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Free fatty acids (FFAs) are derived from the undesired hydrolysis reaction of glycerides with the presence of lipase, and quantified as acid value for crude palm oil (CPO) grading. Since FFA content is directly proportional to time, duration from harvest to sterilization of fruits is not more than a day. This paper reports peculiar trend of FFA formation over time when the analysis of FFA was carried out differently. Analysis results of FFA and glyceride contents by timely picking the fruitlets (R-fruit) from fresh fruit bunch (FFB) were compared with the fruitlets from spikelet (S-fruit) that were initially removed all for 7 days. The results showed that the increment of FFA content of the latter was 10 hour faster. This implies that the fruitlets from spikelet resemble the detached fruits which having higher rate of FFA formation compared to the fruitlets that attached to FFB. By using SigmaPlot, the graphs of R-fruit and S-fruit were best fitted into damped sine, 5 parameter with linear and rational with 4 parameters respectively. Nevertheless, lower R2 value was obtained for the fruitlets from readily-removed spikelet compared to the fruitlets from FFB, indicating that other factors might have also affected the formation of FFA.

Nitro-fatty acids (NO 2 -FA) are pleiotropic modulators of redox signaling pathways. Their effects on inflammatory signaling have been studied in great detail in cell, animal and clinical models primarily using exogenously administered nitro-oleic acid. While we know a considerable amount regarding NO 2 -FA signaling, endogenous formation and metabolism is relatively unexplored. This review will cover what is currently known regarding the proposed mechanisms of NO 2 -FA formation, dietary modulation of endogenous NO 2 -FA levels, pathways of NO 2 -FA metabolism and the detection of NO 2 -FA and corresponding metabolites. Fil: Buchan, Gregory J.. University of Pittsburgh; Estados Unidos Fil: Bonacci, Gustavo Roberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Centro de Investigaciones en Bioquímica Clínica e Inmunología; Argentina Fil: Fazzari, Marco. University of Pittsburgh; Estados Unidos. Fondazione Ri.Med; Italia Fil: Salvatore, Sonia Rosana. University of Pittsburgh; Estados Unidos Fil: Gelhaus Wendell, Stacy. University of Pittsburgh; Estados Unidos

Blueberry, defatted grape seed powder and defatted poppy seeds were incorporated into biscuits at a level of 5%. Some physicochemical and sensory characteristics were evaluated during 5 months storage period. Diameter, a* (−a = greenness, +a = redness) values, ash, fat, crude fiber, Mg and Ca contents increased, while L* (lightness), b* (−b = blueness, +b = yellowness) values decreased significantly (P

Processing contaminants may be defined as substances that are produced in a food when it is cooked or processed, are not present or are present at much lower concentrations in the raw, unprocessed food, and are undesirable either because they have an adverse effect on product quality or because they are potentially harmful. The presence of very low levels of processing contaminants in common foods is becoming an increasingly important issue for the food industry, as developments in analytical techniques and equipment bring foods under closer and closer scrutiny. This review considers the formation of lipid oxidation products, hydrogenation of polyunsaturated fatty acids to prevent lipid oxidation and the associated risk of trans fatty acid formation. The formation of acrylamide in the Maillard reaction is described, as well as the genetic and agronomic approaches being taken to reduce the acrylamide-forming potential of cereal grain. The multiple routes for the formation of furan and associated chemicals, including hydroxymethylfurfuryl, are also described. The evolving regulatory and public perception situations for these processing contaminants and their implications for the cereal supply chain are discussed, emphasising the need for cereal breeders to engage with the contaminants issue., Highlights • Processing contaminants defined. • Trans fat, acrylamide, furan and hydroxymethylfurfuryl formation described in detail. • Genetic and agronomic approaches to reducing the potential for contaminant formation described. • Evolving regulatory situation reviewed. • Breeders urged to engage on the issue of processing contaminants.

