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This two-year study compared the status of targeted nutrients in selected fresh and frozen fruits and vegetables. In addition, a novel third category was examined—a “fresh-stored” categorization intended to mimic typical consumer storage patterns of produce following purchase (five days of refrigeration). Broccoli, cauliflower, corn, green beans, green peas, spinach, blueberries, and strawberries of all three categories of freshness were analyzed for their concentrations of l-ascorbic acid (vitamin C), trans-β-carotene (provitamin A), and total folate. Analyses were performed in triplicate on representative samples using standardized analytical methods and included a quality control plan for each nutrient. In the majority of comparisons between nutrients within the categories of fresh, frozen, and “fresh-stored”, the findings showed no significant differences in assessed vitamin contents. In the cases of significant differences, frozen produce outperformed “fresh-stored” more frequently than “fresh-stored” outperformed frozen. When considering the refrigerated storage to which consumers may expose their fresh produce prior to consumption, the findings of this study do not support the common belief of consumers that fresh food has significantly greater nutritional value than its frozen counterpart.

Three composites of human milk samples were subjected to different processing conditions: (1) deaerated, vacuum packaged in metalized polyester bags and pasteurized at 56°C for 8 min; (2) vacuum packaged and pasteurized; (3) vacuum packaged. On days 0, 4, 7, 14, 28, 64, and 96 of storage, each treatment was analyzed for dissolved oxygen content and viable microflora. On days 0, 4, and 14, randomly selected isolates from each treatment were identified to the species level. Heat treatment of the milk samples reduced the number of viable microorganisms and resulted in a shift in the type of bacteria in the milk. Pasteurized samples contained primarily non-pathogenic skin commensals, while non-pasteurized samples were populated by species of Pseudomonas and other Gram negative microorganisms, including potential pathogens. Deaeration did not affect either the number or types of microorganisms surviving the heat treatment.

The bacteriological profiles of human milk samples collected from individual donors under supervised conditions of collection were compared to pooled human milk samples obtained from a commercial human milk bank. Total aerobic counts and total coliform counts of individual donor samples were lower than those of pooled, banked human milk. All of the 200 isolates from ten individual samples were staphylococci with Staphylococcus epidermidis predominating (82%). Only 1% of the isolates was identified as Staphylococcus aureus . Forty-two percent of the 100 isolates from five pooled samples were staphylococci and all of these staphylococci were coagulase-negative. Three percent of the isolates from the pooled samples were Streptococcus faecalis . The remainder (55%) were gram-negative organisms. S. epidermidis was the microorganism that was isolated most frequently from either individual (9 of 10) or pooled (3 of 5) samples.

A continuous flow high-temperature short-time pasteurization system was used to determine kinetic parameters (D- and z-values) for thermal destruction of the bacterial pathogens, Escherichia coli and Klebsiella pneumoniae , in mature human milk. D-and z-alues of each bacterium were determined from data on survivors enumerated on both selective media, Violet Red Bile agar or MacConkey's, and on a non-selective medium, nutrient agar (NA). For E. coli , D-values were determined at 58, 60, 62 and 64°C. The predicted value of D at 60°C is 31.5 s. The z-value for E. coli is 3.2°C. D-values for K. pneumoniae were determined at 52, 56 and 58°C. Based on these data the predicted value of D at 60°C is 1.3 s. The z-value for K. pneumoniae , is 2.8°C. For both E. coli and K. pneumoniae , counts on NA tend to be higher than on selective media. This is undoubtedly due to the inhibitory nature of the selective media. This also suggests that some degree of thermal injury may occur for each organism.

The total IgA, IgG, IgM and lactoferrin concentrations in human milk from 89 donors were studied at three lactational stages: early transitional (3 to 8 d postpartum), transitional (10 to 14 d postpartum) and mature (30 to 47 d postpartum). The effects of processing and storage on these components in composite samples of mature human milk were determined. There were no significant diurnal variations in any of the four protective factors at either the transitional or mature stages. Concentrations of total IgA, IgM and lactoferrin decreased significantly as time postpartum increased, whereas the IgG content showed no significant changes. The total IgA, IgM and lactoferrin levels were significantly decreased by all heat treatments (62.5°C for 30 min, 72°C for 15 s, 88°C for 5 s, and 100°C for 5 min). Heating at 62.5°C for 30 min did not affect the IgG content; however, the other heat treatments significantly reduced IgG concentration. At the times and temperatures selected for this study, the two lower temperature treatments were less detrimental to the protective factors than the higher temperature treatments.

