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1.
Oleogels have been studied in the past decade due to their potential to replace saturated fat in foods. Oleogelators have been mostly studied alone or in binary systems. Sometimes a single oleogelator cannot achieve all the technological properties necessary for a specific food application. Thus, the aim of this work was to investigate the interaction between candelilla wax (CLX), monoacylglycerols (MAG), and a fully hydrogenated oil (hardfat [HF]) in soybean and high‐oleic sunflower oils and to evaluate their physical properties. The concentration of the total oleogelator was between 5% and 10%, from pure CLX (5%), sample OP, up to many combinations of MAG, HF, and CLX samples O1, O2, O3, O4, O5, and O6. Samples were evaluated according to their microstructure, melting properties, rheological behavior, hardness, oil‐binding capacity (OBC), and thermal stability. Results showed that the addition of MAG and HF to CLX created a softer gel but improved its rheological properties. Changes in the physical properties were related to the various proportions of CLX, MAG, and HF rather than the overall concentration of structuring agents. For example, for a total concentration of 5% of the structuring agent, a decrease in the CLX concentration from 5% to 3% and the addition of HF and MAG resulted in a softer crystalline network. Increasing the overall concentration of oleogelators by increasing the amount of HF and/or MAG and maintaining the concentration of the CLX constant did not improve the hardness of the gel. This study showed that at least 3% of CLX must be added to the system to obtain a semisolid material independently of the amount of MAG and/or HF added.  相似文献   

2.
The aim of this work was to evaluate the characteristics of fillings used in cookies commercialized in Brazil and in USA according to their chemical composition, labels, nutritional information, ingredients list, and price. Fillings had approximately 25–32% of fat. In general, the composition of these fats consisted of approximately 50% of saturated fatty acids (SFA), mainly palmitic acid, and 50% of unsaturated fatty acids, mainly oleic acid. Brazilian samples had trans-fatty acids (TFA) in the range of 1–15% although in many cases their presence was not reported in the labels. USA product labels did not present a fixed portion weight but they showed detailed information about the types of fats used such as source and the process used for their production. In 70% of Brazilian product labels, the information shown in the ingredient list was limited to “vegetable fat,” which does not give enough information to consumers about the type of fat used. In addition, our results showed that low-trans-products or zero-trans-products, in which TFA were replaced by SFA, presented the highest prices. This research suggests that further legislation should be developed in Brazil to decrease the amount of TFA in foods and improve their nutritional properties.  相似文献   

3.
Three surveys of the content of trans fatty acids (TFA) in foods on the Danish market were carried out before and after the Danish regulation was introduced in January 2004 restricting the use of industrially produced (IP)‐TFA to a maximum of 2 g per 100 g fat in any food product. For this purpose, food samples were collected in 2002–3, 2004–5, and 2006–7. Of these, 60 paired samples (defined as samples included in two of the three investigations and with higher levels of IP‐TFA in the first determination than in the second) were identified. Comparisons of the fatty acid profiles showed that, in 68% of the products (e.g. sweets, cakes and cookies as well as fast food such as pie and tortilla), IP‐TFA were mainly substituted with saturated fatty acids (SFA). In some cases, the SFA source was coconut fat, whereas in other products, palm oil was added instead of partially hydrogenated oils. However, in important cases like frying fats, healthier fat substitutes with monounsaturated fatty acids were used. The surveys showed that the IP‐TFA content has been reduced or removed from most products with originally high IP‐TFA content, like French fries, microwave oven popcorn and various bakery products, so that IP‐TFA are now insignificant for the intake of TFA in Denmark.  相似文献   

4.
This study aimed to evaluate how lipid profiles affect the physicochemical properties, fatty acid profiles, and nutritional qualities of Brazilian margarines. We analyzed the texture profiles of 13 margarine samples and characterized their fatty acid composition, solid fat content, crystallization kinetics by NMR and thermal behavior by differential scanning calorimetry. The samples had total fat content ranging from 20% to 82% and low trans fatty acid (TFA) levels, except for two samples (5–7% elaidic acid). The fatty acid compositions of all samples showed a predominance of linoleic (23%–46%), oleic (20%–46%), and palmitic acids (7%–14%), indicating that they were formulated with soybean and palm oils. Saturated fat content ranged from 23% to 31%. Compared to the other evaluated samples, those with higher content of lipid and saturated fatty acids (SFAs) exhibited increased hardness and stickiness but reduced spreadability and adhesiveness. The presence of TFAs resulted in increased plasticity of the samples. Reformulation resulted in products with greater SFA levels, which had a negative impact as it increased the atherogenic index (AI: 0.22–0.48). The HF55 sample contained canola oil-based fat and presented the best nutritional and physical properties. This study is the first to report a complete evaluation of representative margarines, with essential information in reformulating to achieve lower SFA.  相似文献   

