Search

Canola is the major oilseed crop of Canada. The de-oiled material is an important by-product due to its rich phenolic profile and high protein content. This co-processing stream from canola is primarily utilized as animal feed but represents an invaluable source of nutraceuticals. Microwave-assisted solvent extraction (MAE), as a green extraction method, has received considerable attention in recent times. The ease of use and application of many solvents at the same time makes the MAE one of the best methods for studying multiple solvents at the same time. The formation of canolol, from sinapine and sinapic acid, is primarily dependant on temperature which favors the decarboxylation reaction. Hence, MAE using green extractants can be used to enhance the yield of canolol. This study examined the effects of different pre-treatment temperature-time combinations of 140, 150, 160, and 170℃ for 5, 10, 15, 20 and 30 minutes on the extraction of canolol and other canola endogenous phenolic compounds. Three antioxidant assays assessed the antioxidant activity of the different extracts obtained by MAE confirming the microwave as a novel and versatile instrument for enhancing the yield of canolol. Improvements in the antioxidant activity of the different extracts further established the efficacy of the current method for isolating important natural phenolic derivatives for utilization by the nutraceutical industry.

Roasting of mustard seeds prior to oil extraction is a well-documented unit operation essential to produce canolol and other lipophilic sinapates. This study investigated the effectiveness of air frying as a seed roasting treatment operation for enhancing the recovery of lipophilic sinapates from various mustard samples and fractions/products. Air frying of seeds, powder, cake, bran, and flour from different mustard varieties was carried out at temperature-time combinations of 160, 170, and 180°C for 5, 10, 15, and 20 min, respectively. Oil was extracted using the Soxtec method. Lipophilic sinapates were extracted from the oil using equal volumes of hexane to methanol 70% (v/v) and quantified by high performance liquid chromatography-diode array detection (HPLC-DAD). The total phenolic content (TPC) and antioxidant activity of the oils were also evaluated. The results showed a time-temperature dependency for the recovery of major oil-soluble sinapates in all mustard samples and fractions. The optimum air frying condition 180°C for 15 min produced the maximum yield of canolol as well as other unidentified oil-soluble sinapates (retention time (RT)-7.7, RT-11.50, RT-14.95, and RT-16.24 min). The oil from lower grade yellow mustard seeds (LGYMS) roasted at 180°C for 20 mins specifically had the highest TPC (3402.22 ± 58.79 mg GAE/g oil), while LGYMS oils generally showed better antioxidant activities (2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric ion reducing antioxidant power (FRAP), and inhibition of linoleic acid oxidation) but were lower in metal ion chelating capacity. This information would be beneficial to the oil industry because air frying generated valuable canolol and other antioxidant lipophilic sinapates from mustard varieties and their fractions. PRACTICAL APPLICATION: A major limitation in the application of natural extracts in vegetable oils is the poor lipophilic nature of phenolic compounds. This study employed a new thermal treatment (air frying) in the recovery of canolol and other lipophilic antioxidants. Such treatments can enrich mustard-based ingredients with canolol and other lipophilic antioxidants for domestic and industrial applications.

Understanding the complicated emulsion microstructures by microscopic images will help to further elaborate their mechanisms and relevance. The formidable goal of the classification and quantification of emulsion microstructure appears difficult to achieve. However, object detection algorithm in deep learning makes it feasible. This paper reports a new technique for evaluating Pickering emulsion properties through classification and quantification of the emulsion microstructure by object detection algorithm. The trained neural network models characterize the emulsion droplets by distinguishing between different individual emulsion droplets and morphological mechanisms from numerous microscopic images. The quantified results of the emulsion droplets presented in this study, provide details of statistical changes at different concentrations of the Pickering interface and storage temperatures enabling elucidation of the mechanisms involved. This methodology provides a new quantitative and statistical analysis of emulsion microstructure and properties.

