Cocoa butter substitutes from mango fat

Mango fat obtained by solvent extraction of the kernels of the mango fruit (Magnifera indica) has been studied for its suitability in making cocoa butter substitutes. The fat has been fractioned from acetone at low temperatures in one and/or two stages in order to segregate suitable solid fractions having physical properties closer to cocoa butter. The data pertaining to the solidification characteristics and dilatometric behavior of the mango fat, its acetone-fractionated products and their admixtures with cocoa butter in equal proportions have been determined in order to assess their compatibility with cocoa butter. Fractionated mango fat can serve as a good partial substitute for cocoa butter.     

Modification of Mango Kernel (Mangifera indica) Fat by Monoester-Polyester Interchange Reaction

Mango kernel fat containing 32–37% palmitic acid and 24–26% lauric acid can be prepared by monoester - polyester reaction with methyl esters of the corresponding fatty acids. The physical and chemical properties of interesterified products are found to be quite different from original mango fat. The modified mango fats may be used as plastic fats for confectionery, bakery and other edible uses.     

Trans-free bakery shortenings from mango kernel and mahua fats by fractionation and blending

Bakery shortenings prepared by hydrogenation contain high levels of trans fatty acids, which are considered to be risk factors for cardiovascular disease. The shortenings prepared from maogo kernel and mahua fats have no trans fatty acids. Mahua fat was fractionated by dry fractionation to obtain a high-melting fraction (10% yield, Mh1). Mango fat was fractionated by two-stage solvent fractionation, separating about 15% high-melting fraction (Mk1) in the first stage, followed by 40% stearin (Mk2) in the second stage. The formulation containing 80% Mh1 and 20% of mango middle stearin fraction (Mk2) showed melting characteristics and onset and enthalpy of crystallization similar to those of commercial hydrogenated shortenings designed for cakes and biscuits. The formulation suitable for puff pastry shortening was prepared by blending 50% mango 1st stearin (Mk1) and 50% mahua fat with addition of 5–7% of fully hydrogenated vegetable oil. The formulations having melting characteristics similar to those of commercial cake and biscuit shortenings were also prepared by blending 40% mango fat and 60% mahua fat with 5–7% incorporation of fully hydrogenated peanut oil. However, these formulations showed delayed transition to the stable forms compared to those of commercial samples. Fatty acid composition revealed that commercial hydrogenated shortenings consisted of 18–29% trans oleic acid, whereas the formulations we prepared did not contain any trans acids. The iodine values of commercial samples were 57–58, whereas the value for the formulations prepared were 47–53. The consistency of the prepared samples as measured by cone penetrometer was slightly harder than commercial samples. These studies showed that it is possible to prepare bakery shortenings with no trans fatty acids by using mango and mahua fats and their fractions.     

Detection of foreign fat in milk fat from different continents by triacylglycerol analysis

The adulteration of bovine milk fat with foreign fat can be detected by the analysis of its triacylglycerol (TAG) composition in combination with TAG formulae to calculate S‐values. With genuine milk fats these S‐values must not exceed certain limits already laid down in German and European analytical standards since 1994. The present validity of the TAG formulae and corresponding S‐ranges was confirmed by analysis of 148 recently produced European milk fat samples comprising a wide variation in lipid composition. Additionally, representative milk fat collections from New Zealand (n = 31) and South Africa (n = 10) were analyzed for their TAG composition to check the applicability of the TAG method to non‐European dairy products. These samples were identified as pure and unadulterated as well. All the analyzed samples (n = 189) provided S‐values clearly within the admissible limits. Consequently, the composition of genuine milk fat from different continents still fits the S‐ranges formerly established for Europe, and the TAG method most likely can be applied globally. Limitations have to be considered with technologically processed milk fat or fat from low‐fat milk products such as skim milk or buttermilk.     

Application of a Novel,Heated, Nine-Reflection ATR Crystal and a Portable FTIR Spectrometer to the Rapid Determination of Total <Emphasis Type="Italic">Trans</Emphasis> Fat

