Fatty Acid Composition Of Foods Research Articles

Влияние экспрессии L-FABP и жирнокислотного состава пищи на состояние липидного метаболизма больных с разной степенью диабетической ретинопатии и сахарным диабетом 2-го типа

Актуальность. Чрезмерный уровень жирных кислот (ЖК) является токсичным для клеток, поэтому экс­прессию протеина FABP рассматривают как защитный механизм, связывающий ЖК и направляющий их в соответствующие сайты внутриклеточной утилизации и окисления или накопления. Повышение в плазме содержания свободных ЖК играет ключевую роль в развитии сахарного диабета и его осложнений, а также инсулинорезистентности. Цель работы: изучение влияния экспрессии L-FABP и жирнокислотного состава пищи на состояние липидного метаболизма у пациентов с разной степенью диабетической ретинопатии (ДР) и сахарного диабета 2-го типа (СД2). Материалы и методы. Исследование включало 76 больных (76 глаз) с СД2, у которых по результатам офтальмологического обследования выявлена разная степень ДР. Контрольную группу (КГ) составили 23 лица без СД, сопоставимые с пациентами по полу, возрасту, индексу массы тела. Прогрессирование ДР определяли по шкале ETDRS, выделили 3 группы: ДР-1 группа (18 больных, 18 глаз) — пациенты с легкой, умеренной и тяжелой непролиферативной ДР; ДР-2 группа (27 больных, 27 глаз) — пациенты с легкой, умеренной и высокого риска пролиферативной ДР; ДР-3 группа (31 больной, 31 глаз) — пациенты с прогрессирующей пролиферативной ДР. Изучение спектра ЖК в мембранах эритроцитов проводили методом газожидкостной хроматографии. Содержание L-FABP определяли в сыворотке крови методом ELISA. Для изучения особенностей питания была разработана анкета, на вопросы которой предлагалось ответить всем исследуемым. Результаты. Состояние липидного метаболизма у пациентов с ДР и СД2 характеризовалось существенной разницей содержания ЖК в мембранах эритроцитов по сравнению с группой здоровых лиц с достоверным повышением степени «насыщенности». В группах ДР-1 и ДР-3 наблюдалось повышение в 1,5–2 раза (Р < 0,05) содержания насыщенных жирных кислот (НЖК) и снижение ненасыщенных жирных кислот (ННЖК) за счет полиненасыщенных жирных кислот, а в группе ДР-2 — практически равное содержание НЖК и ННЖК. С прогрессированием ДР выявлена тенденция к снижению содержания миристиновой и арахидоновой ЖК и повышение стеариновой и олеиновой ЖК. Употребление в пищу продуктов-источников различных типов ЖК по рассчитанному показателю «рациональность потребления продуктов», полученному на основании анализа анкет питания, не отличалось в группах здоровых лиц и у пациентов с разной степенью ДР. У пациентов с ДР и длительным СД2 мы обнаружили достоверное повышение сывороточного уровня L-FABP. В группе ДР-1 L-FABP был в 1,5 раза (Р < 0,05) выше, чем в КГ. В группе ДР-2 наблюдали незначительное уменьшение показателя, но он оставался в 1,3 раза больше КГ, а в группе ДР-3 снова обнаружили повышение относительно КГ в 1,7 раза. Можно предположить, что уменьшение экспрессии L-FABP в группе ДР-2 отображает адаптацию организма к высокому уровню ЖК плазмы и имеет сдерживающее влияние на развитие и прогрессирование ДР. Выводы. Проведенное исследование отображает регуляторную роль L-FABP как важного фактора эндогенной регуляции липидного гомеостаза на фоне отсутствия существенных экзогенных воздействий пищевой нагрузки на метаболизм липидов организма у больных с ДР и СД2.

Omega-3 Fatty Acids and Vitamin D Decrease Plasma T-Tau, GFAP, and UCH-L1 in Experimental Traumatic Brain Injury.