De-oiled canola meals are sources of protein-containing flavor-active phenolic compounds. Conventional canola oil processing utilizes an excess amount of solvents and is associated with the release of high-intensity bitter flavor-active phenolic compounds, limiting the use of the canola meal. Recent advances in the extraction and isolation of the bitter favor-active phenolic compounds from canola by-products produce protein isolates, however, would benefit the industry by producing a side-stream ingredient rich in phenolics. High temperature and pressure-aided processing, namely the accelerated solvent extraction (ASE) was investigated to extract the flavor-active bitter molecules from the canola meal. The extractability of flavor-active phenolic compounds including the major sinapates, kaempferol derivatives, and other thermo-generative compounds including thomasidioc acid (TA) was evaluated. The effects of temperature, solvent extractant and concentration, and the particle size of the meal, were examined on the extraction efficiency of these phenolic compounds. Extraction temperature (180oC) was the primary determinant (p

Phosphorus, an essential nutrient, performs vital functions in skeletal and non-skeletal tissues and is pivotal for energy production. The last two decades of research on the physiological importance of phosphorus have provided several novel insights about its dynamic nature as a nutrient performing functions as a phosphate ion. Phosphorous also acts as a signaling molecule and induces complex physiological responses. It is recognized that phosphorus homeostasis is critical for health. The intake of phosphorus by the general population world-wide is almost double the amount required to maintain health. This increase is attributed to the incorporation of phosphate containing food additives in processed foods purchased by consumers. Research findings assessed the impact of excessive phosphorus intake on cells' and organs' responses, and highlighted the potential pathogenic consequences. Research also identified a new class of bioactive phosphates composed of polymers of phosphate molecules varying in chain length. These polymers are involved in metabolic responses including hemostasis, brain and bone health, via complex mechanism(s) with positive or negative health effects, depending on their chain length. It is amazing, that phosphorus, a simple element, is capable of exerting multiple and powerful effects. The role of phosphorus and its polymers in the renal and cardiovascular system as well as on brain health appear to be important and promising future research directions.

The majority of the bioactive compounds present in canola seeds are phenolic compounds. They are present as aglycones, glycosides, monomers, polymerized structures, or as free or matrix-bound compounds. Conventional methods of extraction utilize an excessive amount of organic solvents and require high energy input. Current environmental issues associated with organic solvent disposal demand alternative methods for the extraction of phenolic compounds that are environmentally friendly and energy-efficient. Green technology has identified a number of alternative methods suitable for the extraction of phenolic compounds. This chapter will review those alternative green methods suitable for the extraction of phenolic compounds from canola and rapeseed. Such methods include ultrasonic extraction, microwave extraction, accelerated solvent extraction, subcritical water extraction, and supercritical fluid extraction.

Adequate thiamin levels are crucial for optimal health through maintenance of homeostasis and viability of metabolic enzymes, which require thiamine as a co-factor. Thiamin deficiency occurs during pregnancy when the dietary intake is inadequate or excessive alcohol is consumed. Thiamin deficiency leads to brain dysfunction because thiamin is involved in the synthesis of myelin and neurotransmitters (e.g., acetylcholine, γ-aminobutyric acid, glutamate), and its deficiency increases oxidative stress by decreasing the production of reducing agents. Thiamin deficiency also leads to neural membrane dysfunction, because thiamin is a structural component of mitochondrial and synaptosomal membranes. Similarly, in-utero exposure to alcohol leads to fetal brain dysfunction, resulting in negative effects such as fetal alcohol spectrum disorder (FASD). Thiamin deficiency and prenatal exposure to alcohol could act synergistically to produce negative effects on fetal development; however, this area of research is currently under-studied. This minireview summarizes the evidence for the potential role of thiamin deficiency in fetal brain development, with or without prenatal exposure to alcohol. Such evidence may influence the development of new nutritional strategies for preventing or mitigating the symptoms of FASD.

