Nutritional value of rapeseed oil and its high oleic/low linolenic variety – A call for differentiation

To offer the best choice of healthy and acceptable food to the consumer a coordination of plant breeding, food processing and nutrition science is required. Here the nutritional aspects of the high oleic/low linolenic (HOLLi) varieties of rapeseed with a low α‐linolenic acid content of about 3% are reviewed. The content of α‐linolenic acid amounting to around 9% is the hallmark of the positive nutritional value of the original (erucic acid free) 00 varieties of rapeseed oil (“canola” quality in North America). n‐3 fatty acids are endowed with the property to protect the cardiovascular system from chronic disease and the consumption of food containing n‐3 fatty acids is explicitly recommended by national and international nutritional and medical authorities. Although the use of HOLLi with a low n‐3 fatty acid content can be unavoidable for specific purposes, because of technological and health considerations the continuous future consumption of the original rapeseed oil with around 9% of α‐linolenic acid by the consumer should have high priority from the standpoint of public health. To pursue this aim confusion of the consumer must be avoided by creating a new name and a new brand for HOLLi varieties.     

Alternate oils in fish feeds

Nearly half of the fish consumed as food worldwide are raised on fish farms rather than caught in the wild, as shown by FAO statistics. The increasing aquaculture of predatory carnivorous fish demands new sources of feed constituents, particularly oils at the moment. Common terrestrial plant oils contain only traces of the long‐chain polyunsaturated fatty acids. In connection with fish feed, especially the lack of n‐3 “marine fatty acids” is obvious. Recommendations on the required amounts of the fatty acids DHA (22:6n‐3) and EPA (20:5n‐3) exist from 1994. When plant oil‐based diets are fed during the growing phase and replaced by a fish oil‐based diet during a period prior to slaughter, most of the beneficial lipid composition of fish in terms of human dietary recommendations is restored. Little attention has been focused on the fish welfare in connection to substitution of dietary oil sources, and studies are still scarce. New fish diets will rely heavily on the use of alternate ingredients such as plant oils also for carnivorous cold‐temperate water fish species. In the future, an addition of synthetic or GMO‐produced “marine” fatty acids is a possible scenario. The aim of this review is to highlight some plant oils used in fish feeds, with special emphasis on compounds other than fatty acids. We also include some results from an ongoing study, where the effect of dietary soy oil on gonad maturation in Atlantic cod (Gadus morhua) is indicated.     

Composition of liver fats of mature and embryo sharks (galeocerdo tigrinus)

1. Two liver fats, one from the “mother” and the other from the “embryo” shark (Galeocerdo tigrinus), have been studied. Their component fatty acids are reported.
2. The mixed fatty acids from each of the fats were first resolved into groups of acids of varying unsaturation by the lithium salt acetone and/or lead salt alcohol methods. The methyl esters of each of these groups of acids were fractionated through the Longenecker's E.H.P. column.
3. The two fats are found to belong to the fourth group of Tsujimoto's classification of the Elasmobranch fish liver fats. The “mother” shark liver fat contains 43.3% saturated and 56.7% unsaturated acids. The “embryo” shark liver fat contains 39.1% saturated and 60.9% unsaturated acids. Palmitic acid was about 25% in both of the fats.
4. A possible explanation for the less unsaturation and the absence of higher polyethenoids in the “embryo” liver fat is given.

     

Synthesis of alkyl‐branched fatty acids

Alkyl‐branched fatty compounds are of interest for industrial products in the cosmetics and lubricant areas. In this review, clay‐ and zeolite‐catalyzed isomerizations of unsaturated fatty compounds, especially of oleic acid, are discussed. While clay‐catalyzed reactions give most complex mixtures of dimeric fatty acids and of monomeric so‐called “isostearic acid”, the zeolite‐catalyzed process yields preferentially an isomeric mixture of isostearic acids having the methyl branch on the 8–14 positions of the alkyl chain. Synthetically useful additions of alkyl radicals can only be performed on ω‐unsaturated fatty compounds, whereas perfluoroalkyl iodides were added to fatty compounds with terminal as well as internal double bonds using electron transfer‐initiated radical addition reactions. Electrophilic additions of alkyl carbenium ions generated by decomposition of alkyl chloroformates by ethylaluminum sesquichloride give well‐defined alkyl‐branched oleochemicals with good yields.     