Traumatic brain injury (TBI) results in neuronal, axonal and glial damage. Interventions targeting neuroinflammation to enhance recovery from TBI are needed. Exercise is known to improve cognitive function in TBI patients. Omega-3 fatty acids and vitamin D reportedly reduce inflammation, and in combination, might improve TBI outcomes. This study examined how an anti-inflammatory diet affected plasma TBI biomarkers, voluntary exercise and behaviors following exposure to mild TBI (mTBI). Adult, male rats were individually housed in cages fitted with running wheels and daily running distance was recorded throughout the study. A modified weight drop method induced mTBI, and during 30 days post-injury, rats were fed diets supplemented with omega-3 fatty acids and vitamin D3 (AIDM diet), or non-supplemented AIN-76A diets (CON diet). Behavioral tests were periodically conducted to assess functional deficits. Plasma levels of Total tau (T-tau), glial fibrillary acidic protein (GFAP), ubiquitin c-terminal hydrolase L1 (UCH-L1) and neurofilament light chain (NF-L) were measured at 48 h, 14 days, and 30 days post-injury. Fatty acid composition of food, plasma, and brain tissues was determined. In rats exposed to mTBI, NF-L levels were significantly elevated at 48 h post-injury (P < 0.005), and decreased to levels seen in uninjured rats by 14 days post-injury. T-tau, GFAP, and UCH-L1 plasma levels did not change at 48 h or 14 days post-injury. However, at 30 days post-injury, T-tau, GFAP and UCH-L1 all significantly increased in rats exposed to mTBI and fed CON diets (P < 0.005), but not in rats fed AIDM diets. Behavioral tests conducted post-injury showed that exercise counteracted cognitive deficits associated with mTBI. The AIDM diets significantly increased docosahexaenoic acid levels in plasma and brain tissue (P < 0.05), and in serum levels of vitamin D (P < 0.05). The temporal response of the four injury biomarkers examined is consistent with studies by others demonstrating acute and chronic neural tissue damage following exposure to TBI. The anti-inflammatory diet significantly altered the temporal profiles of plasma T-tau, GFAP, and UCH-L1 following mTBI. Voluntary exercise protected against mTBI-induced cognitive deficits, but had no impact on plasma levels of neurotrauma biomarkers. Thus, the prophylactic effect of exercise, when combined with an anti-inflammatory diet, may facilitate recovery in patients with mTBI.

Omega-3 Fatty Acids and Vitamin D Decrease Plasma T-tau, GFAP, and UCH-L1 in Experimental Traumatic Brain Injury

ObjectivesTraumatic brain injury (TBI) results in neuronal, axonal and glial damage. Interventions targeting neuroinflammation to enhance recovery from TBI are needed. Exercise is known to improve cognitive function in TBI patients. Omega-3 fatty acids and vitamin D reportedly reduce inflammation, and in combination, might improve TBI outcomes. This study examined how an anti-inflammatory diet affected plasma TBI biomarkers, voluntary exercise and behavior following exposure to mild TBI (mTBI). MethodsAdult, male rats were individually housed in cages fitted with voluntary running wheels and daily running distance was recorded during the study. A modified weight drop method induced mTBI, and during 30 days post-injury, rats were fed diets supplemented with omega-3 fatty acids and vitamin D3 (AIDM diet), or non-supplemented AIN-76A diets (CON diet). Behavioral tests were periodically conducted to assess functional deficits. Plasma levels of Total tau (T-tau), glial fibrillary acidic protein (GFAP), ubiquitin c-terminal hydrolase L1 (UCH-L1) and neurofilament light chain (NF-L) were measured at 48 h, 14 d and 30 d post-injury. Fatty acid composition of food, plasma and brain tissues was determined. ResultsIn rats exposed to mTBI, NF-L levels were significantly elevated at 48 h post-injury (P < 0.005), and decreased to levels seen in uninjured rats by 14 d post-injury. T-tau, GFAP and UCH-L1 plasma levels did not change at 48 h or 14 d post-injury. However, at 30 d post-injury, T-tau, GFAP and UCH-L1 all significantly increased in rats exposed to mTBI and fed CON diets (P < 0.005), but not in rats fed AIDM diets. Behavioral tests conducted post-injury showed that exercise counteracted cognitive deficits associated with mTBI. The AIDM diets significantly increased docosahexaenoic acid levels in plasma and brain tissue (P < 0.05), and in serum levels of vitamin D (P < 0.05). ConclusionsThe anti-inflammatory diet significantly altered the temporal profiles of plasma T-tau, GFAP and UCH-L1 following mTBI. Voluntary running exercise protected against mTBI-induced cognitive deficits, but had no impact on plasma levels of neurotrauma biomarkers. Thus the prophylactic effect of exercise, when combined with an anti-inflammatory diet, may facilitate recovery in patients with mTBI. Funding SourcesU.S. Army MRDC.

