Plant sterols in vegetables and fruits commonly consumed in Sweden

Summary Plant sterols are known to have serum cholesterol lowering effects. A high dietary intake might therefore have a positive impact on health. All food items of vegetable origin contain some amount of plant sterols. The aim of this study was to analyse the plant sterol content of vegetables and fruits commonly consumed in Sweden, and to compare fresh and cooked samples of the same items. Altogether 20 different vegetables and 14 fruits were analysed. All vegetables and fruits were purchased in two shops in the city of Gothenburg, Sweden. Lyophilization was performed within one month of the items being purchased. The samples were frozen at −20 (C and analysed within six months, with a GLC method after acid hydrolysis, alkaline hydrolysis and silylation with tri-methylsilylether. The acid hydrolysis was done in order to detect the fraction of glycosylated plant sterols, which are split during boiling with HCl. The median plant sterol content of vegetables was 14 (3.8–50) mg/100 g edible portion. The highest concentrations were found in broccoli, Brussels sprouts, cauliflower and olives. The median plant sterol content of fruits was 16 (3–44) mg/100 g edible portion. The highest concentrations were found in oranges and passion fruits. The plant sterol concentrations were thus low in vegetables and fruits commonly consumed in Sweden. A serum cholesterol lowering effect attributed to the plant sterols in vegetables and fruits would therefore be of limited significance. Received: 25 September 1998, Accepted: 10 February 1999     

Antioxidant activity of commonly consumed plant foods of India: contribution of their phenolic content

Antioxidants are important in protection against hypertension, diabetes, cardiovascular diseases and cancer. Polyphenols are potent antioxidants in plant foods, but their contribution to such protective effects is yet to be established. This study attempted to generate a database on the antioxidant activity (AOA) and phenolic content (PC) of some plant foods commonly consumed in India and to assess the contribution of the PC to their AOA. Plant foods belonging to different food groups such as cereals, legumes, oil seeds, oils, green leafy vegetables, other vegetables, spices, roots and tubers were analysed for AOA and PC. AOA was the highest in black pepper (0.43 mg food required for 50% inhibition of the coupled auto-oxidation of β-carotene and linoleic acid in a mixture in vitro) and it had the highest PC (191 mg gallic acid equivalent/100 g food). The AOA (18.4 mg) as well as the PC (not detectable) were the lowest in sunflower oil. PC in oil seeds was higher than that in the oil, which could be due to the hydrophilic nature of phenolics and suggests the need for greater use of oil seeds than oils. A significant correlation was observed between the AOA and PC of the plant foods studied in general (r=?0.465), but the coefficient of correlation and determination were high only in spices (r=?0.86 and r²=74%, respectively) and dehusked legumes (r=?0.65 and r²=42.2%, respectively). The results suggest that phenolics may contribute significantly to the AOA of some plant foods, such as spices and dehusked legumes.     

Antioxidant activity of commonly consumed plant foods of India: contribution of their phenolic content

Antioxidants are important in protection against hypertension, diabetes, cardiovascular diseases and cancer. Polyphenols are potent antioxidants in plant foods, but their contribution to such protective effects is yet to be established. This study attempted to generate a database on the antioxidant activity (AOA) and phenolic content (PC) of some plant foods commonly consumed in India and to assess the contribution of the PC to their AOA. Plant foods belonging to different food groups such as cereals, legumes, oil seeds, oils, green leafy vegetables, other vegetables, spices, roots and tubers were analysed for AOA and PC. AOA was the highest in black pepper (0.43 mg food required for 50% inhibition of the coupled auto-oxidation of beta-carotene and linoleic acid in a mixture in vitro) and it had the highest PC (191 mg gallic acid equivalent/100 g food). The AOA (18.4 mg) as well as the PC (not detectable) were the lowest in sunflower oil. PC in oil seeds was higher than that in the oil, which could be due to the hydrophilic nature of phenolics and suggests the need for greater use of oil seeds than oils. A significant correlation was observed between the AOA and PC of the plant foods studied in general (r=-0.465), but the coefficient of correlation and determination were high only in spices (r=-0.86 and r2 =74%, respectively) and dehusked legumes (r=-0.65 and r2 = 42.2%, respectively). The results suggest that phenolics may contribute significantly to the AOA of some plant foods, such as spices and dehusked legumes.     

