Journal of Food Composition and Analysis

Published by Elsevier
Online ISSN: 1096-0481
Publications
Article
The National Cancer Institute (NCI) is developing an automated, self-administered 24-hour dietary recall (ASA24) application to collect and code dietary intake data. The goal of the ASA24 development is to create a web-based dietary interview based on the US Department of Agriculture (USDA) Automated Multiple Pass Method (AMPM) instrument currently used in the National Health and Nutrition Examination Survey (NHANES). The ASA24 food list, detail probes, and portion probes were drawn from the AMPM instrument; portion-size pictures from Baylor College of Medicine's Food Intake Recording Software System (FIRSSt) were added; and the food code/portion code assignments were linked to the USDA Food and Nutrient Database for Dietary Studies (FNDDS). The requirements that the interview be self-administered and fully auto-coded presented several challenges as the AMPM probes and responses were linked with the FNDDS food codes and portion pictures. This linking was accomplished through a "food pathway," or the sequence of steps that leads from a respondent's initial food selection, through the AMPM probes and portion pictures, to the point at which a food code and gram weight portion size are assigned. The ASA24 interview database that accomplishes this contains more than 1,100 food probes and more than 2 million food pathways and will include about 10,000 pictures of individual foods depicting up to 8 portion sizes per food. The ASA24 will make the administration of multiple days of recalls in large-scale studies economical and feasible.
 
Article
The Nutrient Data Laboratory of the United States Department of Agriculture (USDA) is collaborating with the Office of Dietary Supplements (ODS), the National Center for Health Statistics (NCHS), and other government agencies to design and populate a dietary supplement ingredient database (DSID). This analytically based, publicly available database will provide reliable estimates of vitamin and mineral content of dietary supplement (DS) products. The DSID will initially be populated with multivitamin/mineral (MVM) products because they are the most commonly consumed supplements. Challenges associated with the analysis of MVMs were identified and investigated. A pilot study addressing the identification of appropriate analytical methods, sample preparation protocols, and experienced laboratories for the analysis of 12 vitamins and 11 minerals in adult MVM supplement products was completed. Preliminary studies support the development of additional analytical studies with results that can be applied to the DSID. Total intakes from foods and supplements are needed to evaluate the associations between dietary components and health. The DSID will provide better estimates of actual nutrient intake from supplements than databases that rely on label values alone.
 
Article
Major sources of flavonoids were identified, and mean intakes over several decades were reported, among 1638 participants (mean age 62.1 +/- 16.0 y), of the Baltimore Longitudinal Study of Aging (BLSA). Dietary data were collected using 7-day diet records during three time periods (1980s, 1990s and 2000-present), and the USDA flavonoid, proanthocyanidin and isoflavone databases were used to estimate dietary flavonoid intakes. Dietary intake data were divided according to decade of visit. Foods were matched with appropriate foods in the USDA databases. Mixed dishes were disaggregated to individual foods and a similar procedure was followed. Total flavonoids and five sub-classes of flavonoids, including flavonols, flavones, flavanones, flavan-3-ols and anthocyanidins, were computed by summing appropriate compounds. The median intakes of flavonoids and the contributions of various foods to intakes were calculated by decade. Age and sex adjusted mean (SE) daily intakes of flavonoids increased from 250 (7.4) in the 1980s to 280 (9.9) mg in the 2000s. Top contributors of flavonoids were tea, apple/pear (and juices), citrus fruits (and juices), peaches, plums, grapes, nectarines (and juices) and chocolate. The data show an increase in the consumption of flavonoids over the three decades, which appears to be related to intake of fruit.
 
Article
Our objective was to identify major dietary sources of whole grains and to describe the construction of a database of whole grain content of foods. Dietary information was collected with 7-d food records from men and women in the Baltimore Longitudinal Study of Aging, mean age 62.1 +/- 16.0 years, who participated in the dietary assessment portion of the study (n = 1516), and estimates of whole grain intake were obtained from a newly developed database. The Pyramid Servings database and 1994-1996 Continuing Survey of Food Intakes by Individuals (CSFII) recipe ingredients database were then used to calculate both servings and gram weights of whole grain intakes. Mean intakes of whole grains, refined grains, and total grains, as well as frequency of intake for major whole grain food groups and whole grain content for each group, were calculated. Top contributors of whole grains were ready-to-eat breakfast cereals (made with whole grain as well as bran), hot breakfast cereals (made with whole grain), multi-grain bread, and whole wheat bread. While more research is needed to better understand the benefits of whole grains, the development of research tools, including databases to accurately assess whole grain intake, is a critical step in completing such research.
 
Article
An easily administered food frequency questionnaire (FFQ)/dietary screener was developed for current (adult) and retrospective (adolescent) intakes of nutrients important for bone development and maintenance. This tool quantified serving sizes and nutrients from foods using gender and age specific techniques. Nutrients of interest were calcium, vitamin D, caffeine and alcohol, and 15 categories of foods were selected for inclusion based on frequency of intake and nutrient density. Calcium-contributing foods were selected from published dietary intake assessment tools. Foods contributing vitamin D, caffeine and alcohol were selected based on nutrient density and Midwest consumption practices. Serving sizes were quantified in standard serving units or as small, medium and large servings. Food items selected for the FFQ/dietary screener were matched to foods from the United States Department of Agriculture (USDA) Continuing Survey of Food Intakes by Individuals (CSFII). Calcium, caffeine and alcohol values were assigned using CSFII data files at median values per 100g intake. CSFII midpoint tertile frequency of intake values for males and females 14-18 and 25-45 years old were used to establish serving weights for small, medium and large servings. CSFII data files provide an efficient way for estimating typical intakes, serving sizes and nutrient values for target groups. Age- and gender-derived data provided realistic estimates of nutrient intakes when using FFQ/dietary screener assessment method.
 
