Cheaper Oils Research Articles

Analysis of Rice Bran Oil Adulterated with other Edible Oils by GC

Since rice bran oil (RBO) is well-known by consumer and more expensive than other oils, some RBO is adulterated with other cheap oils, such as cottonseed oil (CO), palm oil (PO), sunflower oil (SFO) and soybean oil (SO). The types and content of FAs in RBO changes great after adulterated, this will seriously affect the quality of the rice and the people health. In this study, GC was used to detect the change of fatty acids (FAs) after adulterated with those inferior oils. The analysis will provide a reference for the RBO adulteration problem.

FTIR Spectroscopy and Chemometric Class Modeling Techniques for Authentication of Chinese Sesame Oil

AbstractThis investigation was aimed at developing a rapid analysis method for authentication of Chinese sesame oils by FTIR spectrometry and chemometrics. Ninety‐five sesame oil samples were collected from the six main producing areas of China to include most if not all of the significant spectral variations likely to be encountered in future authentic materials. Two class modeling techniques, the soft independent modeling of class analogy (SIMCA) and the partial least squares class model (PLSCM) were investigated and the data preprocessing techniques including smoothing, derivative and standard normal variate (SNV) tests were performed to improve the classification performance. It was demonstrated that SIMCA and PLSCM can detect various adulterated sesame oils doped with 3% or more (w/w) of other cheaper oils, including rapeseed, soybean, palm and peanut oils. First derivative, second derivative and SNV tests significantly enhanced the class models by reducing baseline and background shifts. Smoothing of raw spectra led to inferior identification performance and proved itself to be unsuitable because some of the detailed frequency details were lost during smoothing. The best model performance was obtained with second derivative spectra by SIMCA (sensitivity 0.905 and specificity 0.944) and PLSCM (sensitivity 0.952 and specificity 0.937). Although it is difficult to perform an exhaustive sampling of all types of pure sesame oils and potential adulterations, PLS and SIMCA combined with FTIR spectrometry can detect most of current adulterations of sesame oils on the Chinese market.

Are algal oils realistic options for biofuels?

Are algal oils realistic options for biofuels?

Bariatrics, Metabolic Dysfunction and the Surgeon

Life expectancy has increased over the course of the preceding century. The phenomenon of epidemiological transition reflects the fact that there has been a shift in the major causes of death and disability from communicable, maternal and perinatal causes to chronic, non- communicable ones. The nutritional transition is being witnessed today on a global scale. As a country develops and more people buy processed food rather than growing and buying raw ingredients, an increasing proportion of calories tend to be drawn from sugars added to manufacture food and from relatively cheap oils. Alongside the change in diet, changes in food products and the technology of work and leisure lead to decreases in physical exercise. The consequent epidemic of diet related non-communicable diseases (obesity, diabetes, hypertension and CVD) co-exists with residual under nutrition and is projected to increase rapidly. For example, in India and China a shift in diet towards higher fat and lower carbohydrate is resulting in rapid increases in overweight among all adults in China and mainly among urban residents and high income rural residents in India. Countries which have completed the transition to over nutrition are experiencing a continual increase in levels of obesity, as high fat, high sugar diet and low exercise permeate society.

Potential Use of FTIR-ATR Spectroscopic Method for Determination of Virgin Coconut Oil and Extra Virgin Olive Oil in Ternary Mixture Systems