Produkte der Dimerisierung ungesättigter Fettsäuren VIII: Über die Zusammensetzung der Fraktion der “Intermediates” bei der Fettsäuredimerisierung

Products of Dimerisation Unsaturated Fatty Acids VIII: The Fraction of “Intermediates” Obtained by Dimerisation of Unsaturated Fatty Acids The fraction of “intermediates” which is obtained by dimerisation of unsaturated fatty acid contains straight chain saturated fatty acids with 20-24 carbon atoms as well as methyl branched isomers thereof. The production of these compounds is probably caused by the presence of small amounts of monounsaturated fatty acids with 20-24 carbon atoms in the starting material. The fraction of “intermediates” contains in addition monocarboxylic acids with 36 carbon atoms. These are probably formed after dimerisation by an intramolecular cyclisation reaction under participation of one carboxylic group, followed by hydrogenation of the produced carbonyl group. Finally the formed alcoholic group is eliminated as a water molecule, and the produced double bond is hydrogenated.     

Associations between Oil Yield and Profile of Fatty Acids,Sterols, Squalene,Carotenoids, and Tocopherols in Seed Oil of Selected Japanese Quince Genotypes during Fruit Development

Tocopherols, phytosterols, carotenoids, and squalene are present in mature seeds of Japanese quince. Yet, little is known about the relationship between these compounds and oil yield during fruit and seed development. The profile change of lipophilic compounds during fruit and seed development in Japanese quince cultivars “Darius,” “Rondo,” and “Rasa” is investigated. It is shown here that during fruit and seed development, there is a significant reduction, three‐ to over tenfold, in the concentration of minor bioactive compounds in seed oil. It is recorded that delay between synthesis of tocopherols and oil in Japanese quince seeds during the fruit development results in a logarithmic relationship between the oil content and tocopherols concentration in the seed oil (R² = 0.980). Similar trends are observed between oil yield and phytosterols, and carotenoids (R² = 0.927 and R² = 0.959, respectively). The profile of fatty acids during the development of the seeds significantly is changed. The reduction of linoleic, palmitic, and gondoic acids levels and increment of oleic acid is noted. The oil content, profile of fatty acids, and concentration of bioactive compounds in all three genotypes of Japanese quince do not change significantly statistically during the last month of fruit development. Practical Applications: Some fruits are harvested at different degrees of maturity mainly due to a logistic issue and uneven ripening of fruits, which affects the chemical composition of whole fruit including seeds. Therefore, it would be good to know how the chemical composition is changing in plant material during development especially in the last month before harvest. Production of Japanese quince continues to rise year to year and with it the volume of generated by‐products such as seeds. This study demonstrates how it changes the oil content, profile of fatty acid, and concentration of tocopherols, squalene, phytosterols, and carotenoids in the seeds and seed oil of three Japanese quince cultivars “Rondo,” “Darius,” and “Rasa” during plant development. The provided information can be very useful for the manufactories oriented on the processing of by‐products, mainly seeds, generated by other branches of industry, for instance, fruit‐processing.     

Properties of alkyl esters base on castor oil

Castor oil is a non‐traditional raw material for the preparation of methyl and ethyl esters of higher fatty acids as alternative fuels for diesel engines. Castor oil contains ricinoleic acid (12‐hydroxy octadecene acid) with a major share of about 90%. The article presents the parameters of castor oil‐based methyl esters (COME) and ethyl esters (COEE) defined by the standard EN 14 214. The densities of COME and COEE are higher than the limit defined by the standard EN 14 214. The viscosities are more than twice as high as the limit value. The cetane numbers are lower than defined by the standard EN 14 214. For the remaining parameters, COME and COEE meet, in principle, the standard EN 14 214. The presence of the free hydroxyl group has virtually no effect on the values of such parameters as carbon residue, filterability at low temperatures and oxidation stability, for which some influence was expected. The physicochemical parameters of the castor oil esters are discussed in comparison to the analogous esters of high‐oleic sunflower oil, which contain about 80% of oleic acid. Both the methyl and ethyl esters of high‐oleic sunflower oil meet the standard EN 14 214 in all prescribed parameters.     

Die Zusammensetzung ”︁oxidierter Fettsäuren”, ihr Gehalt als Beurteilungsgrundlage für erhitzte Fette und ihre Beziehung zur Verseifungsfarbzahl

Composition of “Oxidized Fatty Acids”, Their Content as a Basis for the Evaluation of Heated Fats and Their Relationship to Saponification Colour Number “Oxidized fatty acids”? obtained from various thermally oxidized fats according to DGF method C-III 3 (68) have been investigated. Empirical formula determined from molecular weight, and C-, H- and O-content, and the possible structural formulas are discussed. During oxidation the content of ?oxidized fatty acids”? increased parallel to the increased in saponification colour number E100%, 1 cm/470 nm. Contrary to other investigations, it has been proved that the relationship between saponification colour number and “oxidized fatty acids? is not affected by the material fried. Thus it is possible to use saponification colour number in combination with acid value as basis for the evaluation of heated fats.     