Article
Heterocyclic amine (HCA) concentrations were measured in meat and fish samples cooked by pan-frying, grilling and churrasco (Brazilian barbecue) to various levels of doneness in accordance with the cooking methods most commonly used in Brazil. HCAs were extracted by the Blue-rayon absorption method and measured by liquid chromatography-mass spectrometry. 2-Amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx), and 2-amino-3,4,8-trimethylimidazo[4,5-f]quinoxaline (4,8-DiMeIQx) were sharply increased in very well-done meats and fish. HCA levels varied somewhat across cooking methods: levels of PhIP (ng/g) in very well-done, non-marinated samples were particularly high for churrasco (31.8 in the exterior of the sample), compared to lower levels for grilled (16.3), and pan-fried beef (0.58). On comparison across foods, chicken contained higher HCA levels than other non-marinated samples. For example, PhIP levels (ng/g) in very well-done pan-fried foods were 34.6 for chicken with the skin, 0.58 for beef, 7.25 for pork, 2.28 for sardines, and 7.37 for salmon cooked with the skin. HCA levels were lower in marinated meats and fish than in non-marinated samples, except for pan-fried salmon. This study provides valuable information which will allow the estimation of dietary HCA exposure using an epidemiologic questionnaire and the investigation of the association of HCA intake with cancer risk in Brazil.
 
Article
Dietary N-nitroso compounds are carcinogens synthesized during food processing from two main classes of precursors, oxides of nitrogen and amines or amides. Quantification of the dietary intake of N-nitroso compounds is significant to human cancers, including those of the stomach and upper gastro-intestinal tract, colon, and brain. Previous studies investigating these cancers primarily used proxy estimates of N-nitroso intake and not a full and complete database. In this report, we describe the development of a database to be used in conjunction with a food frequency questionnaire (FFQ) or twenty-four hour dietary records. Published analytical data for N-nitroso compounds were compiled and evaluated for inclusion in the database. The final database consisted of 23 different N-nitroso compounds for 500 foods from 39 different food subgroups. Next, database foods were matched to foods in a standard FFQ by imputation, or calculated value, or assumed zero. Using the FFQ modified with N-nitroso values, we evaluated the ability to compute N-nitroso intakes for a sample of healthy control subjects of cancer epidemiological studies. N-nitroso content of food items ranged from <0.01μg/100 g. to 142 μg/100 g and the richest sources were sausage, smoked meats, bacon, and luncheon meats. The database is useful to quantify N-nitroso intake for observational and epidemiological studies.
 
Article
In response to the need to assess both food and supplemental sources of nutrients, we have expanded the capabilities of Nutrition Data System for Research (NDSR) software to allow for assessing dietary supplement use. A Dietary Supplement Assessment Module allows for the automated collection and coding of dietary supplement use. The module is designed for use in conjunction with the software's 24-hour dietary recall features. The medication inventory method, commonly used in pharmaceutical research, served as the basis for the module's assessment approach. In adapting this approach for use in our software we designed a tiered structure that involves first screening for use of dietary supplements, then collecting product detail (e.g. full name of product, number of times taken, etc.), and finally reviewing the information with the participant. Preliminary results from a demonstration study being conducted to evaluate the Module indicate the assessment approach is acceptable to both participants and interviewers. Collecting dietary supplement use information significantly increases interview time, especially for those using multiple products. A validation study is needed to determine whether the new method results in accurate estimation of nutrient intake from supplemental sources.
 
Article
The software available with some food composition databases allows for the dietary assessment of individuals and groups and may provide graphic comparisons of nutrient intakes to dietary standards. Four factors to consider when choosing a computerized dietary assessment system are availability of desired database features, efficiency of the search engine in finding foods in the database, educational value of the output, and cost of purchasing and updating the software. Printed output should clearly characterize dietary adequacy with graphs or simple tables. Dietary assessment data used for research must also be available in electronic spreadsheet format for statistical analysis. Peer-reviewed papers in journals that provide overviews of the features of various computerized dietary assessment software are helpful for informing the selection process.
 
Article
Polyphenolic compounds of the flavanoid family are abundantly present in cacao seed and its cocoa products. Results from studies using cocoa products indicate beneficial effects of flavanols on cardiovascular endpoints. Evidence indicates that (-)-epicatechin is the main cacao flavanol associated with cardiovascular effects, so the accurate quantification of its content in cacao seeds or cocoa products is important. Common methods for the quantification of phenolic content in cocoa products are based on the reaction of phenols with colorimetric reagents such as the Folin-Ciocalteu (FC) In this study, we compared the FC method of phenolic determinations using 2 different standards (gallic acid and (-)-epicatechin) to construct calibration curves. We compare these results with those obtained from a simple fluorometric method (Ex(280)/Em(320) nm) used to determine catechin/(-)-epicatechin content in samples of cacao seeds and cocoa products. Values obtained from the FC method determination of polyphenols yield an overestimation of phenol (flavonoid) content when gallic acid is used as standard. Moreover, the epicatechin is a more reliable standard because of its abundance in cacao seeds and cocoa products. The use of fluorometric spectra yields a simple and highly quantitative means for a more precise and rapid quantification of cacao catechins. Fluorometric values are essentially in agreement with those reported using more cumbersome methods. In conclusion, the use of fluorescence emission spectra is a quick, practical and suitable means to quantifying catechins in cacao seeds and cocoa products.
 
Article
In the early 1960s, trivalent chromium Cr(3+) became recognized as an essential trace element due to its potential metabolic and cardiovascular benefits. No comprehensive chromium database currently exists; thus a thorough review of the literature was conducted to examine the availability and reliability of chromium data for foods. A number of key issues were identified that challenge the feasibility of adding chromium to a food and nutrient database. Foremost, dietary chromium data reported in the literature prior to 1980 cannot be relied on because of problematic analytical issues before that time. Next, paucity of data emerged as an issue that could impede database completeness. Finally, large variation in reported chromium content of foods may render disputable representative chromium values. This variation has been speculated to originate from differences in growing and particularly processing foods. Furthermore, contamination of chromium from laboratory equipment and/or materials is possible and also believed to contribute to the variation observed in reported values. As a result, database developers must carefully consider the availability and reliability of information on the chromium composition of foods when deciding whether to incorporate chromium into or exclude it from a nutrient database.
 
