Concentration Of Sunflower Oil Research Articles

Differential Impact of the Biodegradation Sunflower Oil, Particulate Substrate, Caused by the Presence of Saccharose, Soluble Substrate, on Activated Sludge Treatment

This research studies the biodegradation of sunflower-type vegetative oil in two proposed activated sludge systems, the first one to biologically treat an influent containing only vegetative oil and the second one to treat a mixture of vegetable oil plus saccharose. The purpose of these analyses is to evaluate the differential impact caused by the soluble substrate saccharose on the removal of vegetative oil. Vegetative oil biodegradation in both systems was studied and quantified via integral mass balance, and relevant operating parameters were monitored. This experimentation based on the mass balance estimation of biodegraded vegetative oil serves as a reference to understand the effect of soluble substrates present in mixed wastewater on oil biodegradation. Information was generated on the performance of the two activated sludge treatment systems. Both influents were pre-stirred before they entered the bench-scale activated sludge plants. The working range for sunflower oil concentration was 120 to 520 mg/L for the influent with sunflower oil and 180 to 750 mg/L for the influent with sunflower oil and saccharose. Biodegradation was in the order of 56 to 72% and 47 to 67%, respectively. The removal of sunflower oil in biodegradation and flotation was in the order of 90% in both scenarios.

Optimization of vitamin B12 nano-emulsification and encapsulation using spontaneous emulsification.

In this study, the use of low-energy methods for nanoemulsification of vitamin B12 was investigated to protect this bioactive substance. The effects of sunflower oil concentrations (4-8%), Tween 80 (8-16%), and vitamin B12 (5-15%) on the physicochemical properties of B12 nanoemulsion were evaluated using response surface methodology (RSM). The results indicated that the quadratic model was the most fitting model for experimental data. Optimization revealed that the optimal formulation contained 6.5% sunflower oil, 9.6% Tween 80, and 13% vitamin B12, resulting in maximum efficiency, viscosity, and vitamin B12 content, as well as minimum pH, turbidity, p-Anisidine index, particle size, and polydispersity index (PDI). Under optimal conditions, pH, viscosity, turbidity, efficiency, vitamin B12, p-Anisidine index, PDI, and particle size were 7.24, 17.0024 cp, 2.19, 51.98%, 5.54ppm, 0.01, 0.34, and 322nm, respectively. This study highlights the effectiveness of spontaneous emulsification as a carrier for the encapsulation of bioactive compounds.

The Impact of Climatic Conditions on Oil Content and Quality, in Sunflower

Sunflower (Helianthus annuus L.) crop is grown worldwide, under a range of agro-environments. This crop is primarily grown for its edible oil but also for its achenes (confectionery types), both commonly used in human food. With ongoing climate change, sunflower, as a spring crop, could be more exposed to the direct effect of heat stress and to different drought scenarios, resulting in severe yield losses, oil content decrease and alteration of fatty acids composition. The oil concentration in sunflower (whether linoleic or oleic varieties) is valued above the contribution of genotype, of environment but also of the crop management. In our study, with different sunflower hybrids, experimented in different conditions of the environment, we obtained results on oil content and fatty acids composition. The oil content in kernels is influenced by climate. This depends by air temperature in period of anthesis or during grain filing, also by rainfall. The unsaturated fatty acids of sunflower oil are much more affected by genotype and environment than the saturated ones. Cooler regions offer a more favorable climate for the oil and linoleic acid synthesis. There is an indirect relationship for oleic and linoleic content, in sunflower oil.

Emulsification of Rosemary and Oregano Aqueous Extracts and Their In Vitro Bioavailability.