Presence of biologically active amines in foods has been recognized for about 20 years. Past research on amines such as tyramine and histamine has not investigated factors which account for the variable concentrations often found in food products. This research was designed to investigate the roles of tyrosine and histidine decarboxylase activities and mono- and diamine oxidases (MAO and DAO) in amine formation and catabolism in cheese. The data indicate that the presence of decarboxylases is probably not the limiting factor for amine build-up. Most cheeses contained decarboxylase activities for both tyrosine and histidine; however, tyramine and histamine were present in some cheeses which did not contain detectable levels of the corresponding decarboxylases at the time of sampling. Few cheeses possessed MAO or DAO activities. When the oxidases were present, the amine contents were usually lower. A Colby cheese containing tyramine and histamine with high MAO activity also possessed high tyrosine decarboxylase activity. It appears that a major limiting factor in formation of biologically active amines in cheese is the availability of free amino acids for decarboxylation. Dairy-related bacteria generally lacked the amine oxidases. However, five of six dairy-related cultures with highly active decarboxylases showed MAO or DAO activities. The culture showing the highest DAO activity, Microbacterium lacticum , possessed low tyrosine and histidine decarboxylase activities.

Summary Commercially grown US Runner peanuts from 10 cultivars comprising 151 samples over two recent crop years contained 10.54 ± 1.50 mg α-tocopherol (T)/100 g kernel, 0.31 ± 0.12 β-T, 10.93 ± 2.04 γ-T and 0.76 ± 0.31 δ-T. Box plots revealed segregations in tocopherol levels for normal, mid and high oleic cultivars as well as production years among the cultivars. Correlation coefficients indicated positive relationships between β- and γ-T (r = 0.436, P

The trienzyme digestion including protease, α-amylase, and conjugase (γ-glutamyl hydrolase) for the extraction of total folate from cereal grain products used in AOAC Official Method 2004.05 was optimized using response surface methodology. Digestion times of α-amylase (p0.05) and conjugase (p0.01) showed significant effects on the response (total folate). Digestion time for Pronase digestion was not significant (p0.1). Ridge analysis showed that total times required for the trienzyme digestions ranged from 6.1 h for buckwheat to 8.7 h for CRM 121 (wholemeal flour). The predicted maximal value for CRM 121 (51 μg/100 g) was close to the certified value (50 ± 7 μg/100 g). The optimized extractions for the four cereals suggest that a generalized trienzyme extraction for cereals of 1, 2.5, and 6 h for Pronase, α-amylase, and conjugase, respectively, could be used to approximate total folate in cereals and cereal products. These conditions provide data comparable to AOAC Official Method 2004.05 for the cereals included in this study and would be suitable to approximate total folate in most cereals and cereal products. Compared to the official method, the shortened digestion provides cost savings and minimizes the folate loss possible with prolonged digestions.

The fatty acid profiles of commercially-grown Runner-type peanut cultivars (i.e., 10 cultivars, n = 151) collected over two production years (2005 and 2006) were determined by gas–liquid chromatography. Eight major fatty acids were identified in the sample set including palmitic (C16:0), stearic (C18:0), oleic (C18:1, ω9), linoleic (C18:2, ω6), arachidic (C20:0), gondoic (C20:1, ω9), behenic (C22:0), and lignoceric (C24:0) acids. Based on the oleic to linoleic acid (O/L) ratio, these cultivars were denoted as normal, mid-, and high-oleic peanut types. Correlation coefficients (r) between the eight major fatty acids identified were generated and revealed an inverse association between oleic and linoleic acids (r = –0.997, P

Though peanuts are classified as a high-fat food, they possess good proportions of fatty acids deemed as heart healthy. The fatty acid compositions of Runner peanuts were determined for commercially grown cultivars over two recent crop years. GC-FID analyses revealed that the fatty acid levels for Runner peanuts were significantly (p