Article
The Environmental Determinants of Diabetes in the Young Study (TEDDY) aims at examining the associations between islet autoimmunity and various environmental exposures, (e.g. diet) in Finland, Germany, Sweden and the United States (US). In order to produce comparable results from dietary assessments, the national food composition databases (FCDB) must contain mutually comparable food composition data. Systematic comparison (definition, unit of measurement, and method of analysis) of energy, protein, fats, carbohydrates, cholesterol, fiber, 13 vitamins, and 8 minerals was carried out among the FCDB of the four countries. Total fat, cholesterol, vitamin A: retinol equivalents and beta-carotene, thiamin, riboflavin, pyridoxine, vitamin B(12), calcium, phosphorus, potassium, magnesium, iron, and zinc are comparable across all four databases. Carbohydrates, fiber, sugars, fatty acids, vitamin D, vitamin E: alpha-tocopherol, vitamin K, vitamin C, pantothenic acid, niacin, manganese, and copper are comparable or can be converted comparable at least across three of the databases. Vitamin E: alpha-tocopherol equivalents, will be comparable across all databases after Finland and Germany subtract tocotrienols from their values. Nitrogen values were added to the Swedish and US databases. After recalculation of protein from nitrogen (Sweden and US), and subtraction of fiber from the total carbohydrate (Finland) followed by recalculations of energy, these values will be comparable across the countries. Starch and folate are not comparable.
 
Article
The Supplement Reporting (SURE) study is one of the first to systematically examine the accuracy of collection of dietary supplement use data for population-based studies of diet. In 2005-2007, the SURE study collected data from 444 participants in Hawaii and Los Angeles. Several methods of collecting data were compared, including an inventory of supplements, a recall, a daily diary, and a one-page supplement frequency questionnaire. Considerable effort was put into developing an extensive supplement composition database. To quantify intakes, we extended the existing supplement composition table (SCT) used at the Cancer Research Center of Hawaii. The original SCT contained default codes for multivitamin/multimineral products to be used when insufficient detail was available to assign an existing code. However, the default concept needed to be expanded for the SURE study to include additional multivitamin/multimineral default codes, as well as single nutrients and other components. Approximately 1800 new codes were created, including 211 new default codes. Roughly 130 nutrients and 870 other components were included in the SCT at the conclusion of the study. To accurately quantify intakes from supplements, it is crucial to maintain a comprehensive supplement composition database. Future improvements to our SCT include incorporation of analytic values from the US Department of Agriculture to replace composition data taken from supplement labels.
 
Article
The development of a mobile telephone food record (mpFR) in which image analysis and volume estimation data can be indexed with the Food and Nutrient Database for Dietary Studies (FNDDS) has the potential to improve the accuracy of dietary assessment. To validate the mpFR for use with adolescents, a convenience sample of adolescents, aged 11-18 years, was recruited to eat all meals and snacks in a controlled feeding environment over a 24-hour period. Each food item matched a food code in the FNDDS 3.0. The objective of this analysis was to compare the measured energy and protein content of foods to the published values in the FNDDS. Duplicate plates of all meals and snacks were prepared, and samples of 20 foods were individually weighed, homogenized, freeze dried, and analyzed for energy with a bomb calorimeter and for protein with a Dumas nitrogen analyzer. Eleven of the twenty food items had energy values in the FNDDS within ±10% of the measured energy value. The measured energy and protein values from all foods correlated significantly with the energy (r=0.981, P<0.01) and protein (r= 0.911, P<0.01) values in the FNDDS. These results support the use of the FNDDS with the mpFR.
 
Article
Food composition databases are critical to assess and plan dietary intakes. Dietary supplement databases are also needed because dietary supplements make significant contributions to total nutrient intakes. However, no uniform system exists for classifying dietary supplement products and indexing their ingredients in such databases. Differing approaches to classifying these products make it difficult to retrieve or link information effectively. A consistent approach to classifying information within food composition databases led to the development of LanguaL™, a structured vocabulary. LanguaL™ is being adapted as an interface tool for classifying and retrieving product information in dietary supplement databases. This paper outlines proposed changes to the LanguaL™ thesaurus for indexing dietary supplement products and ingredients in databases. The choice of 12 of the original 14 LanguaL™ facets pertinent to dietary supplements, modifications to their scopes, and applications are described. The 12 chosen facets are: Product Type; Source; Part of Source; Physical State, Shape or Form; Ingredients; Preservation Method, Packing Medium, Container or Wrapping; Contact Surface; Consumer Group/Dietary Use/Label Claim; Geographic Places and Regions; and Adjunct Characteristics of food.
 
Article
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.
 
Article
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.
 
Article
To evaluate seasonal variations in antioxidant components of greenhouse cherry tomatoes, the compositional profile of fruits (“Pomodoro di Pachino”, cv. Naomi F1) harvested at six different times of the year was compared. Among tomato antioxidants, phenolic compounds (naringenin content ranged from 1.84 to 9.04 mg/100 g, rutin from 1.79 to 6.61 mg/100 g) and α-tocopherol (40–1160 μg/100 g) showed the greatest variability. Ascorbic acid (31–71 mg/100 g), carotenoids (8350–15119 μg/100 g), phenolics and α-tocopherol concentration did not show definite seasonal trends, nor correlation with solar radiation or average temperature. Nevertheless, tomatoes harvested in mid-summer were characterized by lowered lycopene levels. Greenhouse growing conditions induced the accumulation of relatively high level of antioxidants for most of the year: one serving of raw tomatoes (100 g) could provide from 50% to 120% of the recommended daily intake of vitamin C, from 13% to 27% of that of vitamin A, from 0.4% to 12% of that of vitamin E, and from 15% to 35% of the flavonoid daily intake estimated for an Italian diet.
 
Article
A new and rapid method was developed for simultaneous identification and determination of 11 polyphenols in Herba lycopi, i.e. rosmarinic acid, protocatechuic aldehyde, protocatechuic acid, caffeic acid, ferulic acid, apigenin, luteolin, quercetin, isorhamnetin, chlorogenic acid and rutin, using high performance liquid chromatography (HPLC) coupled with triple quadrupole mass spectrometry (MS/MS). Quantitation was based on multiple reactions monitoring (MRM) using the precursor → production combination for the determination of 11 analytes. The analysis was performed on an Eclipse Plus C18 column (I.D. 4.6 mm × 100 mm, 3.5 μm particle size). An electrospray ionization (ESI)-tandem interface in the negative mode was employed prior to mass spectrometric detection. With the optimized conditions, the 11 biomarkers were detected properly within 3 min. Limits of detection (LOD) ranged from 0.6 to 2.6 ng/ml. The average recoveries ranged from 95.42 to 101.11% with RSDs ≤ 2.23%. The applicability of this analytical approach was confirmed by the successful analysis of 3 samples. The established method was validated and found to be sensitive and reliable for the determination of 11 analytes in Herba lycopi.
 