“Dicranin” in the Membrane Phospholipids of a Dicranaceae and Pottiaceae Moss Member of the Eastern Himalayan Biodiversity Hotspot

The phospholipids of two moss samples Oreoweisia laxifolia (Hookf.) Kindb. (family‐Dicranaceae Schimp.) and Leptodontium viticulosoides (P. Beauv.) Wijk & Margad (family‐Pottiaceae Schimp.) of the Eastern Himalayan Biodiversity Hotspot were investigated to find out any peculiarity in their fatty acid profiles. Detailed analysis of phospholipid classes and the respective fatty acids was performed using high‐performance thin‐layer chromatography and gas chromatography‐mass spectrometry. An array of different saturated and unsaturated fatty acids were detected in both the samples. Although it has been proposed previously that acetylenic fatty acids are associated only with triacylglycerol of storage lipids, the most striking observation of the present investigation is the abundance of an acetylenic fatty acid, octadeca‐6‐yn‐9,12,15‐trienoic acid (18:4a), or Dicranin, in the phospholipids of both the mosses. The position of the triple bond in the hydrocarbon chain of the fatty acids was confirmed by dimethyloxazoline derivatization of fatty acids and their characteristic mass fragmentation pattern. The occurrence of Dicranin in phospholipids and in the Pottiaceae family is reported for the first time, with substantial explanations of the observed results. This may raise the issue of rethinking “Dicranin” as a chemotaxonomic marker of Dicranaceae.     

Omega‐3 Index and cardiovascular disease prevention: principle and rationale

A clearer picture emerges when correlating blood levels of marine omega‐3 fatty acids (eicosapentaenoic acid, EPA, and docosahexaenoic acid, DHA) to cardiovascular events than when correlating dietary intake. Therefore, the Omega‐3 Index has been proposed as a novel biomarker of cardiovascular risk. The Omega‐3 Index is defined as the percentage of EPA+DHA in red blood cell (RBC) fatty acids. The definition includes the analytical method, which has been standardized (HS‐Omega‐3 Index) similarly to other routine clinical laboratory parameters. Completed and ongoing research projects (more than 80) indicate that the HS‐Omega‐3 Index presently fulfils many criteria for a novel biomarker for cardiovascular risk. Because the research results are obtained with a standardized methodology, introducing the HS‐Omega‐3 Index into clinical routine is possible.     

Analysis of oxidized biodiesel by 1H‐NMR and effect of contact area with air

Biodiesel is continuously gaining attention and significance as an alternative diesel fuel. An important issue facing biodiesel is fuel stability upon exposure to air due to its content of unsaturated fatty acids. Numerous factors influence the oxidative stability of biodiesel, and several methods for its assessment have been developed. In the present work, a defined amount of biodiesel (methyl soyate) was heated in open beakers, with the only difference being the size of the beaker, i.e. the surface area of the biodiesel exposed to air. Biodiesel oxidized in this fashion was analyzed by ¹H‐NMR, kinematic viscosity and acid value. Acid values and kinematic viscosity increased with time and surface area. A previously developed ¹H‐NMR procedure was used to evaluate the unsaturation and “residual” fatty acid composition. The amounts of saturated fatty acids determined by this method increased, with monounsaturated and diunsaturated species increasing and then decreasing with time. After “flash” (3 h, 165 °C) oxidation, NMR shows the greatest effect on saturates and compounds with two double bonds, the former increasing and the latter decreasing. The double bond originally located at δ15 in 18:3 is largely retained, showing that other double bond positions in 18:3 are initially affected by oxidation. The methyl ester signal decreases, coinciding with the increase in acid value. An increasingly strong absorption was observed in the UV‐VIS spectra. Increasing surface area accelerated oxidation and affected fatty acid composition.     

