Improve Oil Yield Research Articles

Effect of talc and water addition on olive oil quality and antioxidants

AbstractThe effect of using water and talc to improve oil yield was examined for the case of the Carrasqueña cultivar for the first time. The influence of these treatments to the antioxidant content (phenols and tocopherols) and quality parameters of the oil are discussed with regard to findings for Picual cultivar (a cultivar extensively studied in the past for various reasons) oils extracted and analyzed under the same conditions. Before the oil extraction the fruits from both cultivars were characterized for the ripening index, flesh/stone ratio, moisture, oil content, and instrumental color of fruits and crushed fruits. Water addition caused a decrease in oil yield and extractability, an increase in the peroxide index and a decrease in K270 and the total phenol content, whereas the instrumental color was scarcely affected. Talc addition resulted in an increase in oil yield and extractability, a decrease in the peroxide index and α‐tocopherol content and a marked effect on the instrumental color measurement. Results show that for both Carrasqueña and Picual cultivars (fruits with a ripening index of 5.14 and 4.92, and a moisture content of 53.0 and 56.2%, respectively) water addition at a 42.9% w/w is not advisable. Conversely, talc addition increases oil yield without affecting negatively the quality parameters, although it decreases α‐tocopherol content and has a marked effect on oil color.Practical applications: This paper shows the effect at a laboratory scale of adding talc and water to olive fruits from two different cultivars on oil yield, some quality parameters, tocopherol and phenol content and color. Results indicate that water addition to the paste during malaxation has important drawbacks such as a negative effect on some quality parameters which are relevant in the official olive oil grading (peroxide index and K270), and also in oil yield and phenol content. Conversely, talc addition has important advantages such as an increase in oil yield without affecting negatively the quality parameters, although it decreases α‐tocopherol content and affects oil color.

Application of microsatellite polymorphisms to study the diversity in seed oil content and fatty acid composition in Nigerian sesame (Sesamum indicum L.) accessions

Improving oil yield and a healthy fatty acid profile is a major breeding objective in sesame. In this study, the variability in simple sequence repeat motifs were used to study the diversity in 30 Nigerian sesame accessions in relation to the analyzed variation in oil content and fatty acid composition as a fundamental step towards its genetic improvement. Sesame seed oil content ranged from 40 to - 55 % (mean value of 47.65±2.82.8 %). Palmitic, stearic, oleic, linoleic and α-linolenic acid are the principal fatty acids with unsaturated/saturated fatty acid ratio of 5:1. Linoleic acid (45.65±1.151.15 %) and α-linolenic acid (0.3±0.040.04 %) were the most predominant and least fatty acids, respectively. High genetic variability was found among the accessions with the repeat motifs (TC12 - TC25) generated from two highly informative primer pairs clearly differentiating the 30 accessions into eight Groups. The seed oil yield and fatty acid composition shows that sesame oil is highly valuable for industrial purposes and assured human health. The variability in the accessions based on microsatellite markers was closely related to the variation in oil yield and fatty acid composition, which could be potentially beneficial in efforts towards marker assisted- selection for these traits. Key words: Microsatellite polymorphisms; Sesamepolymorphisms, sesame,; seed oil content,; fatty acid composition.

Discovery and use of single nucleotide polymorphic (SNP) markers in Jatropha curcas L.

Various programs for genetic improvement in oil yield of the biofuel plant Jatropha curcas L. are currently in progress worldwide. In order to develop strategies for genetic improvement, it is important to estimate the degree of diversity at the genetic level among various genotypes of J. curcas. High-throughput sequencing of complexity-reduced nuclear genomic DNA of J. curcas coupled with computational analysis discovered 2,482 informative single nucleotide polymorphisms (SNPs). Genotyping of selective SNPs among 148 global collections of J. curcas lines and further diversity analysis through NTSYS-pc, DARwin and Structure 2.0 software revealed that a narrow level of genetic diversity existed among the indigenous genotypes as compared to the exotic genotypes of J. curcas. The level of marker informativeness along with distance-based and Bayesian clustering revealed grouping of the accession from Togo (Africa) with various Indian accessions at K = 4 and K = 5 values (where K represents the number of populations). The diverse accessions identified in the study will be of further use in genetic improvement of J. curcas through quantitative trait loci and association mapping.