The aim of this study was to investigate the feasibility of Fourier-transform infrared (FTIR) spectroscopy combined with multivariate calibrations of partial least square (PLS) and principle component regression (PCR) for analysis of virgin coconut oil (VCO) in the ternary mixture with palm oil (PO) and olive oil, and for analysis of extra virgin olive oil (EVOO) mixed with soybean oil (SO) and corn oil (CO). The spectra of individual oils and their blends with certain concentrations were scanned using horizontal attenuated total reflectance accessory at mid-infrared region of 4,000–650 cm−1. The optimal frequency regions selected for calibration models were based on its ability to give the highest values of coefficient of determination (R 2) and the lowest values of root mean standard error of calibration (RMSEC). PLS was slightly better for quantitative analysis of VCO and EVOO compared with PCR. VCO in ternary mixtures is successfully determined at frequency region of 1,200–1,000 using second derivative FTIR spectra with R 2 and RMSEC values of 0.999 and 0.200, respectively. Meanwhile, EVOO is best determined at 1,200–1,000 using first derivative FTIR spectra with R 2 and RMSEC values of 0.999 and 0.975, respectively. The results showed that FTIR spectroscopy offers accurate and reliable technique for quantitative analysis of VCO and EVOO in ternary systems. In addition, the developed method can be used for the monitoring of VCO and EVOO adulteration with cheaper oils like PO in VCO as well as SO and CO in EVOO.

Determination of Olive Oil Adulteration with Vegetable Oils by near Infrared Spectroscopy Coupled with Multivariate Calibration

There has been growing public awareness about the health benefits of olive oil throughout the world in recent years, resulting in a significant increase in its consumption as part of the daily diet. This demand has attracted fraudulent attempts to market olive oil which has been adulterated with cheaper oils. This study focuses on the near infrared (NIR) spectroscopic determination of adulteration of olive oil by vegetable oils using multivariate calibration. The binary, ternary and quaternary mixtures of olive, soybean, cotton, corn, canola and sunflower oils were prepared using a random design. The absorbance spectra of these synthetic samples were measured by a near infrared (NIR) spectrometer. A genetic algorithm-based variable selection algorithm, coupled with an inverse least squares multivariate calibration method (GILS) was used to build calibration models for possible adulterants and olive oil in the adulterated mixtures. The correlation coefficients of actual versus predicted concentrations resulting from multivariate calibration models for the different oils were between 0.90 and 0.99. The results demonstrated that NIR spectroscopy in conjunction with the GILS method makes it possible to determine the adulteration of olive oils regardless of adulterant vegetable oils over a wide range of concentrations.

MONITORING OF VIRGIN COCONUT OIL (VCO) ADULTERATION WITH PALM OIL USING FOURIER TRANSFORM INFRARED SPECTROSCOPY

ABSTRACT Virgin coconut oil (VCO) may be adulterated with cheaper oils, such as palm oil (PO). Thus, the detection and quantification of VCO adulteration with PO was monitored using Fourier transform infrared (FTIR) spectroscopy, combined with chemometrics of partial least square (PLS) and discriminant analysis at frequency regions of 3,010–3,000, 1,660–1,650 and 1,120–1,105/cm. Attenuated total reflectance (ATR) measurements were made on pure VCO and that adulterated with varying concentrations of PO (0.5–50% w/w in VCO). PLS calibration exhibited a good relationship between actual and FTIR‐predicted values with coefficient of determination (R2) of 0.999 and standard error of calibration of 0.533. The cross validation was performed by removing one standard at a time, and the final R2 value of 0.996 and standard error of prediction of 0.953 were obtained. The discriminant analysis using seven principal components was able to classify pure VCO and that adulterated with PO.PRACTICAL APPLICATIONSThe adulteration of virgin coconut oil (VCO) with cheaper oils is a serious matter, not only for food suppliers but also for consumers. Therefore, an analytical technique offering fast and reliable detection of such adulteration must be developed. Fourier transform infrared spectroscopy combined with chemometrics of partial least square for quantitative analysis of adulterant, and discriminant analysis for classification between VCO and that adulterated with palm oil, can be employed for detection of palm oil as an adulterant in VCO for quality assurance purposes.

