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This report provides an update from the U.S. Department of Agriculture - Centers for Disease Control and Prevention Sentinel Foods Surveillance Program, exploring changes in sodium and related nutrients (energy, potassium, total and saturated fat, and total sugar) in popular, sodium-contributing, commercially processed and restaurant foods with added sodium. In 2010-2013, we obtained 3432 samples nationwide and chemically analyzed 1654 composites plus label information for 125 foods, to determine baseline laboratory and label sodium concentrations, respectively. In 2014-2017, we re-sampled and chemically analyzed 43 of the Sentinel Foods (1181 samples), tested for significant changes of at least ±10% ( p < 0.05), in addition to tracking changes in labels for 108 Sentinel Foods. Our results show that the label sodium levels of a majority of the Sentinel Foods had not changed since baseline (~1/3rd of the products reported changes, with twice as many reductions as increases). Laboratory analyses of the 43 Sentinel Foods show that eight foods had significant changes ( p < 0.05); sodium content continues to be high and variable, and there was no consistent pattern of changes in related nutrients. Comparisons of changes in labels and laboratory sodium shows consistency for 60% of the products, i.e., similar changes (or no changes) in laboratory and label sodium content. The data from this monitoring program may help public health officials to develop strategies to reduce and monitor sodium trends in the food supply.

The flavonoid contents in vegetables are strongly influenced by domestic cooking. The objective of this study was to evaluate the effects of domestic cooking on the structurally complex flavonoids in broccoli. Raw broccoli was cooked by boiling, steaming and microwaving. Seven kaempferol (Km) glycosides and one quercetin (Qn) glycoside were identified and quantified in raw and cooked broccoli by HPLC-MS. Boiling resulted in significant loss of all flavonoids, while steaming and microwaving led to minor loses or even increases of the flavonoids. Apparent retention factors (AR) and true retention factors (TR) were calculated for individual flavonoids. AR ranged from 35.6% to 147.5% and TR ranged from 30.4% to 174.1%, respectively, depending on the cooking method and chemical structures of flavonoids. Two different ways to calculate total retention factors, "Retention Factor by Glycoside" and "Retention Factor by Aglycone", were also calculated. In conclusion, domestic cooking significantly altered the flavonoid contents in broccoli, with cooking method and chemical nature being key influential factors. Acylated Km tri- or tetra-glycosides appeared to be more resistant to domestic cooking.

Background: Nutrition labels are important tools for consumers and for supporting public health strategies. Recent, published comparison of label and laboratory sodium values for US foods, and differences by brand type (national or private-label) or source (store or restaurant [fast-food and sit-down]) is unavailable., Objective: The objective was to compare label and laboratory values for sodium and related nutrients (ie, total sugars, total fat, and saturated fat) in popular, sodium-contributing foods, and examine whether there are differences by brand type, and source., Design: During 2010 to 2014, the Nutrient Data Laboratory of the US Department of Agriculture collected 3,432 samples nationwide of 125 foods, combined one or more samples of the same food (henceforth referred to as composites), and chemically analyzed them. For this comparative post hoc analysis, the Nutrient Data Laboratory linked laboratory values for 1,390 composites (consisting of one or more samples of the same food) of 114 foods to corresponding label or website (restaurant) nutrient values., Main Outcome Measures: Label and laboratory values and their ratio for each composite, for each of the four nutrients (sodium, total fat, total sugars, and saturated fat)., Statistical Analyses Performed: Nutrient Data Laboratory analysis determined the ratio of laboratory to label value for each composite, and categorized them into six groups: ≥141%, 121% to 140%, 101% to 120%, 81% to 100%, 61% to 80%, and ≤60%. For sodium, the Nutrient Data Laboratory analysis determined the distribution of the ratios by food, food category, brand type, and source., Results: For sodium, 5% of the composites had ratios of laboratory to label values >120% and 14% had ratios ≤80%. Twenty-two percent of private-label brand composites had ratios ≤80%, compared with 12% of national brands. Only 3% of store composites had ratios >120% compared with 11% of restaurant composites. Ratios ≤80% were more prevalent among sit-down restaurants (37%) compared with fast-food restaurants (9%)., Conclusions: This study shows that a majority of label and laboratory values sampled agree and underdeclaration of label values is limited. However, there is some disagreement. Periodic monitoring of the nutrient content of foods through laboratory analyses establishes validity of the food labels and helps identify foods and food categories where the label and laboratory values do not compare well, and hence may need laboratory analyses to support accuracy of food composition data., (Copyright © 2019 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.)