Change in the ascorbic acid, total phenol and antioxidant activity of sun-dried commonly consumed green leafy vegetables in Nigeria

Sun-drying of green leafy vegetables is popularly practised in many homes in Nigeria, as a way of preserving green leafy vegetables for future use. This project sought to investigate the effect of this method of preservation of vegetables on the antioxidant phytoconstituent (Vitamin C and Total phenol) and activity (reducing property and free radical scavenging ability) of some commonly consumed green leafy vegetables in Nigeria namely Structium sparejanophora (Ewuro-odo), Amarantus cruentus (Atetedaye), Telfairia occidentalis (Ugu), Baselia allia (Amunu tutu), Solanum macrocarpon (Igbagba), Corchorus olitorius (Ewedu), Vernonia anygdalina (Ewuro) and Occimum graticimum (Efinrin). The edible portions of the green leafy vegetables were sun-dried for seven days before determining the Vitamin C and total phenol content, as well as the reducing property and free radical scavenging ability. The result of the study revealed that sun-drying of green leafy vegetables cause a significant (P < 0.05) decrease in the Vitamin C content (16.67-64.68% loss). Conversely it leads to a significant increase in the total phenol content (6.45-223.08% gain), reducing property (16.00-362.50% gain) and free radical scavenging ability (126.00-5757.00% gain) of the green leafy vegetables. It could therefore be concluded that a significant decrease (P < 0.05) in Vitamin C content caused by sun- drying will not reduce the antioxidant activity of the green leafy vegetable, moreover, the phenol constituent of the green leafy vegetables contributes more to the antioxidant properties of vegetables than ascorbic acid, as its increase on sun-drying cause a significant (P < 0.05) increases in the antioxidant properties of the green leafy vegetables, irrespective of the decrease in the ascorbic acid content.     

Quantitative analysis of nitrate and nitrite contents in vegetables commonly consumed in Delta State, Nigeria

Plasma thiocyanate has been reported to be high among cassava-eating populations such as that in Nigeria because of the cyanide content of cassava. Thiocyanate, which is secreted into the stomach contents of animals, has been demonstrated to catalyse the formation of nitrosamines (potent carcinogens) in the stomach from secondary amines and nitrite. The main source of the nitrite precursor in this environment is vegetables, primarily eaten as the chief supplier of proteins. The present study attempts to analyse the levels of nitrate and nitrite in vegetables commonly grown and consumed in Delta State, Nigeria. The nitrate and nitrite contents in green vegetable (Amaranthus spp.), bitter leaf (Vernonia amygdalina), pumpkin (Telfaria occidentalis) and water leaf (Talinum triangulare) grown in different localities of the state were determined by standard analytical procedures. The results show that those vegetables grown in the industrialised urban centres of the state had higher nitrate (223 (SD 71) mg/kg dry weight; P<0.05) and nitrite (12.6 (SD 1.7) mg/kg dry weight; P>0.05) levels when compared with the same species (188 (SD 77) mg nitrate/kg dry weight and 10.9 (SD 1.1) mg nitrite/kg dry weight) cultivated in less industrialised suburbs. We conclude that frequent consumption of such vegetables whose nitrate and nitrite contents are high by cassava-eating individuals might put them at risk of developing stomach cancer and other possible results of nitrate and/or nitrite toxicity. In order to avoid an outbreak in our communities, appropriate agencies should monitor and regulate the release of chemicals into the environment. In the meantime, the cultivation and consumption of vegetables grown in industrialised areas of the state should be discouraged.     

