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1.
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   

2.
Trans Fatty Acids in Foods The fatty acid compositions of the fat in 196 german food samples were analyzed with emphasis on trans components by gas liquid chromatograghy. The range of trans fatty acids (weight percent of methyl esters) in several foods was: margarines 0.6 - 23.5%, shortenings 0.1 - 31.8%, french fried potatoes 508 - 32.8%, cakes and cookies 0 - 15.5%, candies and frostings 0.2 - 15.7%, Crisps and other snacks 0.1 - 20.2%, animal and dairy fats from ruminants. 1.5 - 10.6%, other meat products animals and sausages less than 1%. Teh composition of trans fatty acids differed between hydrogenated fats and ruminant fats. Food processing (except hydrogenation) did not substantially alter the fatty acid composition. The daily intake of trans fatty acids in Germany was estimated by the National Consumption Assay. women consumed 3.4 g/day and men 4.1 g/day. Hydrogenated fats and ruminant fats contributed to the consumption nearly equally. Trans fatty acids influence the plasma lipoprotein levels similarly to saturated fatty acids. The trans fatty acids appear mostly as monounsaturated fatty acids in food composition tables. It seems necessary to distinguish between cis and trans isomers.  相似文献   

3.
Twenty-seven commercial bakery products marketed in Belgium were analyzed by gas-liquid chromatography for their trans (TFA) and polyunsaturated fatty acid (PUFA) content. The mean PUFA level for the bakery fats in our study was 8.85% (S.D. = 9.90%) and the TFA content ranged from 0.0–18.81% (mean = 5.99%; S.D. = 5.02%). The unfavourable fatty acid profile of most of the analyzed bakery fats can be explained by the frequent use of animal fat and partially hydrogenated oils. The average daily intake of TFA from bakery products by the Belgian population was calculated at 0.43g/person/day. As it is expected that their consumption will increase in the future, lower TFA levels in bakery fats are necessary to avoid that these products become a more important dietary source of TFA.  相似文献   

4.
Nutritional Properties of Animal Fats Dietary fat plays two roles, as a carrier of energy, and, in the form of essential fatty acids, as an indispensable component of food. Animal fats can meet both requirements. Since fats are greatly accepted by the people due to their taste, the fat consumption by the entire population has been very high. High fat consumption are believed to have resulted in increased level of cholesterol and premature occurrence of coronary diseases. Increase in the incidence of deaths by coronary diseases has drawn attention to the nutritional properties of dietary fats, which affect the level of cholesterol. It has been established that saturated fatty acids in foods raise the level of serum cholesterol, whereas polyunsaturated fatty acids lower it. However, with diets of relatively low fat content the ratio of saturated to polyunsaturated fatty acids is not so significant with regard to level of serum cholesterol as with high-fat diets.  相似文献   

5.
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   

6.
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   

7.
A total of 82 dietary fats sold on the Bulgarian market in the period 1995—2000 were analyzed. The samples included 68 table margarines (50 of which were imported), 10 frying fats (6 imported) and 4 salad dressings (all imported). A validated analytical method, thin‐layer chromatography‐AgNO3‐densitometry, was used. It enabled direct determination of all fatty acid groups, differing by degree of unsaturation and double bonds geometry. Low levels of trans fatty acids (TFA) down to 0.1% of the total for mono trans‐trienoic (Tcct) and mono trans‐dienoic (Dct), and down to 0.2% for trans‐monoenoic (Mt) were quantitated, with an error under 3% and a standard deviation of 0.1—1.5. The total content of TFA in table margarines varied from 0 to 26.9% with a mean value of 8.6 ± 7.2% for imported and 1.6 ± 3.4% for Bulgarian samples. Saturated fatty acids (SFA) content varied from 11.5 to 45.7%, with a mean value of 25.4 ± 5.7% for imported and 26.9 ± 5.2% for Bulgarian margarines. A general trend of lower levels of TFA and SFA in imported margarines was observed over the studied period. Additionally, the content of individual saturated fatty acids was determined by gasliquid chromatography in 37 of all studied samples.  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.
Fats in the diet     
Fats are important constituents of the human diet since on the one hand, they contribute to the caloric density of the diet, and on the other, they serve as vehicles of essential nutrients such as linoleic and alpha-linolenic acids, as well as fat-soluble vitamins. The existence of human populations subsisting on diets with values as low as 10% or more than 50% of the calories represented by fats, has been documented, demonstrating the great adaptability of man to a wide availability of this type of food. Nevertheless, extensive epidemiological and experimental research in relation to a frequent degenerative diseases of man, arteriosclerosis, have consistently demonstrated that the proportion of saturated fats in the diet has a positive correlation with the frequency of these alterations. Mortality and fat availability in Latin America is consistent with these results. In consequence, and taking into consideration the present level of fat availability in the Region, we propose that no more than 25% of the caloric requirement should be covered by fats. Additionally, this amount of fat should have equal proportions of saturated, monounsaturated and polyunsaturated fatty acids. Cholesterol, which is contained in animal fats, is not a necessary nutrient for humans, so that no minimum consumption needs to be established. Daily ingestion of cholesterol should be restrained to no more than 100 mg/1,000 calories. Introduction of new fatty foods for human consumption should be preceded by a thorough investigation of the metabolic consequences.  相似文献   