Background: Seasonal variation of vitamin C in fresh fruits and vegetables is not reflected in food composition database average values, yet many factors influence content and retention., Results: Fresh fruits and vegetables were sampled on three occasions in each season, from the same local retail outlets, for 1 or 2 years. Vitamin C was significantly higher in winter-sampled spinach (436 mg kg -1 ) compared with spring (298 mg kg -1 ) and summer/fall (180 mg kg -1 ); in potatoes in summer/fall (156 mg kg -1 ) versus winter/spring (106 mg kg -1 ); and in oranges in winter (616 mg kg -1 ), spring (592 mg kg -1 ), and summer (506 mg kg -1 ). Ranges were dramatic among sampling occasions for broccoli, oranges, potatoes, and spinach (700-1210 mg kg -1 , 420-780 mg kg -1 , 70-280 mg kg -1 , and 90-660 mg kg -1 respectively). Mean values for apples, bananas, tomatoes, and potatoes differed from the USDA National Nutrient Database for Standard Reference (SR) average by ≥10% of the daily recommended intake (90 mg). For broccoli, oranges, and spinach, vitamin C was substantially above or below the SR range in 50-100% of the samples. For spinach, the average content did not differ from SR, but vitamin C in winter was 55% higher than SR., Conclusion: Database average values for vitamin C in fresh produce can significantly over- or underestimate the content in a specific food supply. © 2018 Society of Chemical Industry., (© 2018 Society of Chemical Industry.)

For nearly 20years, the National Food and Nutrient Analysis Program (NFNAP) has expanded and improved the quantity and quality of data in US Department of Agriculture's (USDA) food composition databases (FCDB) through the collection and analysis of nationally representative food samples. NFNAP employs statistically valid sampling plans, the Key Foods approach to identify and prioritize foods and nutrients, comprehensive quality control protocols, and analytical oversight to generate new and updated analytical data for food components. NFNAP has allowed the Nutrient Data Laboratory to keep up with the dynamic US food supply and emerging scientific research. Recently generated results for nationally representative food samples show marked changes compared to previous database values for selected nutrients. Monitoring changes in the composition of foods is critical in keeping FCDB up-to-date, so that they remain a vital tool in assessing the nutrient intake of national populations, as well as for providing dietary advice., (Published by Elsevier Ltd.)

Background: Phylloquinone is the most abundant form of vitamin K in US diets. Green vegetables are considered the predominant dietary source of phylloquinone. As our food supply diversifies and expands, the food groups that contribute to phylloquinone intake are also changing, which may change absolute intakes. Thus, it is important to identify the contributors to dietary vitamin K estimates to guide recommendations on intakes and food sources. Objective: The purpose of this study was to estimate 1 ) the amount of phylloquinone consumed in the diet of US adults, 2 ) to estimate the contribution of different food groups to phylloquinone intake in individuals with a high or low vegetable intake (≥2 or <2 cups vegetables/d), and 3 ) to characterize the contribution of different mixed dishes to phylloquinone intake. Methods: Usual phylloquinone intake was determined from NHANES 2011-2012 (≥20 y old; 2092 men and 2214 women) and the National Cancer Institute Method by utilizing a complex, stratified, multistage probability-cluster sampling design. Results: On average, 43.0% of men and 62.5% of women met the adequate intake (120 and 90 μg/d, respectively) for phylloquinone, with the lowest self-reported intakes noted among men, especially in the older age groups (51-70 and ≥71 y). Vegetables were the highest contributor to phylloquinone intake, contributing 60.0% in the high-vegetable-intake group and 36.1% in the low-vegetable-intake group. Mixed dishes were the second-highest contributor to phylloquinone intake, contributing 16.0% in the high-vegetable-intake group and 28.0% in the low-vegetable-intake group. Conclusion: Self-reported phylloquinone intakes from updated food composition data applied to NHANES 2011-2012 reveal that fewer men than women are meeting the current adequate intake. Application of current food composition data confirms that vegetables continue to be the primary dietary source of phylloquinone in the US diet. However, mixed dishes and convenience foods have emerged as previously unrecognized but important contributors to phylloquinone intake in the United States, which challenges the assumption that phylloquinone intake is a marker of a healthy diet. These findings emphasize the need for the expansion of food composition databases that consider how mixed dishes are compiled and defined., Competing Interests: Author disclosures: SGH, EGF, KJB, RLB, DBH, CHG, and SLB, no conflicts of interest., (© 2017 American Society for Nutrition.)