Impact assessment of the TFA regulation on fatty acid composition of foods in Hungary

Abstract Trans fatty acids are formed during the industrial processing of food, and are proven to be harmful for the human body. They have been associated with increased risk of cardiovascular disease, abdominal obesity, diabetes, and certain types of cancer. Decree 71/2013. (XI. 20.) of the Ministry of Human Capacities, which has been in force since 2014, defines the highest permitted amount of trans fats in food products placed on the market in Hungary. The impact of the decree on the industrially produced trans fatty acids (iTFA) availability and population intake was assessed in 2017. Results demonstrated that iTFA were replaced by other fatty acids due to the legislation. In 2019, we investigated food groups which had high measured TFA content before the regulation entered into force and compared the total fat and fatty acid profiles to the same brand or similar products being on the market afterwards. In collaboration with the World Health Organization, this was the first assessment to determine to which extent manufacturers increased saturated fat (SFA) content of foodstuffs to reduce iTFA content. In those product groups, which were identified as significant food sources of iTFA before introducing the regulation (biscuits, coffee creamers and flavorings, sweets, bakery products, confectionary, wafers, margarines) we found no significant changes in the total fat content, while in most foodstuffs the average proportion of SFA was higher after reformulation, as iTFA were mainly substituted with SFA in 61% of the products, with cis-MUFA in 25% and cis-PUFA in 14% of the products, respectively. Evidence from this analysis supports concerns that eliminating iTFA in certain foodstuffs leads to unwanted substitution with saturated fat, hence reducing the possible health benefits. Given the high SFA intake and the unfavourable cardiovascular statistics in Hungary, the consumption frequency and portion size control of these products are advised. Key messages Monitoring the changes of food composition is important in order to evaluate the effect of the regulation. Manufacturers should be encouraged to reduce the SFA content to a technologically feasible level.

Stability of oil-in-water emulsions performed by ultrasound power or high-pressure homogenization.

Emulsifiers are added to enhance product stability to obtain a satisfactory shelf-life. For this reason, stable emulsions that do not form peroxides nor change the fatty acid composition of food, as well as safe treatments to obtain them, are aspects of utmost importance. High-pressure homogenization is a conventional approach to prepare emulsions because of its high efficiency. In addition, the beneficial effects of ultrasound on the processing efficiency are known. Therefore, the impact of high-pressure homogenization (30 MPa, 50M Pa) or ultrasound power (270 W) on the emulsion stability and emulsifying properties of 5% coconut oil-in-water emulsion were discussed in this study. The complexes (3:7and 4:6, by weight) of propylene glycol alginate and xanthan gum were selected as emulsifier. The apparent viscosity, particle size and distribution, emulsifying properties and ζ–potential of 5% coconut oil-in-water emulsion before and after ultrasound treatment or high-pressure homogenization were investigated and compared. The micro structure of the emulsion was observed under the fluorescence microscope. The experimental results showed that both high-pressure homogenization and ultrasonic treatment effectively reduced the apparent viscosity, average droplet size and narrowed the distribution range of the emulsion, compared with the pre-emulsion. However, aggregation in the emulsion appeared only after being subjected to high-pressure homogenization, while the emulsion made by the ultrasound treatment remained stable during 30 days storage. In conclusion, this study provides valuable information regarding emulsion preparation methods that can be feasible in food and beverage industries, demonstrating a better performance of ultrasound in optimizing and extending food shelf-life in food and beverage industries.