Due to their richness in phenolic compounds, Mediterranean plants such as rosemary and oregano are increasingly recommended for consumption for their numerous health benefits. The pH shift and the presence of digestive enzymes significantly reduce the bioavailability of these biochemicals as they pass through the gastrointestinal tract. To prevent this degradation of phenolic compounds, methods such as emulsification of plant aqueous extracts are used. The aim of this study was to investigate the effects of emulsification conditions on the chemical properties (total polyphenolic content and antioxidant activity) of emulsified rosemary and oregano extracts. Response surface methodology was applied to optimize sunflower oil concentration, rotational speed, and emulsifier concentration (commercial pea protein). The emulsions prepared under optimal conditions were then used in bioavailability studies (in vitro digestion). The antioxidant activity of the emulsified rosemary/oregano extracts, measured by the DPPH method, remained largely stable when simulating in vitro digestion. Analysis of antioxidant activity after in vitro simulation of the gastrointestinal system revealed a higher degree of maintenance (up to 76%) for emulsified plant extracts compared to aqueous plant extracts. This article contributes to our understanding of how plant extracts are prepared to preserve their biological activity and their application in the food industry.

Formulation of edible films based on carboxymethyl cellulose, cassava starch, and alginate using high‐intensity ultrasound emulsification treatments

Biopolymer-based edible films and coatings are useful for preserving the quality of minimally processed vegetables. Although its use is economical and respectful to the environment, its effectiveness depends on the final formulation and technological conditions applied. In this work, films based on carboxymethyl cellulose (CMC, 1.0%), cassava starch (CS, 3.0%), and alginate (ALG, 2.0%) using glycerol (Gly) as a plasticizer (30, 20, and 40% polymer, respectively) were formulated as control systems. In order to evaluate the application of high-intensity ultrasound (5 min and 40% amplitude power) during several emulsification treatments (sunflower oil concentrations range: 0.15–0.35%), the barrier, mechanical and optical properties, and the microstructure of the final films (ECMC, ECS, and EALG) were assessed. Ultrasound nanoemulsification treatment led to improved barrier properties only for CS-based films. Moreover, ECS film showed undetectable color changes, homogeneous, and stable nanoemulsions with the highest hydrophobic behavior that makes it suitable for coating fruits and vegetables. Novelty impact statement Ultrasound nanoemulsified films were formulated from different biopolymers bases. Formulations based on the cassava starch result in homogeneous and stable nanoemulsions. The results obtained are promising in order to formulate low-cost coating materials.

3D printing of kappa-carrageenan emulsion gels

The interest in personalised food through 3D printing has led to an increased interest in the formulation and production of more complex foodstuffs rather than simple water-based systems. 3% w/w Kappa-carrageenan (кC) emulsion gels were created containing 5–40% w/w sunflower oil (SFO); using two different emulsifiers, Tween 20 (T20) and Whey protein isolate (WPI). Differential scanning calorimetry showed that both T20 and WPI stabilised emulsions had only minor effects on the gelling and melting enthalpies of the кC, and had the same gelling temperatures. All tested formulations were printable under the same printing parameters, provided the feed rate was increased with SFO concentration. Confocal microscopy showed the presence of layering throughout the printed gels and that T20-stabilised emulsion gels had flocculated. Texture profile analysis was used to compare printed and cast 20 × 20 × 9.6 mm cuboids. For cast cuboids, as the SFO concentration increased, the hardness values decreased from 75 N ± 4 N to 18 N ± 1.5 N. For printed cuboids the hardness values were constant at 13 N ± 2 N. Upon compression, printed cuboids delaminated at the areas between the printed layers. Oscillatory rheology showed that cast gels were more resistant to shear strain compared to the printed gels and this was again believed to occur due to delamination between the semi-fused printed layers. This work demonstrates that кC emulsion gels can be 3D printed without a change in their physical performance regardless of SFO concentration up to 40%.

Stability of sunflower and rapeseed oil-in-water emulsions supplemented with ethanol-treated rapeseed meal protein isolate.