Background: The plant-based form of vitamin K (phylloquinone, vitamin K-1) has been well quantified in the US diet. Menaquinones (vitamin K-2) are another class of vitamin K compounds that differ from phylloquinone in the length and saturation of their side chain, but they have not been well characterized in foods. Objectives: The objectives of this study were to 1 ) quantify phylloquinone and the different forms of menaquinones [menaquinone (MK) 4-MK13] in milk, yogurt, Greek yogurt, creams, and cheeses and 2 ) compare the menaquinone contents of full-fat, reduced-fat, and nonfat dairy products. Methods: All dairy samples were either obtained from the USDA National Food and Nutrient Analysis Program or purchased from retail outlets. Phylloquinone and menaquinone concentrations in these dairy products were quantified by mass spectrometry technology. Results: Full-fat dairy products contained appreciable amounts of menaquinones, primarily in the forms of MK9, MK10, and MK11. We also measured modest amounts of phylloquinone, MK4, MK8, and MK12 in these products. In contrast, there was little MK5-7 or MK13 detected in the majority of dairy products. The total vitamin K contents of soft cheese, blue cheese, semi-soft cheese, and hard cheese were (means ± SEMs): 506 ± 63, 440 ± 41, 289 ± 38, and 282 ± 5.0 µg/100 g, respectively. Nonfermented cheeses, such as processed cheese, contained lower amounts of vitamin K (98 ± 11 µg/100 g). Reduced-fat or fat-free dairy products contained ∼5-22% of the vitamin K found in full-fat equivalents. For example, total vitamin K contents of full-fat milk (4% fat), 2%-fat milk, 1%-fat milk, and nonfat milk were 38.1 ± 8.6, 19.4 ± 7.7, 12.9 ± 2.0, and 7.7 ± 2.9 µg/100 g, respectively. Conclusions: To the best of our knowledge, this is the first report of menaquinone contents of US dairy products. Findings indicate that the amount of vitamin K contents in dairy products is high and proportional to the fat content of the product.

Vitamin K food composition data have historically been limited to plant-based phylloquinone (vitamin K1). The purpose of this study was to expand analysis of vitamin K to animal products and to measure phylloquinone and 10 forms of menaquinones (vitamin K2) in processed and fresh-cut pork products. Nationally representative samples of processed pork products (n = 28) were obtained through USDA's National Food and Nutrition Analysis Program, and fresh pork (six cuts; n = 5 per cut) and bacon (n = 4) were purchased from local retail outlets. All samples were analyzed by high-performance liquid chromatography (phylloquinone and menaquinone-4) and atmospheric-pressure chemical ionization-liquid chromatography-mass spectrometry (menaquinone-5 to menaquinone-13). Although low in phylloquinone (<2.1 ± 0.5 μg of phylloquinone per 100 g), all processed pork products and fresh pork cuts contained menaquinone-4, menaquinone-10, and menaquinone-11 (range: [35.1 ± 11.0]-[534 ± 89.0] μg of menaquinones per 100 g). The total menaquinone contents of processed pork products were correlated with fat contents (r = 0.935). In summary, processed and fresh-cut pork products are a rich dietary source of menaquinones that are currently unaccounted for in assessment of vitamin K in the food supply.

Purpose: The purpose of this study was to provide baseline estimates of sodium levels in 125 popular, sodium-contributing, commercially processed and restaurant foods in the U.S., to assess future changes as manufacturers reformulate foods., Methods: In 2010-2013, we obtained ~ 5200 sample units from up to 12 locations and analyzed 1654 composites for sodium and related nutrients (potassium, total dietary fiber, total and saturated fat, and total sugar), as part of the U.S. Department of Agriculture-led sodium-monitoring program. We determined sodium content as mg/100 g, mg/serving, and mg/kcal and compared them against U.S. Food and Drug Administration's (FDA) sodium limits for "low" and "healthy" claims and to the optimal sodium level of < 1.1 mg/kcal, extrapolating from the Healthy Eating Index-2010., Results: Results from this study represent the baseline nutrient values to use in assessing future changes as foods are reformulated for sodium reduction. Sodium levels in over half (69 of 125) of the foods, including all main dishes and most Sentinel Foods from fast-food outlets or restaurants (29 of 33 foods), exceeded the FDA sodium limit for using the claim "healthy". Only 13 of 125 foods had sodium values below 1.1 mg/kcal. We observed a wide range of sodium content among similar food types and brands., Conclusions: Current sodium levels in commercially processed and restaurant foods in the U.S. are high and variable. Targeted benchmarks and increased awareness of high sodium content and variability in foods would support reduction of sodium intakes in the U.S.