Canola meal, a by-product of oil pressing, is a rich source of phenolic antioxidants. However, its use in the food and feed sector is still limited by the need for greener, sustainable, and more cost-effective extraction methods. This study used accelerated solvent extraction (ASE) to enhance the extraction efficiency of the phenolic antioxidants. The high selectivity and short extraction time associated with ASE were ideal for obtaining high yields of these antioxidants. The structure-based activity of phenolic compounds may be influenced by the high pressure and temperature of the greener ASE process. The present study evaluated the effect of temperature (140, 160, and 180 °C) and pressure (1,500 psi) on the extraction and yield of phenolic compounds from canola meal as well as the solvent type (ethanol and methanol) and concentration (30%, 40%, 60%, and 70% v/v). Antioxidant activity was determined by 2,2-diphenyl-1-picrylhydrazyl, ferric reducing/antioxidant power assay, and ion-chelating activity. The highest yield of phenolic compounds was obtained with 70% methanol (20.72 ± 1.47 mg SAE/g DM [milligrams of sinapic acid equivalents per gram of dry matter]) and 70% ethanol (24.71 ± 2.77 mg SAE/g DM) at 180 °C temperature. A similar trend was observed for the antioxidant activity of the extracts and their total flavonoid content. The structure-based antioxidant activity of the extracts examined increased with the increase in the percentage of the extracting solvent (P > 0.05). This study established ASE as an efficient green method for extracting phenolic compounds from canola meal, with potential application for the production of natural bioactive compounds from underutilized agricultural by-products. PRACTICAL APPLICATION: ASE is an efficient eco-friendly method for extracting phenolic compounds from agricultural by-products such canola meal. Under the conditions of high pressure and temperature, ASE significantly improved the yields of phenolic compounds, sinapine, sinapic acid, and canolol. Under these conditions, water, as an extractant, was not effective in extracting sianpine. Moreover, it was much less effective than both 70% ethanol and 70% methanol in extracting sinapine or canolol. These phenolic compounds are of great interest as natural antioxidants for enhancing the shelf life of food products. They also represent new sources of neutraceuticals for improving human health.

Canola by-products have considerable potential as functional ingredients and antioxidants due to the presence of unique phenolic compounds. Thus, extraction of flavor-active phenolics present in canola by-products is important for their co-production and valorization. The quantity and quality of these unique phenolic compounds could affect the sensory and organoleptic properties of any product or ingredients derived post-processing of the canola by-products. This study evaluated, both quantitatively and qualitatively, the formation of these flavor-active compounds under pressurized temperature processing. Particle size, extraction temperature, type of solvent extractants (70%v/v methanol or ethanol), were factors examined for extracting the major flavor-active phenolic compounds including thomasidioic acid (TA), kaempferol 3-O-β-sophoroside (KS), kaempferol 3-O-(2‴-O-sinapoyl-β-sophoroside) (KSS). Two other kaempferol derivatives, kaempferol 3-(2″-hydroxypropionylglucoside)-4′-glucoside (K-4-G) and kaempferol 3-[2″-glucosyl-6″-acetyl-galactoside] 7-glucoside (K-7-G) were also tentatively identified in the extract. The results confirmed that extraction temperature and solvent type had a significant impact (p

Ultrasonic treatment was applied to reduce chlorophyll of cold-pressed hempseed oil in conjunction with various clays. Bleaching clays such as bentonite (activated/non-activated), sepiolite and clay from a canola oil refining industry (industrial clay) were used. Ultrasonic bleaching of hempseed oil for 20 min at 20, 40 and 60% power (expressed as ultrasound amplitude) with bleaching clays (40 g/kg) reduced chlorophyll in decreasing order of effectiveness from industrial clay > activated bentonite > sepiolite > non-activated bentonite together with an increase in ultrasound power to 40%. At 20% ultrasound power, chlorophyll reduction (%) was found to be 99.4% (industrial clay) > 97.8% (activated bentonite) > 82.7% (sepiolite) > 47.1% (non-activated bentonite). The reduction in total phenolic content was 27.3%, 33.4%, 27.9% and 34.7% when treated at 20% ultrasound power with 40 g/kg clay from canola industry, activated bentonite, non-activated bentonite and sepiolite, respectively. The corresponding reduction in the peroxide value for the oil samples, due to the adsorptive nature of the clay, followed the trend of industrial clay > sepiolite > non-activated bentonite. This process proved promising for impacting hempseed oil color through reduction of chlorophyll.