A protein isolate (ERPI) was prepared from ethanol-treated rapeseed meal and used as a stabilizing agent in sunflower and rapeseed oil-in-water emulsions. The aim of the current study was to explore the influence of protein and oil concentrations on initial stability of sunflower and rapeseed oil-in-water emulsions by evaluating Gibbs free energy (ΔG) and particle size distribution. The 7-day dynamics of emulsion stability was investigated by turbidity measurement as well. A 32 factorial design was applied to assess the significance of oil (5%, 10% and 15% w/w) and ERPI protein (0.25%, 0.5% and 1.0% w/w) addition on stability of the emulsions. The results demonstrated that the increase of oil concentrations from 5 to 15% positively influenced the initial stability of sunflower and rapeseed oil-in-water emulsions. In both oil types, ERPI protein supplementation at all levels resulted in significant differences in the stability of 5% and 10% oil emulsions but did not alter the initial stability of the emulsions prepared with either 15% sunflower or rapeseed oil. With a few exceptions, there was a good agreement between Gibbs free energy data and microstructural profiles of the emulsions. Overall, emulsions with all sunflower oil concentrations and 1.0% ERPI protein exhibited better initial and a 7-day stability dynamics compared to all rapeseed oil-based emulsions. The study demonstrated the potential of ethanol-treated rapeseed meal protein isolate to serve as an emulsifying agent in sunflower and rapeseed oil containing emulsions.

Ultrasonic-Assisted Fabrication of Concentrated Triglyceride Nanoemulsions and Nanogels.

In many food products such as gels, pastes, jellies, creams, sausages, and selected dressings or spreads, it is desirable to formulate concentrated triglyceride nanoemulsions so as to deliver lipophilic functional agents. In this study, the ability of ultrasonication to form nanoemulsions and nanogels containing high concentration of sunflower oil was investigated in the presence of sodium dodecyl sulfate (SDS) as a surfactant. The influence of SDS and oil concentration and duration of sonication on the physical stability, mean droplet diameter, and rheological properties of emulsions were determined. Ultrasonication for up to 9 min was highly effective on fabrication of stable nanoemulsions (an average droplet size of 158-171 nm) at low oil/surfactant ratio (10:0.7). The viscosity and storage modulus increased with decreasing the droplet size particularly at higher oil concentrations. The viscous nanoemulsions (containing 60, 50, and 40 wt % oil) transformed into viscoelastic gels when sonicated for 3, 9, and 30 min, respectively. On the basis of the findings of the present study, such textural and rheological modifications, resulted from droplet size decreasing, could be potentially useful in designing reduced fat gel-like products.

Validation of Fluorescence Spectroscopy to Detect Adulteration of Edible Oil in Extra Virgin Olive Oil (EVOO) by Applying Chemometrics.

Due to high price and nutritional values of extra virgin olive oil (EVOO), it is vulnerable to adulteration internationally. Refined oil or other vegetable oils are commonly blended with EVOO and to unmask such fraud, quick, and reliable technique needs to be standardized and developed. Therefore, in this study, adulteration of edible oil (sunflower oil) is made with pure EVOO and analyzed using fluorescence spectroscopy (excitation wavelength at 350 nm) in conjunction with principal component analysis (PCA) and partial least squares (PLS) regression. Fluorescent spectra contain fingerprints of chlorophyll and carotenoids that are characteristics of EVOO and differentiated it from sunflower oil. A broad intense hump corresponding to conjugated hydroperoxides is seen in sunflower oil in the range of 441-489 nm with the maximum at 469 nm whereas pure EVOO has low intensity doublet peaks in this region at 441 nm and 469 nm. Visible changes in spectra are observed in adulterated EVOO by increasing the concentration of sunflower oil, with an increase in doublet peak and correspondingly decrease in chlorophyll peak intensity. Principal component analysis showed a distinct clustering of adulterated samples of different concentrations. Subsequently, the PLS regression model was best fitted over the complete data set on the basis of coefficient of determination (R2), standard error of calibration (SEC), and standard error of prediction (SEP) of values 0.99, 0.617, and 0.623 respectively. In addition to adulterant, test samples and imported commercial brands of EVOO were also used for prediction and validation of the models. Fluorescence spectroscopy combined with chemometrics showed its robustness to identify and quantify the specified adulterant in pure EVOO.