This study was conducted to investigate the possible formation of trans fatty acids due to gamma-irradiation of ground beef and liquid egg via a radical path. The effects of irradiation on trans fatty acids in ground beef and liquid egg were evaluated by GC analysis. The control sample of ground beef had higher concentrations of total trans fatty acids than the liquid egg. C18:1-11t was the major trans fatty acid detected in non-irradiated ground beef. The results showed that irradiation led to a significant increase of total trans fatty acid content in both of the two food items with an absorbed dose range between 6.743 and 11.472 kGy (P < 0.05). The change in C18:1-9t content was the most significant compared with other trans fatty acids. Additionally, gamma-irradiation caused a higher rate of trans fatty acid formation in liquid egg compared with ground beef. However, a slight decrease in the total trans fatty acid amount was observed in ground beef with an absorbed dose at 21.113 kGy. The increase in trans fatty acid content was negligible in liquid egg under the same absorbed dose. This result may be due to the oxidation of unsaturated configurations of both cis and trans fatty acids.

To evaluate the effects of repeated deep-frying on the trans-fatty acid (TFA) formation in soybean oils, simultaneous frying experiments were carried out. French fries were prepared using three different types of soybean oil (pressed soybean oil, PSBO; first-grade solvent extracted soybean oil, FG-SESBO; and third-grade solvent extracted soybean oil, TG-SESBO). French fries were fried intermittently at 180–185°C for a total frying time of 32 h and at an interval time of 30 min. It was found that the initial amount of total TFAs was 0.29 g/100 g, 0.31 g/100 g, and 0.90 g/100 g in PSBO, TG-SESBO, and FG-SESBO, respectively. Before the frying started, the C18:1,t-9, trans-linoleic acid (TLA), trans-linolenic acid (TLNA), and total TFA content of the PSBO and TG-SESBO were significantly lower than in the FG-SESBO (p

Short-chain fatty acids (SCFA) are considered to have important physiological functions. However, to prove this, SCFA must be determined, which is rather difficult as a lot of factors interfere with their production. This review focuses on the factors that influence the prediction of short-chain fatty acid formation in the large intestine of monogastric mammals. To mimic the in vivo situation, when predicting the amount of short-chain fatty acids produced from a certain substrate based on in vitro models, one has to estimate the amount of this substrate entering the large intestine, the retention time in the different parts of the large intestine, and the substrate fermentability. Instead of in vitro models, direct and indirect techniques may be used to measure short-chain fatty acid production in vivo. Direct techniques include the measurement of input and output or measuring differences in SCFA between portal and venous blood whereas indirect techniques measure the end products of fermentation. In this case, other factors have to be taken into account, including technical limitations and ethical considerations. In this review it is concluded that the choice for a method will rely on the purpose of the study taking into account the (dis)advantages of every method.

To evaluate the effect of carrot on the quality improvement of the sweet syrupy cheese ball known as Rasgulla, six types of Rasgulla samples containing carrot paste in the proportions of 0, 10, 20, 30, 40 and 50% were prepared and stored in closed containers at 25°C for 40 h. With increasing storage time the acidity of syrup, free fatty acid formation, absorptivity value and colour of all Rasgulla samples increased. The addition of carrot to chhana (analogous to cottage cheese) decreased acid and free fatty acid formation in Rasgulla syrup, decreased absorptivity, and also gave colour stability. Carrot concentration up to 30% improves the quality of Rasgulla. More than a 30% concentration of carrot reduced the oxidative stability of Rasgulla, while a more than 40% carrot concentration reduced its colour stability. Thus, the use of carrot up a concentration of 30% is suggested to increase the oxidative stability as well as the colour stability of Rasgulla.

Cetyl alcohol has been submitted to the Guerbet reaction and converted into 2-tetradecyl-octadecyl alcohol. Conditions have been found whereby this branched-chain alcohol can be obtained in good yield with virtual suppression of fatty acid formation. Some reactions and derivatives of the new alcohol are described and some light thrown on the mechanism of the Guerbet reaction. The modified reaction described has also been applied to sperm oil alcohols.