5.
The study was carried out to investigate the changes in saturated (SFA), monoene (MUFA), trans (TFA), and polyunsaturated (PUFA) fatty acids and the key fatty acid ratios (SFA/UFA, cis PUFA/SFA, C18:2/C16:0 and C18:3/C16:0) during potato chips frying in canola oil using single bounce attenuated total reflectance FTIR (SB‐ATR‐FTIR) spectroscopy. The data obtained from GC‐FID were used as reference. The calibration of main fat groups and their key fatty acid ratios were developed by partial least square (PLS) regression coefficients using 4000 to 650 cm?1 spectral range. FTIR PLS regression for the predicted SFA, MUFA, TFA, and PUFA were found 0.999, 0.998, 0.998, and 0.999, respectively, whereas for SFA/UFA, cis PUFA/SFA, C18:2/C16:0 and C18:3/C16:0 the regression coefficients were 0.991, 0.997, 0.996, and 0.994, respectively. We conclude that FTIR‐PLS could be used for rapid and accurate assessment of changes in the main fat groups and their key fatty acid ratios ratio during the frying process. Practical applications: FTIR‐ATR method is very simple, rapid, and environmentally friendly. No sample preparation is required and one drop of oil is enough for FTIR analysis. The proposed method could be applied for quick determination of key fatty acid ratios in the food processing industry.  相似文献   

6.
The aim of the present study was to compare the fatty acid composition, PUFA:SFA ratio, n6/n3 ratio, and TFA of different farm animal meats and offal products. These products were collected at a regional farm in Istanbul which is the most populous city in Turkey. The results of fatty acid composition analysis indicated that the major fatty acids of C16:0 (18.00–29.35 %), C18:0 (4.10–29.71 %), C18:1 (29.21–57.30 %), and C18:2 (1.37–18.60 %) were found in the samples. The total saturated fatty acids, total monounsaturated fatty acids and total polyunsaturated fatty acids content of the samples ranged between 30.00 and 61.83 %, 32.24 and 57.80 %, and 1.64 and 23.60 %, respectively (p < 0.05). Except for turkey abdominal fat, TFA content in all other samples showed a variation between 0.10 and 3.36 %. The PUFA:SFA ratio was higher in turkey meat (0.64) and was lower in sheep kidney fat (0.02). Moreover, the n6/n3 PUFA ratio changed between 2.90 and 22.28 (p < 0.05).  相似文献   

7.
Keeping in view the present day demand for foods with healthy fats, the effect of different fats namely hydrogenated fat (HF) and bakery fat (BF); oils—sunflower oil (SFO), soyabean oil (SBO), olive oil (OLO), palm oil (POO) and coconut oil (CNO) separately at the level of 7.5 % on the rheological, fatty acid profile and quality characteristics of parotta was studied. Addition of fats and oils decreased Farinograph water absorption, Amylograph peak viscosity, Alveograph resistance of dough to deformation and increased average abscissa at rupture. In the micrographs of parotta dough with fats, the protein matrix appeared thick and intact, whereas in the case of parotta dough with oils the protein matrix appeared slightly less intact. The spread ratio and overall quality of parotta with oils were higher than fats. The highest overall quality score was observed for parotta with OLO, followed in decreasing order by SFO, SBO, CNO, POO, HF and BF. Determination of fatty acid profile showed that the parottas with fats contained a high amount of trans fatty acids (TFA), while parottas with oils had no TFA. During storage up to 48 h, the parottas with oils remained softer than the parottas with fats.  相似文献   