English

The present study evaluated the impact of varying dietary linseed oil composition on growth, survival and tissue polyunsaturated fatty acids (PUFA) profiles in Nile tilapia (Oreochromis niloticus). Five iso-nitrogenious diets with varying linseed and sunflower oil concentrations were formulated and fish fed twice daily to for 3 months. Commercial diet was used as a control in triplicate tanks set for each diet treatment. Growth parameters were measured from changes in body weight and length. A 75:25 ratio of sunflower oil to linseed oil gave a better survival and specific growth rate than 100% linseed oil or 100% sunflower oil. Tissue PUFA composition were determined using gas chromatography. High dietary linseed oil composition (100%) resulted into significantly high (P<0.05) total n3 fatty acids (9.9-25%) and DHA (1.8-7.9%) in muscles whereas liver n3 fatty acids and DHA composition ranged between 9.3-25.5 and 0.7-2.6%, respectively. Muscle and liver n3/n6 ratio ranged between 0.7-2.2 and 0.7-2.6 while tissue arachidonic acid (ARA 20.4 n6) content ranged between 2.6-3.5% in muscles and 3.4-4.5% in the liver. ARA 20.4 n6 values were low relative to the dietary precursor, linoleic acid, LA, 18.2 n6.  Fatty acid deposition in the tissues increased with the feeding period with the third feeding month recording significantly higher DHA, total n3 and n3/n6 ratio. Based on the result, dietary linseed oil > 50% reduced growth and survival rate in tilapia, however, it increased tissue accumulation of essential fatty acids which also increased with the length of feeding period.   Key words: Growth, Tilapia, n3 fatty acids, linseed oil, polyunsaturated fatty acids (PUFA).

Alginate/Shellac beads developed by external gelation as a highly efficient model system for oil encapsulation with intestinal delivery

The aim of this study was to evaluate the potential of the alginate/shellac combination as wall material (WM) to develop an oil encapsulation system by external gelation. The Taguchi method, a powerful process optimization tool, was used to determine the optimal process conditions in which to prepare beads with a high oil encapsulation efficiency (EE). The effect of the variables: sunflower oil concentration in the emulsion (E[oil]: 30 and 50 %w/w), emulsion/wall material ratio (E/WM: 80/20 and 20/80 %v/v) and concentration of calcium chloride (CaCl2: 5 and 15 g/L) on the EE were evaluated. The bead morphology, the total oil content of beads (OCB), mean particle size, sphericity factor (SF) and swelling degree (Sw) were also investigated. Finally, the optimal alginate/shellac beads were submitted to in vitro digestion. The results showed that the beads formed under optimal conditions reached an EE value of 98.7% and OCB of 38.6%. The oil concentration in the emulsion was the variable that most affected the oil EE. The beads obtained were semi-spherical, smooth-surfaced, non-aggregated, with a particle size of 2.13 mm and SF of 0.08. The Sw of the developed alginate/shellac beads was unaffected at acid pH values; however, beads showed swelling under basic conditions (pH 7). The optimal beads showed more oil released during intestinal digestion than during gastric digestion. These findings have important implications for oil encapsulation and the design of delivery systems of oil soluble compounds, which are useful in the food industry for developing novel products containing health-promoting bioactive compounds.