Phenolic compounds in beer are derived from grains and hops during processing and production. Thus, the total phenolic content (TPC) of beer extracts, from selected Canadian and foreign commercial, and laboratory produced beers were examined and ranged from 3.72 ± 0.23 to 13.73 ± 0.49 mg GAE/100 mL beer. The total flavonoid content (TFC) of the same beer extracts varied from 0.82 ± 0.02 to 5.28 ± 0.04 mg CE/100 mL beer. Of particular interest were the hydroxycinnamic acids (HCAs) and derivatives in beer extracts because of their antioxidant properties. Main HCAs and a key derivative of ferulic acid, 4-vinylguaiacol (4-VG), were identified in beer extracts by high performance liquid chromatography (HPLC). Significant variations in TPC, TFC, HCAs and 4-VG content were observed among the beer extracts. Antioxidant activities of beer extracts, determined by radical scavenging and ferric-reducing assays, were positively correlated (p 0.05). The positive correlation of 4-VG with ABTS radical cation scavenging and reducing power assays is reported first time. These findings suggest that phenolic compounds and a key derivative of the hydroxycinnamic acid, 4-VG, may have the protective role in the beer as an antioxidant.

Crude canolol (CAN) extracted from canola meal by accelerated solvent extraction and phenolic extracts from canola oil deodistillates (DDL) were assessed for their potential to stabilize canola oil during deep-fat frying. Phenolics extracted from DDL with methanol ranged from 0 to 323 μg/g of DDL phenolics. French fries were deep fried in canola oil (3 L) enriched with 200 ppm of BHT, DDL, or CAN at 185 ± 5°C for 5 min. Twelve batches of fries (30 g each) were fried each day, 30 min apart for a total of 6 h of frying for 5 days. Both CAN and DDL extracts exhibited protection against frying oil deterioration compared to BHT with a considerable reduction in the hydroperoxides after the first day of frying. The ability to reduce primary oxidation was highest with CAN followed by DDL compared to BHT and the control (CAN>DD>Control). The total oxidation (TOTOX) and conjugated diene/triene values of oils fried with DDL and CAN were significantly (p

The results of ultrasonic bleaching prove effectiveness in reducing chlorophyll content in cold‐pressed hempseed oil and suggest its potential for prolonging the shelf‐life.

The paper gives a short overview about the production and composition of borage (Borago officinalis) and evening primrose (Oenothera biennis) oil considering special aspects of the production as cold-pressed oil. Both oils are characterized by a remarkable amount of y-linolenic acid, which has some nutritional advantages. The fatty acid composition of evening primrose oil is dominated by linoleic acid with about 72% and about 13% y-linolenic acid, while borage oil consists of twice the amount of γ-linolenic acid and only 38% linoleic acid. The amount of saturated fatty acids is higher in borage oil. The tocopherol composition of both oils is dominated by γ-tocopherol, with borage oil containing twice the amount compared to evening primrose oil.

Summary Flour blends of quinoa-wheat containing 0, 5, 10, 15, and 20% of manually dehulled quinoa meal or flour were evaluated for dough mixing and breadmaking properties and liking of the bread by a small panel. Increasing amounts of quinoa meal or flour increased farinograph absorption and dislike of bread for most of the panel. Dough development time increased with increase in meal but decreased with increase in quinoa flour. At 10% inclusion levels differences in liking from control 100% wheat flour bread were smaller for flour or water extracted meal to most of the panel, than with 10% non-extracted meal. This suggests that 10% inclusion of flour or water extracted meal may have potential for further investigation.