Responses of Seed Yield and Quality to Nitrogen Application Levels in Two Oilseed Rape (Brassica napus L.) Varieties Differing in Nitrogen Efficiency

The relationship between nitrogen efficiency (NE), defined as seed yield per unit nitrogen (N) application, and seed quality was examined in two oilseed rape (Brassica napus L.) varieties at 5 N application levels, 0.6, 3, 6, 12, 15 mmol L−1, N1, N2, N3, N4 and N5, respectively. Seed yield, oil yield and protein content were increased with the increase in N application level, but NE and oil content were decreased, and the fatty acid composition in seed was hardly changed. Analysis of seven fatty acids revealed aslight decrease in the contents of erucic acid and arachidonic acid with the increase in N application level, but no obvious change in the contents of palmitic acid, stearic acid, oleic acid, linoleic acid and linolenic acid. Compared with the low NE variety H29, the seed yield and contents of erucic acid and arachidonic acid in the high NE variety bin270 were more markedly increased with the increase in N application level, and the oil content was hardly changed. The seed yield, oilcontent and oil yield were higher in the high NE variety than in the low NE variety at all 5 N application levels. There were no significant differences in protein, palmitic acid, stearic acid and oleic acid contents between the varieties at any of the 5 N application levels, but there were slight differences in the linoleic acid and linolenic acid contents between the two varieties. In brief, N application improved oil yield more greatly in the high NE variety than in the low NE variety, but hardly affected the fatty acid composition. Therefore, the seed quality and oil content of oilseed rape may not be decreased by breeding of a high NE variety with a high N absorption efficiency and high N use efficiency.

English

To evaluate the relationship among seed and oil yield as well as determine the best indirect selection criteria for genetic improvement of seed and oil yield in canola a randomized complete block design with three replications was conducted using 17 cultivars. Step-wise regression of seed and oil yield revealed that 98.4 and 98.9% of total variation exists in these traits accounted for by the traits seed yield, oil percent, plant height and days to physiological maturity for oil yield while the traits biological yield, harvest index, days from planting to flowering initiation and no. grain/pod for seed yield . Path analysis for seed and oil yield designed high efficiency of the traits plant height and days to physiological maturity as indirect selection criteria for genetic improvement of oil yield and the traits biological yield and no. grain/pod for seed yield improvement in canola cultivars especially in early generations of breeding programs. Key words: Canola, correlation analysis, path analysis, indirect selection, selection criteria, genetic improvement.

KINETIC MODEL AND TECHNOLOGY OF ULTRASOUND EXTRACTION OF SAFFLOWER SEED OIL

ABSTRACTSafflower seed oil rich in linoleic acid is a kind of functional health oil. The effects of various parameters, such as solvents, liquid–solid ratio and extraction time, on both ultrasonic‐aided and conventional safflower seed oil extractions were investigated through experiments. The results indicated that n‐hexane was a better solvent for the two above‐mentioned extraction methods. Under the following conditions: temperature 35C, liquid–solid ratio 5, extraction time 30 min and ultrasound power 300 W, the oil extraction yield reached 27.02%. However, with the conventional safflower seed oil extraction method, it was only 25.00% when the technical parameters were: temperature 50C; liquid–solid ratio 6; extraction time 60 min. Obviously, the advantages of ultrasonic extraction were as follows: reducing extraction temperature; decreasing solvent quantity; saving time; and improving oil yield. In addition, on the basis of Fick's first law, the kinetic models of ultrasonic extraction and conventional extraction were compared and authenticated. The results showed that a close match was found between experimental data and kinetic equations, and the equations could better simulate safflower oil extraction process. This approach provided a theoretical background for the extraction of safflower seed oil.PRACTICAL APPLICATIONSIn this work, an efficient extraction method – ultrasound‐aided extraction method for safflower seed oil – was acquired. Compared with conventional extraction method, the advantages of ultrasonic extraction were: reducing extraction temperature, decreasing solvent quantity, saving time and improving oil yield. In addition, equipments used in ultrasound‐aided extraction and operation were simple and high efficiency. Therefore, this ultrasonic technology has a brilliant application prospect in extraction of safflower seed oil and other vegetable oils.