Article
Eleven different species of freshwater fish caught from the Evros river (Greece) were tested by atom-absorption spectroscopy for 20 naturally occurring elements and for their proximate composition. Protein content of edible portion averaged between 18 and 23% (wet basis), fat between 0.6 and 7.3%, ash between 0.9 and 1.5%, while moisture content was between 70 and 80%. Mean element levels in the flesh of fish were:P 240 ± 38, K 400 ± 130, Na 19 ± 2.2, Li 1 ± 0.2, Ca 57 ± 8.0, Mg 57 ± 9.2, Zn 0.7 ± 0.17, and Fe 0.7 ± 0.22 mg/100 g. Sr content was below the level of detection. Mean Al, Co, Cr, Cu, Mn, Mo, and Ni concentrations were 140 ± 38, 40 ± 13, 50 ± 26, 90 ± 24, 70 ± 18, 40 ± 13, 30 ± 12 μg/ 100 g, respectively. Cd, Hg, and Pb levels averaged 0.7 ± 0.33, 10 ± 2.2, and 10 ± 1.1 μg/100 g, respectively, and none exceeded legal or suggested limits. Tin content was below the level of detection. It can be concluded that the levels of metals in the flesh of fish assayed meet food products regulations.
 
Article
The total polyphenol contents (TPC) of leaf extracts from 116 varieties of sweet potato cultivated in China were determined by Folin-Ciocalteu method. In addition, the crude extract (CE) of Pushu 53 leaves, with relatively higher TPC and its fractions of chloroform, ethyl acetate, n-butanol and water, were prepared and subjected to the determination of TPC, evaluation of antioxidant activities in vitro by assays of DPPH, ABTS and FRAP, and analysis of phenolic constituents by high performance liquid chromatography (HPLC) and HPLC–mass spectrometry. Our results show that the extracts demonstrated potential antioxidant activity, and that a satisfactory correlation between TPC and antioxidant activity was observed. In addition, the main bioactive compounds for the antioxidant activity of the extract were polyphenols, especially derivatives of caffeoylquinic acid (CQA), such as 5-CQA, 3,4-diCQA, 3,5-diCQA, and 4,5-diCQA. Their contents (8.95%) were 0.41, 3.41, 4.09, and 1.04%, respectively, accounting for 79.6% of TPC in CE (11.24%).
 
Article
Pattern recognition methods were successfully used to classify authentic apple juice by variety and geographic origin on the basis of its sugar composition. The technique was also used to discriminate 10 potential adulterants from authentic apple juice, but it had only limited success in detecting adulteration of apple juice with the adulterants at the 40% level by volume. Analysis of the nonvolatile acid profile by more traditional methods enabled the detection of some but not all adulterants. The t,-malic test could detect adulteration at the 20% but not the 10% level. Similarly, adulteration with high fructose corn syrup and pineapple juice could be detected by isotopic carbon analysis at the 20% but not the 10% level.
 
Article
The tocopherol and tocotrienol (i.e. tocol) and plant sterol contents of 14 vegetable and 9 industrial fats and oils available on the Finnish market in 2005 were determined using NP-HPLC with fluorescence detection (tocols) and GC-FID (plant sterols). Best sources of α-tocopherol were wheat germ (192 mg/100 g) and sunflower oil (59 mg/100 g). Oils richest in γ-tocopherol were camelina (72 mg/100 g), linseed (52 mg/100 g) and organic rapeseed oil (51 mg/100 g). Total tocol contents were between 4.2 mg/100 g (coconut fat) and 268 mg/100 g (wheat germ oil). Plant sterol contents ranged from 69 mg/100 g in a frying fat to 4240 mg/100 g in wheat germ oil. Organic rapeseed oil, the second best source of plant sterols, contained 887 mg/100 g. The variations of the total tocol and sterol contents in 10 rapeseed oil sub-samples analysed separately were 9.7% for tocols and 9.9% for sterols in refined rapeseed oil, and 6.3% for tocols and 4.2% for sterols, respectively, in cold-pressed rapeseed oil. In addition to the target compounds, plastochromanol-8 could be determined in all plant-based samples with contents ranging from 0.13 (walnut oil) to 18 mg/100 g (linseed oil). The lignans sesamin and sesamolin could be identified in sesame oil.
 
Article
Butterhead lettuce, rucola, watercress, kale, chicory, cabbage, Chinese cabbage, and a spinach substitute (Tetragonia expansa) are widely consumed in Southern Brazil. Samples were collected five times during a year in food markets and analyzed for total potassium, sodium, calcium, magnesium, iron, manganese, copper, and zinc by flame atomic absorption spectrometry and for moisture content. All vegetables can contribute to diet in terms of potassium, calcium and magnesium. Kale offers the highest amounts of calcium (283±43 mg Ca/100 g) and Chinese cabbage, cabbage, and butterhead lettuce the lowest, with values from 33 to 58 mg Ca/100 g. The highest concentrations of magnesium were found in kale and in the spinach substitute and they were 52±4 and 55±16 mg Ca/100 g, respectively. Moisture content varied less among samples of the same vegetable than minerals did. Four of the vegetables (kale, chicory, Chinese cabbage, and cabbage) were cooked briefly during 3 min and analyzed for the same elements. The brief cooking did not cause appreciable losses for any of the minerals.
 
Article
The reaction between (+)-catechin and glyoxylic acid was investigated as a model system of color changes usually observed during conservation and ageing of fruit-derived foods. The reaction was monitored by LC/DAD and LC/ESI-MS analysis and the formation of various phenolic compounds initially absent in the mixture was observed.Among the detected compounds, colorless bridged derivatives which were converted later to more polymerized compounds were observed. Another type of compounds exhibiting absorption maxima near 300 nm and presenting a shoulder around 350 nm were also detected. The role of all these compounds in the formation of xanthylium salts with absorption maxima ranging from 440 to 460 nm was demonstrated. Thus, xanthylium salts with various structures were shown to be formed in the studied model solution. Other compounds with strong absorption around 560 nm were also detected.This indicated the role of these compounds and the studied model solution in the color change observed during storage and especially the browning phenomenon observed in the case of grape-derived foods. Moreover, some compounds were detected through LC/ESI-MS analysis in grape-derived beverage indicating the probable occurrence of such interaction in fruit-derived foods and the implication of phenolic reactions in the organoleptic properties of fruit-derived foods.
 