The scientific community continues to be interested in potential links between flavonoid intakes and beneficial health effects associated with certain chronic diseases such as CVD, some cancers and type 2 diabetes. Three separate flavonoid databases (Flavonoids, Isoflavones and Proanthocyanidins) developed by the USDA Agricultural Research Service since 1999 with frequent updates have been used to estimate dietary flavonoid intakes, and investigate their health effects. However, each of these databases contains only a limited number of foods. The USDA has constructed a new Expanded Flavonoids Database for approximately 2900 commonly consumed foods, using analytical values from their existing flavonoid databases (Flavonoid Release 3.1 and Isoflavone Release 2.0) as the foundation to calculate values for all the twenty-nine flavonoid compounds included in these two databases. Thus, the new database provides full flavonoid profiles for twenty-nine predominant dietary flavonoid compounds for every food in the database. Original analytical values in Flavonoid Release 3.1 and Isoflavone Release 2.0 for corresponding foods were retained in the newly constructed database. Proanthocyanidins are not included in the expanded database. The process of formulating the new database includes various calculation techniques. This article describes the process of populating values for the twenty-nine flavonoid compounds for every food in the dataset, along with challenges encountered and resolutions suggested. The new expanded flavonoid database released on the Nutrient Data Laboratory's website would provide uniformity in estimations of flavonoid content in foods and will be a valuable tool for epidemiological studies to assess dietary intakes.

Background: Most sodium in the US diet comes from commercially processed and restaurant foods. Sodium reduction in these foods is key to several recent public health efforts., Objective: The objective was to provide an overview of a program led by the USDA, in partnership with other government agencies, to monitor sodium contents in commercially processed and restaurant foods in the United States. We also present comparisons of nutrients generated under the program to older data., Design: We track ∼125 commercially processed and restaurant food items ("sentinel foods") annually using information from food manufacturers and periodically by nationwide sampling and laboratory analyses. In addition, we monitor >1100 other commercially processed and restaurant food items, termed "priority-2 foods" (P2Fs) biennially by using information from food manufacturers. These foods serve as indicators for assessing changes in the sodium content of commercially processed and restaurant foods in the United States. We sampled all sentinel foods nationwide and reviewed all P2Fs in 2010-2013 to determine baseline sodium concentrations., Results: We updated sodium values for 73 sentinel foods and 551 P2Fs in the USDA's National Nutrient Database for Standard Reference (releases 23-26). Sodium values changed by at least 10% for 43 of the sentinel foods, which, for 31 foods, including commonly consumed foods such as bread, tomato catsup, and potato chips, the newer sodium values were lower. Changes in the concentrations of related nutrients (total and saturated fat, total sugar, potassium, or dietary fiber) that were recommended by the 2010 Dietary Guidelines for Americans for reduced or increased consumption accompanied sodium reduction. The results of sodium reduction efforts, based on resampling of the sentinel foods or re-review of P2Fs, will become available beginning in 2015., Conclusion: This monitoring program tracks sodium reduction efforts, improves food composition databases, and strengthens national nutrition monitoring., (© 2015 American Society for Nutrition.)

The Mushroom Council convened the Mushrooms and Health Summit in Washington, DC, on 9-10 September 2013. The proceedings are synthesized in this article. Although mushrooms have long been regarded as health-promoting foods, research specific to their role in a healthful diet and in health promotion has advanced in the past decade. The earliest mushroom cultivation was documented in China, which remains among the top global mushroom producers, along with the United States, Italy, The Netherlands, and Poland. Although considered a vegetable in dietary advice, mushrooms are fungi, set apart by vitamin B-12 in very low quantity but in the same form found in meat, ergosterol converted with UV light to vitamin D2, and conjugated linoleic acid. Mushrooms are a rare source of ergothioneine as well as selenium, fiber, and several other vitamins and minerals. Some preclinical and clinical studies suggest impacts of mushrooms on cognition, weight management, oral health, and cancer risk. Preliminary evidence suggests that mushrooms may support healthy immune and inflammatory responses through interaction with the gut microbiota, enhancing development of adaptive immunity, and improved immune cell functionality. In addition to imparting direct nutritional and health benefits, analysis of U.S. food intake survey data reveals that mushrooms are associated with higher dietary quality. Also, early sensory research suggests that mushrooms blended with meats and lower sodium dishes are well liked and may help to reduce intakes of red meat and salt without compromising taste. As research progresses on the specific health effects of mushrooms, there is a need for effective communication efforts to leverage mushrooms to improve overall dietary quality., (© 2014 American Society for Nutrition.)