8.
The fatty acid composition of 27 samples of commercial hydrogenated vegetable oils and 23 samples of refined oils such as sunflower oil, rice bran oil, soybean oil and RBD palmolein marketed in India were analyzed. Total cis, trans unsaturated fatty acids (TFA) and saturated fatty acids (SFA) were determined. Out of the 27 hydrogenated fats, 11 % had TFA about 1 % where as 11 % had more than 5 % TFA with an average value of about 13.1 %. The 18:1 trans isomers, elaidic acid was the major trans contributor found to have an average value of about 10.8 % among the fats. The unsaturated fatty acids like cis-oleic acid, linoleic acid and α-linolenic acid were in the range of 21.8–40.2, 1.9–12.2, 0.0–0.7 % respectively. Out of the samples, eight fats had fatty acid profiles of low TFA (less than 10 %) and high polyunsaturated fatty acids (PUFA) such as linoleic and α-linolenic acid. They had a maximum TFA content of 7.3 % and PUFA of 11.7 %. Among the samples of refined oils, rice bran oil (5.8 %) and sunflower oil (4.4 %) had the maximum TFA content. RBD palmolein and rice bran oils had maximum saturated fatty acids content of 45.1 and 24.4 % respectively. RBD palmolein had a high monounsaturated fatty acids (MUFA) content of about 43.4 %, sunflower oil had a high linoleic acid content of about 56.1 % and soybean oil had a high α-linolenic acid content of about 5.3 %.  相似文献   

9.
Individual FA have diverse biological effects, some of which affect the risk of cardiovascular disease (CVD). In the context of food-based dietary guidance designed to reduce CVD risk, fat and FA recommendations focus on reducing saturated FA (SFA) and trans FA (TFA), and ensuring an adequate intake of unsaturated FA. Because stearic acid shares many physical properties with the other long-chain SFA but has different physiological effects, it is being evaluated as a substitute for TFA in food manufacturing. For stearic acid to become the primary replacement for TFA, it is essential that its physical properties and biological effects be well understood.  相似文献   

10.
The Chilean school population has shown remarkable changes in their eating habits, incorporating high fat content foods to their diet, which could explain the current high obesity rates. A great proportion of these foods uses industrial fats whit high content of saturated fatty acids (SFA) and potentially contains trans fatty acids (TFA) as a result of partial oil hydrogenation or as a natural form in ruminant animals fat. The purpose of this investigation was to determine fatty acid profile, including trans fatty acids, from food consumed by the Metropolitan Region school population. A food consumption survey was applied to 203 Metropolitan Region of Chile school-children, which consisted of questions about food consumption frequency and consumer preferences. Based on the results, ten types of food products were selected. Fat content, fatty acids profile, including trans fatty acid, were determinate by GLC according to the UNE 5509 Norm. Each analysis was carried out in duplicate and three samplings were performed. It was found that a great percentage of the analyzed foods showed low TFA content (<1%). However, some of them presented remarkable saturated fatty acids content, generating a PUFA/SFA ratio with poor fat nutritional quality. The low TFA concentration found in the food may be explained by a decrease in the use of hydrogenated fats, following PAHO/WHO recommendation, which are being applied in Chile.  相似文献   

11.
12.
Hydrogenation of sunflower and canola oils over a novel Pd-supported catalyst (pore size of 6.8 nm and BET specific surface area of 837 m2/g) was investigated and compared to commercial nickel catalyst. The formulated catalyst with Pd-loading of 1 wt%, supported on structured silica material was active and selective for the hydrogenation of sunflower and canola oils under mild process conditions. For both oils, the novel Pd supported catalyst exhibited a better selectivity than commercial Ni catalyst at a similar activity with a lower metal loading. For the same iodine value (IV) reduction, the Pd-catalyst produced less saturated fatty acids (SFA) and about the same level of trans fatty acids (TFA), but was more selective towards cis monoenes formation than Ni-catalyst. More importantly, this catalyst produced a reduced level of stearic acid, which at increased levels causes waxy mouth feel of the hydrogenated fat.  相似文献   

13.
Safflower oil-based oleogels were produced from beeswax and rice bran wax. Oleogels demonstrated higher oxidative stability than shortening at the cooking temperature. Peroxide values in shortening, rice bran wax oleogels, and beeswax oleogels samples were found in the range of 4.8–27.76, 13.21–20.45 and 4.30–7.72 meqO2kg−1 oil. Following oleogelation, there was no significant change in fatty acid composition of safflower oil. In addition, after baking process, the changes in the major fatty acids were not determined to be significant. Solid fat content ratios (carried out at 35°C) of rice bran wax oleogels, in beeswax oleogels and in shortening samples were defined in the range of 4.10%–7.70%, 0.80%–5.00%, and 9.61%, respectively. The highest oil binding capacity was revealed in beeswax oleogels with 99.93%–99.98%. The shortest crystallization time was determined as 3 min in oleogel containing 10% rice bran wax. Cakes consisted of oleogel were acceptable in terms of texture and sensory properties compared to cake produced with shortening. Sensory results revealed that some cakes produced with oleogels were found to be more acceptable as compared with control group samples. In this respect, oleogels produced with safflower oil-based beeswax and rice bran wax could be used instead of commercial solid fat widely used in the cake industry.  相似文献   