DIFFERENTIAL SCANNING CALORIMETRY DETECTION OF HIGH OLEIC SUNFLOWER OIL AS AN ADULTERANT IN EXTRA‐VIRGIN OLIVE OIL

ABSTRACT Differential scanning calorimetry (DSC) was employed to detect high oleic sunflower oil (HOSo) as an adulterant in extra‐virgin olive oil (EVOo) by means of cooling and heating thermograms. Addition of HOSo did not significantly alter cooling profiles of EVOo except for onset temperature of crystallization, which was significantly shifted toward lower temperature at 40% of adulterant addition. At the same percentage of adulteration, the heating profile of EVOo was significantly changed as the major endotherm broadened and the minor event became smaller and less evident. Cooling thermograms of pure oils and their admixtures were deconvoluted into three constituent exothermic peaks in an attempt to detect addition of HOSo at levels lower than 40%. Thermal properties of the two lower‐temperature exotherms (area percentage, offset temperature and range of transition) were significantly changed at≥20% of HOSo substitution, suggesting that DSC can be employed to detect this oil as an EVOo adulterant.PRACTICAL APPLICATIONSAdulteration of extra‐virgin olive oil (EVOo) with cheaper oils from other vegetable sources or seeds, as well as with lower quality olive oils, is a serious concern for oil suppliers and consumers and requires the use of new analytical techniques for their detection. Differential scanning calorimetry (DSC) exhibits some advantages over the classical analytical methods as it does not require sample preparation and use of solvents, thus resulting in a reduced environmental impact. Results suggested that its application to the detection of EVOo adulteration with high oleic sunflower oil, a vegetable oil largely employed for this type of fraud, is promising with the support of the deconvolution analysis of cooling thermograms.

Detection of Adulteration in Iranian Olive Oils Using Instrumental (GC, NMR, DSC) Methods

AbstractThis paper describes an investigation into the usefulness of some instrumental methods (GC, NMR, and DSC) in the detection of adulteration of olive oil with soybean, sunflower, and canola oils (that are relatively cheap oils mixed as adulterants with olive oil). These seed oils were compared with genuine and commercial olive oils, two of which appeared to have been adulterated. It was observed that from among physical and chemical indices, the iodine value and the refractive index in the two olive oil samples (named A and B) were significantly higher (P < 0.01) than in the reference (genuine) olive oil, both values being above standard limits established for olive oil. On the other hand, fatty acid (FA) profiles in these two samples exhibited higher amounts of linolenic and linoleic acids (5.34 and 39.92%, 6.38 and 54.42%, 0.79 and 12.88% for A, B and genuine olive oils respectively) but significantly lower amounts of oleic acid (30.07, 21.72 and 67.86%, respectively). The number and intensity of signals observed using 1H NMR indicated that the peaks numbered 2 and 7 were useful in the determination of olive oil purity. Because of higher linolenic and linoleic acid contents in samples A and B, the intensity and integrated areas for these two signals were higher than those for other olive oil samples in which signal 2 was not observed and signal 7 had a very low intensity. Satisfactory results were achieved from quantitation of DSC parameters. The results show that due to increased unsaturated FAs in samples A and B and the consequent changes in triacylglycerol profiles, offset crystallization temperature and onset melting temperature in these two olive oils differed from those of the reference and clearly shifted to lower values. Crystallization and melting curves were similar to the corresponding curves observed for soybean and sunflower oils in terms of shape and number of peaks.

Microbial and algal oils: Do they have a future for biodiesel or as commodity oils?

AbstractWe review the prospects of using yeasts and microalgae as sources of cheap oils that could be used for biodiesel. We conclude that yeast oils, the cheapest of the oils producible by heterotrophic microorganisms, are too expensive to be viable alternatives to the major commodity plant oils. Algal oils are similarly unlikely to be economic; the cheapest form of cultivation is in open ponds which then requires a robust, fast‐growing alga that can withstand adventitious predatory protozoa or contaminating bacteria and, at the same time, attain an oil content of at least 40% of the biomass. No such alga has yet been identified. However, we note that if the prices of the major plant oils and crude oil continue to rise in the future, as they have done over the past 12 months, then algal lipids might just become a realistic alternative within the next 10 to 15 years. Better prospects would, however, be to focus on algae as sources of polyunsaturated fatty acids.