Lipid quality of the diatoms Skeletonema costatum and Navicula gregaria from the South Atlantic Coast (Argentina): evaluation of its suitability as biodiesel feedstock

Since the fatty acid ester profile of a given biofuel is relatively consistent with the source’s fatty acid profile, the properties of the biodiesel produced from a particular feedstock exhibit predictable quality. Thus, lipid fractions and the fatty acid composition of stationary growth-phase cultures of the local strains of the diatoms Skeletonema costatum and Navicula gregaria were analysed to evaluate their suitability as biodiesel feedstock. Total lipid content was 20.83 pg cell−1 in S. costatum and 19.17 pg cell−1 in N. gregaria. Neutral lipids were the main fraction of total lipids in both species, accounting for ca. 65% and 76%, respectively. S. costatum was predominant in saturated fatty acids (SFAs; 43.48 %) and monounsaturated fatty acids (MUFAs; 40.11%), while N. gregaria was predominant in MUFAs (54.85%), followed by SFAs (33.42%). In S. costatum, the main fatty acids in neutral lipid fraction were myristic, palmitic, palmitoleic and oleic acids, while the main ones in N. gregaria were palmitic and palmitoleic acids. The oils extracted from these species presented linolenic acid contents within biodiesel’s quality specifications. However, in neutral lipid fraction both species showed eicosapentaenoic acid levels higher than the required limit. The lipid quality analysed in both species suggests that a biodiesel derived from these oils may present an acceptable cetane number, but likely poor cold-flow properties. This baseline information is useful for future research tending to find more suitable conditions in order to improve oil yield. In addition, both estuarine species neither compete with agriculture for food nor require farmland nor fresh water.

Variability of yield determining components in winter rapeseed (Brassica napus L.) and their correlation with seed yield

Designing breeding programs for rapeseed (Brassica napus L.) cultivars with improved seed and oil yields require information about the genetic variability of traits effecting seed and oil production. This investigation was undertaken in order to examine phenotypic and genetic variability, broad-sense heritability, genetic gain under selection and interrelationships of some agronomic and seed quality traits of investigated genotypes. Genotypes, years and their interaction showed significant variation for all studied characters. Phenotypic variability coefficients were higher than genetic ones. Broad-sense heritability estimates ranged from 12.66% (for ripening period) up to 52.12% (for days to first pods filling). Expected genetic gain was lowest for days to maturity (0.45%) and highest for height to the first lateral branch (12.94%). The analysis of genetic correlations revealed that seed yield per plant is highly and positively associated with pods per plant, oil content, plant height and ripening period, although significant negative correlations were found between seed yield per plant and leaves per plant, days to maturity, protein content, days to first pods filling, days to flowering, height of the first lateral branch and 1000 seed weight. Genetic path-coefficient analysis indicated that pods per plant and oil content were the most important components of seed yield per plant. Their direct effects on seed yield per plant were p=0.472 and p=0.082, respectively. Protein content had highly significant negative direct effect on seed yield (p=-0.365), followed by 1000 seed weight (p=-0.017) and height to the first lateral branch (p=-0.081). These observations will support the selection of genotypes with desired traits for further rapeseed seed and oil yield improvement.

Factors that modify early and late reproductive phases in oilseed rape ( Brassica napus L.): Its impact on seed yield and oil content