Taste-nutrient relationships in commonly consumed foods

Taste is expected to represent a food's nutrient content. The objective was to investigate whether taste acts as nutrient-sensor, within the context of the current diet, which is high in processed foods. Intensities of the five basic tastes of fifty commonly consumed foods were rated by nineteen subjects (aged 21·0 (SD 1·7) years, BMI 21·5 (SD 2·0) kg/m(2)). Linear regression was used to test associations between taste and nutrient contents. Food groups based on taste were identified using cluster analysis; nutrient content was compared between food groups, using ANOVA. Sweetness was associated with mono- and disaccharides (R(2) 0·45, P < 0·01). Saltiness and savouriness were correlated, with r 0·92 (P < 0·01) and both were associated with Na (both: R(2) 0·33, P < 0·01) and protein (R(2) 0·27, P < 0·01 and R(2) 0·33, P < 0·01, respectively). Cluster analysis indicated four food groups: neutral, salty and savoury, sweet-sour and sweet foods. Mono- and disaccharide content was highest in sweet foods (P < 0·01). In salty and savoury foods, protein content (P = 0·01 with sweet-sour foods, not significant with neutral or sweet foods) and Na content (P < 0·05) were the highest. Associations were more pronounced in raw and moderately processed foods, than in highly processed foods. The findings suggest that sweetness, saltiness and savouriness signal nutrient content, particularly for simple sugars, protein and Na. In highly processed foods, however, the ability to sense nutrient content based on taste seems limited.     

Potential of commonly consumed green leafy vegetables for their antioxidant capacity and its linkage with the micronutrient profile

Green leafy vegetables (GLV) offer a cheap but rich source of a number of micronutrients and other phytochemicals having antioxidant properties. The potential of 30 GLV in the raw and cooked form as natural antioxidant supplements for vegetarian diets was assessed. There was a large variability in the values of antioxidant activity of various GLV extracts in the lipid micelles (1.5-5.6 mM vitamin E/100 g for raw samples and 1.6-3.8 mM vitamin E/100 g for cooked samples). Similar to thiobarbituric acid reactive substances values, the super oxide scavenging ability values also exibited large variation (10.6-55.9), with significantly higher values in the raw state than the cooked state (P<0.001). Omum leaves, radish leaves and lettuce had high values for this index. The range of values for ferrous iron chelating activity was from 9.3 to 65.7 mM EDTA/100 g food material, indicating again a large variability in this assay. Leaves of coriander, amaranthus viridis, colcasia green and drumstick showed high values, while Amaranthus p. Colocasia black and amaranthus red exibited low values. Differences between raw and cooked values were highly significant for all the three indices (P<0.001).     

Application of principal component and hierarchical cluster analysis to classify fruits and vegetables commonly consumed in Ireland based on in vitro antioxidant activity

The purpose of this study was to gain insights into the variations in antioxidant profiles between fruits and vegetables using pattern recognition tools; classification was achieved based on global antioxidant activity, levels of antioxidant groups (total phenolics, total anthocyanins, ascorbic acid) and quality parameters (instrumental colour, moisture). Six vegetables (broccoli, carrot [organic and intensively grown], butterhead lettuce, red onion, yellow onion) and eight fruits (blueberries, cherry tomato, cranberries, red grapes, green pepper, raspberry, red pepper and strawberry) commonly consumed in Ireland were analysed. Antioxidant activity (ARP) and concentrations of bioactive compound groups differed according to sample type. Berry fruits had the highest antioxidant activity (1.51-2.97 (g/L)⁻¹). By contrast, vegetables were quite low in antioxidant activity (0.14-0.39 (g/L)⁻¹). Interrelationships between the parameters analysed and the different fruits and vegetables were investigated by principal component analysis (PCA) and hierarchical cluster analysis (HCA). PCA revealed that the first two components represented 62% of the total variability in antioxidant activity and different antioxidant groups. HCA classified samples into four main groups on the basis of the measured parameters.     