14.
In this study, we investigated the effect of monoacylglycerol (MAG) as a structuring agent on the physicochemical, microstructure and rheological properties of chicken fat. The fatty acid composition, oxidative stability, free fatty acids (FFA), slip melting point (SMP), solid fat content (SFC), kinetics of crystallization, microstructure and rheological properties of the samples were evaluated. The addition of MAG at a 0.5 % level did not affect the fatty acid composition, induction period of oxidation at 110 °C (IPox110), SFC curve or rheological properties of chicken fat (p > 0.05). However, structured samples containing 3.0 and 5.0 % MAG had higher saturated fatty acid (SFA) content, SFC, SMP, FFA content and IPox110 (p < 0.05). The addition of MAG led to a reduction in the IP of oxidation at 60 °C (IPox60) and increased the oxidation rate of fats, as measured by the Schaal oven test. Samples containing 3–5 % MAG had higher SFC content, higher loss, storage and complex moduli, higher complex viscosity, and a lower induction period of crystallization (IPcryst) and tan δ than chicken fat. Investigations by polarized light microscopy confirmed the presence of increased crystal content in samples containing higher MAG levels. These results show that structured chicken fats have the potential for application in the production of soft tub margarine and Iranian vanaspati.  相似文献   

15.
High-yield enzymatic glycerolysis of fats and oils   总被引:2,自引:0,他引:2  
Several triglyceride fats and oils were reacted with glycerol using lipase as catalyst. A batch system with magnetic stirring was used without the addition of any solvents or emulsifiers. In all cases a mixture of mono-, di- and triglycerides was obtained. However, the yield of monglyceride (MG) depended strongly on the reaction temperature: at higher temperatures approximately 30% MG was produced at equilibrium while at lower temperatures a yield of 65%–90% MG was obtained for most of the fats examined. The upper temperature limit below which a high MG yield could be attained was designated the critical temperature (Tc). The value of Tc depended on the fat type and was found to vary between 30°C and 46°C for naturally occurring hard fats. A high MG yield could not be obtained for fully hydrogenated tallow and lard under the conditions described here. Of the three liquid oils examined, rapeseed oil and olive oil had a Tc of 5°C and 10°C respectively whereas a high yield of MG could not be obtained with corn oil at 5°C or greater. The maximum yield of MG below Tc also depended on the fat type: the highest yields being obtained for olive oil (90%), palm stearin and milk fat (80%) and the lowest yield for palm oil (67%). In all cases a high yield of MG was accompanied by solidification of the reaction mixture. The effect of enzyme type on MG production was examined for palm oil and palm stearin and the effect of water concentration was examined for palm oil.  相似文献   

16.
There is current interest in reducing the trans fatty acids (TFA) in hydrogenated vegetable oils because consumption of foods high in TFA has been linked to increased serum cholesterol content. In the interest of understanding the TFA levels, hydrogenation was carried out in this work on soybean oil and cottonseed oil at two pressures (2 and 5 bar) and 100 °C using commercially available Ni, Pd, and Pt catalysts. The TFA levels and the fatty acid profiles were analyzed by gas chromatography. The iodine value of interest is ~70 for all-purpose shortening and 95–110 for pourable oil applications. In all cases, higher hydrogen pressures produced lower levels of TFA. In the range of 70–95 iodine values for the hydrogenated products, the Pt catalyst gave the least TFA, followed closely by Ni, and then Pd, for both oils. For all three catalysts at 2- and 5-bar pressures and 70–95 iodine values, cottonseed oil contained noticeably less TFA than soybean oil; this is probably because cottonseed oil contains a lower total amount of olefin-containing fatty acids relative to soybean oil. Approximate kinetic modeling was also done on the hydrogenation data that provided additional confirmation of data consistency.  相似文献   