Effects of milk fat replacement by PUFA enriched fats on n‐3 fatty acids,conjugated dienes and volatile compounds of fermented milks

A study was carried out to determine the profiles of fatty acids in fermented milks and dairy derivatives made with milk fat substituted by polyunsaturated fatty acid (PUFA)‐enriched fat. In order to improve the organoleptic properties of those products, whey protein concentrates (WPC) were added during the manufacturing process. Interest was focused during manufacturing and storage period on the contents of “healthy” fatty acids, mainly conjugated linoleic acid and n‐3 PUFA. Contents of these fatty acids were not affected by the manufacture practices and neither did addition of WPC during manufacturing nor cold storage cause their decrease. Percentages of total n‐3 fatty acids in fat from dairy derivatives enriched in PUFA after 21 d of storage (1.45%) were very close to those obtained before processing (1.39%). Contents did not differ either substantially when WPC were added during manufacturing (1.46%). The increase of volatile compounds was also examined. Although a slight decrease in the total volatile content was observed, percentages of different compounds were not modified when milk fat was substituted by PUFA enriched fat.     

Specific molecular and colloidal structures of milk fat affecting lipolysis,absorption and postprandial lipemia

In milk fat, fatty acids are located at specific positions on the triacylglycerol backbone. The sn‐2 position contains most saturated long‐chain fatty acids, while the sn‐3 position contains short‐chain fatty acids. Moreover, these triacylglycerols are structured as milk fat globules surrounded by their native membrane containing phospholipids. This native structure can be modified by the dairy processes to generate various possible colloidal structures with milk fat. The structure of triacylglycerols and the milk fat ultrastructure can impact on fatty acid digestion and absorption, which has a potential effect on cardiovascular risk factors linked to postprandial hypertriglyceridemia. The review points out the impact of the triacylglycerol structure and the ultrastructure of milk fat on these risk factors.     

Producing the omega‐3 fatty acids DHA and EPA in oilseed crops

There is increasing consumer demand for the omega‐3 fatty acids docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) because of their well‐recognized benefits for human health and the observation that current western diets are deficient in these important polyunsaturated fatty acids (PUFAs). This has led to the need for additional cost‐effective and sustainable dietary sources of DHA and EPA beyond the traditional resource, oceanic fish. Recent advances in plant biotechnology have shown that DHA and EPA can be produced in vegetable oils using two approaches involving different sets of genes. One approach incorporates genes that direct sequential rounds of desaturation and elongation of native plant fatty acids. The other approach uses microalgal PUFA synthase genes to make DHA de novo without the need for native fatty acid precursors. These strategies offer the potential for sustainable production methods for DHA and EPA via land‐based oilseed crops.     

A method of concentration estimation of trienes,tetraenes, and pentaenes in evening primrose oil

There is no simple method available to estimate the concentration of conjugated fatty acids (CFA) with more than two double bonds in plant oils, because there are no commercially available complete sets of CFAs standards needed for such analysis. This paper presents such a method based on the absorption and fluorescence spectra of available CFAs standards and a computer program calculation. Using this method, the concentrations of the α‐eleostearic acid (conjugated trienoic acid (ELA) 8.8 × 10^?4 mol/L) and cis‐parinaric acid (conjugated tetraenoic acid (PnA) 3.5 × 10^?5 mol/L) in evening primrose oil were estimated. The accuracy of the calculation method is around 10%. Practical applications: This is the first report about the existence of CFAs in evening primrose oil. The described method estimates the total concentration of trienes, tetraenes, and pentaenes in evening primrose oils without using HPLC or other analytical methods. These CFAs are important from a health point of view. They are not synthesized by the human body. Therefore, plant oils containing these fatty acids (FA) are very valuable. Knowledge about the concentrations can be utilized to prepare a mixture of the plant oils with a favourable n‐3 to n‐6 FAs ratio and in addition containing CFAs.     

Über physiologische Wirkungen „oxidierter Fettsäuren”︁ aus geblasenen Ölen

Physiological Actions of “Oxidized Fatty Acids” from Blown Oils Feeding experiments were carried out on 60 rats for 189 days using “oxidized fatty acids” which were isolated by the DGF-method C-III 3 (53). The “oxidized fatty acids” corresponded to oxy-dimeric linoleic acid with respect to molecular weight and elemental formula. The investigations included weight gain of the experimental animals, histological examination of the internal organs, and composition of depot and cellular fats. The results of these studies are reported. Growth retardations were observed as a clear indication of harmful action of “oxidized fatty acids”.     