Rapid detection of olive–pomace oil adulteration in extra virgin olive oils from the protected denomination of origin “Siurana” using excitation–emission fluorescence spectroscopy and three-way methods of analysis

Extra virgin olive oil (EVOO) is the highest-quality type of olive oil. This makes it also the most expensive. For this reason, it is sometimes adulterated with cheaper oils. One of these is olive–pomace oil (OPO). The protected denomination of origin (PDO) “Siurana” distinction is given to the EVOO produced in a specific area of the south of Catalonia. Here we study the potential of excitation–emission fluorescence spectroscopy (EEFS) and three-way methods of analysis to detect OPO adulteration in PDO “Siurana” olive oils at low levels (5%). First, we apply unfold principal component analysis (unfold-PCA) and parallel factor analysis (PARAFAC) for exploratory analysis. Then, we use the Hotelling T 2 and Q statistics as a fast screening method for detecting adulteration. We show that discrimination between non-adulterated and adulterated samples can be improved using Fisher's linear discriminant analysis (LDA) and discriminant multi-way partial least squares (N-PLS) regression, the latter giving a 100% of correct classification. Finally, we quantify the level of adulteration using N-PLS.

Lipase Mediated Upgradation of Dietary Fats and Oils

ABSTRACT In the present scenario, fats and oil modification is one of the prime areas in food processing industry that demands novel economic and green technologies. In this respect, tailored vegetable oils with nutritionally important structured triacylglycerols and altered physicochemical properties have a big potential in the future market. In this context, it is well established that lipases especially microbial lipases, which are regiospecific and fatty acid specific, are of immense importance and hence could be exploited for retailoring of vegetable oils. Further, of the bulk available, cheap oils could also be upgraded to synthesize nutritionally important structured triacylglycerols like cocoa butter substitutes, low calorie triacylglycerols, PUFA-enriched and oleic acid enriched oils. It is also possible to change the physical properties of natural oils to convert them into margarines and hard butter with higher melting points or into special low calorie spreads with short or medium chain fatty acids. Today, by and large, fat and oil modifications are carried out chemically following the method of directed inter-esterification. The process is energy intensive and non-specific. Lipase mediated modifications are likely to occupy a prominent place in oil industry for tailoring structured lipids since enzymatic modifications are specific and can be carried out at moderate reaction conditions. However, as a commercial venture, lipases are yet to be fully exploited. Once the technologies are established, the demand of lipases in oil industry is expected to increase tremendously in the near future for specific modifications of fats and oils to meet the changing consumers' dietary requirements.

Comparison of near‐infrared, fourier transform‐infrared, and fourier transform‐raman methods for determining olive pomace oil adulteration in extra virgin olive oil

AbstractThe adulteration of extra virgin olive oil with cheaper oils is a major problem in the olive oil market. In this study, near‐infrared, mid‐infrared, and Raman spectroscopic techniques were used to quantify the amount of olive pomace oil adulteration in extra virgin olive oil. The concentration of olive pomace oil in extra virgin olive oil was in the range between 0 and 100% in 5% increments by weight. Of the methods studied, Fourier transform‐Raman spectroscopy gave the highest correlation with a correlation coefficient of 0.997 and a standard error of prediction of 1.72%. The spectroscopic techniques have the potential to become a tool for rapid determination of adulteration in extra virgin olive oil, because they are casy to use and cost‐effective.

Reviewing 1998, looking beyond

1998 will be remembered as a year when the price of oil headed south. In inflation-adjusted dollars, we saw the cheapest oil ever. According to the financial pundits, prices are unlikely to rise for some time and perhaps not at all in 1999. (This may or may not be true. The same pundits, early last year, predicted good oil prices for most of 1998.)

Improved analysis of fatty acid anilides: application to toxic and to aniline and citric acid-containing oils.