Since trans fat labeling requirements became mandatory in the US and many other countries, there has been a need for rapid and accurate analytical methodologies that can facilitate compliance with the various regulations. The determination of total trans fatty acids by mid-infrared (IR) spectroscopy is a widely used procedure that was standardized and validated as AOCS Official Method Cd 14e-09 (negative second derivative infrared spectroscopic method for the rapid (5 min) determination of total isolated trans fat) in 2009. The C–H out-of-plane deformation mid-IR band observed at 966 cm⁻¹ is uniquely characteristic of isolated (non-conjugated) double bonds with trans configuration. AOCS Official Method Cd 14e-09, the most recent attenuated total reflection-Fourier transform IR (ATR-FTIR) official method, entails the measurement of the height of the negative second derivative of the trans absorption band. In the present study, the performance of a novel, portable FTIR system equipped with a heated 9-bounce diamond ATR crystal was evaluated and compared to that of a conventional benchtop single-bounce ATR-FTIR spectrometer. The introduction of the 9-bounce diamond ATR crystal resulted in the lowering of the limit of quantification of trans fat, as a percentage of the total fat, from approximately 2 to 0.34%. The data collected from accurately weighed gravimetric standards and 28 unknown test samples ranging in trans fat content from about 0.5 to 54%, as a percentage of the total fat, indicated that this IR official method and the use of the new 9-bounce portable ATR-FTIR instrumentation could lead to a five-fold enhancement in sensitivity relative to single-bounce systems. Implementing these changes would facilitate regulatory compliance and verification of fat and oil samples for trans fat content in the US and other countries, since all of the published regulations (e.g., “0 g trans fat per serving”) have levels of trans fat, as percentage of total fat, that exceed 0.34%.     

芒果叶和扁桃叶的紫外光谱鉴别

为建立芒果叶及其易混品扁桃叶的紫外光谱鉴别方法。以中药鉴别紫外谱线组法进行实验。芒果叶和扁桃叶的紫外谱线组图像、吸收峰数目及峰位等存在一定差异,可以作为鉴别的依据。该方法可简单、准确的鉴别芒果叶和扁桃叶。     

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.     

Oil‐Fat Mixtures with Low Solid Fat Concentration: Influence of Fat Concentration and Cooling Conditions

Uniform suspension of particulates (salt or spices) in oil‐based marinades requires a gel behavior of the matrix. This can be achieved by adding a solid fat to the liquid oil. Besides rheology, appearance and thermal stability are important for the utilization as marinades. The influence of solid fat concentration (c_fat = 2.5–5.5 wt%) and average cooling speed (1.4, 2.6, and 4.7 °C/min) on the functional properties of oil‐fat gels from palm fat and canola oil was investigated. Oil‐fat mixtures showed complex physiochemical behavior depending on the solid fat concentration and cooling rate. All samples had a shear‐thinning behavior. Yield stresses and apparent viscosities increased at a constant cooling rate with increasing solid fat concentration. Frequency dependence of storage and loss modulus showed a transition from a viscous solution to a weak gel at c_fat > 3.5 wt%. Samples at increasing cooling rates transitioned to weak gels at lower fat concentration (2.5 wt%). Mixtures became turbid and increasingly whiter as both solid fat concentration and cooling rates increased, which was explained by increased light‐scattering by fat crystal aggregates. Results show the critical importance of proper formulation and preparation conditions on the functionality of oil‐based marinades.     

Lactation curves and effect of pup removal on milk fat of C57BI/6J mice fed different diet fats

Groups of C57BI/6J mice, fed either acis (C-Diet) ortrans diet (T-Diet) were milked without preconditioning at 6, 8, 10 and 12 dayspostpartum. On day 10, groups of mice were also milked 4, 6 and 18 h after separation of the pups. Except for the 18-h separation, all T-Diet fed animals produced milk of lower fat content than did the C-Diet animals (P<0.001) throughout the lactation period measured. In the C-Diet mice, the 6-h separation period resulted in a decrease (P<0.03) in fat, but the diet-depressed milk fat of T-Diet animals was not decreased further until the 18-h separation period. Milk volume increased as lactation progressed and was greatly increased as a result, of preconditioning (P<-0.001), even at 4 h of separation when fat was not reduced, and was always greater for T-Diet animals. Within diet groups, fatty acid composition was similar throughout the lactation period studied and was not affected by preconditioning, except in the 18-h separation period, whende novo fatty acids were significantly reduced (P≤0.05). The data are consistent with the hypothesis that preconditioning results in lowered milk fat values and that preconditioning techniques can explain discrepancies in literature values for murine milk fat. Based on a paper presented at the Symposium on Milk Lipids held at the AOCS Annual Meeting, Baltimore, MD, April, 1990.     