Twelve popular ready-to-eat breakfast cereals fortified with folic acid were sampled in the United States in 2006, and the data have been incorporated into the USDA National Nutrient Database for Standard Reference. Cereals were collected from three statistically selected retail outlets in each of four primary census regions, and four composites of each product were prepared using random groupings of three locations each. Folic acid was determined using a validated LC-MS method, with 13C-folic acid as an internal standard, after trienzyme treatment and solid phase extraction. A cereal reference material (AACC VMA399) was analyzed as a control. Selected samples were also assayed using the standard microbiological method, with and without trienzyme extraction, to generate an estimate of endogenous folate. On average, as shown on the label, folate content was underestimated. In seven cereals, folate was within 5% of the declared value; in four cereals, it was 5–20% higher; and in two cereals, it was...

The relationship between vitamin E and the oxidative stability of raw and dry roasted peanuts was studied during storage at 21°C under air and vacuum. Lipid oxidation was monitored by peroxide values (PVs) and conjugated diene values (CDVs). In air, PV (meq/kg) for roasted peanuts reached 47 by 12 wk, whereas that for raw peanuts was below 2 after 38 wk. Under vacuum, lipid oxidation was significantly retarded (P < 0.05). Tocopherols of raw and roasted peanuts exponentially decreased with increasing PV. After 12 wk, about 50% of α-tocopherol (α-T) was lost for roasted peanuts under vacuum compared with about 90% under air. For raw peanuts, more than 70% of each tocopherol remained after 38 wk under air and vacuum. In general, α-T showed the least stability in roasted peanuts compared with other tocopherols under the reported storage conditions.

A method was developed to differentiate folic acid from total folate in enriched cereal products. By elimination of the protease and conjugase digestion steps from the trienzyme digestion used to measure total folate, folic acid can be directly quantified by the microbiological assay using Lactobacillus casei ( ssp. rhamnosus ) ATCC 7469. Determination of total folate by the trienzyme digestion together with assay of folic acid by the procedure reported here allows calculation of food folate and μg dietary folate equivalents (μg DFE). Recovery studies conducted at five concentration levels in a non-fortified wheat flour gave a mean recovery of 95.5 (RSD% 9.7) for folic acid and 98.5 (RSD% 5.0) for total folate. Recoveries from a variety of enriched cereal foods ranged from 88% to 99% for the folic acid extraction and 90% to 96% for the trienzyme digestion. Analysis of SRM 1846 Infant Formula ( n = 11 ) gave means± s.d. of 123.5±6.9 μg/100 g of folic acid and 136.6±6.7 μg/100 g of total folate (reference concentration value=129±28 μg/100 g). Intermediate precision determined as intra-laboratory reproducibility( r ) gave RSDr % values of 4.32 for the folic acid assay and 3.15 for the total folate assay. Microgram DFE values were determined for several enriched cereals by calculating food folate as the difference between total folate and folic acid and the formula μg DFE=μg food folate+(1.7×μg folic acid). The differential assay of folic acid and total folate is a simple and accurate procedure to determine μg DFE in enriched cereal-grains or foods containing enriched flour.

Tocopherol and tocotrienol contents of raw fruits and vegetables and processed products were determined by saponification and normal phase liquid chromatography. All samples were either locally obtained or collected as part of the US Department of Agriculture's National Food and Nutrient Analysis Program (NFNAP). All fruits, vegetables and processed products were selected from the USDA Key Foods list. The study included 32 raw and processed fruits, 22 raw vegetables, various tomato products, baked beans, cooked potatoes, frozen broccoli and frozen green peas. α-Tocopherol (α-T) was detectable in all products and usually represented the vitamin E form present in highest quantity. γ-Tocopherol (γ-T) was higher than α-T only in cantaloupes, figs, red raspberries, cauliflower, button mushrooms, lettuce, and green peas. α- and γ-Tocotrienols (α- and γ-T3) were measurable in several fruit and vegetables but at levels usually less than 0.1 mg/100 g.