Fatty Acid Composition of Ostrich (Struthio Camelus) Abdominal Adipose Tissue

Abstract Fatty acid composition of foods has a great impact on nutrition and health. Therefore, thе determination and knowledge of the fatty acid composition of food is very important for nutrition. Due to the high nutritional characteristics of ostrich meat and its products, the research determining their quality is of topical interest. The aim of the present investigation was the determination of fatty acid composition of ostrich adipose tissue. The content of fatty acids was determined according to AOAC Official Methods of Analysis and determination was performed using a gas chromatograph with a flame-ionization detector (GC-FID). The results are expressed as a percentage of the total content of fatty acids. The method was validated and whereupon the following parameters were determined: linearity, precision, recovery, limit of detection and limit of quantification. The repeatability was within of 0.99 to 2.15%, reproducibility from 2.01 to 4.57%, while recovery ranged from 94.89 to 101.03%. According to these results, this method is accurate and precise and can be used for analysis of fatty acids in foods. It was concluded that the content of saturated fatty acids (SFA) accounted 34.75%, of monounsaturated fatty acids (MUFA) 38.37%, of polyunsaturated fatty acids (PUFA) 26.88%, of total unsaturated fatty acids (UFA) 65.25% and of desirable fatty acids (DFA) (total unsaturated + stearic acid) 70.37% of the analysed samples. The ratio polyunsaturated/saturated fatty acids accounted 0.77. The most present fatty acid is the oleic (C18:1n9c) with 28.31%, followed by palmitic (C16:0) with 27.12% and linoleic (C18:2n6c) acid with 25.08%. Other fatty acids are contained in significantly lower quantities.

Endocannabinoid signaling and its regulation by nutrients.

Diet plays a central role in maintaining health throughout life and a controlled food intake is associated to a reduced risk of certain diseases. A proper diet should include vitamins, minerals, carbohydrates, proteins, and fats that have to be optimally balanced in order to exert their physiological functions. The endogenous ligands of type-1 and type-2 cannabinoid receptors, N-arachidonoyl-ethanolamine and 2-arachidonoylglycerol, are arachidonic acid (AA) derivatives whose levels are regulated by the activity of metabolic enzymes, as well as by AA availability. Since the only sources of AA in mammals are diet and the enzymatic production in the liver from shorter-chain essential fatty acids like linoleic acid, it is realistic to hypothesize that endocannabinoid levels might be modulated by fatty acid composition of food. Therefore, in this review we summarize literature data indicating that endocannabinoid levels, and hence their activity at cannabinoid receptors, might be modulated by food composition. We focused our attention on dietary fatty acid content, and on type and esterified form of fatty acids in the different diets.

Fatty acids in mountain gorilla diets: Implications for primate nutrition and health

Little is known about the fatty acid composition of foods eaten by wild primates. A total of 18 staple foods that comprise 97% of the annual dietary intake of the mountain gorilla (Gorilla beringei) were analyzed for fatty acid concentrations. Fruits and herbaceous leaves comprise the majority of the diet, with fruits generally having a higher mean percentage of fat (of dry matter; DM), as measured by ether extract (EE), than herbaceous leaves (13.0% ± SD 13.0% vs. 2.3 ± SD 0.8%). The mean daily EE intake by gorillas was 3.1% (DM). Fat provided ≈14% of the total dietary energy intake, and ≈22% of the dietary non-protein energy intake. Saturated fatty acids accounted for 32.4% of the total fatty acids in the diet, while monounsaturated fatty acids accounted for 12.5% and polyunsaturated fatty acids (PUFA) accounted for 54.6%. Both of the two essential PUFA, linoleic acid (LA, n-6) and α-linolenic acid (ALA, n-3), were found in all of the 17 staple foods containing crude fat and were among the three most predominant fatty acids in the diet: LA (C18:2n-6) (30.3%), palmitic acid (C16:0) (23.9%), and ALA (C18:3n-3) (21.2%). Herbaceous leaves had higher concentrations of ALA, while fruit was higher in LA. Fruits provided high amounts of fatty acids, especially LA, in proportion to their intake due to the higher fat concentrations; despite being low in fat, herbaceous leaves provided sufficient ALA due to the high intake of these foods. As expected, we found that wild mountain gorillas consume a diet lower in EE, than modern humans. The ratio of LA:ALA was 1.44, closer to agricultural paleolithic diets than to modern human diets.