Article
This study deals with the implementation and the maintenance of the ISO/IEC 17025 quality assurance system in the General Chemical State Laboratory (GCSL) of Greece. The reliability of the test results, as well as the technical competence of such a laboratory renders its accreditation, according to an international quality standard, a necessity of major importance. In the case presented here, the implemented quality assurance system includes senior management commitment, adequate employees train-ing, organizational restructure, systematic and extensive documentation, frequent internal audits and reviews, contract management and complete method validation. The laboratory's test methods, which received accreditation, refer to food product analyses i.e., oils and fats, alcohol and alcoholic spirits, food preservatives, meat and meat products, cereal and cereal products. It is clearly manifested that despite the drawbacks of developing and maintaining an efficient quality assurance system, such as the time-consuming efforts, the increased expenses and the bureaucracy, the whole process can be quite rewarding and fruitful. Improved competitiveness and reliability, increased quality awareness, greater efficiency and teamwork are the key benefits stemming from the application of the ISO/IEC 17025 standard.
 
Article
The partial compositional characteristics were determined for apple juice from 175 non-commercial varieties of apples developed from scion wood collected from approximately 12 countries and several USA geographical areas. Juices from many of the varieties were high in malic acid and potassium. Mean values for many of the attributes did not match existing compositional database value means. However, some of the overall minimum and maximum values for the various attributes (i.e., Brix°, pH, ash, TA, sucrose, glucose, fructose, sorbitol, malic, citric, fumaric, sodium, and calcium) in this study compared reasonably well with existing compositional database values. Distribution of phenolics between the various varieties was highly variable with some juices containing little if any phenolic compounds. Chlorogenic acid and phloridzin were detected in all varietal samples while arbutin and HMF were not measurable. The data developed should be useful with other databases in describing authentic apple juice and in the development of future apple commercial varieties to target specific consumer requirements.
 
Article
The main objective of this study was to introduce the artificial neural network (ANN) technique into the field of food analysis. The specific purpose was to evaluate the lipid distribution of Bt-176 transgenic maize compared to that of conventional maize. The crude oil extracted from the grains of genetically modified maize (Bt-176) and nontransgenic maize was characterized in terms of the fatty acid, sterol, tocopherol distribution as well as the lipid classes and unsaponifiable level. The content of total lipids was within the range of 3.21–3.40% of grain dry matter. Fractionation of lipids into polar and nonpolar classes showed that the transgenic maize (Bt-176) contained more polar lipids than the control maize. In general, results obtained from lipid distribution analysis showed that, except for a few minor differences, the grains of Bt-176 maize were comparable in composition to that of the control maize. On the other hand, the analytical data have been elaborated by supervised pattern recognition technique (ANN) in order to classify genetically modified maize (Bt-176) and conventional maize as well as to authenticate the origin of the samples.
 
Article
Analysis of cyanogenic potential, linamarin, acetone cyanohydrin and free HCN/CN−of 179 cultivars of cassava root grown in Oxisol Soil at Muara Experimentation, West Java, Indonesia, was conducted using picrate paper kits introduced by Bradbury et al. (1999). Two plants of each clone were harvested. Two roots were taken from each plant, peeled and cut according to protocol A of the picrate paper kits. Although the average content of cyanogenic potential of 179 cassava cultivars is 82 ppm, only 6.8% cyanogenic potentials was in the form of HCN/CN−(5.6 ppm), 23% as acetone cyanohydrin (19.9 ppm), and most of them (70%) as linamarin (57.1 ppm). The cyanogenic potential content clustered into very high levels (234–138 ppm) found in 10% of 179 cultivars, high (134–84 ppm) in 15% cultivars, medium (81–55 ppm) in 17% cultivars, low (54–36 ppm) in 19% cultivars, and very low (35–9 ppm) in 40% cultivars. The linamarin, acetone cyanohydrin and HCN/CN−were also clustered into 5 levels. The range, member of each cluster and name of the clone are given in the text. It was also found that no correlation existed between the cyanogen contents and total amount and weight of roots per plant.
 
Article
The Chinese Food Composition Tables, representing four decades of effort by the Institute of Nutrition and Food Hygiene, Chinese Academy of Preventive Medicine, Beijing, are presented in annotated translation with extensive supplementary material. Nutrient data for more than 600 foods include edible portion; proximate composition; energy, major mineral, trace element, vitamin, and cholesterol content; and amino acid and fatty acid profile. Categories of foods represented include cereals; legumes; roots, tubers, and stems; cultivated and wild vegetables; melons, squashes, and gourds; fungi and algae; fruits; nuts; meats, poultry, and eggs; dairy foods; fishes; mollusks, crustaceans, and other invertebrates; reptiles and amphibians; alcoholic and nonalcoholic beverages; condiments; confections; and infant foods. Foods are identified by English common name and Latin scientific name, and are further described by habitat (for water-dwelling creatures), cooking and preparation method, location of sample collection or analysis, and other characteristics. Original Chinese descriptions of foods are presented in Pinyin transliteration. Textual material and footnotes from the original Chinese document are translated in full. Linking codes are provided for readers having access to the original Chinese version.The supplementary material is included to expand the utility of this document. Detailed three-language indexes (English-Latin-Chinese) allow ready identification and location of food items throughout all tables. Analytical methods used to obtain the data are described. Information is provided on the retention of vitamins in cooked foods, Chinese market units of weight and measure, and cooking and preparation techniques. A concluding discussion addresses the applicability and limitations of the tables, indicates statistical approaches to the data, and places this document in perspective with other food composition tables.
 
Article
Information is provided on the levels of four nutritional elements in 234 foods analyzed as part of the Food and Drug Administration′s Total Diet Study from 1982 to 1991. Median and Mean (± standard deviation) values are presented for the elements per 100g and per serving portion. Coefficients of variation (CVs) are also presented for the values per 100g. Major food group sources of the elements were dairy products, dairy-based desserts, and mixed dishes for calcium; nuts, mixed dishes, and bread, rolls, pasta, etc., for magnesium; ready-to-eat cereals, cooked grains, mixed dishes, and meat for iron; and meat, mixed dishes, and ready-to-eat cereals for zinc. There were 20 (9%), 19 (8%), and 28 (12%) foods containing ≥ 10% of the daily value (DV) for calcium, magnesium, iron, and zinc, respectively, per serving portion. The average CVs for foods containing ≥10% of the DV of these elements were 22% for calcium, 17% for magnesium, 28% for iron, and 22% for zinc.
 
