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Solid Fat Content (solid + fat_content)
Selected AbstractsProduction of trans -free margarine stock by enzymatic interesterification of rice bran oil, palm stearin and coconut oilJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 4 2010Prakash Adhikari Abstract BACKGROUND:Trans -free interesterified fat was produced for possible usage as a spreadable margarine stock. Rice bran oil, palm stearin and coconut oil were used as substrates for lipase-catalyzed reaction. RESULTS: After interesterification, 137,150 g kg,1 medium-chain fatty acid was incorporated into the triacylglycerol (TAG) of the interesterified fats. Solid fat contents at 25 °C were 15.5,34.2%, and slip melting point ranged from 27.5 to 34.3 °C. POP and PPP (,-tending TAG) in palm stearin decreased after interesterification. X-ray diffraction analysis demonstrated that the interesterified fats contained mostly ,, polymorphic forms, which is a desirable property for margarines. CONCLUSIONS: The interesterified fats showed desirable physical properties and suitable crystal form (,, polymorph) for possible use as a spreadable margarine stock. Therefore, our result suggested that the interesterified fat without trans fatty acid could be used as an alternative to partially hydrogenated fat. Copyright © 2010 Society of Chemical Industry [source] Moisture barrier and physical properties of acetylated derivatives with increasing acetylation degreeEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 5 2009Claire Bourlieu Abstract Four acetostearin products with increasing acetylation degree were synthesized by chemical interesterification followed by fractionation/blending stages. Their physical properties and functional barrier properties were studied and compared to the properties of technical tristearin. Increasing acetylation degree (AD) modified the triacylglycerols crystal habits and probably led to an increase in acyl chain fluidity, which induced, at macroscopic levels, a decrease in solid fat content (SFC), in melting point, in surface and bulk material hydrophobicity, and an increased moisture effective diffusivity. Water vapor permeability (WVP) coefficients of the materials were partially influenced by the AD factor, but also by the development of macroscopic cracks in lipids presenting high SFC. Acetylated stearin up to 47% (acetyl mol/mol of esterified chain) presented the lowest WVP at 20,°C resulting from an adequate balance between hydrophobicity and mechanical properties of the material. [source] Effects of hydrogenation parameters on trans isomer formation, selectivity and melting properties of fatEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 3 2008Anar Musavi Abstract Effects of hydrogenation conditions (temperature, hydrogen pressure, stirring rate) on trans fatty acid formation, selectivity and melting behavior of fat were investigated. To this aim, soybean oil was hydrogenated under various conditions and fatty acid composition, trans isomer formation, slip melting point (SMP), solid fat content (SFC) and iodine number (IV) of the samples withdrawn at certain intervals of the reactions were monitored. A constant ratio (0.03%) of Nysosel 222 was used in the various combinations of temperature (150, 165 and 180,°C), stirring speed (500, 750 and 1000,rpm) and hydrogen pressure (1, 2 and 3,bar). Raising the temperature increased the formation of fatty acid isomers, whereas higher stirring rates decreased this formation, while changes in hydrogen pressure had no effect or slightly reduced it, depending on other parameters. Results also indicated that the trans fatty acid ratio increased with IV reduction, reached the highest value when the IV was about 70 and decreased at IV < 70 due to saturation. Selectivity values (S21) at that point ranged between 5.78 and 11.59. Lower temperatures and higher stirring rates decreased not only the trans isomer content but also the S21 values at significant levels. However, same effects were not observed with the changes in hydrogen pressure. It was determined that a high SMP does not necessarily mean a high SFC. Selective conditions produced samples with higher SFC but lower SMP, which is possibly because of higher trans isomer formation as well as lower saturation. [source] Influence of filling fat type on praline products with nougat fillingEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 12 2007Biljana Pajin Abstract The aim of this research was to examine the composition and functional characteristics of three samples of commercial filling fat intended for the making of nougat fillings for confectionary products. The crystallization rate of the fats was measured under static conditions using the NMR technique and under dynamic conditions as well as using a rotational rheometer. The functional characteristics of the fats were estimated by means of sensory values of the prepared praline product. Under the static conditions, all investigated filling fats showed a fast crystallization rate (,2,4%/min). The