Iodine number determination of milk fat and vegetable fats by refractometry

A refractometric method for the estimation of iodine number of milk fat has been suggested. About 0.2 ml of milk fat was iodinated with ca. 10 ml Wijs iodine reagent for 3 min using mercuric acetate as catalyst. The iodinated fat showed a higher refractive index than the original fat. The changes in refractive indices showed a very high correlation with the iodine values of the fats (T=0.9993). The average of the ratios of change in refractive index to iodine number was 50.7×10⁻⁵, from which the iodine number of milk fat can be calculated. The method can also be applied to vegetable fats. The ratios of change in refractive index to iodine number for the oils of peanut, rapeseed, soybean, niger, sesame, and sunflower were similar, and the average was 45.2×10⁻⁵. The ratio for linseed oil was 38.4×10⁻⁵, and for coconut fat it was similar to that of milk fat.     

Modifying milk fat composition of dairy cows to enhance fatty acids beneficial to human health

There is increased consumer awareness that foods contain microcomponents that may have beneficial effects on health maintenance and disease prevention. In milk fat these functional food components include EPA, DHA, and CLA. The opportunity to enhance the content of these FA in milk has improved as a result of recent advances that have better defined the interrelationships between rumen fermentation, lipid metabolism, and milk fat synthesis. Dietary lipids undergo extensive hydrolysis and biohydrogenation in the rumen. Milk fat is predominantly TG, and de novo FA synthesis and the uptake of circulating FA contribute nearly equal amounts (molar basis) to the FA in milk fat. Transfer of dietary EPA and DHA to milk fat is very low (<4%); this is, to a large extent, related to their extensive biohydrogenation in the rumen, and also partly due to the fact that they are not transported in the plasma lipid fractions that serve as major mammary sources of FA uptake (TG and nonesterified FA). Milk contains over 20 isomers of CLA but the predominant one is cis-9,trans-11 (75–90% of total CLA). Biomedical studies with animal models have shown that this isomer has anticarcinogenic and anti-atherogenic activities. cis-9,trans-11-CLA is produced as an intermediate in the rumen biohydrogenation of linoleic acid but not of linolenic acid. However, it is only a transient intermediate, and the major source of milk fat CLA is from endogenous synthesis. Vaccenic acid, produced as a rumen biohydrogenation intermediate from both linoleic acid and linolenic acid, is the substrate, and Δ9-desaturase in the mammary gland and other tissues catalyzes the reaction. Diet can markedly affect milk fat CLA content, and there are also substantial differences among individual cows. Thus, strategies to enhance milk fat CLA involve increasing rumen outflow of vaccenic acid and increasing Δ9-desaturase activity, and through these, several-fold increases in the content of CLA in milk fat can be routinely achieved. Overall, concentrations of CLA, and to a lesser extent EPA and DHA, can be significantly enhanced through the use of diet formulation and nutritional management of dairy cows.     

Biomarkers for intake of dairy fat and dairy products

The aim of this study was to correlate the fatty acids characteristic of dairy fat (14:0, 14:1, 15:0, 17:0 and 17:1) in adipose tissue, serum lipid fractions and the estimated intake of dairy fat, and to investigate whether they can be used as biomarkers for dairy fat/product intake. The highest correlations were observed between 14:0 in adipose tissue and the estimated intakes of 14:0 (r = 0.60) and dairy fat (r = 0.50), and between 15:0 in adipose tissue and the estimated intakes of 15:0 (r = 0.55) and dairy fat (r = 0.55). Among the fatty acids in serum lipid fractions, 15:0 in cholesteryl esters (CE) and triacylglycerols showed the highest correlation to both 15:0 in adipose tissue, intakes of 15:0, dairy fat and dairy products. The results from our study suggest that the contents of fatty acids characteristic of dairy fat (14:0, 14:1, 15:0, 17:0, 17:1) in adipose tissue might be used as markers not only for the intake of dairy fat, but also of dairy products (times/day). When adipose tissue specimens are not available, 15:0 in serum CE appears to be the best marker for dairy fat intake. It was also observed that fatty acids from dairy fat are incorporated differently into serum lipid fractions and adipose tissue.     

Nutrition Labeling: Rapid Determination of Total <Emphasis Type="Italic">trans</Emphasis> Fats by Using Internal Reflection Infrared Spectroscopy and a Second Derivative Procedure

In 2006, the US FDA mandated the declaration of the total trans fat content on the Nutrition Fact label of foods including dietary supplements when a product contained 0.5 or more grams of trans fatty acid per serving; the minimum corresponding trans fat content is estimated to be approximately 2% of total fat. The FDA definition is based on chemical structure and includes only fatty acids with one or more isolated double bonds in the trans configuration. Several issues negatively impacted the sensitivity of the current official infrared (IR) methods, thus limited the quantitation of trans fat to 5% of total fat. To improve sensitivity and accuracy and to meet the labeling requirement, a new internal reflection IR procedure called negative second derivative is described and evaluated for the quantitation of total trans fat in the present study. The enhanced spectral features of a second derivative resolved issues that traditionally limited the sensitivity of the IR methodology. Calibration standard mixtures starting at approximately 0.5% trielaidin in the total fat (tripalmitin or triarachidin) were successfully generated and used to determine the trans fat levels for unknown test samples with trans content as low as approximately 1% of total fat. Quantitative IR data were compared to those obtained by gas chromatography and were found to be in good agreement.     