Article
Information is provided on the levels of moisture, sodium, phosphorus, and potassium in 234 foods analyzed as part of the U.S. Food and Drug Administration′s Total Diet Study from 1982 to 1991. Median and mean (± standard deviation) values are presented for the elements per 100 g and per serving portion. Coefficients of variation (CVs) are also presented for the values per luncheon meats, and breads, rolls, pasta, etc., for sodium; mixed dishes, meat, dairy products, and poultry for phosphorus; and mixed dishes, root and tuber vegetables, beans and peas, and dairy products for potassium. Sodium Phosphorus, and potassium are widely distributed in Total Diet Study foods with 58 (25%), 61 (26%), and 31 (13%) foods, respectively, containing at least 10% of the daily value (DV) per serving portion. The average CVs for foods containing ≥ 10% of the DV of these elements were 21% for sodium, 15% for phophorus, and 16% for potassium.
 
Article
Information is provided on the levels of four elements in the 234 foods analyzed as part of the Food and Drug Administration′s Total Diet Study from 1982 to 1991. Median and Mean (± standard deviation) values are presented for the elements per 100g and per serving portion. Coefficients of variation (CVs) are also presented for the values per 100g. Major food group sources of the elements were meat, nuts, beans/peas, and mixed dishes for copper, ready-to-eat cereals, nuts, cooked grains, and beans/peas for manganese; fish, meat, poultry, and mixed dishes for selenium; and ready-to-eat cereals, mixed dishes, dairy-based desserts, fish, and dairy products for iodine. There were 16 (7%), 40 (17%), 48 (21%), and 81 (35%) foods containing ≥10% of the daily value (DV) or proposed DV for copper, manganese, selenium, and iodine, respectively, per serving portion. The average CVs for foods containing ≥10% of the DV of these elements were 24% for copper, 28% for manganese, 37% for selenium, and 158% for iodine. Because of their high variability, data on the iodine content of foods should be used with caution.
 
Article
Major Finnish and imported fruits and berries were examined for sugars and major organic acids simultaneously by gas chromatography. Apples, oranges, bananas, and grapes were obtained in 1987–1989 from wholesale outlets and strawberries, red currants, and black currants were obtained from the food industry. The results of the present study showed great variation in the sugar and organic acid contents of fruits and berries. The levels of sugars and organic acids were the same or lower than those reported in the literature. Sugar intake from fruits and berries is likely to vary considerably due to great variation of sugar content.
 
Article
Vegetables of domestic and foreign origin were obtained from large wholesale outlets in Southern and Central Finland in 1988–1989 and then analyzed for sugars and major organic acids simultaneously by gas chromatography. The results showed great variation in the sugar and organic acid contents of the vegetable samples. The sugar and organic acid contents of tomato and Chinese cabbage differed significantly (P < 0.05) between samples collected during different seasons. The malic acid content of cauliflower and the sugar contents of onion were significantly (P < 0.05) different between samples in different seasons. Average sugar concentrations of vegetables available in Finland were often lower than those reported in both the literature and the current food composition tables.
 
Article
Efforts to reduce the trend of increasing obesity in the United States should be more effective when informed by knowledge of the dietary patterns that are associated with this result. The purpose of this analysis is to describe the foods and food groups that contribute the most to population intake of energy. Two representative surveys were examined, the Third National Health and Nutrition Examination Survey (NHANES III), conducted in 1988–1994, and the NHANES from 1999–2000. All foods reported in these surveys were recoded into 144 food items. Foods were also further recoded into 23 food groups. Food items and groups were then ranked according to the proportion of total energy intake contributed by that food item or group. The #1 contributor of energy intake in both time periods was soft drinks, which contributed 7.1% of energy intake in 1999–2000. Among food groups, “Sweets, desserts” contributed the most to energy intake. Three nutrient-poor food groups, “Sweets, desserts”, “Soft drinks” and “Alcoholic beverages” contributed almost 25% of all the energy consumed in the US population. Efforts to reduce obesity should focus on both individual and policy actions to reduce the importance of nutrient-poor foods in the US diet.
 
Article
A novel headspace solvent microextraction (HSME) method for the extraction of trace amounts of 2,4-dimethylaniline (2,4-DMA), produced after hydrolysis of amitraz, is presented. The hydrolysis reaction and HSME were carried out in a single step, and then the preconcentrated 2,4-DMA was analyzed gas chromatographically using a thermionic specific detector (TSD). Different parameters affecting the HSME procedure including the type of solvent, headspace volume, stirring rate, Na2SO4 content, solution and microdrop temperature, drop volume and extraction time were studied and optimized. The optimized conditions were 25 min solution equilibrium time, 10 min solvent equilibrium time, 5 mL headspace volume, 600 rpm stirring rate, 15% Na2SO4, solution temperature 60 °C, microdrop temperature 4 °C and microdrop volume 3 μL. The limit of detection (LOD) and limit of quantification (LOQ) of the method were 10 and 30 ngamitraz g−1honey, respectively, and the dynamic linear range was from 0.03 to 10 μgamitraz g−1honey. Finally, the proposed method was applied to the quantification of amitraz in spiked honey samples. Because of performing hydrolysis and extraction processes in a single step, the method provided a rapid, simple and sensitive approach to analysis of amitraz.
 
Article
Using high-performance liquid chromatography (HPLC) and 2,4-dinitrophenylhydrazine as a derivatizing reagent, an analytical method has been developed for the analysis of ketones in hydro-alcoholic matrices, colored or not. The determination is carried out at 365 nm using a UV–Vis diode-array detector (DAD). For the ketones as their 2,4-dinitrophenylhydrazones, a good separation was achieved with a Supelco C18 column (25 cm×4.6 mm×5 μm) using a (methanol/acetonitrile)-water elution gradient. The methodology is simple, rapid, exhibits good reproducibility, and allows the analysis of both ketones and aldehydes in the same run. The application of this method to 34 sugar-cane spirits and 13 rums allowed the identification and quantification of acetone, acetophenone, cyclopentanone and 2,3-butanedione, at detection limits of 10 μg/l (2,3-butanedione) to 20 μg/l (cyclopentanone).
 