A liquid chromatographic (LC) method was validated for the determination of total vitamin B6 in infant formula. Total vitamin B6 was quantified by converting the phosphorylated and free vitamers into pyridoxine. Pyridoxine was determined by ion pair reversed-phase LC with fluorescence detection. The method was subjected to an AOAC collaborative study involving a factory-manufactured, milk- and soy-based infant formula. Each was spiked at 3 concentrations in the range of 0–1 μg/g and sent as blind duplicate to participant laboratories. Nine laboratories returned valid data which were statistically analyzed for outliers and precision parameters. The repeatability relative standard deviation (RSDr) ranges were 2.0–4.0 and 3.5–5.9% for fortified milk- and soy-based formulas, respectively. The reproducibility relative standard deviation (RSDR) ranges were 8.2–8.4 and 6.7–11.2% for fortified milk- and soy-based formulas, respectively. HORRAT values ranged from 0.42 to 0.53, indicating that the precision of the method is acceptable. The mean RSDr:RSDR values were 0.60 and 0.55 for milk- and soy-based formulas, respectively. As expected, RSDs for the unfortified samples were higher, but their HORRAT values (0.81 and 2.06) helped define a realistic limit of quantitation as 0.05 μg/g. Recovery data were quantitative and varied between 81.4 and 98.0% (mean = 89.8%) for each of 6 spiked materials.

An interlaboratory-verified, liquid chromatographic (LC) method is presented for determination of all-racemic α-tocopheryl acetate and retinyl palmitate in infant formula. The extraction procedure uses matrix solid-phase dispersion. A sample is mixed with C18, and the mixture is packed into a reservoir and eluted with selective solvents to extract the analytes. After evaporation and filtration, the sample extract is injected directly into a normal-phase LC system with fluorescence detection. All-racemic α-tocopheryl acetate and retinyl palmitate are quantitated isocratically with a mobile phase of hexane containing isopropanol at 0.2% (v/v) and 0.125% (v/v), respectively. A nonfortified zero control reference material (ZRM) was spiked at 5 levels, with 5 replicate analyses of 1/2x, x, 2x, 4x, and 16x where “x” represents the minimum levels of 250 IU/100 kcal (vitamin A) and 0.7 IU/100 kcal (vitamin E) as specified in Title 21 of the Code of Federal Regulations, part 107.100. Recoveries of retinyl palmitate ranged from 83.8 to 107%, and those of all-racemic α-tocopheryl acetate ranged from 87.7 to 108%. Two additional laboratories analyzed the ZRM samples at 4 spiking levels with 6 replicates. Recoveries of retinyl palmitate and all-racemic α-tocopheryl acetate ranged from 92.2 to 104% and from 91.7 to 101%, respectively, in the second laboratory. Recoveries of retinyl palmitate and all-racemic α-tocopheryl acetate ranged from 85.3 to 97.0% and from 86.6 to 110%, respectively, in the third laboratory. Relative standard deviations for all 3 laboratories ranged from 0.2 to 7.5% with an average of 2.9%. In addition, each laboratory analyzed a commercial milk- and commercial soy-based infant formula. Excellent agreement in results was obtained between the 3 laboratories for vitamins A and E in all matrixes.

An interlaboratory verified, liquid chromatographic (LC) method is presented for the analysis of all-rac-α-tocopheryl acetate and retinyl palmitate in soy-based infant formula. The extraction procedure uses sample dehydration with magnesium sulfate followed by extraction with isopropanol, hexane–ethyl acetate (85 + 15, v/v). After evaporation and filtration, the sample extract is injected directly onto a normal-phase LC system with fluorescence detection. All-rac-α-tocopheryl acetate and retinyl palmitate are quantitated isocratically with a mobile phase of hexane containing 0.50% (v/v) and 0.125% (v/v) isopropanol, respectively. A zero control reference material (ZRM) was spiked at 5 levels, with 5 replicate analyses of 1/2x, x, 2x, 4x, and 16x where “x” is the minimum level of 250 IU/100 kcal (vitamin A) and 0.7 IU/100 kcal (vitamin E) as specified in 21 Code of Federal Regulations 107.100. The following recoveries and RSD values represent an average (n = 25) of the 5 levels for each analyte: all-rac-α-tocopheryl acetate, 100% (RSD = 3.5%); retinyl palmitate, 97.2% (RSD = 2.1%). Two additional laboratories analyzed the fortified ZRM samples. Average recoveries (n = 24) of all-rac-α-tocopheryl acetate and retinyl palmitate at 4 levels were all-rac-α-tocopheryl acetate, 99.0% (RSD = 4.0%), and retinyl palmitate, 96.2% (RSD = 1.4%) at the second laboratory. Average recoveries (n = 24) of all-rac-α-tocopheryl acetate and retinyl palmitate at 4 levels were all-rac-α-tocopheryl acetate, 102% (RSD = 1.4%) and retinyl palmitate, 95.7% (RSD = 2.0%) at the third laboratory. In addition, 6 replicates of the same commercial soy-based infant formula powder were run by the 3 laboratories.