Oilseed rape yield potential could be improved lengthening the duration of the late reproductive phase by increasing the number of grains per unit area. Photoperiod sensitivity could be used as a tool to manipulate the reproductive phase and thereby the number of grains. The aim of this study was to assess (i) the effects of different combinations of photoperiod on the duration of different phases and (ii) analyze how the changes in that duration affect yield (and its components) as well as oil seed content in oilseed rape. Field experiments were conducted in a factorial combination of three cultivars and three photoperiod regimes: natural photoperiod (NP) which represents the control and extended photoperiod of 6 h over NP (NP + 6) during emergence (E)–flower buds visible (FBV) and FBV–maturity (M) arranged in a randomized complete block design with three replicates, during two years representing three environments. Results showed that oilseed rape evidenced photoperiod responses during vegetative and early reproductive phases. Due to the lack of correlation between the duration of the vegetative and reproductive phases, it is possible to speculate the vegetative period may be altered independently of the modification of the rest of the phases. The positive relationship between grain number per m 2 and the duration of the late reproductive phase suggests that yield could be increased by lengthening the duration of that phase. Thus, regardless of the effect on the previous phase, the photoperiod sensitivity found in the early reproductive phase opens the possibility to manipulate the relative durations of vegetative and reproductive phases. Therefore, the length of the reproductive phase will be increased at the expense of a reduction in the duration of the vegetative phase, but without changing the whole duration of the crop cycle. This strategy could increase yield in oilseed rape in the future. Variations in yield were mostly explained by changes in the grain number per unit area without significant correlation with grain weight. However, a negative relationship between grain weight and grain number was found, showing a slight counterbalance in yield, by decreasing the grain weight. Since oil concentration appeared to be a more conservative attribute, increases in crop yield through a higher grain number per unit area would be a suitable strategy for improving oil yield as no reductions in oil concentration can be expected.

Optimization of the Abencor system to extract olive oil from irrigated orchards

AbstractStudying the composition of olive oil requires cold‐press olive oil extraction. One of the most common laboratorial mills is the Abencor system. However, its operation protocol was formulated decades ago for Spanish olive varieties from traditionally rain‐fed orchards. We modified this protocol for use with “Barnea” and “Picual” olives from irrigated orchards that are characterized by high water content. Independent effects of malaxation time, temperature, water addition and talc addition on extraction efficiency, and major quality indices of virgin olive oil were studied. Overall, addition of talc to the fruit paste was the most significant treatment in terms of yield and quality of the oil although its effect was cultivar dependent. Improved oil yield was particularly significant for “Picual.” Extended malaxation time was also effective in improving oil extractability. Addition of talc generally improved oil‐quality parameters, while water addition had the opposite effect. Yet, quality parameters remained within the extra virgin level. Temperature increments reduced oil quality. The need to adapt a modified protocol for use with fruits from irrigated orchards that will facilitate critical comparison of results obtained from different agronomic theses and different laboratories is highlighted. It is recommended that each laboratory develops an appropriate protocol for the operation of the Abencor system in accordance to the characteristics of the olive fruit they are working with.Practical applications: Abencor system serves as the major laboratorial mill world‐wide. Those mills allow the researchers to characterize olive oil in accordance to the treatments received by the trees. This cannot be done in commercial mills. The system operation protocol was established decades ago for fruits from rain‐fed orchards. In the past decade there was a rapid increase in the use of irrigation in olive orchards and therefore it is crucial to optimize the operation protocol for fruit with relatively high water content. In the current work we have evaluated the influence of a series of technological parameters (i.e., talc and water addition, malaxation time, and temperature) on the extraction efficiency and quality indices of olive oil. This allowed us to present a modified protocol for the Abencor system operation suitable for olive fruit of irrigated orchards that will facilitate a reliable representation of the influence of different treatments on the yield and characteristics of the olive oil.

Hydrothermal pyrolysis of swine manure to bio-oil: Effects of operating parameters on products yield and characterization of bio-oil

Advanced hydrothermal pyrolysis technology was used to process swine manure for waste reduction and energy production. The effect of operating parameters on products yield was investigated to determine the optimal condition for the process. Operating temperature, retention time, and the initial pressure of process gas were all found to affect oil yield. Increasing the temperature from 260 °C to 340 °C was found to increase the oil yield from 14.9% to 24.2%. Retention time affected the completeness of the hydrothermal liquefaction process. The hydrothermal pyrolysis of swine manure was completed within 15 min. Increasing the initial nitrogen pressure by a specific amount improved oil yield. The results of this study showed that the optimal conditions of operating parameters were: 340 °C; retention time of 15 min, and initial process gas pressure of 100 psi. The composition of the oil product was also analyzed by GC–MS, FTIR spectroscopic, and elemental analysis techniques. The elemental analysis showed that bio-oil could be a potential source of synthetic fuels and chemical feedstock.