Synthetic antioxidants, butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT), are used far less in edible food products, especially vegetable oils, because of serious health and safety concerns. As a result, there is a much greater dependence on natural indigenous antioxidants, particularly tocopherols, for maintaining the shelf life of edible oils. This chapter reviews the natural antioxidants, including tocopherols, in palm, soybean, canola, and low erucic acid rapeseed oil, peanut, olive, sunflower, corn, and cottonseed oils that protect against oxidative rancidity. The potential of other natural antioxidants, such as obtained from rosemary, sage, and thyme, for enhancing the shelf life of edible vegetable oils, is also included.

The effects of yellow mustard mucilage (YMM) on the functional and rheological properties of buckwheat and pea starch were studied. Addition of YMM resulted in a marked increase of peak viscosity for both buckwheat and pea starches. Dynamic oscillation measurements showed that the storage modulus ( G ′), loss modulus ( G ″) and dynamic viscosity ( η *) of buckwheat and pea starches were increased but tangent δ was decreased by addition of YMM. The gel textures of both starches were markedly changed by the presence of YMM, which resulted in an increase of hardness, adhesiveness and chewiness but a decrease of resilience. Differential scanning calorimetry showed that the presence of YMM slightly increased melting enthalpy (Δ H ) and the phase transition temperature range ( T c – T o ) of buckwheat starch but these did not change much for pea starch. Addition of YMM–locust bean gum mixture (9:1) similarly increased the viscosity of buckwheat and pea starches but decreased gel hardness. The swelling powers of both starches and solubility of buckwheat starch were slightly decreased in the presence of YMM. Addition of YMM slowed the syneresis of buckwheat and pea starch gels.

The effect of yellow mustard mucilage (YMM) on gelatinization and retrogradation of wheat and rice starches were studied. Considerable interactions were observed between YMM and wheat and rice starches which were accompanied by a marked increase in viscosity. DSC studies showed that the presence of YMM did not affect peak gelatinization temperature (Tp) of wheat and rice starches, but slightly increased melting enthalpy (ΔH) and the phase transition temperature range (Tc−T0). Addition of YMM markedly changed wheat and rice starch gel textures by increasing hardness, adhesiveness, chewiness and springiness. The addition of YMM–locust bean gum (LBG) mixture (9:1) similarly increased the viscosity of wheat and rice starches but decreased gel hardness. The swelling power as well as solubilized starch and amylose were decreased for both starches in the presence of YMM. Syneresis in wheat and rice starches was also decreased by the presence of YMM.

The rapid development of China's economy has resulted in a dramatic increase in the production and purchase of instant fried food products by consumers. China's food industry has relied largely on the importation of soybean oil and palm oil. Palm oil is widely used by the commercial food industry because of its high oxidative stability and low cost. In contrast, the demand for rapeseed oil and peanut oil has gradually increased but only for domestic frying. In the future, specialized frying oils with improved stability and function will be developed for industrial and domestic frying in China.

The interactions of yellow mustard mucilage, locust bean gum and gelatin with native and acetylated pea starch were studied by a Brabender viscograph, a Bohlin rheometer and differential scanning calorimetry (DSC). In the presence of mustard mucilage or locust bean gum, the onset temperature of the viscogram shifted to lower temperatures, whereas the final viscosities of the pastes increased markedly for both native and modified pea starch. Gelatin produced only a slight increase in the viscosity of native pea starch, whereas the viscosity of modified pea starch in the presence of gelatin decreased. DSC studies demonstrated that the presence of a hydrocolloid did not change the gelatinization temperature of pea starch. The variation in the viscosity onset temperature, as observed with Brabender, was attributed to an increase in the medium viscosity of a starch/hydrocolloid dispersion. The increase in starch paste viscosity was due to synergistic interactions of starch and gums. Pea starch pastes exhibited the typical shear thinning behaviour and the addition of a hydrocolloid altered the degree of pseudoplasticity of a starch paste. Mustard mucilage, for example, increased the pseudoplasticity of pea starch pastes, and exhibited higher paste viscosities at low shear rates.