Analysis and modelling of the factors controlling seed oil concentration in sunflower: a review

Sunflower appears as a potentially highly competitive crop, thanks to the diversification of its market and the richness of its oil. However, seed oil concentration (OC) – a commercial criterion for crushing industry – is subjected to genotypic and environmental effects that make it sometimes hardly predictable. It is assumed that more understanding of oil physiology combined with the use of crop models should permit to improve prediction and management of grain quality for various end-users. Main effects of temperature, water, nitrogen, plant density and fungal diseases were reviewed in this paper. Current generic and specific crop models which simulate oil concentration were found to be empirical and to lack of proper evaluation processes. Recently two modeling approaches integrating ecophysiological knowledge were developed by Andrianasolo (2014, Statistical and dynamic modelling of sunflower (Helianthus annuus L.) grain composition as a function of agronomic and environmental factors, Ph.D. Thesis, INP Toulouse): (i) a statistical approach relating OC to a range of explanatory variables (potential OC, temperature, water and nitrogen stress indices, intercepted radiation, plant density) which resulted in prediction quality from 1.9 to 2.5 oil points depending on the nature of the models; (ii) a dynamic approach, based on “source-sink” relationships involving leaves, stems, receptacles (as sources) and hulls, proteins and oil (as sinks) and using priority rules for carbon and nitrogen allocation. The latter model reproduced dynamic patterns of all source and sink components faithfully, but tended to overestimate OC. A better description of photosynthesis and nitrogen uptake, as well as genotypic parameters is expected to improve its performance.

Response surface methodology: optimisation of antifungal bioemulsifier from novel Bacillus thuringiensis.

An antifungal bioemulsifier compound was produced from a novel strain of Bacillus thuringiensis pak2310. To accentuate the production and as the first step to improve the yield, a central composite design (CCD) was used to study the effect of various factors like minimal salts (1X and 3X), glycerol concentration (2% and 4%), beef extract concentration (1% and 3%), and sunflower oil concentration (2% and 4%) on the production of bioemulsifier molecule and to optimize the conditions to increase the production. The E 24 emulsification index was used as the response variable as the increase in surfactant production was seen to be proportional to increased emulsification. A quadratic equation was employed to express the response variable in terms of the independent variables. Statistical tools like student's t-test, F-test, and ANOVA were employed to identify the important factors and to test the adequacy of the model. Under optimum conditions (1X concentration of minimal salts (MS), 2.6% glycerol (v/v), 1% beef extract (w/v), and 2% sunflower oil (v/v)) a 65% increase in yield was produced.

Prediction of sunflower grain oil concentration as a function of variety, crop management and environment using statistical models

Sunflower (Helianthus annuus L.) raises as a competitive oilseed crop in the current environmentally friendly context. To help targeting adequate management strategies, we explored statistical models as tools to understand and predict sunflower oil concentration. A trials database was built upon experiments carried out on a total of 61 varieties over the 2000–2011 period, grown in different locations in France under contrasting management conditions (nitrogen fertilization, water regime, plant density). 25 literature-based predictors of seed oil concentration were used to build 3 statistical models (multiple linear regression, generalized additive model (GAM), regression tree (RT)) and compared to the reference simple one of Pereyra-Irujo and Aguirrezábal (2007) based on 3 variables. Performance of models was assessed by means of statistical indicators, including root mean squared error of prediction (RMSEP) and model efficiency (EF). GAM-based model performed best (RMSEP=1.95%; EF=0.71) while the simple model led to poor results in our database (RMSEP=3.33%; EF=0.09). We computed hierarchical contribution of predictors in each model by means of R2 and concluded to the leading determination of potential oil concentration (OC), followed by post-flowering canopy functioning indicators (LAD2 and MRUE2), plant nitrogen and water status and high temperatures effect. Diagnosis of error in the 4 statistical models and their domains of applicability are discussed. An improved statistical model (GAM-based) was proposed for sunflower oil prediction on a large panel of genotypes grown in contrasting environments.