White button, crimini, shiitake, maitake, enoki, oyster, chanterelle, morel, portabella, and uv-treated portabella mushrooms were sampled from U.S. retail outlets and major producers. Folate [5-methyltetrahydrofolate (5-CH 3 -H 4 folate), 10-formyl folate (10-HCO-folate), 5-formyltetrahydrofolate (5-HCO-H 4 folate)] was analysed using a validated LC-MS method in four composites of each product, including an in-house mushroom control composite and a reference material (BCR 485 Lyophilised Mixed Vegetables). Chanterelle and morel had the lowest total folate (2-6μg/100g), oyster had the highest (mean, 44.2μg/100g); other types contained 12.4μg/100g (shiitake) to 29.8μg/100g (vitamin D-enhanced portabella). Enoki and oyster had almost exclusively 5-CH 3 -H 4 folate. Morel and chanterelle contained predominately formyl folates. Other species had similar amounts of 5-CH 3 -H 4 folate and formyl folates. Enoki, oyster, and shiitake, unlike all others, had low to non-detectable 10-HCO-folate (<1μg/100g). These precise data on the composition of folate vitamers in different types of mushrooms will facilitate assessment of the dietary contribution of naturally occurring folate., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Vitamin D(2) (ergocalciferol) and sterols were analyzed in mushrooms sampled nationwide in the United States to update the USDA Nutrient Database for Standard Reference. Vitamin D(2) was assayed using HPLC with [(3)H]-vitamin D(3) internal standard and sterols by GC-FID mass spectrometric (MS) confirmation. Vitamin D(2) was low (0.1-0.3 μg/100 g) in Agaricus bisporus (white button, crimini, portabella) and enoki, moderate in shiitake and oyster (0.4-0.7 μg/100 g), and high in morel, chanterelle, maitake (5.2-28.1 μg/100 g) and UV-treated portabella (3.4-20.9 μg/100 g), with significant variability among composites for some types. Ergosterol (mg/100 g) was highest in maitake and shiitake (79.2, 84.9) and lowest in morel and enoki (26.3, 35.5); the range was <10 mg/100 g among white button composites but 12-50 mg/100 g among samples of other types. All mushrooms contained ergosta-5,7-dienol (22,23-dihydroergosterol) (3.53-18.0 mg/100 g) and (except morel) ergosta-7-enol. Only morel contained brassicasterol (28.6 mg/100 g) and campesterol (1.23-4.54 mg/100 g) and no ergosta-7,22-dienol. MS was critical in distinguishing campesterol from ergosta-7,22-dienol.

The National Food and Nutrient Analysis Program (NFNAP) was implemented in 1997 to update and improve the quality of food composition data maintained by the United States Department of Agriculture (USDA). NFNAP was designed to sample and analyze frequently consumed foods in the U.S. food supply using statistically rigorous sampling plans, established sample handling procedures, and qualified analytical laboratories. Methods for careful handling of food samples from acquisition to analysis were developed to ensure the integrity of the samples and subsequent generation of accurate nutrient values. The infrastructure of NFNAP, under which over 1500 foods have been sampled, mandates tested sample handling protocols for a wide variety of foods. The majority of these foods were categorized into several major areas: 1) frozen foods; 2) fresh produce and/or highly perishable foods requiring refrigeration; 3) fast foods and prepared foods; 4) shelf-stable foods; 5) specialized study and non-retail (point of production) foods; and 6) foods from remote areas (e.g. American Indian reservations). This paper describes the sample handling approaches, from the collection and receipt of the food items to the preparation of the analytical samples, with emphasis on the strategies developed for those foods. It provides a foundation for developing sample handling protocols of foods to be analyzed under NFNAP and for other researchers working on similar projects.

The National Food and Nutrient Analysis Program (NFNAP) was designed to expand the quantity and improve the quality of data in the United States Department of Agriculture (USDA) food composition databases through the collection and analysis of nationally representative samples of foods and beverages. This paper describes some of the findings from the NFNAP and its impact on the food composition databases produced by USDA. The NFNAP employs statistically valid sampling plans, comprehensive quality control, and USDA analytical oversight as part of the program to generate new and updated analytical data for food components. USDA food consumption and composition data were used to target those foods that are major contributors of nutrients of public health significance to the U.S. diet (454 Key Foods). Foods were ranked using a scoring system, divided into quartiles, and reviewed to determine the impact of changes in their composition compared to historical values. Foods were purchased from several types of locations, such as retail outlets and fast food restaurants in different geographic areas as determined by the sampling plan, then composited and sent for analysis to commercial laboratories and cooperators, along with quality control materials. Comparisons were made to assess differences between new NFNAP means generated from original analytical data and historical means. Recently generated results for nationally representative food samples show marked changes compared to database values for selected nutrients from unknown or non-representative sampling. A number of changes were observed in many high consumption foods, e.g. the vitamin A value for cooked carrots decreased from 1,225 to 860 RAE/100g; the fat value for fast food French fried potatoes increased by 13% (14.08 to 17.06 g/100g). Trans fatty acids in margarine have decreased as companies reformulate their products in response to the required addition of trans fatty acids content on the nutrition label. Values decreased from 19.7 g/100 in 2002 to 14.8 g/100 in 2006 for 80%-fat stick margarines and to 4.52 g/100 g for 80%-fat tub margarines. These changes reflect improved strategies for sampling and analysis of representative food samples, which enhance the reliability of nutrient estimates for Key Foods and subsequent assessments of nutrient intake.

