Vitamin C loss was compared in homogenized raw broccoli, potatoes, spinach, strawberries, oranges... more Vitamin C loss was compared in homogenized raw broccoli, potatoes, spinach, strawberries, oranges, and tomatoes; baked potatoes; steamed broccoli and spinach; and pasteurized orange juice after storage under residual nitrogen under refrigeration, and frozen at conventional (−10 to −20 °C) and ultra-low (
Journal of Food Composition and Analysis, May 1, 2016
A wide range of nutrients and health-promoting non-nutrient components in mushrooms are a subject... more A wide range of nutrients and health-promoting non-nutrient components in mushrooms are a subject of international research, but specific reference materials to facilitate comparison of results among laboratories are lacking. Commercially available food matrix reference materials do not contain components unique to mushrooms (e.g., ergosterol, vitamin D 2 , chitin, beta-glucans, agaritine, ergothioneine). A Mixed Mushroom Control Material (CM) (homogeneous mixture of 15 types of mushrooms) was prepared and characterized for selected components, including proximates (moisture, protein, ash), total folate, folate vitamers, ergosterol, ergosterol metabolites, vitamin D 2 (ergocalciferol), amino acids, total dietary fiber, agaritine, elements (sodium, potassium, phosphorous, magnesium, calcium, iron, copper, manganese, zinc), riboflavin, niacin, thiamin, vitamin B6, pantothenic acid). Subsamples of the CM are available to qualified laboratories from the Food Analysis Laboratory Control Center at Virginia Tech (Blacksburg, VA, USA), to be assayed concurrently with mushroom samples for which food composition data will be published along with results for the CM. Implementation of this CM should facilitate comparison of published data on mushroom composition and health benefit among species, and biodiversity within species by serving as common control sample that allows the separation of analytical variability from true differences in sample composition determined at different laboratories.
Journal of the science of food and agriculture, Jan 6, 2018
Seasonal variation of vitamin C in fresh fruits and vegetables is not reflected in food compositi... more 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. Fresh fruits and vegetables were sampled on three occasions in each season, from the same local retail outlets, for one or two years. Vitamin C was significantly higher in winter-sampled spinach (436 mg kg-1 ) compared to spring (298) and summer/fall (180); in potatoes in summer/fall (156) versus winter/spring (106); and oranges in winter (616), spring (592), and summer (506). Ranges were dramatic among sampling occasions for broccoli, oranges, potatoes, spinach (700-1210, 420-780, 70-280, 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...
The US Department of Agriculture (USDA) Nutrient Data Laboratory (NDL) develops and maintains the... more 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 vitamin D2 content of white button mushrooms is relatively low. UV exposure produces vitamin ... more The vitamin D2 content of white button mushrooms is relatively low. UV exposure produces vitamin D2 by rapid conversion of ergosterol to ergocalciferol. Commercial-scale UV treatment has been used to produce vitamin D-enhanced mushrooms. The reliability of a consumer-friendly protocol to increase vitamin D2 in mushrooms by a nutritionally meaningful amount using exposure to sunlight was evaluated. Sliced white button mushrooms were exposed to sunlight for 15, 30, or 60 minutes in 16 experiments at different times of day, seasons, and cloud cover. Vitamin D2 was measured by HPLC with 3H-vitamin D3 internal standard. Change in vitamin D2 per 70 g serving relative to untreated mushrooms was evaluated. Vitamin D2 in all unexposed mushrooms was <30 IU/70 g (<5%DRI) (median, <7 IU/70 g). Regardless of season, treatment for 15 minutes between 9:30 a.m. and 3:30 p.m. under partly cloudy to clear conditions increased vitamin D2 by157-754 IU/70 g (26-126%DRI), and up to 1142 IU/70 g ...
Journal of food composition and analysis : an official publication of the United Nations University, International Network of Food Data Systems, 2010
The National Food and Nutrient Analysis Program (NFNAP) was implemented in 1997 to update and imp... more 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-...
The role of fluoride in reducing the risk of dental caries, especially among children, is well re... more The role of fluoride in reducing the risk of dental caries, especially among children, is well recognized and is the basis for current intake recommendations.
Purpose Significant differences may occur in the nutrient content of different edible portions ... more Purpose Significant differences may occur in the nutrient content of different edible portions of vegetables and fruits. The purpose of this study was to screen the folate content of different edible portions of some common fruits and vegetables. Design/methodology/approach 5-...
Beef and beef fat control composites (CC) were prepared for a large multi-year study of conjugate... more Beef and beef fat control composites (CC) were prepared for a large multi-year study of conjugated linoleic acid (CLA) and trans-vaccenic acid (TVA) in beef. Raw ground beef and beef suet were each frozen in liquid nitrogen, ground to a fine powder, dispensed into subsamples, and stored at − 60°C under nitrogen. The CCs, reference materials (beef/pork fat; meat homogenate), and standards prepared at two concentrations of CLA and TVA added to a total lipid extract of beef (differing by 0.27 g/100 g CLA and 1.2432 g/100 g TVA) were analyzed via alkaline saponification of lipids, derivatization to fatty acid methyl esters, and GC. CLA and TVA recoveries from the standards were 95-113% (CLA) and 103-106% (TVA). Fatty acids quantified in the reference materials were within the certified ranges. Relative standard deviations (n = 3 in each of 5 assay batches) were b 5% (TVA) and b 10% (CLA) for both CCs, at both laboratories.