The effect of peanut butter manufacture on vitamin E originating from raw peanuts (Arachis hypogaea L., runner-type) was determined. Tocopherols were quantified by normal-phase high-performance liquid chromatography. No significant differences were observed in tocopherol (T) values between 1998 and 1999 crop raw peanuts or between raw peanuts and peanut butter except for γ-T (P > 0.05). Oil and stabilizer added to the roasted peanuts during peanut butter processing provided 4% of α-T in the finished peanut butter. Retention of total tocopherols during peanut butter manufacture was 95%. Mean α-T values (mg/100 g) of commercial peanut products ranged from 12.3 (peanut oil) to 4.1 (dry roasted peanuts).

Textural properties of commercial peanut butter, commercial soy nut spread and three formulated peanut soy spreads with 8, 14, and 20% isolated soy protein were characterized using the Texture Analyser TA. TX2®. Significant differences were found between the textural parameters of the treatments (a = 0.05). Testing of color, aroma and textural attributes by a descriptive analysis panel indicated significant differences existed between the treatments. Based on consumer acceptability testing using a three-point acceptability scale, the three peanut soy spreads were acceptable products. A mathematical relationship (R 2 = 0.5) existed between the sensory descriptor aroma and consumer acceptability, and between superior quality (tastes great) and aroma and mouthcoating. No significant relationships were observed between instrumental and consumer acceptability testing.

Alpha-, beta-, gamma-, and delta-tocopherols (α-, β-, γ- and δ-T) were quantified in pecans (seedlings, Desirable, Stuart and Schley) of 2 crop year by using a direct extraction method coupled with normal-phase HPLC. % recoveries of the assay were about 98, 92, 97, and 97 for α-, β-, γ- and δ-T, respectively. Accuracy was excellent with low % CVs for all tocopherols. Overall precision was good except for δ-T, which was not resolved from an unidentified interference. There were significant differences in tocopherol contents among cultivars (p 0.05), but α-TE content of Desirable and seedling did vary (p < 0.05). γ-T was the predominant tocopherol for all pecan samples ranging from 20.1 to 29.3 mg/100 g. α-, β-, and δ-T occurred in low levels. Tocotrienols were not present. α-TE ranged from 3.3 to 4.2 in the different cultivars.

Fish- and peanut-containing half-products were obtained by extruding and drying tocopherol- and retinyl palmitate-fortified mixtures of tapioca starch and minced fish or partially defatted peanut flour (PDPF 60:40, wet basis). Half-products were puffed by deep-fat frying. Vitamins were determined simultaneously at each step of snack production using a direct solvent extraction method. Extrusion significantly reduced the content of tocopherols and retinyl palmitate in both products. Reduction of retinyl palmitate in fish and peanut extrudates during snack production was 48% and 27%, respectively. Final products contained more tocopherol than intermediates because of the high tocopherol content in the frying oil and its uptake.

Three experiments were conducted to test the hypothesis that extruding cottonseed meal (CSM) with supplemental lysine improves its feeding value by detoxifying gossypol. The performance of 1-wk-old straight-run Peterson x Arbor Acres broiler chicks fed diets containing 20% feed-grade or extruded CSM was compared with that of control chicks fed corn and soybean meal-based broiler rations. All diets were formulated to meet minimum NRC requirements. Lysine levels were adjusted by addition of synthetic lysine at rates of 0.5 to 2.0% of the protein in CSM. In all experiments, weight gain, feed intake, and feed conversion ratio (FCR) of broilers at 21 d were significantly affected by the diets. Feeding feed-grade and extruded CSM resulted in decreased body weight gain, increased feed intake, and inefficient feed utilization. When 2% lysine was added to feed-grade or extruded CSM, the body weight gains of chicks were not significantly different from those fed the control diet. The FCR of chicks fed feed-grade and extruded CSM plus 2% lysine at 21 d was significantly better than that of chicks fed feed-grade or extruded CSM alone. Abdominal fat pads (as a percentage of body weight) were significantly increased by the inclusion of CSM with or without the addition of lysine (P < or = 0.019). Liver, spleen, and heart weights were not affected by the presence of 20% CSM in the diet. The effects of CSM on plasma iron level was not consistent. Only in Experiment 1 did CSM cause a significant reduction in plasma iron. The hemoglobin contents and hematocrit values of blood from chicks fed diets with 20% CSM were not significantly different from those of the controls. The extrusion process reduced the free gossypol in CSM, but the total gossypol level was not changed, and chick performance was not improved. However, this study shows that, with adequate supplemental lysine, CSM can be used in broiler diets without a reduction in performance.