Rhamnolipid and lipase production by Pseudomonas aeruginosa san-ai: the process comparison analysis by statistical approach

Pseudomonas aeruginosa was repeatedly reported as powerful producer of rhamnolipid biosurfactants as well as producer of hydrolytic enzymes. In this study effects of four fermentation factors were evaluated using response surface methodology and experiments were performed in accordance with a four-factor and five-level central composite experimental design. Investigated factors were: fermentation temperature, time of fermentation, concentration of sunflower oil and concentration of Tween? 80. The most important finding was that regression coefficients of the highest values were those that describe interactions between factors and that they differ for lipase and rhamnolipid production, which were both investigated in this study. Production of both metabolites was optimized and response equations were obtained, making it possible to predict rhamnolipid concentration or lipase activity from known values of the four factors. The highest achieved rhamnolipid concentration and lipase activity were 138 mg dm-3 (sunflower oil concentration 0.8 %, Tween? 80 concentration 0.05 %, temperature 30?C, and fermentation time 72 h) and 11111 IU dm-3(sunflower concentration of 0.4 %, Tween? 80 concentration of 0.05 %, temperature of 30?C, and fermentation time of 120 h), respectively.

Influence of sunflower oil on conjugated linoleic acid production byLactobacillus acidophilus andLactobacillus casei

This study was conducted to test the conjugated linoleic acid (CLA) producing potential ofLactobacillus acidophilus NCDC-14 andLactobacillus casei NCDC-19, where sunflower oil (a rich source of linoleic acid) was used as a substrate for CLA production in skim milk at varying concentrations ranging from 0.25–1.0%.Lactobacillus casei produced higher amount of CLA i.e. 11.0 mg/g of fat at a concentration of 1.0% sunflower oil, whereasL. acidophilus produced only 2.73 mg/g of fat. However, at the lower concentration of sunflower oil (0.25%), there was no considerable difference (i.e. 6.92 and 6.73 mg/g of fat forL. casei andL. acidophilus, respectively) in the CLA producing ability of both the cultures, indicating that the increased amount of oil in the medium led to the inhibition of either the growth ofL. acidophilus or the CLA conversion. Hence,L. casei may extend a possibility to be used in the preparation of different fermented milk products for enhanced CLA content.

Conjugated linoleic acid producing potential of lactobacilli isolated from the rumen of cattle

Lactobacilli isolated from the rumen of cattle were subjected to morphological and biochemical characterizations followed by PCR-based identification. Among isolates, Lactobacillus brevis was found to be the most prevalent species in the rumen. For in vitro conjugated linoleic acid (CLA) production, the two isolates of L. brevis and one each of Lactobacillus viridescens and Lactobacillus lactis were selected. The sunflower oil (i.e., 0.25, 0.5 and 1.0%; a rich source of linoleic acid) was added to skim milk as a substrate for CLA production by isolates at 37 degrees C/12 h. L. brevis 02 was found to be the most potential CLA producer (10.53 mg CLA/g fat) at 0.25% concentration of sunflower oil followed by L. brevis 01 (8.27 mg CLA/g fat). However, at higher level of sunflower oil (i.e., 1.0%), L. lactis was the highest CLA producer (9.22 mg/g fat) when compared to L. brevis and L. viridescens. The results indicated that L. brevis and/or CLA production was inhibited with increasing concentration of sunflower oil in skim milk. In contrast, L. lactis and L. viridescens could tolerate the increasing concentrations of sunflower oil and produced higher CLA. Overall, L. brevis extends a possibility to be used as a direct-fed microbial for ruminants to increase the CLA content in milk, however, in vivo trials are needed for validation of results obtained.