Vitamin C loss was compared in homogenized raw broccoli, potatoes, spinach, strawberries, oranges... more Vitamin C loss was compared in homogenized raw broccoli, potatoes, spinach, strawberries, oranges, and tomatoes; baked potatoes; steamed broccoli and spinach; and pasteurized orange juice after storage under residual nitrogen under refrigeration, and frozen at conventional (−10 to −20 °C) and ultra-low (
Journal of Food Composition and Analysis, May 1, 2016
A wide range of nutrients and health-promoting non-nutrient components in mushrooms are a subject... more A wide range of nutrients and health-promoting non-nutrient components in mushrooms are a subject of international research, but specific reference materials to facilitate comparison of results among laboratories are lacking. Commercially available food matrix reference materials do not contain components unique to mushrooms (e.g., ergosterol, vitamin D 2 , chitin, beta-glucans, agaritine, ergothioneine). A Mixed Mushroom Control Material (CM) (homogeneous mixture of 15 types of mushrooms) was prepared and characterized for selected components, including proximates (moisture, protein, ash), total folate, folate vitamers, ergosterol, ergosterol metabolites, vitamin D 2 (ergocalciferol), amino acids, total dietary fiber, agaritine, elements (sodium, potassium, phosphorous, magnesium, calcium, iron, copper, manganese, zinc), riboflavin, niacin, thiamin, vitamin B6, pantothenic acid). Subsamples of the CM are available to qualified laboratories from the Food Analysis Laboratory Control Center at Virginia Tech (Blacksburg, VA, USA), to be assayed concurrently with mushroom samples for which food composition data will be published along with results for the CM. Implementation of this CM should facilitate comparison of published data on mushroom composition and health benefit among species, and biodiversity within species by serving as common control sample that allows the separation of analytical variability from true differences in sample composition determined at different laboratories.
Journal of the science of food and agriculture, Jan 6, 2018
Seasonal variation of vitamin C in fresh fruits and vegetables is not reflected in food compositi... more 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. Fresh fruits and vegetables were sampled on three occasions in each season, from the same local retail outlets, for one or two years. Vitamin C was significantly higher in winter-sampled spinach (436 mg kg-1 ) compared to spring (298) and summer/fall (180); in potatoes in summer/fall (156) versus winter/spring (106); and oranges in winter (616), spring (592), and summer (506). Ranges were dramatic among sampling occasions for broccoli, oranges, potatoes, spinach (700-1210, 420-780, 70-280, 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...
The US Department of Agriculture (USDA) Nutrient Data Laboratory (NDL) develops and maintains the... more 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 vitamin D2 content of white button mushrooms is relatively low. UV exposure produces vitamin ... more The vitamin D2 content of white button mushrooms is relatively low. UV exposure produces vitamin D2 by rapid conversion of ergosterol to ergocalciferol. Commercial-scale UV treatment has been used to produce vitamin D-enhanced mushrooms. The reliability of a consumer-friendly protocol to increase vitamin D2 in mushrooms by a nutritionally meaningful amount using exposure to sunlight was evaluated. Sliced white button mushrooms were exposed to sunlight for 15, 30, or 60 minutes in 16 experiments at different times of day, seasons, and cloud cover. Vitamin D2 was measured by HPLC with 3H-vitamin D3 internal standard. Change in vitamin D2 per 70 g serving relative to untreated mushrooms was evaluated. Vitamin D2 in all unexposed mushrooms was <30 IU/70 g (<5%DRI) (median, <7 IU/70 g). Regardless of season, treatment for 15 minutes between 9:30 a.m. and 3:30 p.m. under partly cloudy to clear conditions increased vitamin D2 by157-754 IU/70 g (26-126%DRI), and up to 1142 IU/70 g ...
Journal of food composition and analysis : an official publication of the United Nations University, International Network of Food Data Systems, 2010
The National Food and Nutrient Analysis Program (NFNAP) was implemented in 1997 to update and imp... more 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-...
The role of fluoride in reducing the risk of dental caries, especially among children, is well re... more The role of fluoride in reducing the risk of dental caries, especially among children, is well recognized and is the basis for current intake recommendations.
Purpose Significant differences may occur in the nutrient content of different edible portions ... more Purpose Significant differences may occur in the nutrient content of different edible portions of vegetables and fruits. The purpose of this study was to screen the folate content of different edible portions of some common fruits and vegetables. Design/methodology/approach 5-...
Beef and beef fat control composites (CC) were prepared for a large multi-year study of conjugate... more Beef and beef fat control composites (CC) were prepared for a large multi-year study of conjugated linoleic acid (CLA) and trans-vaccenic acid (TVA) in beef. Raw ground beef and beef suet were each frozen in liquid nitrogen, ground to a fine powder, dispensed into subsamples, and stored at − 60°C under nitrogen. The CCs, reference materials (beef/pork fat; meat homogenate), and standards prepared at two concentrations of CLA and TVA added to a total lipid extract of beef (differing by 0.27 g/100 g CLA and 1.2432 g/100 g TVA) were analyzed via alkaline saponification of lipids, derivatization to fatty acid methyl esters, and GC. CLA and TVA recoveries from the standards were 95-113% (CLA) and 103-106% (TVA). Fatty acids quantified in the reference materials were within the certified ranges. Relative standard deviations (n = 3 in each of 5 assay batches) were b 5% (TVA) and b 10% (CLA) for both CCs, at both laboratories.
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