A simple, rapid procedure using direct solvent extraction and liquid chromatography was developed for the simultaneous determination and identification of α-tocopheryl acetate, β-carotene and tocopherols in reduced-fat mayonnaise. The method used a zero-control reference material (ZRM) (made in-house from olive oil and eggs) for accuracy determination. The vitamins and β-carotene were quantified by fluorescence and photodiode array detectors, respectively. The overall % recoveries (mean±S.D.)(n=5) for β-carotene, α-tocopheryl acetate, α-tocopherol, γ-tocopherol and δ-tocopherol were 101.4±1.4, 99.0±4.2, 102.0±3.6, 101.3±4.4 and 101.9±6.2, respectively. The method differentiates between natural and synthetic forms of vitamin E for accurate assessment of vitamin E biological activity. Comparative assays were performed using both direct solvent extraction and saponification.

A liquid chromatographic method is described for the determination of ergot alkaloids in wheat. Ergonovine, ergotamine, ergocornine, α-ergocryptine, and ergocristine are extracted from wheat with methanol–0.25% concentrated H3PO4 (40 + 60) pH 2.2, cleaned up by using a solid-phase extraction (SPE) disk, and separated by reversed-phase liquid chromatography with fluorescence detection. Ergot alkaloids are basic compounds that form water-soluble salts in acidic aqueous solution. Because ergot alkaloid salts are positively charged, they can be easily and selectively trapped on a negatively charged strong cation-exchange SPE disk. A strong wash solvent, methanol–0.25% concentrated H3PO4 (40 + 60) was used to remove matrix interferences not bonded by ionic interactions with the cation-exchange column. The ergot alkaloids were eluted from the ion-exchange column by adjusting the pH of the elution solvents to slightly basic conditions (pH 9). The SPE disk concentrated and cleanly separated the ergot alkaloids from matrix interferences. Standard calibration curves for ergot alkaloids for the concentration range 0.1–2.0 μg/mL were linear. The SPE disk had a column capacity equivalent to about 1 g extracted wheat. At spiking levels of 2.3–46 ng/g for ergonovine and 20–400 ng/g for ergotamine, ergocornine, α-ergocryptine, and ergocristine, the mean recovery was 88.1% with a coefficient of variation (CV) of 5.33%. The recovery data ranged from 79.1 to 95.9%. Ergonovine had the lowest overall recovery and the largest CV. The method has an estimated reliable limit of detection and limit of quantitation of

Rice fortified with Ultra RiceTM (UR) containing retinyl palmitate (RP) was tested as a potential vehicle for vitamin A delivery. After UR was mixed with a long grain rice at the ratio of 1 to 99 (w/w), the stability of RP in the rice mixture was studied during cooking and storage for 6 mo. After cooking, the percent retention range of RP was 75 to 87, depending upon the cooking methods. The stability of RP in the rice stored at 2 different temperatures and relative humidities (RH) appeared to be more affected by temperature than RH. Therefore, under tropical conditions, rice fortified with RP might require special handling to avoid significant RP losses.