Enzyme-assisted extraction of chicken skin protein hydrolysates and fat: Degree of hydrolysis affects the physicochemical and functional properties

Enzyme-assisted extraction (EAE) of oils/fats involves the disruption of the cell wall of source material using enzymes to facilitate the release of oil. When proteases are used as the enzyme, EAE ends in the extracted oil as well as the protein hydrolysates. Herein, the EAE (using a commercial protease, Alcalase) was exploited to obtain fat and protein hydrolysates from chicken skin. Degree of hydrolysis (DH, the percentage ratio of cleaved peptide bonds), which showed a logarithmic correlation with the reaction time, was found to affect the properties of the products. As the DH increased, the peptide chain length of protein hydrolysates decreased which was confirmed by SDS-PAGE analysis. With the increase of DH, the emulsifying activity index, foaming capacity, and oil holding capacity of the hydrolysates decreased but the solubility and emulsion stability index increased (p < 0.05). The DPPH free radical scavenging activity of the hydrolysates increased with the DH up to DH = 39.62% but decreased thereafter (p < 0.05). EAE resulted in a rise in fat yield and the fat contained a higher amount of unsaponifiables and lower free fatty acids (FFA) content, as compared to the control treatment (No enzyme, 80°C, 2 h, p < 0.05). DH affected the fat yield and the unsaponifiables content of the fat, positively (p < 0.05). However, it did not affect the fat FFA content and iodine value (p > 0.05). Results obtained here showed DH can be used as an effective measure for controlling the physicochemical and functional properties of chicken skin protein hydrolysates and fat in the EAE process.     

Fasting and postprandial lipid response to the consumption of modified milk fats by guinea pigs

The objective of the present study was to investigate the effect of three modified milk fats with different melting profiles on fasting and postprandial lipid responses and on fecal fat content in guinea pigs. We hypothesized that the consumption of modified milk fat with a high m.p. results in reduced fasting and postprandial lipid responses compared with that of modified milk fat fractions with lower m.p. To test this hypothesis, male Hartley guinea pigs were fed isoenergetic diets containing 110 g of fat/kg, either from one of the three modified milk fats with high (HMF), medium (MMF), or low melting profiles (LMF), or from one of the two reference fats as whole mil fat (MF) or a fat blend similar to that of nonhydrogenated soft margarine (MA) for 28 d. Food intake (P<0.05) and body weight gain (P<0.05) were reduced in the animals fed the HMF diet compared with the other groups. In the fasting state, plasma LDL cholesterol was highest in animals fed the LMF diet, intermediary in those fed the MMF and MF diets, and lowest in those fed the HMF and MA diets (P<0.05). Postprandially, the areas under the 0- to 3-h curves for the changes in plasma TG were lower in the HMF group than in the MA- and LMF-fed guinea pigs (P<0.05). The fecal fat content was higher (P<0.05) in the HMF group compared to the other milk fat groups. The present results suggest that modified milk fats can impact food intake, body weight gain, fasting cholesterolemia, and postprandial triglyceridemia, and these changes may be attributed to an altered fat absorption.     

Strategien zur Fettsubstitution in Lebensmitteln

Strategies for the substitution of dietary fat. The increasing incidence of overweight and obesity in Europe and North America has to be reduced by lowering the energy and fat consumption. The supply of low-fat products is helpful to decrease the individual fat intake. A simple reduction of dietary fat content, however, is often combined with a loss of sensoric and technological food quality. Therefore, it is necessary to substitute dietary fat either by fat analogs or by fat replacers (also called fat mimics of fat mimetics). Fat analogs having no or a very low energetic value, e.g. special triglycerides, carbohydrate polyesters, retrofats, long-chain ethers, are fat-like in their functional properties (appearance, hydrophobicity, temperature behaviour). Fat replacers having lower energy values than dietary fat are represented by microparticulated proteins and carbohydrates, e.g. inulin, starch, dextrins, water-binding and jelling substances. They predominantly simulate the sensoric, but not the whole range of other functional properties of dietary fat. Due to their toxicological safety and sensoric quality, however, their importance as substitutes for dietary fat will increase.     