17.
Fat blends, formulated by mixing a highly saturated fat (palm stearin or fully hydrogenated soybean oil) with a native vegetable oil (soybean oil) in different ratios from 10:90 to 75:25 (wt%), were subjected to chemical interesterification reactions on laboratory scale (0.2% sodium methoxide catalyst, time=90 min, temperature=90°C). Starting and interesterified blends were investigated for triglyceride composition, solid fat content, free fatty acid content, and trans fatty acid (TFA) levels. Obtained values were compared to those of low- and high-trans commercial food fats. The interesterified blends with 30–50% of hard stock had plasticity curves in the range of commercial shortenings and stick-type margarines, while interesterified blends with 20% hard stock were suitable for use in soft tubtype margarines. Confectionery fat basestocks could be prepared from interesterified fat blends with 40% palm stearin or 25% fully hydrogenated soybean oil. TFA levels of interesterified blends were low (0.1%) compared to 1.3–12.1% in commercial food fats. Presented at the 88th AOCS Annual Meeting and Expo, May 11–14, 1997, Seattle, Washington.  相似文献   

18.
Enzymatic synthesis of trans-free structured margarine fat analogues from stearidonic acid (SDA) soybean oil and high stearate soybean oil was optimized using response surface methodology. The independent variables considered were the substrate molar ratio (2–5), temperature (50–65 °C), time (6–22 h), and enzymes (Lipozyme® TLIM and Novozym® 435). The dependent variables were mol% stearic acid incorporation and mol% SDA content. A good-fit model was constructed using regression analysis with backward elimination and verified by a Chi-square test. Desirable and optimal products composition were achieved at 50 °C, 18 h, 2:1, using Lipozyme TLIM, with 15.6 mol% stearic acid and 9.2 mol% SDA in the product and at 58 °C, 14 h, 2:1, using Novozym 435, with 14.8 mol% stearic acid and 6.4 mol% SDA. Using optimal conditions, structured lipids (SL) were synthesized in a 1 L stir-batch reactor and free fatty acids removed by short-path distillation. SL were characterized for their fatty acid profile, sn-2 positional fatty acids, triacylglycerol profile, polymorphism, thermal behavior, and solid fat content. The SL had a desirable fatty acid profile, physical properties, and a suitable β′ polymorph content. These SL could be used as margarine fat analogues and an alternative to partially hydrogenated fat.  相似文献   

19.
Nineteen commercial samples of vegetable oils and margarines marketed in Belgium (nine margarines, nineteen vegetable oils), Hungary (seven margarines) and Great-Britain (three margarines) were analyzed by gas-liquid chromatography for their trans-fatty acid (TFA) content. For the vegetable oil samples under study, the TFA content ranged from 0.0–4.6% (mean: 1.1%, S.D.: 1.1%). Trans-isomers in these samples were almost exclusively C 18:2 and C 18:3 isomers formed during high temperature refining. Trans-isomers of the margarines were mainly C 18:1 isomers formed during hydrogenation. For the Belgian resp. Hungarian samples mean trans-values of 6.36% (S.D. = 6.20%) resp. 14.06% (S.D. = 7.59%) expressed on fat basis were established. From these figures the average daily intake of TFA from margarines resp. vegetable oils by the Belgian population was calculated at 1.1 resp. 0.1g/person/day. When so-called zero-trans margarines (±0.5% TFA) are consumed, the trans-intake can be reduced to about 0.1g/person/day.  相似文献   

20.
A novel process is proposed to turn soft gelled emulsions containing saturated monoglyceride (MG), sunflower oil, and water into a fat material with the typical water content (20 g/100 g) and rheological properties of roll-in margarine. A gentle drying procedure at 30 °C is proposed to allow partial water removal from the emulsions, without causing phase separation. Upon water removal, the soft emulsion, initially stabilized by a highly hydrated liquid crystalline lamellar phase of MG, converts into a high internal phase oil–water emulsion (HIPE) stabilized thanks to the presence of MG crystals around gelled oil particles, which are interconnected via polar groups of MG. HIPE at the highest MG content (13.7 g/100 g) shows rheological properties (Gʹ = 4.6 × 105 Pa, critical stress = 634 Pa) comparable to those of commercial roll-in margarine and is successfully used in baking trials of puff pastry. Practical Applications: The last years have seen an increasing demand for strategies for the nutritional improvement of lipid-containing foods, due to the emerging health concern related to the consumption of unbalanced saturate/unsaturated fats. Moreover, sustainability issues have arisen due to the abundant use of tropical fats in foods. However, the unique technological and sensory properties of fats make this task very challenging, especially considering the production of laminated products requiring the use of plastic fat materials with peculiar rheological properties. The results obtained in this study are very promising, as they show that the novel fat can be used as an alternative to traditional laminating margarine.  相似文献   

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