Hydrogenated oil has been widely used for production of shortenings or margarine, however, the presence of trans fatty acids may be detrimental to human health. The objectives of this study were to develop an improved method for analysis of trans fatty acids and evaluate their formation in both unhydrogenated and hydrogenated soybean oil during heating at 160, 180 and 200 °C for varied length of time. Results showed that among the four columns tested, an Agilent HP-88 column (100 × 0.25 mm I.D., 0.2-μm film thickness) could resolve eight trans fatty acids and nine cis fatty acids simultaneously within 31 min with injector temperature 240 °C, detector temperature 250 °C, and column temperature 170 °C in the beginning, maintained for 24 min, increased to 220 °C at 7.5 °C/min, 230 °C at 10 °C/min, and maintained for 5 min. The contents of both cis and trans fatty acids showed a decreased trend for the increase of heating time or temperature. No trans fatty acid formation was observed even after extensive heating of unhydrogenated and hydrogenated soybean oil for 24 h. This phenomenon demonstrated that trans fatty acids can only be formed under severe conditions.

A laboratory scale model reactor was used to investigate volatile fatty acid (VFA) formation during anaerobic degradation in an anaerobic hybrid reactor. The purpose of the study was to determine the role of upflow anaerobic sludge blanket (UASB) and anaerobic filter (AF) regions of the hybrid reactor on bio-degradation of organic compounds using VFA as an operational parameter. Acetic, propionic, butyric, and valeric acid concentrations of samples taken from the reactor effluent, fixed bed region and the upper part of the sludge bed region were analysed. VFA formation was monitored at two phases. In phase-I, 10kg COD m(-3) per day organic loading rate (OLR) (C-o = 10,000 mg COD l(-1) and theta(H) = 1 day) and in phase-II 7.6kg COD m(-3) per day OLR (C-o = 15,000 mg COD l(-1) and theta(H) = 2 days) was applied. The average acetic acid concentrations of the upper end of the reactor and sludge bed region were 150 and 354.9 mg l(-1), respectively. These results showed that VIA concentrations increase from the top to the bottom of the reactor, indicating higher methanogenic activity in the upper part and higher acetogenic activity in the bottom of the reactor. pH measurements confirmed this result. (C) 2003 Elsevier Ltd. All rights reserved.

Karaman, Safa/0000-0002-1865-661X; DOGAN, Mahmut/0000-0003-1639-4641; Toker, Omer Said/0000-0002-7304-2071 WOS:000346850400010 The present study investigates fatty acid composition and trans fatty acid formation in oils extracted from French-fried potatoes, which were produced in the laboratory and collected from different restaurants. Potatoes were fried at 180 degrees C at different frying periods (1, 7, 13, 19, 25, and 31 min) and the fatty acid composition of the extracted oils was determined. Principal component analysis and hierarchical cluster analysis were used to characterize and classify the samples. Four major fatty acids were identified in the samples, namely palmitic acid, stearic acid, oleic acid, and linoleic acid. Linolelaidic acid (C18:2 trans) was detected in the oil samples extracted from potatoes fried in margarine. Three principal components (PCs) and 4 main clusters were obtained from the chemometric analysis, which characterized the samples. Three PCs were found to be explanatory of more than 84.96% of the total variability in the data set. Research Project Unit of Erciyes UniversityErciyes University [FBY09-1001] The authors would like to thank the Research Project Unit of Erciyes University for funding this study (Project Code: FBY09-1001).

Sensory and chemical analyses were performed during the chilled storage of whole and filleted horse mackerel (Trachurus trachurus), an underutilized medium-fat fish species. For both kinds of fish products, satisfactory correlations with the storage time were obtained for amine formation (total volatile basenitrogen and trimethylamine-nitrogen), lipid damage (free fatty acid formation), and formation of interaction compounds (fluorescence detection in the aqueous phase). Sensory analyses showed a gradual lower grading with time, with a shelf life of 14 d for whole-fish samples and 12 d for fillet samples. Correlation and multivariate analyses between the sensory attributes and the chemical indices showed that trimethylamine-nitrogen detection was the most accurate chemical method for damage assessment during the chilled storage of whole and filleted horse mackerel.