Validation of a gas‐chromatographic method for the determination of milk fat contents in mixed fats by butyric acid analysis

Gas‐chromatographic analysis of butyric acid (C4) in mixed spreadable fats can be used to calculate the milk fat proportion, either by additional analysis of the underlying pure milk fat (component sample) or by using a mean C4 content instead. After comparison of several analytical variants and subsequent development of an improved draft standard for quantitation of milk fat in mixed fats, this draft was checked for accuracy in three EU‐wide ring tests performed with 26 participating laboratories. Due to the natural variation of the butyric acid content in European milk fats, deviations from the actual milk fat content may amount up to ± 10% in addition to analytical errors when calculating with a mean C4 content instead of the C4 content of a component sample. Though the reproducibility could be improved by application of correction factors derived from a reference fat, only the calculation based on the additional analysis of a component sample of the pure milk fat led to an acceptable accuracy concerning the trueness of the results in combination with good repeatability (r) and reproducibility (R). Finally, several further improvements of the draft standard led to a precision of r = 4.3% and R = 6.0% relative to the mean of two milk fat contents determined. Thus, the tested procedure proved its suitability for a control method of the declared milk fat content in mixed fat spreads.     

Influence of hydrogenation and antioxidants on the stability of soybean oil biodiesels

This study examined the influence of hydrogenation and antioxidant activity of natural products derived from Mangifera indica on soybean biodiesel stability. Biodiesels were prepared with refined, semi‐refined, and partially hydrogenated soybean oil and the stability was evaluated in a Rancimat apparatus. The biodiesel from partially hydrogenated soybean oil showed greater stability (11.9 h), exceeding the standard limit established by the Brazilian National Petroleum Agency (6 h). Gallic acid, tannic acid, and mango seed kernel extract were evaluated as antioxidants. The gallic acid showed higher antioxidant ability than the other products, increasing twofold the oxidative stability (20.8 h). The results indicate the importance of mango seed as a source of efficient antioxidants for biodiesel just like gallic acid. Practical applications: The results provide detailed information about: (i) the influence of hydrogenation on soybean biodiesel stability; (ii) the antioxidant activity of natural products derived from M. indica; (iii) and the importance of each phenolic constituent on the stability. Mango seed is an abundant waste product from fruit juice industry in Brazil and could be used for obtaining an effective antioxidant additive for biodiesel.     

Acidolysis Reaction of Sal Fat (Shorea robusta) with Palmitic Acid

Acidolysis reaction of sal fat (Shorea robusta) with palmitic acid has been studied in relation to the operating variables like catalyst system and concentration, reaction temperature and time and molar ratios of reactants with the object of introducing more palmitic acid which is low in sal fat. The results demonstrate that as low as 2.5% and as high as 39% palmitic acid can be introduced in sal fat at the expense of other acids under the influence of various operating conditions. The products obtained differ from original sal fat in respect of chemical composition and slip point. The importance of such study is that there are possibilities of getting plastic fats of diverse properties for edible and industrial uses.     

Dietary Fat Does Not Overcome trans-10, cis-12 Conjugated Linoleic Acid Inhibition of Milk Fat Synthesis in Lactating mice

Trans-10, cis-12 conjugated linoleic acid (CLA) is a potent inhibitor of milk fat synthesis in the cow and similarly reduces milk fat in rodents. The objective of this study was to determine whether dietary fat can overcome CLA inhibition of milk fat concentration in lactating mice. Wild type C57Bl/6J mice (n = 31) were fed semipurified diets containing either low fat (LF; 4% fat) or high fat (HF; 23.6% fat) starting 4–6 days postpartum. Dietary fat was increased by inclusion of high oleic sunflower oil. After 2 days on the experimental diets, lactating dams were orally dosed with either water (control) or trans-10, cis-12 CLA (20 mg/day) for 5 days. CLA treatment decreased pup growth similarly in both HF and LF diets. Milk fat percent was increased over 16% by the HF diet and decreased over 12% by CLA, but there was no interaction of dietary fat and CLA. Both CLA and the HF diet reduced the proportion of short- and medium-chain fatty acids that originate from de novo synthesis, and there was no interaction of diet and CLA. CLA had no effect on the percent of preformed fatty acids, but the HF diet increased their abundance. Dietary fat and CLA both modified mammary expression of lipogenic enzymes and regulators, but no interactions were observed. In conclusion, CLA reduced milk fat concentration and litter growth, but these effects were not overcome by increased dietary fat from high oleic sunflower oil. CLA inhibition of milk fat in the mammary gland is not substrate dependent, and the mechanism is independent from dietary supply of oleic acid.