Hydrogenation of heavy liquids from a direct coal liquefaction residue for improved oil yield

For hydrogenation of heavy liquids in direct coal liquefaction residue (DCLR) within the direct coal liquefaction (DCL) process, heavy liquids in a DCLR derived from a bench-scale Shenhua DCL process using Shenhua coal are evaluated under two conditions. One simulates the coal liquefaction conditions of the Shenhua plant in the presence of a Fe-based Shenhua catalyst; the other one simulates the online hydrotreating conditions in the presence of a NiMo/Al 2O 3 catalyst. The results show that the heavy liquids of DCLR can be hydrogenated under these two conditions yielding less heavy products; hydrogenating the heavy liquids under the online hydrotreating conditions is more effective than that under the coal liquefaction conditions; the preasphaltene fraction is a main problem that yields non-soluble materials under these hydrogenation conditions. The results suggest that hydrogenation of toluene soluble and tetrahydrofuran soluble fractions of the DCLR under the coal liquefaction and online hydrotreating conditions is feasible, but their conversion to lighter products are inapparent under the coal liquefaction conditions, and elimination of the formation of tetrahydrofuran insoluble fraction in the online hydrotreator should be considered.

Influencia de diferentes coadyuvantes tecnológicos en la calidad y rendimiento del aceite de oliva virgen utilizando la metodología de superficies de respuesta

Response surface methodology was employed to evaluate the effects of two technological co-adjuvants in virgin olive oil extraction from the Hojiblanca olive variety with a low ripening index: the addition of talc during the malaxation of the olive paste step, water addition during the same step and olive paste storage over a small period of time. Ranges of operation were established as follows: talc addition, 0-2 % (w/w); water addition, 0-20 % (w/w); and storage time, 0-36 h. Mathematical models and statistical analyses (ANOVA) were performed in order to evaluate the effects of theses factors on oil yield and quality of olive oils obtained. Using a confidence level of 95 %, oil yield, acidity, peroxide index, K270 and Chlorophyll contents, models are significant. The addition of talc is more effective in improving oil yield and paste storage is also useful to improve oil yield although a loss of oil quality is observed; but all the olive oil obtained may be characterized as extra virgin olive oil according to the regulations of the European Union.

Association pattern among the yield attributes in varieties and hybrids of sunflower (Helianthus annuus L.)

SUMMARY Three varieties, CO 4, Morden and TNHSF 239 (a pre-release culture) and two hybrids, TCSH 1 and KBSH 44, were selected for this study. Simple correlation coefficients were estimated among characters for individual varieties and hybrids. Two traits, seed yield and 100-seed weight, are important selection indices for oil yield improvement in both varieties and hybrids. Head weight can be considered as a selection index for improvement of seed and oil yield in hybrids only. Likewise, oil content is an important selection index for oil yield improvement in varieties. It can also be inferred that the results obtained from the association analysis of pooled data for varieties and hybrids will give ambiguous results and have a negative impact on the yield improvement program. Thus it is desirable to compute separate association analyses for each variety and hybrid to identify effective selection indices for the improvement of sunflower. RESUMEN Se seleccionaron para este estudio tres variedades llamadas CO 4, Morden, TNHSF 239 (variedad precomercial) y dos híbridos TCSH 1 y KBSH 44. Se estimaron coeficientes de correlación simples entre caracteres para cada variedad e híbrido separadamente. Los atributos rendimiento de semilla y peso de 100 semillas son importantes índices de selección para el mejoramiento del rendimiento de aceite tanto para variedades como híbridos. El peso del tálamo puede considerarse un índice de selección para el mejoramiento del rendimiento en semilla y aceite sólo en el caso de los híbridos. De manera similar, el contenido de aceite es un índice de selección importante para la mejora del rendimiento de aceite sólo en el caso de las variedades. Puede también inferirse que los resultados obtenidos de los análisis de asociación de datos en variedades e híbridos analizados en conjunto producirán resultados ambiguos y tendrían un impacto adverso en un programa de mejoramiento por rendimiento. Por lo tanto, siempre es deseable conducir análisis de asociación separados para cada variedad o híbrido para identificar índices de selección para el mejoramiento de girasol. RÉSUMÉ Les trois variétés CO 4, Morden, TNHSF 239 (cultivar experimental) et les deux hybrides TCSH 1 et KBSH 44 ont été sélectionnés pour cette étude. Les coefficients de corrélation simple entre caractères ont été estimés séparément pour chaque variété ou hybride. La production de grains et le poids de 100 grains sont des indices de sélection importants pour l’amélioration du rendement en huile pour les variéts comme pour les hybrides. Le poids du capitule peut être considéré comme un index de sélection important pour le rendement en grain et en huile seulement pour les hybrides. De la même façon, la teneur en huile est un index de sélection important pour l’amélioration du rendement en huile seulement pour les variétés. Il peut également être inféré que les résultats obtenus en agrégeant les données des variétés et des hybrides aurait conduit à des conclusions ambiguës et aurait eu des effets néfastes sur le programme d’amélioration de la productivité. Ainsi il apparaît souhaitable, pour identifier des index de sélection pour l’amélioration du tournesol, de calculer séparément les corrélations entre caractères pour chaque variété et hybride.

