load values of aril increased with advances in maturity stage of fruit, while puncture load values of fruit decreased. The textural properties of pomegranate fruit and arils exhibited a strong dependence (p < .05) on the degree of maturity at harvesting time. Also results showed that rupture force of three different studied positions of fruit was severely different. The highest and lowest values were observed at top and middle position, respectively.     

Effect of water deficit on yield and protein content in pearl millet grains

Seventy-two pearl millet genotypes were water stressed at panicle development and grain filling stages. Neither grain yields, yield components, protein percent nor total protein per unit area were affected by water deficit during panicle development but protein content per grain was increased. When plants were water stressed during grain filling, grain yield, grains per unit area and 1000 grain weight were reduced, but grain protein percentage increased. Total protein per unit area was reduced primarily due to lower grain yield. The protein content per grain was unaffected by stress, suggesting that the apparent increase in protein percentage is due to reduced carbohydrate accumulation under stress.     

An Evaluation of Marinated Southern Peas (Vigna unguiculata)

Cooked southern peas (Vigna unguiculata) of two levels of maturities were soaked in sweet- or hot-flavored marinades. Marinade treatments and maturity level of the peas affected most attributes tested. Treated peas had less moisture, protein and nitrogen-free extract and more fat, crude fiber, ash and caloric content than unmarinated peas. Luminosity was reduced, redness was varied and yellowness was increased by marinating. Firmness of marinated peas was increased. PER was not affected and averaged 1.83. pH was lowered from 6.6 to 3.9; acidity was raised from 0.1% to 1.9%. Neither treatment nor maturity affected the microbiological counts. Samples were scored as “like slightly.”     

Anthocyanins,Antioxidative, and Antimicrobial Properties of American Cranberry (Vaccinium macrocarpon Ait.) and their Press Cakes

ABSTRACT: Amounts of total phenolics, anthocyanins, and ascorbic acid in 4 American cranberry varieties harvested at 4 stages of maturity were measured. The larger amount of phenolic compounds was found in berries of “Black Veil” cultivar (504 mg/100 g) at II stage of maturity. Significantly larger amounts of anthocyanins were determined in the overripe berries of the cultivars “Ben Lear” and “Black Veil.” The amount of ascorbic acid in berries increased during ripening from I to III stage, and slightly decreased in the overripe berries. The biggest quantities of ascorbic acid were found in the ripe berries of “Ben Lear” cultivar (15.8 mg/100 g). The distribution of anthocyanins pigments was determined by HPLC‐UV/MS in mature berries. The composition of individual anthocyanins in berries was quite similar in all the studied cranberry cultivars. While skins of cranberries are rich in anthocyanins and other phenolic compounds, the extracts of the by‐products of cranberries juice—berry cakes, were analyzed and obtained results were compared with the properties of extracts made from whole berries. The anthocyanins and total phenolics content, radical scavenging activity, antimicrobial activity of the whole berries, and their press cakes extracts were measured. All investigated extracts from berries and their press cakes showed good radical scavenging activity and revealed antimicrobial properties. It was found that Bacillus cereus (ATCC 10876) and Micrococcus luteus (ATCC 9341) were the most sensitive among 10 tested Gram‐negative and Gram‐positive bacteria.