Cereal grains and legumes are complex biological structures with incredible importance as human dietary staples worldwide. Postharvest conditions and treatments, including storage, germination, and fermentation, are capable of causing significant biochemical changes that affect the nutritive value of these foods. In this chapter, mature grain and seed structure, as well as macronutrient synthesis, classifications, and storage forms within the seeds are discussed. The effects of storage conditions, and germination and fermentation processes are examined with regard to proximate and micronutrient composition, phytonutrient contents, the presence of anti-nutritional factors, and overall food quality.

This chapter provides the latest information on browning reactions in foods, including mechanisms and methods of control. Since the second edition, the Maillard reaction or glycation has been shown to play an important role in aging and chronic diseases in humans. This chapter has incorporated the latest information on the structure and formation of melanoidins as well as the effect of polyphenols on these polymers. Also included is a discussion of the role that Strecker degradation plays in the conversion of asparagines to acrylamide. Besides the Maillard reaction, this chapter provides an in-depth review of both caramelization and ascorbic acid oxidation.

This chapter reviews those biochemical changes occurring in postharvest fruits and vegetables which affect quality. New developments in plant physiology have been incorporated including regulation of ethylene and genes encoding the enzymes involved in chlorophyll biosynthesis. The latest information on plant cell walls and textural changes during ripening is also included. A new section on flavor, including aroma and taste, has been added, as well as new developments in postharvest storage.

Copyright: © 2012 Eskin NAM. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Oxidative stress is involved in the development of many chronic diseases including cancer. It has been defined as an imbalance between the level of pro-oxidants (reactive oxygen species, ROS) produced during normal metabolism and the organism’s endogenous antioxidant defence system. The role of various natural antioxidant defence systems to minimize oxidative damage caused by these free radicals was established using animal models in which these defence systems were knocked out [1]. This resulted in the promotion of cancer which was attributed to DNA damage by the formation of 8-hydroxy2-deoxyguanosine (8OHdg). Consequently, a concerted effort has been made to establish the efficacy of such traditional antioxidants as vitamins A, E and C, as well as a search for new antioxidants to minimize such damage. Over 200 epidemiological studies strongly associated low consumption of fruits and vegetables with the incidence of cancer suggesting that antioxidants might be a solution [2]. Consequently, should cancer patients be encouraged to take multivitamin supplements as part of their therapy?

This chapter provides an in-depth review of the biochemical changes involved in the conversion of muscle into edible meat and fish. Major advances in our understanding of the nature and structure of muscle over the past two decades have been incorporated into this chapter. The latest information on the mechanisms of postmortem tenderization is included, focusing on the involvement of lysosomal cathepsin, calpains, and proteasomes. The chapter concludes with a comprehensive discussion of meat and fish pigments, including a detailed review of the structure of myoglobins and effective methods of preservation.

Cow‘s milk provides an important source of nutrients for humans, and the flavor of milk is a key parameter of product quality. Fresh milk has a pleasant aroma, flavor, mouth-feel, and aftertaste. The flavor of milk is influenced by various genetic and environmental factors involved in milk production. The flavor composition of milk is complex; it contains at least 400 volatile compounds, including lactones, acids, esters, ketones, aldehydes, alcohols, furans, carbonyls, pyrazines, sulfur compounds, and aliphatic and aromatic hydrocarbons. The off-balance of these volatile compounds in milk can cause off-flavor, which is easily detected by the consumer. Off-flavors in milk can be categorized into heated, light-induced, lipolyzed, microbial, oxidized, transmitted, and miscellaneous. The most common off-flavor issues in the dairy industry, and possible methods to minimize or eliminate these off-flavors, are addressed in this chapter.

Formation of turbidity in canola oil was facilitated with addition of acetone, and a method to measure the sediment content based on the oil turbidity has been developed. Canola oil was mixed with acetone at the ratio of 60:40, and the turbid solution developed in an ice bath for 20 min. The turbidity of the oil solution was determined by a turbidimeter. The relation between turbidity of the oil solution and sediment content was nonlinear and could be correlated by a second-order polynomial. There was no difficulty in the development of turbidity in canola oil solutions in the presence of added lecithin (2%, w/w). However, with added lecithin, turbidity was 23% higher at the same sediment content.