Improvement of oil yield and its distribution from coal extraction using sulfide catalysts

Abstract Extraction of Mae Moh lignite using toluene–tetralin mixture was performed in a batch reactor at a temperature range from 370 to 490 °C and under initial hydrogen pressure up to 12 MPa. Experiments were carried out to investigate the effects of temperature and initial hydrogen pressure on coal conversion, liquid yield and liquid composition. The effect of catalysts Fe2S3, Fe/Ni and Ni/Mo impregnated into activated carbon was also studied. In the absence of a catalyst, the oil yield decreased with temperature above 410 °C and the content of naphtha and kerosene increased while light gas oil and gas oil decreased with increasing temperature. The presence of catalyst would benefit the formation of lighter components, kerosene and light gas oil. Extraction in the presence of Ni/Mo catalyst, the liquid yield reached 64.6 wt% (daf) which included naphtha 2%, kerosene 72.8%, light gas oil 14.9%, gas oil 2.4% and long residue 7.9%. For GC–MS analysis, the fraction of kerosene was composed of tetralin, naphthalene, dodecamethyl-cycloheptasiloxane, methyl dodecanoate, tetradecamethyl-cycloheptasiloxane, ethyl dodecanoate, methyl tetradecanoate and dibutyl phthalate.

Qualitative and Quantitative Evolution of Selected Oil Palm Seed Production at La Dibamba Specialised Centre on Oil Palm Research (Cameroon)

The La Dibamba Specialised Centre on Oil Palm Research (CEREPAH) is a member of CIRAD’s “network” that includes CNRA La Mé (Côte d’Ivoire), Embrapa Rio Urubu Station (Brazil), SRPH Pobè Station (Benin), P T Socfindo (Indonesia) and CIRAD (France). Sustainable high yielding oil palm breeding is based on a recurrent selection scheme (RRS). The major advantage is the capacity to produce new planting materials as soon as the value of the crosses or the parents tested obtained from progeny tests is known. At the end of the first cycle, 18 per cent improvement in oil yield was achieved. An average yield increase of 36 per cent was achieved over two cycles of recurrent reciprocal selection. At La Dibamba the production of first selection cycle planting materials started in 1985, while that of the second in 1991 which progressively took over the first selection cycle planting materials. Since 2003, 98 per cent of seeds produced are of the second selection cycle. The number of dura parents, the potential number of pisifera parents and the seed production potential are high. The gap existing between the seed production potential and the quantity of seeds produced yearly is explained. Keywords: Oil palm, seed production, dura parent, pisifera parent, category, potential, La Dibamba.