sample with the highest lauric acid contents started to crystallize immediately (no induction period). The longest induction period was found for the sample with the lowest saturated fatty acid and trans fatty acid contents. During the crystallization under dynamic conditions, all investigated samples started to crystallize more rapidly (rapid viscosity increase) at practically the same temperature (,17,°C). Measuring solid fat content and viscosity are two approaches of determining the suitability of a filling fat to be used in pralines. Both measurements provide valuable information, and particularly viscosity build-up is very important from the view of production on factory scale. [source] Production of zero trans Iranian vanaspati using chemical transesterification and blending techniques from palm olein, rapeseed and sunflower oilsINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 3 2008Jamshid Farmani Summary Chemical transesterification and blending techniques were used for producing zero trans fats suitable for use as Iranian vanaspati. Triple blends of palm olein (POo), rapeseed (RSO) and sunflower oil (SFO) were subjected to two different treatments: (i) blending and then transesterification (BT) and (ii) transesterification of pure POo before blending with RSO and SFO (TB). The changes in slip melting point (SMP), solid fat content (SFC), carbon number (CN) triacylglycerol (TAG) composition, induction period (IP) of oxidation at 120 °C and IP of crystallisation at 20 °C of blends before and after treatments were investigated. Both BT and TB methods resulted in an increase in the CN48 TAG molecules, SMP and SFC, and a decrease in the IP of oxidation and crystallisation of initial blends. Samples made by TB method had higher CN48 TAG content, SMP, SFC and IP of oxidation, and lower IP of crystallisation than those made by BT method. Correlation between SFC at 20 °C and saturated fatty acid (SFA) content of the treated blends indicated that the SFA must be higher than 33.1% and 26.8% for BT and TB methods, respectively, to obtain fats suitable for use as vanaspati. [source] Food applications of trans fatty acid substitutesINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 5 2007Paul Wassell Summary The review outlines the increasing need to reduce trans fatty acids, and addresses the functionality issues of various trans free solutions through discussion of hydrogenation, interesterification, and fractionation, and their influence on fat crystallisation and solid fat content. Caution is urged not to focus solely on physio-chemical aspects, but to approach trans free designing for specific food applications from a multidisciplinary angle. Examples of specific applications; margarines, shortenings and frying oils are given. The review also offers a glimpse into what the future trans free trends may hold. [source] Properties of High-Oleic Palm Oils Derived by Fractional CrystallizationJOURNAL OF FOOD SCIENCE, Issue 3 2008M.R. Ramli ABSTRACT:, High-oleic palm oil (HOPO) with an oleic acid content of 59.0% and an iodine value (IV) of 78.2 was crystallized in a 200-kg De Smet crystallizer with a predetermined cooling program and appropriate agitation. The slurry was then fractionated by means of dry fractionation at 4, 8, 10, 12, and 15 °C. The oil and the fractionated products were subjected to physical and chemical analyses, including fatty acid composition, triacylglycerol and diacylglycerol composition, solid fat content, cloud point, slip melting point, and cold stability test. Fractionation at 15 °C resulted in the highest olein yield but with minimal oleic acid content. Due to the enhanced unsaturation of the oil, fractionation at relatively lower crystallization temperature showed a considerable effect on fatty acid composition as well as triacylglycerol and diacylglycerol composition of liquid fractions compared to higher crystallization temperature. The olein and stearin fractionated at 4 °C had the best cold stability at 0 °C and sharper melting profile, respectively. [source] Analytical Techniques for Nucleation Studies in Lipids: Advantages and DisadvantagesJOURNAL OF FOOD SCIENCE, Issue 9 2004M. Cerdeira ABSTRACT: Crystallization is generally considered a 2-step process. The 1st step, nucleation, involves the formation of molecular aggregates with a critical size great enough to become stable. During the 2nd step, nuclei grow and develop into crystals. Distinguishing between nucleation and growth constitutes a major challenge in lipid crystallization studies. Thus, it is of great importance to discuss the information obtained from the different techniques that are usually used to study nucleation behavior such as nuclear magnetic resonance (NMR), differential scanning calorimetry (DSC), rheological techniques, light-scattering techniques such as turbidimetry and scanning diffusive light scattering (SDLS), polarized light microscopy (PLM), and laser polarized optical sets such as laser polarizedlight turbidimetry (LPLT). Techniques to describe the