Effect of strong electrolytes on edible oils part 1: viscosity of sunflower oil in 1,4-dioxane at different temperatures

The viscosity of sunflower oil in 1,4-dioxane used as a diluent in the presence and absence of strong electrolytes (HCl, NaOH, NaCl) at different temperatures (298K to 323K) was accomplished. The viscosity of sunflower oil was found to increase with the increasing concentration and decreased with the increase in temperature. It was further observed that viscosity of sunflower solution in 1,4-dioxane increases under the influence of electrolytes. The values of Jones-Dole coefficient A and B were evaluated. The positive values of B-coefficient increased with the rise of temperature. This led to conclusion that ion-solvent interactions increase and electrolytes such as HCl, NaOH and NaCl behave as structure breaker in sunflower-1,4-dioxane system. The change in the values of fluidity parameters such as (a, k, α 1 , α 2 , β, β *) with concentration of oil and temperature suggests that fluidity parameters are structural. The energy of activation (ΔE v ), latent heat of vapourization (ΔL v ) and molar volume of oil (V m ) were also calculated. Effect of electrolytes show that, the concentration of electrolytes increases the value of (ΔE v ) and (ΔL v ) whereas the value of molar volume (V m ) decrease with the concentration of oil and electrolytes. In brief, unsaturations of fatty acids of oil are responsible for the changes in the values of different parameters determined. The results for (ΔE v ) and (ΔL v ) are influenced by the concentration of sunflower oil. Journal of Applied Sciences and Environmental Management Vol 9(2) 2005: 15-21

Spectral Variable Selection for Partial Least Squares Calibration Applied to Authentication and Quantification of Extra Virgin Olive Oils Using Fourier Transform Raman Spectroscopy

The limits of quantitative multivariate assays for the analysis of extra virgin olive oil samples from various Greek sites adulterated by sunflower oil have been evaluated based on their Fourier transform (FT) Raman spectra. Different strategies for wavelength selection were tested for calculating optimal partial least squares (PLS) models. Compared to the full spectrum methods previously applied, the optimum standard error of prediction (SEP) for the sunflower oil concentrations in spiked olive oil samples could be significantly reduced. One efficient approach (PMMS, pair-wise minima and maxima selection) used a special variable selection strategy based on a pair-wise consideration of significant respective minima and maxima of PLS regression vectors, calculated for broad spectral intervals and a low number of PLS factors. PMMS provided robust calibration models with a small number of variables. On the other hand, the Tabu search strategy recently published (search process guided by restrictions leading to Tabu list) achieved lower SEP values but at the cost of extensive computing time when searching for a global minimum and less robust calibration models. Robustness was tested by using packages of ten and twenty randomly selected samples within cross-validation for calculating independent prediction values. The best SEP values for a one year's harvest with a total number of 66 Cretian samples were obtained by such spectral variable optimized PLS calibration models using leave-20-out cross-validation (values between 0.5 and 0.7% by weight). For the more complex population of olive oil samples from all over Greece (total number of 92 samples), results were between 0.7 and 0.9% by weight with a cross-validation sample package size of 20. Notably, the calibration method with Tabu variable selection has been shown to be a valid chemometric approach by which a single model can be applied with a low SEP of 1.4% for olive oil samples across three different harvest years.

Intercepted Solar Radiation during Seed Filling Determines Sunflower Weight per Seed and Oil Concentration

A reduction in intercepted photosynthetically active radiation (PAR) during a short period of seed filling could affect weight per seed and oil concentration in sunflower (Helianthus annuus L.) depending when the reduction occurs. The main objectives of this work were (i) to determine the period of time during which intercepted PAR most influences final weight per seed and oil concentration, and (ii) to establish and validate relationships between intercepted PAR during such a period and oil yield components. Intercepted PAR was modified by shading (0, 50, or 80%) field grown crops during different periods of seed filling. Data from published and unpublished field experiments, in which intercepted PAR per plant was changed during the entire seed filling period by shading, thinning to reduce plant population, or both, were also used. All experiments were performed under adequate water and nutrient conditions. A reduction in intercepted PAR during 7 to 10 d of seed filling affected weight per seed and oil concentration. The developmental interval during which final weight per seed and oil concentration were best accounted for by accumulated intercepted PAR (r2 > 0.805) began at 250°C d and ended at 450°C days after flowering (DAF). The established relationships were validated with independent data. The relationships obtained in this work help to explain the effects of environment and crop management (sowing date, location, year) on oil yield variation.