10.
Recent research results mandate a careful re‐evaluation of the widespread belief that dietary saturated fat is harmful. Specifically, multiple recent reports find no association between dietary saturated fat intakes and cardiovascular disease (CVD). There is, however, a consistent pattern of increased risk for both CVD and type‐2 diabetes associated with increased levels of saturated fatty acids (SFA) in circulating lipids. This raises the important question as to what contributes to increased levels of saturated fat in the blood? Whereas dietary intake of saturated fats and serum levels of SFA show virtually no correlation, an increased intake of carbohydrate is associated with higher levels of circulating SFA. This leads to the paradoxical conclusion that dietary saturated fat is not the problem; rather it's the over‐consumption of carbohydrate relative to the individual's ability to metabolize glucose without resorting to de novo lipogenesis. From this perspective, insulin resistant states like metabolic syndrome and type‐2 diabetes can be viewed as carbohydrate intolerance, in which a high carbohydrate intake translates to increased serum SFA and therefore increased risk.  相似文献   

11.
During cooking oils and fats are exposed to high temperatures that may affect the nutritional quality of foods that are prepared in this way. Concerns have been raised about the degradation of polyunsaturated fatty acids and the formation of potentially harmful compounds during deep frying, but relatively little is known about these changes in other cooking processes. In the present study sponge cakes and fried potatoes were prepared via standardised baking and shallow frying procedures by using different oils and fats (sunflower oil, rapeseed oil, various margarines or butter). The effect of cooking on the retention of two essential fatty acids (linoleic acid and α-linolenic acid) and the formation of trans fatty acids (TFA) and polymerised triacylglycerols (PTG) was evaluated by analyzing fat extracted from the cooked food. It was found that over 95 % of essential fatty acids were retained upon completion of both cooking techniques. The formation of TFA was not significant. Polymerisation was noticeable only in shallow frying, although the final levels of PTG were negligible (<1.3 %). Overall, in contrast to deep frying, oil-based media high in polyunsaturated fatty acids seem to be a good alternative for domestic cooking techniques as they increase the nutritional value of the prepared food.  相似文献   

12.
Partially hydrogenated oils (PHO), the products of incomplete catalytic hydrogenation of food oils, have been widely employed by the food industry for more than a century. Their exceptional stability and technologic characteristics made them the preferred choice for the production of several food products including margarines, bakery goods, and frying oils. Some of these highly prized characteristics were provided by the high content in trans fatty acids (TFA), defined as fatty acids with one or more isolated double bond in trans configuration. The discovery of negative health effects associated with dietary intake of TFA triggered world-wide a wave of regulatory actions aimed to curb their consumption. PHO became the main target of most campaigns aimed to reduce consumption of TFA, and their fortune in the food industry progressively faded. At the 2017, AOCS Annual Meeting in Orlando, a group of experts from regulatory agencies and industry from North America and Europe met to discuss the current status of government regulations and industry adaptations regarding the productions and use of PHO. The discussion was enriched by including the impact on fats and oils production of the 2016 amendment of the Toxic Substances Control Act of 1976 (TSCA). The present publication may not include all regulatory changes that took place after this symposium, in 2017.  相似文献   

13.
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   

14.
Kerry J. Ayre  A. J. Hulbert 《Lipids》1997,32(12):1265-1270
Typically, athletes are advised to increase their consumption of carbohydrates for energy and, along with the general population, to reduce consumption of saturated fats. It is now recognized that fats are not identical in their influence on metabolism, and we argue that the composition of the polyunsaturated fat component should not be ignored. The aim of this study was to manipulate the dietary fatty acid profile in a high-carbohydrate diet in order to investigate the effect of dietary polyunsaturates on submaximal endurance performance in rats. Rats were fed one of three isoenergetic diets containing 22 energy percentage (E%) fat for 9 wk. The diets comprised an essential fatty acid-deficient diet (containing mainly saturated fatty acids); a diet high in n-6 fatty acids, High n-6; and a diet enriched with n-3 fatty acids, High n-3. Submaximal endurance in rats fed the High n-3 diet was 44% less than in rats fed the High n-6 diet (P<0.02). All rats were then fed a standard commercial laboratory diet for a 6-wk recovery period, and their performances were reevaluated. Although endurance in all groups was lower than at 9 wk, it was again significantly 50% lower in the High n-3 group than the High n-6 group (P<0.005). Although n-3 fats are considered beneficial for cardiovascular health, they appear to reduce endurance times, and their side effects need to be further investigated.  相似文献   