nucleation process must be very sensitive to disregard growth. When crystallization is followed by methods such as DSC, NMR, and rheological measurements, at times, small amounts of crystals are present in the melt before any solids are detected. Clearly, at this stage, well beyond the induction time for nucleation (,), these methods are measuring crystal growth. Techniques of low sensitivity for solid fat contents lower than 0.1% must not be used to evaluate nucleation effects. Sensitive turbidimeters with detectors that saturate below 0.3% solid fat content give good results as do scanning diffusive light-scattering equipment. Although the PLM technique is sensitive enough for these kinds of studies, an understanding of important basic concepts is essential. Laser optical sets are the most appropriated methods to study nucleation in fats systems. [source] Physicochemical, textural and viscoelastic properties of palm diacylglycerol bakery shortening during storageJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 13 2010Ling-Zhi Cheong Abstract BACKGROUND: Diacylglycerol (DAG), which has health-enhancing properties, is sometimes added to bakery shortening to produce baked products with enhanced physical functionality. Nevertheless, the quantity present is often too little to exert any positive healthful effects. This research aimed to produce bakery shortenings containing significant amounts of palm diacyglycerol (PDG). Physicochemical, textural and viscoelastic properties of the PDG bakery shortenings during 3 months storage were evaluated and compared with those of commercial bakery shortening (CS). RESULTS: PDG bakery shortenings (DS55, DS64 and DS73) had less significant increments in slip melting point (SMP), solid fat content (SFC) and hardness during storage as compared to CS. Unlike CS, melting behaviour and viscoelastic properties of PDG bakery shortenings remained unchanged during storage. As for polymorphic transformation, CS contained only , crystals after 8 weeks of storage. PDG bakery shortenings managed to retard polymorphic transformation for up to 10 weeks of storage in DS55 and 12 weeks of storage in DS64 and DS73. CONCLUSION: PDG bakery shortenings had similar if not better storage stability as compared to CS. This is mainly due to the ability of DAG to retard polymorphic transformation from ,, to , crystals. Thus, incorporation of DAG improved physical functionality of bakery shortening. Copyright © 2010 Society of Chemical Industry [source] Fatty acid and triacylglycerol composition and thermal behaviour of fats from seeds of Brazilian Amazonian Theobroma speciesJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 13 2002M Victoria Gilabert-Escrivá Abstract Raw materials for cocoa butter substitutes, replacements or equivalents depend mostly on the unsteady supply from wild stands of plants, while there is no current supply of Neotropical origin. Seed fats from Theobroma species (T cacao, T bicolor, T grandiflorum, T obovatum, T subincanum, T speciosum, T sylvestre and T microcarpum, plus the closely related species Herrania mariae) were analysed for fatty acid and triacylglycerol composition by gas and liquid chromatography respectively, for iodine value, for melting point by open capillary tube and for solid fat content (SFC) by nuclear magnetic resonance. All Theobroma species had significantly lower palmitate levels than T cacao, except for T sylvestre and T speciosum, T microcarpum presented highly unsaturated fat (C18:2), while H mariae had high levels of arachidate. Fats from T sylvestre and T speciosum had a similar iodine value to T cacao and a higher melting point. No fat from the other species presented a similar melting profile to cocoa butter. T sylvestre and T bicolor were the most similar to T cacao but had a higher SFC at human body temperature. T sylvestre and T speciosum seed fats had more POP than cocoa butter. Fats from seeds of T speciosum, T sylvestre and T bicolor could be recommended as cocoa butter substitutes, while fats from species of the section Glossopetalum could be employed in products requiring fats with a lower melting point. © 2002 Society of Chemical Industry [source] Effect of feeding oilseed supplements to dairy cows on ruminal and milk fatty acid compositionJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 7 2002Brian F McNamee Abstract The objective of this study was to compare the effects of oilseed-based supplements, rapeseed and linseed, against a barley-based control, on the fatty acid composition, and subsequent solid fat ratio, of the milk fat from dairy cows. In addition, as a means of understanding the digestive processes which influence the milk fat composition, ruminal extracts were collected from the cows and analysed for fatty acid composition. Four lactating dairy cows each fitted with a rumen fistula were provided with silage and one of four concentrate diets. The main constituent of the concentrate supplements was either rapeseed (ground or unground), linseed (unground) or a barley control. The