Fatty Acid Composition at the Base of Aquatic Food Webs Is Influenced by Habitat Type and Watershed Land Use

Spatial variation in food resources strongly influences many aspects of aquatic consumer ecology. Although large-scale controls over spatial variation in many aspects of food resources are well known, others have received little study. Here we investigated variation in the fatty acid (FA) composition of seston and primary consumers within (i.e., among habitats) and among tributary systems of Lake Michigan, USA. FA composition of food is important because all metazoans require certain FAs for proper growth and development that cannot be produced de novo, including many polyunsaturated fatty acids (PUFAs). Here we sampled three habitat types (river, rivermouth and nearshore zone) in 11 tributaries of Lake Michigan to assess the amount of FA in seston and primary consumers of seston. We hypothesize that among-system and among-habitat variation in FAs at the base of food webs would be related to algal production, which in turn is influenced by three land cover characteristics: 1) combined agriculture and urban lands (an indication of anthropogenic nutrient inputs that fuel algal production), 2) the proportion of surface waters (an indication of water residence times that allow algal producers to accumulate) and 3) the extent of riparian forested buffers (an indication of stream shading that reduces algal production). Of these three land cover characteristics, only intense land use appeared to strongly related to seston and consumer FA and this effect was only strong in rivermouth and nearshore lake sites. River seston and consumer FA composition was highly variable, but that variation does not appear to be driven by the watershed land cover characteristics investigated here. Whether the spatial variation in FA content at the base of these food webs significantly influences the production of economically important species higher in the food web should be a focus of future research.

Differences in fatty acid composition of food and tissues of grayling from the Yenisei River

Differences in fatty acid composition of food and tissues of grayling from the Yenisei River

Impact of fatty acid food reformulations on intake of Dutch young adults

Background The Dutch ‘Task Force for the Improvement of the Fatty Acid Composition’ initiated fatty acid reformulations in branches using vegetable oils and fats to reduce the trans(TFA) and saturated fatty acid (SFA) content of foods.Objective This study estimates the impact of recent reformulations in the task force food groups by estimating changes in median intake of TFA and SFA in Dutch young adults.Methods This is a modelling study with food consumption data of young adults. Intakes were estimated before reformulation using food composition data of 2001 as a reference and while including most recent fatty acid composition of foods for task force food groups. Food composition of other foods and food consumption was assumed unchanged.Results Average TFA intake signifi cantly decreased from 1.0 E% in the reference to 0.8 E% in the reformulation scenario. Pastry, cakes and biscuits, and snacks contributed most to the decrease of TFA. Estimated SFA intake did not change. When solid baking and spreading fats were additionally replaced with fl uid ones, SFA intake decreases from 12.9 E% to 12.1 E%.Conclusion Fatty acid reformulation in the task force food groups contributed to reductions in TFA intake. For further reductions in SFA intake a different food choice is primordial.

Growth, survival and fatty acid composition ofRhamdia quelen(Quoy and Gaimard, 1824) larvae fed on artificial diet alone or in combination withArtemianauplii

Black catfish (Rhamdia quelen) is a species of interest for aquaculture in Brazil, Argentina and Uruguay. A feeding trial was conducted to evaluate the effect of feeding R. quelen larvae on either only an artificial diet or in combination with Artemia nauplii (AN) on larval performance and fatty acid composition. For 12 days, larvae were fed from first feeding (3 days after hatching, TL = 5.88 ± 0.23 mm) with artificial food only or a combination of artificial food and AN (co-feeding). At the end of the trial, total length of co-fed larvae was significantly higher than that of larvae fed solely artificial food (P < 0.001). No significant differences were found in survival rates. Co-feeding microdiet with a small amount of AN significantly affected larval fatty acid composition. Lipid and fatty acid composition of food and larvae revealed the importance of n-3 fatty acids for growth of black catfish larvae and that, as most freshwater fish, R. quelen larvae can elongate and desaturate linolenic acid to n-3 highly unsaturated fatty acids. Results suggest that R. quelen larvae can be fed from first feeding on microdiets as unique food source, although better larval performances are obtained by co-feeding with a small amount of AN.