Folic acid (pteroylmonoglutamic acid) is used in enriched foods; however, very little folic acid occurs naturally in fruits and vegetables. For the U.S. Department of Agriculture's National Food and Nutrient Analysis Program, a number of fruits and vegetables have been assayed for endogenous folates, by a liquid chromatography-mass spectrometry method, to evaluate the accuracy of existing data for total folate determined by standard microbiological analysis. Folate in red and green sweet peppers (Capsicum annuum) differed notably (70.2 and 20.7 microg/100 g, respectively) and exceeded existing values determined by microbiological assay (18 and 11 microg/100 g, respectively). 5-Methyltetrahydrofolate was the predominant vitamer, but a significant amount of 5-formyltetrahydrolfolate and some 10-formylfolate were present. These findings may assist in making dietary recommendations or developing research diets related to folate. The data from this study have been used to update the folate values in release 19 of the USDA Nutrient Database for Standard Reference.

Analytical data are reported for 20 flavonoids (as aglycones) determined for more than 60 fresh fruits, vegetables, and nuts collected from four regions across the United States at two times of the year. Sample collection was designed and implemented by the Nutrient Data Laboratory (USDA). Analyses of eight flavan-3-ols (catechin, catechin gallate, epicatechin, epicatechin gallate, epigallocatechin, epigallocatechin gallate, gallocatechin, and gallocatechin gallate), six anthocyanins (cyanidin, delphinidin, malvidin, pelargonidin, peonidin, and petunidin), two flavanones (hesperetin and naringenin), two flavones (apigenin and luteolin), and two flavonols (myricetin and quercetin) were performed by the Food Composition Laboratory (USDA) using a hydrolysis method for the anthocyanidins, flavones, and flavonols and a direct extraction method for the flavan-3-ols and flavanones. Experimental results compare favorably (few statistically significant differences) to literature values in the flavonoid and proanthocyanidin database previously compiled by the Nutrient Data Laboratory. The results of this study showed a seasonal variation only for blueberries. This study also showed that the variation in the flavonoid content of foods, as purchased by the U.S. consumer, is very large. The relative standard deviation, averaged for each flavonoid in each food, was 168%.

In 1998, the United States introduced mandatory fortification of enriched cereal-grain products with folic acid to reduce the incidence of neural tube defects. As a consequence, substantial amounts of folic acid, the synthetic form of folate, were added to the American diet, and the ability to assess folic acid intake took on greater importance. The purpose of the current study was to separate and quantify folic acid and 5-methyltetrahydrofolate, the most prominent naturally occurring folate in fortified foods, with a reliable and robust method. Folates were heat-extracted from food samples. A trienzyme treatment (alpha-amylase, rat plasma conjugase, and protease) was applied to the extracts followed by purification by affinity chromatography. Folic acid and 5-methyltetrahydrofolate were separated and quantified by reversed-phase HPLC with fluorescence and UV detection. A gradient elution with phosphate buffer and acetonitrile was used to separate the different forms of folates. The method gave a linear response in a range of 0.1-3 mumol/L and 0.0125-0.25 mumol/L for folic acid and 5-methyltetrahydrofolate, respectively. These ranges were similar to the expected levels in the samples. The CV of the peak areas of folic acid and 5-methyltetrahydrofolate for 5 commercial wheat flour samples extracted and run separately on the same day was 2.0 and 5.7% and, run over 5 consecutive days, was 7.2 and 7.3%, respectively. Total folate values in 45 samples of fortified food measured by HPLC and by the traditional microbiological assay demonstrated a high correlation (r(2) = 0.986).

Anthocyanins (ACNs) are water-soluble plant pigments that have important functions in plant physiology as well as possible health effects. Over 100 common foods were screened for ACNs, and 24 of them were found to contain ACNs. Concentrations of total ACNs varied considerably from 0.7 to 1480 mg/100 g of fresh weight in gooseberry ('Careless' variety) and chokeberry, respectively. Not only does the concentration vary, but the specific anthocyanins present in foods are also quite different. Only six common aglycones, delphinidin, cyanidin, petunidin, pelargonidin, peonidin, and malvidin, were found in all of these foods. However, their sugar moieties and acylation patterns varied from food to food. Results from this study will add to the available data for the USDA Nutrient Database of flavonoids. On the basis of the concentration data and updated food intake data from NHANES 2001-2002, the daily intake of ACNs is estimated to be 12.5 mg/day/person in the United States. Of the different aglycones, cyanidin, delphinidin, and malvidin were estimated to contribute 45, 21, and 15%, respectively, of the total ACN intake. Nonacylated contributed 77% compared to 23% from acylated ACNs.