diets were offered in accordance with a 4,×,4 Latin square arrangement. The oilseed-supplemented concentrates provided the cows with 620,640,g fatty acids day,1. Experimental treatments were provided to the cows for 2 weeks, after which ruminal extracts were collected over a 24,h period and a milk sample was taken. All extracts were analysed for fatty acid composition. The diets fed influenced the long-chain fatty acid composition of the ruminal extracts and milk fat. The proportion of C18:1n-9 in the ruminal extracts increased from 202,224 to 282,321,g,kg,1 of the total fatty acids when the cows were provided with the rapeseed-based diets. The linseed-based diet increased the C18:1n-9 proportion of the ruminal extracts from 164 to 218,g,kg,1 of the total fatty acids. Both rapeseed-based diets also resulted in a higher proportion of C18:0 in the ruminal extract, possibly owing to biohydrogenation of the dietary fatty acids. This proportion of C18:0 in the ruminal extract was lowest immediately after feeding, increasing to a maximum 4,6,h later. Both rapeseed-based concentrates increased the proportion of C18:1n-9 in the milk fat to approximately 300,g,kg,1 of the total fatty acids as compared with 214,g,kg,1 for the control. The proportion of C18:1n-9 in the milk fat from the cows offered the linseed-based concentrate was 246,g,kg,1 of the total fatty acids. There were also significant decreases in the proportions of C16:0 in the milk fat from the cows offered all oilseed-based concentrates. There was no difference between the fatty acid compositions of the milk fats from the cows fed the ground or unground rapeseed-based supplements. The oilseed-based supplements also resulted in significant decreases in the solid fat content of the milk fat at temperatures ranging from 0 to 35,°C, which would be indicative of a softer, more spreadable butter. © 2002 Society of Chemical Industry [source] Influence of silica gel in production of diacylglycerol via enzymatic glycerolysis of palm oleinEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 6 2009Chiou Moi Yeoh Abstract Enzymatic glycerolysis was explored in this paper for the production of diacylglycerol (DAG) oils from palm olein. Three commercial enzymes, Lipozyme TL,IM, Lipozyme RM,IM and Novozym 435 were used for their ability to synthesize DAG in a solvent-free system. Novozym 435 was found to be the more effective enzyme, resulting in a high DAG production even in the absence of an adsorbent such as silica gel. The yields of DAG were between 43 and 50,wt-%. Lipozyme TL,IM and RM,IM, being supported on hydrophilic materials, require an adsorbent to allow slow release of glycerol for reaction with the enzyme and oil. In the absence of silica, no reaction was observed. The success of the reaction is therefore very dependent on the amount of silica used. The yields of DAG using Lipozyme TL,IM and RM,IM were 52 and 45,wt-%, respectively. In addition, the degree of reduction in tocopherols and tocotrienols appeared correlated with the efficacy of the glycerolysis reaction. Changes in the slip melting points and solid fat contents of the products are indicative of the reaction occurring. [source] Analytical Techniques for Nucleation Studies in Lipids: Advantages and DisadvantagesJOURNAL OF FOOD SCIENCE, Issue 9 2004M. Cerdeira ABSTRACT: Crystallization is generally considered a 2-step process. The 1st step, nucleation, involves the formation of molecular aggregates with a critical size great enough to become stable. During the 2nd step, nuclei grow and develop into crystals. Distinguishing between nucleation and growth constitutes a major challenge in lipid crystallization studies. Thus, it is of great importance to discuss the information obtained from the different techniques that are usually used to study nucleation behavior such as nuclear magnetic resonance (NMR), differential scanning calorimetry (DSC), rheological techniques, light-scattering techniques such as turbidimetry and scanning diffusive light scattering (SDLS), polarized light microscopy (PLM), and laser polarized optical sets such as laser polarizedlight turbidimetry (LPLT). Techniques to describe the nucleation process must be very sensitive to disregard growth. When crystallization is followed by methods such as DSC, NMR, and rheological measurements, at times, small amounts of crystals are present in the melt before any solids are detected. Clearly, at this stage, well beyond the induction time for nucleation (,), these methods are measuring crystal growth. Techniques of low sensitivity for solid fat contents lower than 0.1% must not be used to evaluate nucleation effects. Sensitive turbidimeters with detectors that saturate below 0.3% solid fat content give good results as do scanning diffusive light-scattering equipment. Although the PLM technique is sensitive enough for these kinds of studies, an understanding of important basic concepts is essential. Laser optical sets are the most appropriated methods to study nucleation in fats systems. [source] | ||||||||||