Changes in agronomic traits of sunflower hybrids over 20 years of breeding in central Argentina

This paper applies linear mixed model and pattern analyses to 122 on-farm trials of commercial and near-commercial sunflower ( Helianthus annuus L.) hybrids grown over 15 years in 32 locations of central Argentina to determine the contributions of change in characteristics of germplasm pools to increases in oil yield. The ‘Relative Peak Performance’ (best linear unbiased predictors, BLUPs) of 49 hybrids released for the conventional market between 1983 and 2005 showed genetic gains of 11.9 kg ha −1 year −1, 0.19% year −1 and 16.1 kg ha −1 year −1 for oil yield, grain-oil concentration and grain yield, respectively. Oil yield improvement was consistent across three market segments and a biplot of genotype-by-attribute BLUPs summarised 20 years of breeding to demonstrate how the merging of two germplasm pools of differing maturity, achene type and grain-oil concentration resulted in step-wise improvements in grain yield and grain-oil concentration and a move toward an intermediate maturity. The analysis of general combining ability within a breeding program shows that the female and male germplasm pools were improved in different ways over time. On the female side, much of this improvement was to encompass different combinations of the determining traits of oil yield, while on the male side the improvement was more linear in terms of exploitation of genotypic variance for oil yield per se.

Characteristics of hemp ( Cannabis sativa L.) seed oil

Characteristics of oil extracted from hempseeds subjected to microwave treatments were evaluated. Microwave treatment improved oil yield, increased carotenoid and other pigment contents and decreased p-anisidine value without significant changes in other properties. Hempseed oil showed absorbance in the UV-B and UV-C ranges with potential for use as a broad spectrum UV protectant. b-Tocopherol concentrations increased, while the major tocopherol, g-tocopherol, and fattyacid composition of the oil were unaffected bymicrowave treatment of hempseed. Hempseed oil showed high kinetic stabilityduring heating and cooling, as characterized bydifferential scanning calorimetry(DSC). Microwave treatment shifted the melting range of oils to lower temperatures and increased oxidation temperatures, suggesting increased protective effect upon heating. Crown Copyright # 2001 Published byElsevier Science Ltd. All rights reserved.

Genetic improvement of sunflower in Argentina between 1930 and 1995: Part III. Dry matter partitioning and grain composition

We compared the partitioning of dry matter and the oil and protein content in the grain of sunflower ( Helianthus annuus L.) cultivars released in Argentina between 1930 and 1995. At anthesis, the fraction of plant dry matter partitioned to leaf and head increased, whereas the fraction in the stem decreased with year of cultivar release. Improved oil yield was related to the increase in: (i) harvest index (grain mass/shoot mass) from about 0.3 to 0.5; (ii) kernel-to-grain ratio from 0.6 to 0.8; and (iii) kernel oil concentration from 58 to 70%. The duration of the period of grain growth as a fraction of season length accounted for half of the variation in harvest index. Kernel oil concentration was negatively associated with protein concentration which dropped from 23 to 13%. Further improvement in partitioning may be possible, including increase in harvest index resulting from enhanced contribution of stored assimilate to grain growth. Owing to the dramatic improvement in partitioning achieved in the last seven decades, however, further increase in yield may need to focus on increasing biomass production.

Liquefaction Reactivity of Methylated Illinois No. 6 Coal

The reactivity of O-methylated and reductively methylated coals were tested for noncatalytic liquefaction reactions in tetralin solvent at 693 and 723 K to evaluate the effect of methylation on the conversion of Illinois No. 6 coal. For the liquefaction test at 693 K, the oil yield from reductively methylated coal drastically increased from 37 to 60 wt % compared with the raw coal. On the other hand, the oil yield of O-methylated coal was approximately 50 wt %. The improvement of oil yield for methylated coals was related to the number of methyl groups introduced by methylation. The increased oil yield for methylated coals was due to the acceleration of the decomposition reaction for preasphaltene. The difference in oil yield between raw and methylated coals decreased with increasing reaction temperature to 723 K, but an improvement of oil yield was observed. These results indicated that the methylation of coal molecules was effective for the production of the oil fraction, especially under lower severity conditions.