Olive oil (blend of refined and virgin) and sunflower oil containing added methanol phenolic extracts of dry rosemary and olive vegetable water or the synthetic antioxidant BHA in combination with the extracts, were used in a frying process. Eight frying operations were performed at 180 °C with 24 hr intervals between fryings. During the frying period the trans fatty acids (TFA) by capillary column gas chromatography (CC-GC) were determined. Trans fatty acids of oleic and linoleic were increased with frying time in both the control oil samples. The rosemary additives (extracts) alone and in combination with BHA decreased the level of trans fatty acids (mainly elaidic acid), while the addition of olive vegetable water did not have any effect.Aceite de oliva (mezcla de virgen y refinado) y aceite de girasol con extractos fenólicos de romero seco y aguas de vegetación de aceituna, o con el antioxidante sintético BHA en combinación con los extractos, se usaron en proceso de fritura. Se realizaron 8 operaciones de fritura a 180°C con intervalos de 24 h. Se determinaron los ácidos grasos trans (TFA) por cromatografía de gases en columna capilar (CC-GC). Los ácidos grasos trans de oleico y linoleico aumentaron con el tiempo de fritura en las muestras de aceite control. Los extractos de romero, solos y en combinación con BHA, disminuyeron los niveles de ácidos grasos trans (principalmente ácido elaídico) mientras que la adicción de aguas de vegetación de aceituna no tuvo ningún efecto.

Anchovy were stored at 17°C, 8°C, 0°C and −6°C. Samples were withdrawn periodically and the extracted lipids analysed for free fatty acids (FFA) and phosphorus (P) content. From the results of these analyses it was possible to calculate the rates of enzymatic hydrolysis of the phospholipids and the neutral lipids. Phospholipids hydrolysed much faster than neutral lipids at the four temperatures. An Arrhenius plot showed that at about –29°C the two rates were identical. Der Gehalt an freien Fettsauren in Fischol, Teil IV: Geschwindigkeiten zur Bildung von freien Fettsauren aus Phospholipiden und Neutrallipiden im bei verschiedenen Temperaturen gelagerten Anchovis (Engraulis capensis) Der Anchovis wurde bei 17°C, 8°C, 0°C und –6°C gelagert. Es wurden in regelmasigen Zeitabstanden Proben entnommen und bezuglich ihres Gehalts an freien Fettsauren und Phosphor analysiert. Die Ergebnisse dieser Analysen ermoglichten die Berechnung der Geschwindigkeiten der enzymatischen Hydrolyse von Phospholipiden und Neutrallipiden. Phospholipide hydrolysierten erheblich schneller als Neutrallipide bei den vier Temperaturen. Die Arrhenius-Darstellung ergab, das bei ungefahr –29°C beide Geschwindigkeiten identisch waren.

The presence of free fatty acid (FFA) is an important factor in determining rice quality for brewing. FFA formation in milled rice during storage was monitored, and a two-parameter semiempirical kinetic model giving product concentration as a function of time is proposed to describe FFA formation on milled rice during storage. The model was tested using sets of data obtained from partially milled rice samples stored at 24, 37, and 50 °C and fully milled rice stored at 37 °C and 70% relative humidity. The predicted values provide very good fits (R 2 ≥ 97%) of the experimental data at all storage temperatures. A two-substrate reaction mechanism representing a two-phase process is also presented. Milled rice FFA at a given storage time varied with storage temperatures. The kinetic model and mechanisms proposed could be useful in describing and predicting FFA contents of milled rice during storage and transportation. Keywords: Free fatty acid; milled rice; kinetics; mechanisms

10 páginas, 3 tablas, 2 figuras.-- The final publication is available at www.springerlink.com, A packaging system combining a polyphenolrich film and vacuum (PPRF–VP) was applied to farmed coho salmon (Oncorhynchus kisutch) muscle for an 18- month storage (−18 °C). For it, two different concentrations of polyphenol compounds (namely, p-coumaric and ferulic acids) obtained from a barley husk extract were applied (PPRF–VP conditions) and compared to vacuum packaging without polyphenol presence (vacuum control; VP condition) and to packaging in the absence of vacuum and polyphenols (control; CP condition). The study was addressed to lipid hydrolysis and oxidation development and to lipid changes related to nutritional value. Both PPRF–VP conditions provided an inhibitory effect (p< 0.05) on conjugated diene and fluorescent compound formation in frozen salmon. Compared to CP condition, vacuum packaging (PPRF–VP and VP conditions) led to lower (p0.05) of polyphenol presence and vacuum packaging could be inferred on free fatty acid formation (hydrolysis development) and on polyunsaturated fatty acid retention (polyene index assessment). A low rancid odour development was observed in all kinds of fish samples, this being lower (p