Advanced glycoxidation end products in commonly consumed foods

OBJECTIVE: Advanced glycoxidation end products (AGEs), the derivatives of glucose-protein or glucose-lipid interactions, are implicated in the complications of diabetes and aging. The objective of this article was to determine the AGE content of commonly consumed foods and to evaluate the effects of various methods of food preparation on AGE production. DESIGN: Two-hundred fifty foods were tested for their content in a common AGE marker (epsilon)N-carboxymethyllysine (CML), using an enzyme-linked immunosorbent assay based on an anti-CML monoclonal antibody. Lipid and protein AGEs were represented in units of AGEs per gram of food. RESULTS: Foods of the fat group showed the highest amount of AGE content with a mean of 100+/-19 kU/g. High values were also observed for the meat and meat-substitute group, 43+/-7 kU/g. The carbohydrate group contained the lowest values of AGEs, 3.4+/-1.8 kU/g. The amount of AGEs present in all food categories was related to cooking temperature, length of cooking time, and presence of moisture. Broiling (225 degrees C) and frying (177 degrees C) resulted in the highest levels of AGEs, followed by roasting (177 degrees C) and boiling (100 degrees C). CONCLUSIONS: The results indicate that diet can be a significant environmental source of AGEs, which may constitute a chronic risk factor for cardiovascular and kidney damage.     

Potential of commonly consumed green leafy vegetables for their antioxidant capacity and its linkage with the micronutrient profile

Green leafy vegetables (GLV) offer a cheap but rich source of a number of micronutrients and other phytochemicals having antioxidant properties. The potential of 30 GLV in the raw and cooked form as natural antioxidant supplements for vegetarian diets was assessed. There was a large variability in the values of antioxidant activity of various GLV extracts in the lipid micelles (1.5–5.6 mM vitamin E/100 g for raw samples and 1.6–3.8 mM vitamin E/100 g for cooked samples). Similar to thiobarbituric acid reactive substances values, the super oxide scavenging ability values also exibited large variation (10.6–55.9), with significantly higher values in the raw state than the cooked state (P<0.001). Omum leaves, radish leaves and lettuce had high values for this index. The range of values for ferrous iron chelating activity was from 9.3 to 65.7 mM EDTA/100 g food material, indicating again a large variability in this assay. Leaves of coriander, amaranthus viridis, colcasia green and drumstick showed high values, while Amaranthus p. Colocasia black and amaranthus red exibited low values. Differences between raw and cooked values were highly significant for all the three indices (P<0.001).     

Glycemic index of potatoes commonly consumed in North America

OBJECTIVE: To determine the effect of variety and cooking method on glycemic response and glycemic index of common North American potatoes. DESIGN: Study 1: subjects consumed 200 g Russet or white potatoes that were either (a) precooked, refrigerated, and reheated (precooked) or (b) cooked and consumed immediately (day-cooked). Incremental area under the curve was determined. Study 2: subjects consumed 50 g carbohydrate portions of white bread or potatoes (six different varieties and two different cooking methods). Glycemic index values were calculated. In both studies meals were consumed after a 10- to 12-hour overnight fast and finger-prick capillary-blood glucose was measured before and at intervals for 2 hours after consumption. SUBJECTS: The study groups were as follows: Study 1 comprised four men and six women, aged 20 to 44 and Study 2 comprised 11 men and one woman, aged 18 to 50. STATISTICAL ANALYSES: Repeated measures analysis of variance with Newman-Kuels to protect for multiple comparisons (criterion of significance two-tailed P <.05). RESULTS: Study 1: Precooked Russet potatoes elicited lower area under the curve than day-cooked (P <.05), while precooking had no effect on boiled white potatoes. Study 2: The glycemic index values of potatoes varied significantly, depending on the variety and cooking method used (P =.003) ranging from intermediate (boiled red potatoes consumed cold: 56) to moderately high (roasted California white potatoes: 72; baked US Russet potatoes: 77) to high (instant mashed potatoes: 88; boiled red potatoes: 89). CONCLUSIONS: The glycemic index of potatoes is influenced by variety and method of cooking and US Russet potatoes have only a moderately high glycemic index. Individuals who wish to minimize dietary glycemic index can be advised to precook potatoes and consume them cold or reheated.     