Direct quantitation of omega-3 fatty acid intake of Canadian residents of a long-term care facility

An increased dietary intake of n-3 highly unsaturated fatty acids (HUFA; >or=20 carbons, >or=3 carbon-carbon double bonds), particularly eicosapentaenoic acid (EPA; 20:5n-3) and docosahexaenoic acid (DHA; 22:6n-3), is associated with the decreased risk and incidence of several morbidities afflicting the elderly, including cognitive decline, dementia, rheumatoid arthritis, and macular degeneration. In this study, the dietary intake and blood levels of fatty acids were directly determined in residents of a retirement home or assisted living phase of a continuum of care facility for Canadian seniors. Finger-tip-prick blood samples, 3-day food duplicates, and 3-day food records were collected. The fatty acid composition of food duplicates and blood was determined by gas chromatography. Fifteen participants (7 male, 8 female; 87.1 +/- 4.8 years of age) completed the protocol. The daily intake of EPA and DHA combined, determined directly, was 70 mg (95% CI, 41-119) or 0.036% of total energy (95% CI, 0.022-0.058). In finger-tip-prick blood, the percent of n-3 HUFA in total HUFA of whole blood, a biomarker of n-3 polyunsaturated fatty acid status, was 28.8 +/- 5.2%. Correlations between daily n-3 HUFA intake and n-3 HUFA in blood were not significant (r = 0.14; n = 15), but became significant after the removal of 2 participants who appeared to consume fish irregularly (r = 0.59; n = 13). The n-3 HUFA intake and corresponding n-3 HUFA blood levels of Canadian long-term care residents are lower than levels estimated to prevent several morbidities associated with aging.

MICROBIOLOGICAL AND NUTRITIONAL QUALITY OF SOUS VIDE OR TRADITIONALLY PROCESSED FISH: INFLUENCE OF FAT CONTENT

ABSTRACT Sous vide technology, which implies vacuum packaging, pasteurization and storage at a chill temperature, also implies a challenge to obtain a balance between an extended shelf life and microbiological safety of the product with a fresh‐like appearance and a high nutritional value. The aim of this work was to determine the effect of fat content of two fish species (salmon and trout) on survival of mesophilic, psychrotrophic, Enterobacteriaceae, Micrococaceae and anaerobes during sous vide cooking and their control during chilled storage for 3, 20 and 45 days. Proximate and fatty acid composition was also determined using a traditional cooking method. Analyses were undertaken comparatively with the same culinary technique for sous vide and traditionally cooked fish. Higher fat levels in all products resulted in fewer microbial reductions. In order to establish adequate pasteurization (temperature/time) combinations for the assurance of microbial quality and shelf life of sous vide processed fish, fat content and fatty acid composition of food should be considered.

The fatty acid composition of Octopus vulgaris paralarvae reared with live and inert food: deviation from their natural fatty acid profile

The fatty acids of the mature ovary, late eggs and wild juveniles of Octopus vulgaris were analysed to establish, in accordance with the published data on the fatty acid composition of hatchlings, a theoretical framework of the ideal fatty acid profile, i.e. the “natural” fatty acid profile, during the early life of the species. The time course variation of the fatty acid composition of paralarvae reared in cultures fed enriched Artemia nauplii on their own, or supplemented with encapsulated microdiets, was also analysed and compared. The fatty acid composition of the cultured planktonic paralarvae was chemometrically related to that of the wild benthic juveniles by means of a multivariate discriminant analysis. Irrespective of the dietary treatment, the artificial feeding produced distinct lipid and fatty acid profiles as compared to the “natural” one. The influence of the fatty acid profile of Artemia seems clearly reflected in the cultured O. vulgaris paralarvae. The effect of the fatty acid composition of food was evident in the paralarvae after 10 days of feeding and remained essentially unchanged during the experimental period up to 30 days. The total lipid of the cultured animals increased notably, as did the levels of monounsaturated fatty acids, to the detriment of polyunsaturated fatty acids (PUFA) and, particularly, docosahexaenoic acid (DHA). Poor growth and high mortality seemed to result from a nutritional imbalance in the fatty acid profile (i.e. DHA/eicosapentaenoic acid (EPA) ratio) produced by the artificial feeding, suggesting also that the microdiet was inefficiently digested and/or assimilated. Wild juveniles tend to lose lipids as they increase in weight. Possible causes are discussed.