The effect of acetone on phase transition behavior of sediment in canola oil was studied by differential scanning calorimetry under dynamic heating/cooling regimes. The melting temperature of sediment decreased with an increase in the solvent content of canola oil, suggesting an increase in the solubility of sediment in the oil solution. The crystallization of sediment in oil solution was facilitated by acetone, as indicated by the increase in the sediment crystallization temperature. Acetone dramatically reduced the viscosity of canola oil, particularly in the first 30% addition. The reduction of viscosity was far less with further addition of acetone. These results suggested that the optimum range of acetone content needed for sediment precipitation in canola oil would be in the range of 30–40%. A linear relationship was found between the density of canola oil and temperature. The influence of solvent on the density of canola oil/acetone solution can be accounted for by the mixing theory of ideal solutions, whereas the effect of temperature on the dynamic viscosity of oil solution is best described by a modified Arrhenius equation.

The effects of haze composition variation on sedimentation phenomenon in canola oil were studied. Comparisons were made of the physical properties between an oil sediment (S5) and the high- and low-melting fractions obtained by step crystallisation at 32 and 5 °C (F32 and F5). The phase transition behaviour and crystalline characteristics of the sediments were examined by differential scanning calorimetry (DSC), hot-stage microscopy, spectrophotometry, and X-ray diffraction (XRD). The compositions of the sediments were determined by GC-MS. The melting behaviour of S5 resembled that of F5, whereas S5 behaved more like F32 in crystallisation. Oils containing F32 clouded much faster than oils containing F5. The interfacial surface free energies and the XRD patterns were similar for the two fractions, suggesting identical crystalline structures. The molecular origin of the varied phase transition behaviour of the sediments was attributed to the composition variation in waxes, particularly the acid component in the materials.

Publisher Summary This chapter discusses the origin, composition, properties, and utilization of canola and HEAR oils for food purposes. Canola oil (low-erucic acid rapeseed oil or LEAR) is now held by some to be the best nutritional edible oil available. This oil was developed after significant improvement and modification of the original High-Erucic Acid Rapeseed oil (HEAR). Improvements in technology and in the quality of canola seed have resulted in the modification of the definition of canola over the years. At present, the official definition for canola is a seed from B.napus (L.) or B.rapa (L.) that produces “an oil that must contain less than 2 percent erucic acid and solid component of the seed must contain less than 30 micromoles of any one or any mixture of 3-butenyl glucosinolate, 4-pentenyl glucosinolate, 2-hydroxy-3-butenyl glucosinolate, and 2-hydroxy-4-pentyenyl glucosinolate per gram of air-dry, oil-free solid”. Canola oil is the only known edible oil containing one or more fatty acids with a sulfur atom as the integral part of the molecule. Triacylglycerols (TAG) are the most abundant lipid class found in canola oil. Canola oil contains relatively high levels of tocopherols; however, the amounts in finished oil are affected by refining, mainly deodorization, which can reduce the amount by 50%.

Lipoxygenase (LOX) activity was detected in buckwheat extracts, and was shown to have a pH optimum of 6·5. LOX activity was not affected during 6 days of germination. The specific activity increased when ground buckwheat seeds were extracted with 0·01% or 0·1% solutions of calcium chloride or magnesium chloride, compared to extractions with distilled water or 1·0% solutions of either of these salts. Increase in specific activity was greater in the presence of calcium ions compared to magnesium ions. Gamma-irradiation of buckwheat seeds up to 4 kGy resulted in a decrease in LOX activity to a level of approximately 22% of the untreated control, but increased to approximately 43% of the control at a dose of 6 kGy. These results suggest that gamma-irradiation reduces LOX activity, but is not likely to completely prevent lipid oxidation in buckwheat.