Extra-cold storage (-30 and -40 o C) of mackerel (Scomber scombrus) mince and fillets showed lower free fatty acid formation. Extra-cold storage (-30 o C) of white hake (Urophycis tenuis) fillets produced fish with better quality based on sensory and chemical indices. The colder the storage temperature, the less firrm the hake mince and fillets. Ascorbic acid accelerated cohesiveness development of mackerel mince and fillets. Over time, the quality of the hake and mackerel decreased according to sensory and chemical indices. They became tougher and generally more cohesive

Long-term storage of fish oils frequently leads to deterioration in quality due to enzymatic formation of free fatty acids (FFA). The present investigation has identified a number of chemical characteristics which can serve as indices in predicting which oils are liable to show FFA escalation on storage. It also outlines measures to be taken to prevent FFA escalation. Der Gehalt an freien Fettsauren in Fischol III: Einflus verschiedener Variablen auf die Bildung von freien Fettsauren wahrend der Lagerung von Anchovis-Ol bei 25°C Die lange Lagerung von Fischolen fuhrt oftmals zur Verschlechterung der Qualitat wegen enzymatischer Bildung von freien Fettsauren. In der vorliegenden Arbeit wurde eine Anzahl chemischer Daten ermittelt, die als Merkmal fur eine Voraussage dienen konnen, bei welchen Olen die Lagerung zu einem starken Anstieg der freien Fettsauren fuhrt. Es werden auch Masnahmen zur Verhinderung des Anstiegs der freien Fettsauren aufgezeigt.

3 pages, 2 tables., Coho salmon (Oncorhynchus kisutch) has recently attracted a great interest as a farmed product. This research focuses on its commercialisation as a chilled product. Thus, the effect of a previous hydrostatic high pressure (HHP) treatment on chemical changes related to quality loss was studied. A marked effect of HHP treatment was observed on lipid hydrolysis (free fatty acid formation), lipid oxidation (primary, secondary and tertiary compounds) and protein breakdown (sarcoplasmic fraction) throughout the chilling storage; however, no influence could be observed on nucleotide degradation and polyene index. Sensory analysis (putrid and amine odour development) showed a profitable effect of HHP on chilled salmon quality; however, no effect could be concluded on rancid odour development.

No Abstract. Nigerian Journal of Chemical Research Vol. 1 1996: 8-12

▪ Recent studies indicate that fatty acids are formed in significant concentrations during the composting of organic household residuals. Their presence may be one major reason for depressed germination and seedling development that often result following application of compost. Experimental results in Sweden indicate that at least five to six months should elapse before low levels of fatty acids for cropping are reached in the composts. Further research on fatty acid formation is recommended.

A high intake of trans fatty acids in children may be disadvantageous because of untoward effects on lipoprotein metabolism and a possible impairment of arachidonic acid synthesis. We measured the trans fatty acid content of different brands of spreads and cold cuts typically consumed by German children because these foods may contribute a considerable portion of total trans fatty acid intake. The highest trans fatty acid contents were found in regular margarines (4.5, 0.0–10.6; median %-wt/wt of fatty acids, minimal-maximal), chocolate spreads (5.5, 0.7–11.1), butter (4.7, 3.7–5.2) and cheese (3.6, 1.8–4.0), while lower values were present in diet margarines (0.2, 0.0–0.4), vegetarian spreads (0.2, 0.1–0.4), peanut butter (0.0, 0.0–0.3) and sausages (1.7, 0.6–6.4). Calculations of typical dietary plans for young children show that food selection and variations in trans fatt acid contents may lead to marked differences in daily trans intake of >100 % (3.1 g/d vs. 1.5 g/d). We propose that trans fatty acid content should be declared on labels of fatty food products to enable the consumer to choose, and further attempts should be made to lower trans fatty acid formation during technical hydrogenation.