Creation of a Database for the Calculation of Nutrient Intake Over Time

In 1987–1988, the first Dutch National Food Consumption Survey (DNFCS) was carried out; similar surveys were conducted in 1992 and 1997–1998. In each survey, food consumption data were converted into energy and nutrients using the most up-to-date version of the Dutch food composition table. To enable valid comparisons of nutrient intake over time specific food composition tables (Trend Table-1 (TT-1) for DNFCS-1 and TT-2 for DNFCS-2) were created. In these tables, for 20 nutrients, the composition of 550 selected food items was compared and reasons for differences were investigated. The food composition table used for DNFCS-3 (last update in 1997) was the reference table. To avoid artificial changes, differences as a consequence of improvements of the database were corrected in retrospect; real changes in the food composition remained intact. In TT-1 nearly 3500 modifications were made. Most of them concerned the composition of macronutrients. About 40% of the corrections arose from more and better analytical data; 6% were missing values. In both TTs many changes were related to the fatty acid composition of foods and were a consequence of changing the expression of saturated, monounsaturated and polyunsaturated fat into fatty acids. In TT-2 more than 2800 modifications were made; besides changes in the fatty acid composition, about 20% reflected improvements in the quality of data, and 16% were missing values. Changes in the different food groups and consequences of the modifications are discussed in more detail.

Variability in the Trans Fatty Acid Content of Foods within a Food Category: Implications for Estimation of Dietary Trans Fatty Acid Intakes

Objective: Currently, the published information on trans fatty acid composition of foods is incomplete and of questionable accuracy. Detailed fatty acid analysis of over 200 foods was undertaken for the purpose of determining the variability in trans fatty acid content among foods within a product category, and the significance of this variability to the estimation of trans fatty acids intakes from analysis of dietary intake data.Methods: The analysis of food fatty acids used gas-liquid chromatography with 100 m capillary columns and standardized methodologies for food sampling, fat extraction, separation and quantification of trans fatty acid isomers. For the purposes of this report, trans refers to all non-naturally occurring isomers including trans, cis-trans, geometric and positional isomers.Results: The results show that the amount of trans fatty acids varies considerably among foods within a category, reflecting differences in the fats and oils used in the manufacturing or preparation process. For example, the range of trans fatty acids in 17 brands of crackers was 23 to 51% total fatty acids, representing differences of from 1 to 13 g trans fatty acids per 100 g cracker. The large errors that may arise in estimates of the trans fatty acid intake of an individual are illustrated by analyses of the potential trans fatty acid intake in a sample diet, for each food as calculated using the minimum and maximum values for trans fatty acids within a given category. The results of these analyses show estimates of trans fatty acid intake from a low of 1.4 to 25.4 g a day for the same diet.Conclusion: This study shows that the wide variability in trans fatty acid content of different foods may result in large errors in the estimation of trans fatty acid intake of individuals and, potentially, groups.

Assessment of the arachidonic acid content in foods commonly consumed in the American diet.

Arachidonic acid (AA) is an extremely important fatty acid involved in cell regulation. When provided in the diet, it is cogently incorporated in membrane phospholipids and enhances eicosanoid biosynthesis in vivo and in vitro; however, controversy exists as to the levels of AA in food and in the diet. This study determined the amount of AA in cooked and raw portions of beef (rib eye), chicken (breast and thigh), eggs, pork (loin), turkey (breast), and tuna; it compared these results to values published in Agriculture Handbook No. 8 (HB-8). The cooked portions were prepared as described in HB-8. With the exception of chicken thigh and tuna, the levels of AA (w/w) in the selected foods analyzed were significantly higher, in general, than those values published in HB-8. The greatest differences were observed in beef (raw and cooked), turkey breast (raw and cooked), and pork (cooked) where AA levels were twice that of the values in HB-8. In contrast, the AA and n-3 fatty acid contents in tuna were almost half the HB-8 values. The present data indicate that HB-8 tends to underreport the amounts of AA in a number of foods commonly consumed in the American diet, and new initiatives should be considered to validate and update the current database for fatty acid composition of foods.