Nutritional composition of commonly consumed traditional Apache foods in Arizona

PRIMARY OBJECTIVE: To provide nutritional composition data for commonly consumed traditional Apache foods to enable an assessment of dietary intake and to evaluate a food-store based intervention aimed at reducing risk of chronic disease. METHODS AND PROCEDURES: Weighed recipes were collected in Apache households on the White Mountain Apache reservation in Arizona. The nutritional composition was calculated using the U.S. Department of Agriculture National Nutrient Database. MAIN OUTCOMES AND RESULTS: A total of 47 weighed recipes were collected for 13 traditional Apache dishes; five were breads, five were chicken or meat-based stews, two were tortilla-based dishes and the remaining one was a traditional Indian dumpling. The calculated energy, macronutrient content and micronutrient content of these traditional foods are provided. CONCLUSIONS: We have provided for the first time the nutritional composition per 100 g for 13 traditional Apache foods. These data are essential for determining dietary intake and diet-disease associations and for developing and evaluating the effectiveness of a food-store-based intervention in this population.     

Hydrophilic antioxidant capacities of vegetables and fruits commonly consumed in Japan and estimated average daily intake of hydrophilic antioxidants from these foods

The sum of hydrophilic antioxidants of 23 vegetables and 13 fruits commonly consumed in Japan was evaluated by a modified hydrophilic-oxygen radical absorbance capacity (H-ORAC) method. The “typical vegetable” and “typical fruit” in Japan contained hydrophilic antioxidants that are equivalent to 6.95 and 12.23 μmol of Trolox per g of the edible portion, respectively, on average. Hence, the daily intake of hydrophilic antioxidants from vegetables and fruits was estimated to be 4423 μmol Trolox equivalent (TE)/d based on data of the National Health and Nutrition Survey in Japan. However, the biological significance of these antioxidant values has not yet been clarified. To address this issue, our data will provide a foundation for high-quality epidemiological studies aimed at elucidating the relationship between daily intake of antioxidants and health. In addition, the comparison of the results of the H-ORAC assay with those of polyphenol content and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay was also studied. The H-ORAC values had a strong positive correlation with polyphenol contents (r = 0.956), and were 1.0–18.2-times higher than the antioxidant capacities evaluated by the DPPH assay.     

Tocopherol and carotenoid content of foods commonly consumed in Costa Rica

This article presents the first Costa Rican database on food carotenoids and tocopherols. The report concerning the content of these nutrients in foods that are common to the Latin American diet and to native Costa Rican varieties and cultivars is particularly important. Celery, which includes the leaves in Costa Rica, shows the highest content of lutein + zeaxanthin (26,400 μg/100 g) and β-carotene (16,200 μg/100 g), and is ranked fourth as a source of α-carotene (168 μg/100 g). The amount of lutein + zeaxanthin and β-cryptoxanthin present in Costa Rican red peppers is significantly high (2600 and 730 μg/100 g, respectively) and the amount of lycopene provided by 100 g of sardines canned in tomato sauce is higher (3300 μg/100 g) than the same amount of home-style tomato sauce (1420 μg/100 g) or raw tomato (1260 μg/100 g). Soybean oil has the highest δ-tocopherol content of all oils and is second to corn oil in γ-tocopherol content. Olive and sunflower oil have the highest α-tocopherol content. However, the content of α-tocopherol in celery and broccoli stands out. On average, these vegetables provide only 3 mg/100 g less of α-tocopherol than sunflower oil (12 mg/100 g and 15 mg/100 g, respectively). The reported data, together with the recently published Brazilian database on food carotenoids, could be the first step towards the systematic development of a Latin America carotenoid and tocopherol food composition database.     