A liquid chromatographic (LC) method is described for the determination of vitamin K1 in medical foods. The sample is enzymatically digested with lipase and α-amylase and extracted with 1% sodium bicarbonate solution–isopropanol (1 + 1). After C18 solid-phase extraction, vitamin K1 is separated by nonaqueous reversed-phase LC, converted to the hydroquinone by postcolumn zinc reduction, and quantitated by fluorescence detection. The limit of detection is 8 pg (3 σ), and the limit of quantitation is 27 pg (10 σ) on column. Linear response ranged from 0.1 to 1.0 ng vitamin K1 (r = 0.9999). The mean recovery (n = 38) for all spiking levels was 101.6 ± 2.85%. Analysis of Standard Reference Material 1846, Infant Formula, gave a mean value of 0.95 ± 0.088 mg vitamin K/kg (K or K1?)(n = 31) with a coefficient of variation of 9.26.

Extruded weaning foods were produced using cowpea + corn + soybean + soybean oil (35:50:10:5, w/w) and cowpea + corn + peanut (42:43:15, w/w) by twin screw extrusion and fortified with vitamin premix. A direct solvent extraction method was used to assay fortified α-tocopheryl acetate as the ester to differentiate it from the naturally occurring alcohol for accurate assessment of total vitamin E activity. The fortified retinyl palmitate was assayed from the same extraction and assayed as the more stable ester with the same LC conditions after changing the detection wavelengths. Using direct solvent extraction, analytical values of vitamin E homologs in extruded products were higher than those values from saponification.

A liquid chromatographic method for vitamin K1 in milk-based infant formula is described. The vitamins are extracted from infant formula by matrix solid-phase dispersion and quantitated by reversed-phase chromatography with fluorescence detection. Vitamin K1 is converted to the fluorescent hydroquinone with a postcolumn zinc reductive reactor. The limit of detection is 12 pg, and the limit of quantitation is 38 pg on-column. Linear responses were obtained in the range 0.55-22.1 ng/mL (r2 = 0.9998). Recoveries of vitamin K1 from an analyte-fortified blank material for milk-based infant formula averaged 91.7% (n = 25). The method provides a rapid, specific, and easily controlled assay for vitamin K1 in fortified infant formula.

Fatty acid methyl esters (FAMEs) of pure triglyceride standards, oils, and fat from dry matrixes were formed by transesterification using sodium methoxide in methanol–hexane. FAMEs were produced by direct addition of sodium methoxide¯hexane to samples and heating to simultaneously extract and transesterify acyl lipids. FAMEs were quantitated by capillary gas chromatography (GC) over a fatty acid concentration range of 0 to 1.7 mg/mL (r ≥ 0.9997). Total fat was calculated as the sum of individual fatty acids expressed as triglyceride equivalents, in accordance with nutrition labeling guidelines. Saturated, polyunsaturated, and monounsaturated fats were calculated as sums of individual free fatty acids. Absolute recoveries determined from individual fatty acids in test samples ranged from 69.7 to 106%. Recoveries (relative to the C13:0 internal standard) for individual fatty acids in test samples ranged from 95 to 106%. Reproducibility was constant at each fatty acid level in the reaction mixture (n = 5, coefficient of variation [CV]

A liquid chromatographic method is described for analysis of all-rac-α-tocopheryl acetate and retinyl palmitate in medical food. The vitamins are extracted in isopropyl alcohol and hexane-ethyl acetate without saponification and quantitated by normal-phase chromatography with fluorescence detection. All-rac-α-tocopheryl acetate and retinyl palmitate are chromatographed isocratically with a mobile phase of 0.5% (v/v) and 0.125% (v/v) isopropyl alcohol in hexane, respectively. Recovery studies performed on a medical food zero control reference material (ZRM) fortified with the analytes averaged 99.7% (n = 25) for retinyl palmitate and 101% (n = 25) for all-rac-α-tocopheryl acetate. Coefficients of variation were 0.87-2.63% for retinyl palmitate and 1.42-3.20% for all-rac-α-tocopheryl acetate. The method provides a rapid, specific, and easily controlled assay for analysis of vitamin A and vitamin E in medical foods. Use of chlorinated solvents is avoided.

Retinyl acetate in soy based infant formula was extracted by matrix solid phase dispersion (MSPD) and chromatographed by isocratic normal phase chromatography on a Si 60 column with a mobile phase of 0.28% (v/v) isopropanol in hexane. Detection was by fluorescence (Ex λ=325, Em λ=470). Fluorescence response was linear (r2=0.999) from 0.10 – 2.5 μg/mL. Recoveries determined on a soy based infant formula zero control reference material (ZRM) containing added analyte at five levels averaged 94.7% (n=25) with CV's from 0.57–3.53%. The method expands the use of MSPD extraction to the analysis of retinylacetate in soy based infant formulas.