Lipid metabolism in experimental animals

Publications are scarce in the way in chich metabolic processes are affected by the ingestion of heated fats used to prepare food. Similarly studies measuring metabolic effects of the consumption on fried food are poorly known. The purpose of this presentation is to summarize information on frying fats and frying foods upon lipid metabolism in experimental animals. Food consumption is equivalent or even higher when oils or the fat content of frying foods are poorly alterated decreasing their acceptability when their alteration degree increase. After 4hr. experiment the digestibility and absorption coefficients of a single dosis of thermooxidized oils were significantly decreased in rats, however the digestive utilization of frying thermooxidized oils included in diets showed very little change in comparison with unused oils by feeding trials on rats. Feeding rats different frying fats induced a slight hypercholesterolemic effect being the magnitude of this effect related to the linoleic decrease in diet produced by frying. However HDL, the main rat-cholesterol carrier, also increased, thus the serum cholesterol/HDL-cholesterol ratio did not change. Results suggest that rats fed frying fats adapt their lipoprotein metabolism increasing the number of HDL particles. Deep fat frying deeply changed the fatty acid composition of foods, being possible to increase their n-9 or n-6 fatty acid and to decrease the saturated fatty acid contents by frying. When olive oil-and sunflower oil-fried sardines were used as the only protein and fat sources of rats-diets in order to prevent the dietary hypercholesterolemia it was provided that both fried-sardine diets showed a powerful check effect on the cholesterol raising effect induced by dietary cholesterol. The negative effect of feeding rats cholesterol plus bovine bile to induce hypercholesterolemia on some cell-damage markers such as lactate dehydrogenase, transaminases, alkaline phosphatase, was significantly check when olive oil- or sunflower oil-fired sardines were used in rats. However, gamma-glutamyltransferase increased when diets containing fried sardines from oils used several times for frying were consumed. In conclusion frying appears to be an useful tool to modify the fatty acid composition of food and the lipoprotein metabolism of consumers, however this culinary procedure has to be gently done to avoid high level of potential toxic compounds.

Mechanisms of the cardioprotective effect of a diet enriched with ω-3 polyunsaturated fatty acids

The review presents current views of metabolic conversions of class ω-3 polyunsaturated fatty acids (ω-3 PUFA) and their effects on the heart function. The role of these compounds in regulation of the membrane lipid composition is discussed. Within the organism, ω-3 PUFA incorporate more effectively into membrane phospholipids of the myocardium in comparison with other organs. In animals kept on a ω-3 PUFA-enriched diet, the intramembrane concentration of ω-6 PUFA, in the first place, of arachidonic acid, decreases. Substitution of ω-3 PUFA for arachidonic acid in the metabolic system of eicosanoid synthesis initiates the synthesis of prostaglandins and thromboxanes possessing lowered biological activity, thus minimizing the risk of clot formation in the cardiovascular system. As ω-3 PUFA are direct substrates for lipid peroxidation, any rise in ω-3 PUFA concentration sharply activates free-radical oxidation in the membranes of internal organs particularly in the liver. Original data are presented that in rats kept on ω-3 PUFA-enriched diets, the kinetic parameters of the Ca2+ transport system do not change. However, the resistance of the system to free radical oxidation increases considerably. This may increase myocardial resistance to free-radical-dependent injuries. A rise in the intramembrane ω-3 PUFA content which brings about structural rearrangements within lipids and changes the activity of membrane-bound enzymes in vitro, has no effect in vivo. This finding points to the existence of a mechanism compensating for changes in the fatty acid composition of foods. Data from literature analysis suggest that one of the most active participants in the compensatory system is α-tocopherol, a lipid peroxidation inhibitor and a structural stabilizer of biomembranes. With a rise in ω-3 PUFA concentration, α-tocopherol is released from the liver and blood flow and accumulated in the body (predominantly in myocardial membranes). Whereas potent chemical antioxidants display an ability to inhibit physiologically important free-radical reactions occurring in the organism, vitamin E is without side effects even when used at high concentrations. In case of long-term application of ω-3 PUFA-enriched diets, α-tocopherol must be added to the diet.