Physical‐chemical characteristics and oxidative stability of oil obtained from lyophilized raspberry seed

Fresh raspberry (Rubus idaeus), cultivar Willamette, was freeze‐dried (lyophilization). A byproduct of lyophilization is “fine dust” of raspberry consisting of finely ground raspberry fruit body and seed. The seeds were separated. The seed oil was isolated and its physical and chemical characteristics were determined. Parameters that characterize the seed and quality of the oil were examined, including fatty acid composition, oxidative stability under different storage conditions, and radical‐scavenging activity. The fatty acid composition was determined by GC/FID and the contents of the dominant fatty acids were found as: oleic 16.92%, linoleic 54.95%, and α‐linolenic acid 23.97%. The oxidative stability of the oil was poor. The induction period by Rancimat test at 100 °C was 5.2 h. The radical‐scavenging activity is similar to that of resveratrol [1,3‐benzenediol 5‐(1^E‐2‐4‐hydroxy‐phenyl‐ethyl)]. Although this product is used in the candy industry, it would be far more useful if raspberry oil of satisfactory quality could be extracted. This paper demonstrates that sifted lyophilized seeds can be used for the extraction of oils. This process allows for maximal usage of the byproducts, reduces losses and it increases the development of new products.     

Virgin Olive Oils from Super-High-Density Orchards in California: Impact of Cultivar,Harvest Time,and Crop Season on Quality and Chemical Composition

The impact of cultivar, harvest time, and crop season on olive fruit characteristics and olive oil quality and minor components composition is assessed for super-high-density “Arbequina”, “Arbosana”, and “Koroneiki” in California, United States, during 2016, 2017, and 2018. Fruit oil content reaches a plateau in November for “Arbequina” and “Arbosana,” while the accumulation rate keeps constant until early December for “Koroneiki.” Free fatty acids, diacylglycerols, pyropheophytins, and ΔK are not affected by any of the considered factors. Peroxide value, K_232, and K₂₇₀ decreases with harvest time. Chlorophylls content decreases with harvest time, more rapidly in “Arbequina” and “Arbosana” than in “Koroneiki”. Cultivar is the main factor affecting the fatty acid profile. “Koroneiki” has the highest oleic acid content, followed by “Arbosana” and “Arbequina.” Phenolic and volatile compounds are profoundly affected by cultivars and crop seasons, suggesting the relevance of these factors on the sensory and nutritional properties of virgin olive oil from super-high-density cultivars. Stepwise linear discriminant analysis allows selecting suitable markers among fatty acids, phenolic, and volatile compounds for cultivar, crop season, and harvest time discrimination. Practical Application: This paper constitutes the first report of a multiyear study considering quality and composition in bioactive compounds of super-high-density “Arbequina,” “Arbosana,” and “Koroneiki,” planted in California, USA. This information helps processors understand the differences in oil made from the most common super-high-density cultivars along harvest times and for growers to make planting and harvesting decisions.     

Bactericidal activity of certain fatty acids

Fatty acids in the C₉ to C₁₂ range are bactericidal to a number of different organisms, and this activity is markedly enhanced with increasing acidity. Optimum bactericidal activity toStaphylococcus aureus was exhibited by undecylic acid. Since the activity is of the same order as that of the quaternary ammonium germicides in alkaline solution, an explanation for both types of germicidal activity is presented in which the bacteria or some protein essential to the bacteria are considered to be “suffocated” by a “coating” of fatty groups in chemical combination with the protein. The application of these findings to bactericidal activity encountered in rancid fats is discussed briefly in connection with the oxidative degradation of oleic acid derivatives to pelargonic acid. In addition, the possible usefulness of the bactericidal activity as a microbiological assay method for certain fatty acids is pointed out.     

Interlaboratory Assessment of Dried Blood Spot Fatty Acid Compositions

Dried blood spots for fatty acid profiling are increasing in popularity; however, variability in results between laboratories has not been characterized. Whole blood from two subjects (low and high n-3 polyunsaturated fatty acid [PUFA] status) was collected, 25 μL applied to butylated hydroxytoluene (BHT)-treated chromatography strips, dried in air, and shipped to five laboratories. Results were reported as “routine” (typical fatty acids for each laboratory) or “standardized” (a set of 19 fatty acids), and outliers and variability (%CV) were determined. Five and eight outliers of a possible 91 measures each were identified by routine and standardized reporting, respectively, including eicosapentaenoic acid (EPA, 20:5n-3) in the low n-3 PUFA sample and arachidonic acid in the high n-3 PUFA sample. By standardized reporting, no outliers were identified for EPA or docosahexaenoic acid (DHA, 22:6n-3), and %CV decreased from 8.6% to 6.0% and 9.1% to 6.6% for EPA and 10.5% to 7.2% and 10.5% to 6.6% for DHA in the low and high n-3 PUFA sample, respectively. In conclusion, fatty acid profiles yielded few outliers, and standardization of reporting reduced the variability between laboratories.