The US Department of Agriculture (USDA) Nutrient Data Laboratory (NDL) develops and maintains the USDA National Nutrient Databank System (NDBS). Data are released from the NDBS for scientific and public use through the USDA National Nutrient Database for Standard Reference (SR) ( http://www.ars.usda.gov/ba/bhnrc/ndl ). In 1997 the NDL initiated the National Food and Nutrient Analysis Program (NFNAP) to update and expand its food-composition data. The program included: 1) nationwide probability-based sampling of foods; 2) central processing and archiving of food samples; 3) analysis of food components at commercial, government, and university laboratories; 4) incorporation of new analytical data into the NDBS; and 5) dissemination of these data to the scientific community. A key feature and strength of the NFNAP was a rigorous quality-control program that enabled independent verification of the accuracy and precision of analytical results. Custom-made food-control composites and/or commercially available certified reference materials were sent to the laboratories, blinded, with the samples. Data for these materials were essential to ongoing monitoring of analytical work, to identify and resolve suspected analytical problems, to ensure the accuracy and precision of results for the NFNAP food samples.

The purpose of this study was to determine the contents of three forms of vitamin K [phylloquinone, dihydrophylloquinone, and menaquinone-4 (MK-4)] in representative samples (including different samples within the same food category) of meat (n = 128), dairy and eggs (n = 24), and fast foods (n = 169) common to the U.S. diet. The findings of our analysis indicate that no single food item in these categories is a rich dietary source of any one form of vitamin K. However, these foods are often consumed in large quantities; hence, they may be of importance in overall contribution to total vitamin K intake. The presence of MK-4 in meat, eggs, and dairy foods could be important as physiologic functions unique to MK-4 are identified.

Analysis of total folate concentration measured by microbiological assay in a variety of foods submitted in a routine manner to experienced laboratories that regularly perform folate analysis on fee-for-service basis was evaluated. Homogenates of fresh strawberries, frozen spinach, orange juice, frozen meat and vegetable pizza, dry macaroni, and dried pinto beans were prepared and stored under conditions previously determined to maintain stability of folate content. An aliquot of each composite and of 3 certified reference materials were sent on each of 4 occasions to 4 laboratories. Results for macaroni and pizza, the only folic acid-fortified foods, had considerably lower between-laboratory variation (CV(B)) with CV(B) of 9-11% versus >45% for other foods. Mean total folate ranged from 14 to 279 microg/100 g for a mixed vegetable reference material, from 5 to 70 microg/100 g for strawberries, and from 28 to 81 microg/100 g for wholemeal flour. Only 1 laboratory reported using a tri-enzyme extraction, and all laboratories used folic acid fortified foods as internal control materials. Users of commercial total folate analysis should understand the uncertainty in values determined by microbiological assay, particularly for foods containing primarily naturally occurring folate, which may not be apparent when replicate samples are not submitted for analysis.

Both lipophilic and hydrophilic antioxidant capacities were determined using the oxygen radical absorbance capacity (ORAC(FL)) assay with fluorescein as the fluorescent probe and 2,2'-azobis(2-amidinopropane) dihydrochloride as a peroxyl radical generator on over 100 different kinds of foods, including fruits, vegetables, nuts, dried fruits, spices, cereals, infant, and other foods. Most of the foods were collected from four different regions and during two different seasons in U.S. markets. Total phenolics of each sample were also measured using the Folin-Ciocalteu reagent. Hydrophilic ORAC(FL) values (H-ORAC(FL)) ranged from 0.87 to 2641 micromol of Trolox equivalents (TE)/g among all of the foods, whereas lipophilic ORAC(FL) values (L-ORAC(FL)) ranged from 0.07 to 1611 micromol of TE/g. Generally, L-ORAC(FL) values were <10% of the H-ORAC(FL) values except for a very few samples. Total antioxidant capacity was calculated by combining L-ORAC(FL) and H-ORAC(FL). Differences of ORAC(FL) values in fruits and vegetables from different seasons and regions were relatively large for some foods but could not be analyzed in detail because of the sampling scheme. Two different processing methods, cooking and peeling, were used on selected foods to evaluate the impact of processing on ORAC(FL). The data demonstrated that processing can have significant effects on ORAC(FL). Considering all of the foods analyzed, the relationship between TP and H-ORAC(FL) showed a very weak correlation. Total hydrophilic and lipophilic antioxidant capacity intakes were calculated to be 5558 and 166 micromol of TE/day, respectively, on the basis of data from the USDA Continuing Survey of Food Intakes by Individuals (1994-1996).