The Spanish Toxic Oil Syndrome (TOS) was traced to the consumption of some cheap oils sold at retail by street salesmen (Tabuenca 1981; Kilbourne et al. 1992). These oils contained different proportions of a refined batch of rapeseed oil initially denatured with 2% of aniline and imported from France for industrial use (Tabuenca 1981). However, although most of the free aniline was effectively extracted during the refining processes, a significant part of it reacted with fatty acids yielding the corresponding fatty acid anilides (FAAs) (Guitart and Gelpi 1992). Although toxicological data on FAAs are very controversial, they had been proposed as the causative agents of the illness or, at least, are considered as the best markers of toxic oils (Bernert Jr. et al. 1987; Kilbourne et al. 1991). Four gas chromatographic methods have been published for the analysis of FAAs in oils (Diachenko et al. 1982; Vazquez Roncero et al. 1983; Artigas et al. 1983; Balley et al. 1983). The chemical similarity with the methyl esters of fatty acids makes gas-liquid chromatography (GLC) the method of choice for the analysis of FAAs, although their higher molecular weights limited up to now the use of the more resolutive polar stationary phases. Since the introduction of cross-bonded polar phases which can be run at higher temperatures than columns available in the last decade, the possibility to obtain a better separation of FAAs is raised. This paper reports the development of such a method and its application to 10 case oil samples and to the study of the generation rate of FAAs in aniline-denatured rapeseed oils containing citric acid. This additive was used in some refineries that handled the TOS-suspected oils in 1981 as a stabilizer, preservative and antioxidant, and was added normally before the deodorizing process at a l-2% concentration (Special Investigation Team 1981).

A review of factors influencing control strategies against tomato leaf curl virus disease in the Sudan

Abstract Tomato leaf curl virus (TLCV) causes a major disease in the Sudan and 75% losses in yield have been recorded. No resistant varieties are available to farmers and so other control measures have to be used. The only vector of the virus is the whitefly, Bemisia tabaci and it is the female which is largely responsible for transmission. Insecticides have been used to control the whitefly in Sudan but, for reasons of safety and economy, they were substituted by mineral oils. Promising results have been obtained using the easily available cheap oils from the area. The vector reproduces on a wide range of plant species, many of which are also hosts for the virus. However some crops which are good hosts of the vector but not the virus, when interplanted with tomato may attract the vector and so reduce virus attack. Although this reduces the effective area under tomatoes there are benefits gained from the interplanted crop and the increase in yield potential of each crop.

The Political Significance of Tropical Vegetable Fats for the Industrial Countries of Europe

In the first decades of the nineteenth century a decided change occurred in the economic structure of central and western Europe. The continent had just recovered from the Napoleonic Wars; the industrial revolution was spreading from England to the continent and the population of western and central Europe was rapidly increasing. With industrialization there also came from England the system of crop rotation which destroyed the old three-field economy and made possible the cultivation of potatoes on the formerly fallow lands. By this means starch flour became an important constituent in the diet. However, there soon appeared an acute shortage of animal fats, especially since the animal fats of the Arctic, particularly whale oil, were quickly depleted. Under these circumstances it was natural that industrial Europe should turn more and more to reliance upon the abundant and cheap vegetable fats and oils of the tropics. Each of the three tropical regions has its own indigenous fat plant, as it has also its characteristic cereal and luxury plant. In tropical Asia the coconut palm is the most important fat plant, and in tropical Africa the oil palm (Elaeis guineensis). The outstanding producer of fat native to tropical America is not a palm but an annual plant, the peanut (Arachis hypogaea). Tropical America has never played an important world r6le in the production of fats for export. The American peanut is not grown in America for the European market but in Africa and Asia. This fact has nothing to do with the soil or climate but is historically induced. In tropical America the Europeans with the help of Negro slaves had established the; plantation industry which, because of great expenditure of labor and capital, was profitable only if products of high value were cultivated. Under these conditions the commercial cultivation of the peanut did not pay.