Publisher Summary Hydrogenation is the process of treating fats and oils with hydrogen gas in the presence of a catalyst. The result is the conversion of liquid oils to fluid, semi-solid, or plastic fats suitable for use in any edible oil application. The reaction proceeds when oil, hydrogen gas, and the catalyst are brought together under appropriate agitation and temperature conditions. This chapter discusses the benefits of optimizing hydrogenation as a unit process, offering a processor the operational flexibility and efficiency required to remain competitive in value-added markets. Increases in different hydrogenation conditions affect the reaction selectivity, rate, and trans fatty acid formation. It is the proper management of the parameters that allows the processor maximum flexibility in producing any edible oil product. Therefore, optimum operational efficiency is achieved with the development and use of a base stock program.

A rapid, sensitive method is described for quantitative determination of lipase activity in rice bran. The method, using 4-methylumbelliferylheptanoate as a substrate for lipase activity, gave results that correlated with those obtained for lipase, as measured by free fatty acid formation, in trials to determine the conditions of heat treatment that are necessary for stabilization of rice bran against lipolytic hydrolysis.

SUMMARYCephalotyre (Ras) cheese slurries developed within 7 d of storage at 30 °C a flavour similar to that of conventional Ras cheese ripened for 2 months. Addition of a proteinase/lipase mixture, trace elements or Na citrate to fresh cheese slurries before storage at 30 °C enhanced flavour development. Additive-treated slurries showed after storage for 5 d at 30 °C a strong flavour similar to that of 3–4 months Ras cheese with increased protein degradation, acidity development, volatile fatty acid formation and higher bacterial counts. The effectiveness of the additives in enhancing flavour development and related chemical changes was in the order: proteinaseòlipase mixture > trace elements > Na citrate.

A fermentation balance equation was used to estimate the extent of fermentation of rations fed at or near voluntary intake to lactating dairy cows. The rations varied in hay to concentrate ratio from 100 :0 to 20 :80 and in four trials the high concentrate ration was fed completely pelleted. The extent of fermentation varied from 71% on the hay ration to 40% on the completely pelleted high concentrate ration. The factors affecting extent of fermentation were: 1) The hay to concentrate ratio, 2) fineness of particles, and 3) level of intake. The residual heat of fermentation was 6.4% of fermented substrate, and the theoretical CO 2 /CH 4 ratio increased with increasing concentrate in the diet. The assumptions involved in these computations and the implications of the results obtained on efficiency of fermentation and feed efficiency for ruminants were discussed.

It was found that the exposure of moist cottonseed to a radio frequency electric field for a period of from two to five minutes effectively reduced the formation of free fatty acids during subsequent storage of the seed. Two primary factors were involved in this action. First, moisture was rapidly removed from the seed and second, the enzymes responsible for free fatty acid formation were destroyed. Cottonseed containing 20% moisture accumulated free fatty acids only very slowly on storage at 38.5°C. after a brief dielectric heat treatment. The temperature inside the cottonseed was measured during the dielectric heat treatment. Temperature above 100°C. were attained in less than one minute.

Rainbow trout (Salmo gairdneri) muscle was stored in 5% MgSO4 in Ringer's solution, 15% dimethyl sulphoxide in Ringer's solution, and 6% dextran in 0.9% NaCl, at −10 C for periods of 2, 4, 8, and 12 weeks. The regular increase in free fatty acid (FFA) content was used as an index of muscle degradation. For the 12-week storage period at −10 C, the FFA content varied from 17.9 μmoles in fresh muscle to a maximum of 222 μmoles/100 g muscle for nonimmersed muscle. Samples immersed in MgSO4 solution alone showed a consistent statistically significant inhibition in FFA formation when compared with immersed and nonimmersed muscle controls. Immersion in DMSO produced the least visual deterioration in appearance, colour, and firmess of texture.