Total folate: diversity within fruit varieties commonly consumed in India

Folate concentrations in selected fruits were measured using the trienzyme extraction and microbiological assay with Lactobacillus casei (subsp. Rhamnosus) as an assay organism. Fruits were purchased from different retail outlets at Coimbatore, Tamilnadu, India and were analyzed for total folate content. The folate content in all fruits varied considerably on a fresh weight basis from 10 to 328 μg/100 g, with tropical fruits ranging between 10 and 211 μg/100 g, temperate fruits from 11 to 328 μg/100 g, and the subtropical fruits in the range of 9–237 μg/100 g. Amongst all fruits, plum had the highest content of folate (328 μg/100 g). Data analyzed will assist dietary studies to estimate and evaluate the adequacy of folate intakes of the population, to formulate experimental diets for folate bioavailability studies, and to revise dietary recommendations for the population. In addition, the data will assist the health authorities in planning and executing strategies for intervention programs.     

Salt content of ready meals commonly consumed by older people

Background:  It is well documented that blood pressure increases with age and is commonly related to sodium intake (Intersalt, 1988). In an earlier study, McCabe & Thomas (2007) suggested that frequent use of ready meals among single elderly men may be associated with higher intakes of fat and salt. Ready meals are increasingly popular in the UK, accounting for some £2.38bn of food expenditure and consequently the salt content of those commonly used by older people is of considerable interest from a public health perspective.
Methods:  Eighty people aged over 65 years (20 male, 60 female) attending three Age Concern centres in London were interviewed concerning their eating habits and use of ready meals. From this information, the 20 most popular types of ready meals were identified. Packaging information was then collected, concerning the portion weight, salt and energy content of these ready meal dishes as provided by 10 different manufacturers.
Results:  Portion sizes varied widely. Table 1 shows salt per serving, salt per 100 g and mean g salt per serving as % of the recommended daily maximum RDM (6 g salt).  

  Table 1  Salt content of ready meals commonly eaten by older people     

19.

Carotenoids and total phenolic contents in plant foods commonly consumed in Korea     

Gun-Ae Yoon  Kyung-Jin Yeum  Yoon-Suk Cho  C-Y. Oliver Chen  Guangwen Tang  Jeffrey B. Blumberg  Robert M. Russell  Sun Yoon  Yang Cha Lee-Kim 《Nutrition Research And Practice》2012,6(6):481-490

     

20.

Most commonly consumed foods and food perceptions in Native American women     

Taylor CA  Keim KS  Gilmore AC  Parker SP  Van Delinder JL 《American journal of health behavior》2006,30(6):613-625

OBJECTIVE: To identify commonly consumed foods and the relationship of health perception on food intakes. METHODS: One hundred seventy-five Native American women completed a 1-d or 4-d food records. Perceptions of health value were obtained by the food sort method. Frequency analyses identified commonly consumed foods. Relations between intakes and perception of health value were evaluated by Spearman's correlations. RESULTS: Coffee and tea, soda (diet and regular), white bread, and table fats were the most commonly consumed foods in both samples. Health value had little impact on consumption. CONCLUSIONS: Understanding the foods consumption and the role of perception on intakes allows for targeted nutrition education programming.     

Most commonly consumed foods and food perceptions in Native American women

OBJECTIVE: To identify commonly consumed foods and the relationship of health perception on food intakes. METHODS: One hundred seventy-five Native American women completed a 1-d or 4-d food records. Perceptions of health value were obtained by the food sort method. Frequency analyses identified commonly consumed foods. Relations between intakes and perception of health value were evaluated by Spearman's correlations. RESULTS: Coffee and tea, soda (diet and regular), white bread, and table fats were the most commonly consumed foods in both samples. Health value had little impact on consumption. CONCLUSIONS: Understanding the foods consumption and the role of perception on intakes allows for targeted nutrition education programming.