Assessment of vitamin K dietary intakes has been limited by incomplete vitamin K food composition data for the US food supply. The phylloquinone (vitamin K(1)) concentrations of nuts (n=76) and fruits (n=215) were determined by high-performance liquid chromatography. Each sample represented a composite of units obtained from 12 to 24 outlets, which provided geographic representation of the US food supply. With the exception of pine nuts and cashews, which contain 53.9 and 34.8 microg of phylloquinone per 100 g of nut, respectively, nuts are not important dietary sources of vitamin K. Similarly, most fruits are not important sources of vitamin K, with the exception of some berries, green fruits, and prunes. Menu planning for patients on warfarin can include a healthy diet including fruits and nuts without compromising the stability of their oral anticoagulation therapy.

The United States Department of Agriculture's Nutrient Data Bank contains a wealth of information on the composition of foods. These data are made available to the public through Agriculture Handbook No. 8, Composition of Foods: Raw, Processed, Prepared, its computerized form-the USDA Nutrient Data Base for Standard Reference, and other publications. Food components in Agriculture Handbook No. 8 include proximate components, minerals, vitamins, fatty acids, cholesterol, phytosterols, and amino acids. Other tables and data sets containing food components of special interest such as vitamins D and K, selenium, and sugars, are also available. This paper describes how to obtain the data in either printed or electronic form. Information on obtaining the data through the Nutrient Data Bank Bulletin Board or the Internet is also presented.

Data from the 1985 Continuing Survey of Food Intakes by individuals were used to calculate the contributions of individual foods to women's intakes of energy, protein, carbohydrate, fat, saturated fatty acids, cholesterol, and fiber. We separated nearly all food mixtures into their constituent ingredients, grouped the ingredients together with similar foods, and examined the contributions of those foods. Yeast breads that were neither whole grain nor higher fiber contributed about 7% of the energy to the diets, which made them the leading source of energy of the foods we examined. The leading sources of protein were animal products: poultry contributed approximately 12%, beef contributed about 19%, cheese contributed about 8%, and pork contributed about 6%. The various fats and oils were the greatest contributors to fat, and cheese was the chief source of saturated fatty acids. Eggs were the major source of cholesterol; they provided around 36% of the total. Two of the top three sources of carbohydrate--regular soft drinks and sugar--are composed entirely of simple sugars. Potatoes provided around 11% of the fiber, which made them the leading source of fiber. This article shows that the relative ranking of foods and the contribution of each food depend on the way food codes are combined. Therefore, citing one food as the major source of a particular food component without including documentation of how foods are combined can be misleading.

This study examined the effect of using two different methods for categorizing food mixtures when calculating the contribution of various food groups to energy, macronutrient, cholesterol, and fiber intakes. Using method 1, each food mixture was classified as a single item and assigned to a food group according to its main ingredient. Using method 2, most of the food mixtures were separated into their constituent ingredients, and each ingredient was assigned to its appropriate food group. Data were from 1,032 women who provided at least 4 days of dietary data in the U.S. Department of Agriculture's 1985 Continuing Survey of Food Intakes by Individuals. We found that the importance of each food group's contribution to individual dietary components varied depending on the method used to categorize the food mixtures. When food mixtures were separated into their constituent ingredients before assigning foods to food groups, the contributions of meat, fish, poultry, and grain products declined for each of the seven dietary components studied. At the same time, the contributions of milk products, fats, and oils increased for most of the seven components. The results highlight the importance of foods eaten as part of food mixtures to the intake of energy, macronutrients, cholesterol, and fiber.

The U.S. Department of Agriculture's (USDA) Nutrient Data Base for Nationwide Dietary Intake Surveys is specifically organized and maintained to analyze data from nationwide dietary surveys within the federal government's National Nutrition Monitoring System. These surveys include the Nationwide Food Consumption Survey and the Continuing Survey of Food Intakes by Individuals conducted by USDA, and the National Health and Nutrition Examination Survey conducted by the Department of Health and Human Services (DHHS). Each public release of the data base covers one or more specific surveys. The data base contains data for energy and 28 components for over 5000 food items. Data are based on the latest information from USDAs National Nutrient Data Bank, the computer-based system used to update USDAs standard reference on food composition, Agriculture Handbook No. 8. An automated system is also used to update the survey nutrient data base with new information released from the Nutrient Data Bank. This system includes three supplementary data sets (primary nutrient data set, recipe file, and table of nutrient retention factors) and a computer program for calculating nutrient content of mixed food items based on nutrient content of their ingredients. Updates are performed at the beginning of new surveys to incorporate the most up-to-date nutrient values.