GROWTH hormone has been shown to affect both fatty acid formation (Welt and Wilhelmi, 1950; Brady, Lukens and Gurin, 1951) and oxidation (Greenbaum and McLean, 1953) but the significance of its role in these processes is not clear. Welt and Wilhelmi (1950) showed that growth hormone depressed the incorporation of deuterium labelled water into carcass and liver fats of rats. Brady, Lukens and Gurin (1951) noted that hypopltysectomy brought about an acceleration of fat formation from carbohydrate. These workers also demonstrated that the treatment of ‘Houssay’ cats with growth hormone inhibited lipogenesis. Greenbaum and McLean (1953) found that growth hormone mobilized fat in the liver and caused an increase in liver fatty acid oxidase. From findings of this sort it is generally considered that growth hormone has an inhibitory action on fat formation but apart from the demonstration by Welt and Wilhelmi (1950)

Refined sunflower oil was stored in brown and colorless glass bottles at ambient temperature (18–32°C) and 37°C to assess the effect of light, heat and air on the stability fo the oil and to record the progress of oxidative rancidity especially the secondary stages with respect to storage variation and time. Oil sample stored in brown color bottle was found to be superior (FFA 0.15 to 0.53; PV 0.5 to 80; HV 3 to 12; oxirane oxygen 0.2 to 2.3) over oil stored in colorless bottle (FFA 0.15 to 0.60; PV 0.5 to 91; HV 3 to 8; oxirane oxygen 0.1 to 2.8) at ambient temperature. Samples stored at 37°C deteriorated very fast. Silver nitrate test, oxidised fatty acid formation, urea adduct formation, picric acid-TLC test, Kreis test, DNP-TLC test, DNP-precipitation test have been devised to detect and follow oxidative rancidity. These tests worked well even at the lower levels of oxycompounds. No conjugation was detected in any of the oil.

We compared fatty acid formation in soybean ((L.) Merrill) seeds with a normal level and low level of chlorophyll. A low level of chlorophyll in the seed of four genotypes was obtained by covering nodes with aluminum foil before pods were visible. Seeds of known age were harvested from covered and uncovered nodes at 4-day intervals beginning 22 days after flowering and continuing until maturity. The percentage of palmitic, stearic, oleic, linoleic, and linolenic acid in the oil was determined by gas-liquid chromatography.Although fatty acid composition of the oil changed markedly during seed development, there were no large differences in the pattern of fatty acid formation among genotypes or between the covered and uncovered treatments. The similarity of linolenic acid percentage in seeds with a normal or low level of chlorophyll indicated that linolenic acid formation was not closely related to chlorophyll content in soybean seed.

Summary1. During alimentary lipemia and lipemia produced by intravenous injection of fat emulsions there was a rise in the concentration of free fatty acid in serum. The free fatty acid was found in the non-turbid portion of serum (infranatant of high speed centrifugation). Injection of heparin produced an elevation of free fatty acid concentration which was greater in lipemic than in fasting subjects. A portion of this elevation after heparin was attributable to in vitro lipolysis. 2. It is suggested that lipolysis with free fatty acid formation may play a role in normal fat metabolism and transport.

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The effect of water activity (aw) on rate of autoxidation of raw peanut oil at 37 C was studied. Up to 3 weeks of storage, no marked effect of aw on the rate of peroxide formation was noticeable. However, with prolonged storage, the rate of peroxide formation decreased rapidly at aw of 0.67 and higher as compared to aw of 0.50 and lower. At the end of 9 weeks’ storage, the peroxide value at aw=0.02-0.50 was in the range of 31–35, while it was only ca. 10 at 0.79 and 0.92 aw. There was no noticeable influence of aw on the rate of free fatty acid formation. The oil stored for 7 weeks at 0.02 and 0.11 aw had fresh flavor, although the peroxide values were high; whereas the oils at 0.79 and 0.92 aw were stale, although the peroxide values were less than 10. The anisidine value at 0.02 aw (348) was higher than at 0.92 aw (62). The carbonyl values at 0.02 and 0.11 aw were also higher (1090, 1021) than at 0.79 and 0.92 aw (573, 780). The results indicate that the protective effect on the oil against peroxide formation at high aw may be due to certain components present in raw peanut oil.