Article
The National Food and Nutrient Analysis Program (NFNAP) was designed in 1997 to develop robust and nationally representative estimates of the mean nutrient content of important foods in the food supply and significantly improve the quality of food composition data in the US Department of Agriculture's National Nutrient Databank. The underlying aims defining the process behind the NFNAP are: (1) evaluation of existing data; (2) identification of Key Foods and nutrients for analysis; (3) development of nationally based sampling plans; (4) analysis of samples; and (5) compilation and calculation of representative food composition data. Supported by a self-weighting stratified sampling design, the NFNAP approach has been applied to other sampling programs for the analysis of specific nutrients (e.g., fluoride-containing beverages and foods) and ethnic foods (e.g., American Indian foods). For select nutrients of potential health significance, additional sampling approaches allow for the estimation of serving-to-serving variability (e.g., highly processed foods). Under NFNAP, over 500 foods of the targeted 1000 important foods in the US food supply have been analyzed. Unrivaled research on food sampling, sample handling, and analytical methodology (e.g., for study of perishable nutrients in fresh produce) is integral to this effort. The NFNAP data are current, reflective of the market and nationally representative of the US food supply and therefore a crucial resource to health researchers, architects of nutrition policy, the nutrition and medical communities, and the food industry. They are released through the Web site: www.nal.usda.gov/fnic/foodcomp
 
Article
Roundup Ready™ (RR) soybean is the first genetically modified organism (GMO) approved in Brazil. In this country, the labeling of foodstuffs containing GMOs is mandatory if the GMO content exceeds 1% (10 g kg−1). In order to monitor and quantify the presence of RR soybean in soy-based and processed meat products on the Brazilian food market, DNA was extracted from 59 food samples and analyzed by polymerase chain reaction (PCR) to amplify the soybean lectin gene, and by nested PCR to amplify the recombinant DNA present in RR soybean. Positive samples for the presence of RR soybean were subjected to a real-time quantification of GMO using a duplex real-time PCR. The results showed that out of 59 samples, 54 were positive for lectin gene and six were positive for RR soybean, 5 samples contained less than10 g kg−1 GMO and one sample contained more than 10 g kg−1 GMO.
 
Article
This paper presents the results of an evaluation of chloramphenicol (CAP) levels in eight samples of propolis extracts considered to be the best-known brands of propolis specialities produced in Italy. The aim was to verify whether determination of CAP residues might be useful and appropriate in propolis derivatives in addition to other matrices previously studied. Hydroalcoholic and glycolic extract were simply diluted with ethyl acetate, and CAP was determined by monitoring the selective transition of two parent ions. These commercial products were analysed using liquid chromatography–tandem mass spectrometry method. Thiamphenicol as internal standard was used for quanitification. Detection of the analyte was achieved by negative ionization electrospray in the selected reaction monitoring (SRM) mode. For confirmation, two characteristic mass transitions were monitored, both for the analyte and the internal standard.
 
Article
Within EuroFIR, the European Food Information Resource (EuroFIR) project, the European Network of Excellence on Food Composition Databank systems, a standard recipe calculation procedure has been developed for use with European food composition databases. This project reviewed the most commonly used recipe calculation procedures together with the examples of recipe calculation procedures used by European databases. The review showed that the most commonly used method was a procedure that applies a yield factor for weight at the recipe level and retention factors for nutrient values at the ingredient level. This commonly used procedure was selected as the recommended EuroFIR recipe calculation procedure. The benefits of harmonised recipe calculation procedures include improved quality, availability and compatibility of food composition data through the documentation of the recipe ingredients, the recipe calculation procedures, yield factors and retention factors.
 
Article
The usefulness of food composition data at the level of the genetic resource (i.e. taxonomic level below species) is becoming increasingly acknowledged. Recent research has provided data to confirm the micronutrient superiority of some lesser-known cultivars and wild varieties over other, more extensively utilized cultivars. Sweet potato cultivars have been shown to differ in their carotenoid content by two orders of magnitude or more; protein content of rice varieties can range from 5 to 13%; provitamin-A carotenoid content of bananas can be less than 1 mcg/100 g for some cultivars to as high as 8500 mcg/100 g for other cultivars. Intake of one variety rather than another can be the difference between micronutrient deficiency and micronutrient adequacy. These data are important for the sectors of health, agriculture, trade and the environment. The importance of nutrition is now recognized by the Convention on Biological Diversity (CBD) and the Commission on Genetic Resources for Food and Agriculture. At the request of the CBD, FAO is leading the “Cross-cutting initiative on biodiversity for food and nutrition,” in collaboration with Bioversity International, and developing or improving compositional databases will form a significant part of the initiative. Once the data are prepared and compiled, they can be used in practically every domain of nutrition: nutrition education, community nutrition, nutrition interventions, food emergencies, nutritional labelling, food consumption surveys, to name but a few. These data should be “mainstreamed” into national and regional food composition databases giving recognition and importance to cultivars, varieties and breeds as foods in their own right.
 
Article
The leaves, seeds, flowers, and fruit of many indigenous plants are staples of populations who inhabit the Sahel region of Africa. They serve to supplement the nutrients provided by cereals such as millet and sorghum. However, there is a lack of comprehensive compositional data regarding the nutrient content of these indigenous plants. In this report, we present nutritional data for 24 plant materials collected in Burkina Faso, including their content of amino acids, fatty acids, and minerals. Three plants contained 20 to 37% protein (on a dry weight basis):Vigna sp., Hibiscus esculentus,andParkiia biglobosa.Relative to a WHO protein standard, three plants scored relatively high:Voadzeiia subterranea, Pennisetum americanum,andBixa orellana.Plants which contained large amounts of the essential fatty acids linoleic or α-linolenic acid wereVigna sp., Hibiscus esculentusseeds,Parkiia biglobosaseeds, andVitex donianafruit. Three plants were rich in iron:Adansonia digitata, Bixa orellana,andXylopia sp.The fruit and seeds ofHibiscus esculentuswere an excellent source of zinc. The plant foods with the highest calcium content wereAdansonia digitataleaves,Hibiscus sp.,andBombax costatum.These data show that in terms of both quality and quantity there are numerous spontaneous desert plants that can serve as significant sources of essential amino acids, essential fatty acids and trace minerals for populations living in the western Sahel.
 