15.
In the present study, 122 food samples from the German food market were analysed for their C18:1 trans fatty acid (TFA) content and profile. A particular focus of the survey were baked and fried foods. TFA analysis was performed by means of silver ion SPE (Ag+‐SPE) in combination with high‐resolution GC (HRGC‐FID). Overall, 51 bakery product samples were analysed of which 25 samples were prepacked bakery products purchased from local retail stores and 26 samples of unpacked bakery products purchased from local bakery shops. In addition, 14 French fries samples obtained from small local fast food restaurants as well as from internationally operating fast food chains, 27 potato and tortillas chips, 15 instant soups as well as 15 dry culinary sauces were analysed. The highest amounts of C18:1 TFA isomers were found in deep‐fried bakery products. Prepacked branded cookies and biscuits on the other hand contained only negligible C18:1 TFA amounts. Regarding their C18:1 trans isomer profile most deep‐fried bakery products exhibited a Gaussian‐distributed isomer profile. The analysed prepacked croissants, cookies and biscuits contained predominantly ruminant TFA (TFA) as suggested by the presence of vaccenic acid (C18:1 trans 11), which was the major C18:1 TFA isomer in these products. All non‐bakery samples (n = 71) contained less than 3 g C18:1 TFA per 100 g fat. In conclusion, TFA still occur in considerable amounts in a few German food products, especially in some deep‐fried bakery products (‘Berliner’ type of doughnuts). Practical applications: Trans fatty acids, in particular the trans octadecenoic fatty acid isomers (C18:1), are generally considered from the nutritional point of view as undesirable food components due to their negative health effects. Tremendous efforts have been made by major food processors in order to decrease or even eliminate the presence of TFA in some foodstuffs (e.g. in margarines in European countries). However, some food processors of other food sectors are still applying oils and fats containing partially hydrogenated vegetable oils, whereas others within the same food category have already switched their processing conditions and/or raw materials towards TFA alternatives. Therefore, actual TFA data of foodstuffs determined by means of state‐of‐the‐art analytical procedures (Ag+‐SPE in combination with GC‐FID) is necessary to detect areas of further improvement in the food supply chain and to provide data for an update of dietary TFA intake.  相似文献   

16.
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   

17.
TAGs play an important role in determining the functional properties of fat‐based food products such as margarines, chocolate, and spreads. Nowadays, special attention is given to the role of the TAG structure and how it affects functional properties such as mouth feel, texture, and plasticity. Key to this research is the need to develop more healthy fats with a reduced level of trans and saturated fatty acids (SFAs), while maintaining the desired properties. In this study, fat blends with identical levels of SFA (50%) but differing in the ratio asymmetric/symmetric blends were evaluated by pulsed NMR and texturometry as a function of storage time and storage temperature. A higher trisaturated TAG content gave rise to a higher solid fat content (SFC) at higher temperature and a lower SFC at lower temperature for both palmitic and stearic based blends. On the other hand, the effect of symmetry on the SFC‐profile of the blends was only clear for the stearic based blends. At lower temperatures, the SFC of symmetric TAG based blend (blend SM) was markedly lower than that of asymmetric TAG based blend (blend iS). However, from 30°C onwards, the SFC of blend SM was clearly higher than that of blend iS. The microscopic analyses revealed a denser crystal network for a higher degree of trisaturated TAG and for symmetric stearic based blends. Moreover, some blends showed a clear evolution of the microstructure during storage with smaller crystals transforming into larger ones. Finally, texture analyses demonstrated the importance of the crystallization and storage temperature on the hardness of the blends.  相似文献   

18.
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   

19.
气相色谱法测定食品油脂中的十八碳反式脂肪酸   总被引:1,自引:0,他引:1  
反式脂肪酸是在油脂的加氢反应或高温精炼过程中伴随产生的一类不饱和脂肪酸,过多的食用这些成分可能会对人体健康产生危害。食品油脂中以十八碳反式脂肪酸最为常见。采用气相色谱法对食品中十八碳反式脂肪酸的检测进行了实验摸索,获得了一套准确度高、精确度好的方法,可应用于日常监督检测。  相似文献   

20.
Changes in household food availability from 1988-1997 obtained in a representative sample of Metropolitan Santiago were assessed; and related to observed changes in the epidemiological profile. We evaluated expenditures in food and beverages from the IV and V Household Expenditure Surveys conducted every 10 years by the National Institute of Statistics to calculate the Consumer Price Index. Food items were similarly grouped and expenditures from both surveys adjusted to concordance by assigning prices according to of food; the units consumed outside and at home were determined. Food expenditures increased, leading to greater food availability in all households and income categories; the increment was largest in the poorest quintiles. Apparent consumption of processed cereals, pastries and baked goods, poultry and pork, processed dairies, beverages and juices, dressings and mayonnaise, pre cooked meals and meals consumed "out of home" increased. Fish, vegetables and fruits increased slightly with a concomitant decrease in legumes. The present dietary pattern is also characterized by a greater availability of animal food products and processed foods; increased energy density, fat and saturated fat energy, sugars and high glycemic index foods; lower in phytochemicals, antioxidants, dietary fiber and omega-3 fatty acids. These changes are probably having a significant impact on the epidemiological and nutritional profile of the country; as manifested by an epidemic increase in obesity and chronic disease burden related to diet and physical inactivity.  相似文献   

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