Article
A rapid ultra-performance liquid chromatography (UPLC) method was developed for feasible separation and quantification of 26 amino acids in royal jelly. The analysis was performed on Acquity UPLC system with Acquity UPLC AccQ·Tag Ultra Column within 8 min. The correlation coefficient values (r2 > 0.9978) indicated good correlations between the investigated compounds’ concentrations and their peak areas within the test ranges. The limits of quantitation and detection of 26 amino acids were 42.7–235.1 ng/mL and 12.9–69.3 ng/mL, respectively. The recoveries ranged from 90.1% to 100.9% and the overall relative standard deviations for intra- and inter-day were lower than 2.8%. The results showed that UPLC was a powerful tool for the analysis of amino acids in royal jelly. The method was also applied to quantitatively determine free amino acid (FAA) and total amino acid (TAA) profiles in RJ samples stored at different temperatures (−18 °C, 4 °C and 25 °C) for different time intervals (1, 3, 6 and 10 months). Results showed that the average contents of FAA and TAA in fresh royal jelly were 9.21 mg/g and 111.27 mg/g, respectively; the major FAAs were Pro, Gln, Lys, Glu, and the most abundant TAAs were Asp, Glu, Lys and Leu. Although the concentration of most FAAs and TAAs showed no significant difference during storage, contents of total Met and free Gln decreased significantly and continuously, and might be a parameter to predict the quality of royal jelly.
 
Article
We report a 31P nuclear magnetic resonance (31P-NMR) investigation of buffalo milk, milk ultrafiltrate, and phospholipids from milk fat; for comparison corresponding data were also acquired for cow milk samples. In buffalo milk samples, we identified glycerophosphorylcoline, glycerophosphorylethanolamine and inorganic orthophosphate resonances, together with a broad peak assigned to serylphosphate residues of casein. Buffalo milk ultrafiltrate showed the presence of several phosporous signals, and ten of them (inorganic phosphate, phosphocreatine, glycerophosphorylcoline, glycerophosphorylethanolamine, N-acetylglucosamine-1-phosphate, glucose-6-phosphate, galactose-1-phosphate, phosphorylethanolamine, phosphorylcoline, and glycerol-1-phosphate) were unambiguously identified by addition of pure standards. In phospholipids fractions from buffalo milk, we clearly identified phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, sphingomyelin, and phosphatidylinositol. A preliminary estimation (mol%) of each phosphorylated compound was obtained. By comparing 31P-NMR data from milk samples from buffaloes and cows, we concluded that these milks are rather similar as far as the phosporous distribution in small molecules is concerned.
 
Article
A rapid gravimetric method for determining dietary fiber has enabled the repetitive analysis of 101 foods in a total diet study covering five Canadian cities. In the present work, 38 samples representing all categories of foods thought to contain dietary fiber were selected among the 101 foods. They were analyzed using the rapid method and two other recognized methods: the AOAC total dietary fiber method and the Englyst gas-chromatography method which measures the nonstarch polysaccharides (NSP). Dietary fiber values using the rapid method (y) and the AOAC method (x) were closely correlated (y = 1.02ξ – 0.13, r2 = 0.98, n = 38). The Englyst method was in agreement with the latter gravimetric methods for two-thirds of the foods and particularly the vegetables but yielded some lower values, mainly in cereal products. Adding lignin to NSP values improved the agreement between methods. Overall, the values using the rapid method (y) were closely correlated with those using the Englyst method plus lignin (x): y = 1.07ξ – 0.31, r2 = 0.96, n = 38. Results showed that the rapid method provides an accurate and quick estimation of dietary fiber in various foods. This method has been shown to have good precision in a recent collaborative study.
 
Article
Carmoisine (E 122), Ponceau 4R (E 124) and Allura red (E 129), are synthetic azo dyes 7generally used to give red colour to syrups, soda and sweets. They could be easily distinguished from the natural dyes, which are not electroactive, using differential pulse polarography. The influence of the pH on the intensities and the potentials of the peaks was studied between pH 3 and 11, and acidic or strongly basic media appeared not convenient. It was shown that in a pH=9 phosphate buffer, the peaks of Carmoisine, Allura red and Ponceau 4R were well shaped and separated, allowing accurate identification and quantification, even if the three dyes were mixed. No significant changes of the peak potentials were noticed in the commercial samples, and consequently the dyes can be identified without ambiguity. A procedure using the standard addition technique was validated with test syrups. The recovery was in the 96–105% range and the relative standard deviation was close to 1% for the three dyes. The limits of quantification in the polarographic cell, estimated from the polarographic data, were 42, 43 and 34 μg L−1 for Carmoisine, Allura red and Ponceau 4R, respectively. The method was applied to commercial soft drinks and sweets. The results were compared to those obtained using liquid chromatography, and they appeared to be in good agreement.
 
Article
Three sensitive and accurate methods for determination of Indigotin and Ponceau-4R in mixtures by Vierordt's method, ratio spectra first order derivative and first order derivative UV spectrophotometry are described. No separation step was required for these novel methods. Ratio spectra first order derivative and first derivative UV spectrophotometric methods were studied in the wavelength range of 300–700 nm and phosphate buffer pH 7.0 medium. The linearity ranges were found as 1.00–50.00 μg ml−1 for Indigotin and 1.00–52.00 μg ml−1 for Ponceau-4R dyes at developed UV spectrophotometric methods. In order to determine both dyes these procedures were applied to the commercially available food samples containing saccharose and citric acid such as powdered drinks, sweets and jellies. Developed spectrophotometric methods were found accurate, precise, reproducible, directly and easily applicable for the analysis of Indigotin and Ponceau-4R in food samples.The data obtained from these spectrophotometric methods to determine Indigotin and Ponceau-4R dyes in food were compared with data from HPLC methods which have been previously reported. No statistically significant difference was found between these methods.
 
Article
Two spectrophotometric methods have been described for determining Tartrazine and Ponceau-4R in binary mixtures. These methods permit the simultaneous determination of these food colorants in various commercially available food samples which contain saccharose and citric acid. Ratio spectra first-order derivative UV spectrophotometric method was studied in the wavelength range 300–700 nm and phosphate buffer pH 7.0 medium. The linearity range was found to be 1.00–60.00 μg mL−1 for Tartrazine and 1.00–52.00 μg mL−1 for Ponceau-4R dyes by Vierordt's and ratio spectra first-order derivative UV spectrophotometric methods. The values obtained from developed methods and the high-performance liquid chromatographic (HPLC) method given in the literature were compared. It was found that the difference was not statistically important between these methods. It was concluded that developed Vierordt's and ratio spectra first-order derivative UV spectrophotometric methods were accurate, sensitive, precise, reproducible and could be applied easily and directly to the routine analysis of the food samples.
 
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