A liquid chromatographic method is described for analysis of all-rac-α-tocopheryl acetate and retinyl palmitate in medical food. The vitamins are extracted from medical food without saponification by matrix solid-phase dispersion and chromatographed by normal-phase chromatography with fluorescence detection. Retinyl palmitate and all-rac-α-tocopheryl acetate are quantitated isocratically with a mobile phase of 0.125% (v/v) and 0.5% (v/v) isopropyl alcohol in hexane, respectively. Results compared favorably with label declarations on retail medical foods. Recoveries determined on an analyte-fortified zero reference material for a milk-based medical food averaged 98.3% (n = 25) for retinyl palmitate spikes and 95.7% (n = 25) for all-rac-α-tocopheryl acetate spikes. Five concentrations were examined for each analyte, and results were linear (r2 = 0.995 for retinyl palmitate and 0.9998 for all-rac-α-tocopheryl acetate) over the concentration range examined, with coefficients of variation in the range 0.81-4.22%. The method provides a rapid, specific, and easily controlled assay for analysis of retinyl palmitate and all-rac-α-toco-pheryl acetate in fortified medical foods.

A liquid chromatographic method is described for the analysis of all-rac-α-tocopheryl acetate and retinyl palmitate in soy based infant formula. The vitamins are extracted from infant formula without saponification by matrix solid phase dispersion (MSPD) and quantitated by normal phase chromatography with fluorescence detection. Retinyl palmitate and all-rac-α-tocopheryl acetate are quantitated isocratically with a mobile phase of hexane containing isopropanol @ 0.125% (v/v) and 0.5% (v/v), respectively. Results compared favorably to the label declaration on a retail infant formula product.

Direct solvent extraction with hexane:ethyl acetate (90:10, v/v), saponification, and Soxhlet extraction with hexane were evaluated for their usefulness as extraction methods to determine vitamin E in peanuts and peanut butters. The direct solvent extraction procedure yielded higher values for each tocopherol homolog in peanut and peanut butter compared to the other methods. Coupling of the rapid, direct solvent extraction with normal phase chromatography on Si 60 provides a highly reproducible procedure to quantitate vitamin E in peanuts and peanut products. The overall % recoveries (means ± S.D.) of this study for α-, β-, γ-, and δ-tocopherol were 99.9 ± 3.29, 100.4 ± 11.7, 98.9 ± 5.94, and 100.3 ± 4.87, respectively. Limits of detection and limits of quantitation were 0.21, 0.06, 0.11, and 0.08 ng and 0.39, 0.14, 0.23, and 0.13 ng, respectively, for α-, β-, γ-, and δ-tocopherol. Repeatability, reproducibility, and accuracy of the methods were excellent with % CVs for accuracy of 1.19 (α-T), 1.55 (γ-T), and 2.69 (δ-T). Accuracy was not acceptable for β-T due to its extremely low concentration in the peanut and because peak purity was not obtained for β-T. The method was applied to other seeds with good success. Major homologs were γ-T in peanuts, pecans, cashews, walnuts, and pistachio; α-T in almonds; and α-T3 in macadamia.

A liquid chromatographic method is described for analysis of all-rac-α-tocopheryl acetate, tocopherols, and retinyl palmitate in soy-based infant formula. The vitamins are extracted in isopropyl alcohol and hexane-ethyl acetate without saponification and quantitated by normal-phase chromatography with fluorescence detection. All-rac-α-tocopheryl acetate and retinyl palmitate are quantitated isocratically with mobile phases of 0.5% (v/v) and 0.125% (v/v) isopropyl alcohol in hexane, respectively. Recoveries from zero control reference material soy-based formula averaged 97.2% (n = 25) for retinyl palmitate and 100% (n = 25) for all-rac-α-tocopheryl acetate. Coefficients of variation ranged from 1.21 to 2.86% for retinyl palmitate and from 1.49 to 5.16% for all-rac-α-tocopheryl acetate. The method provides a rapid, specific, and easily controlled assay for analysis of vitamin A and vitamin E in fortified infant formula. Additionally, the method eliminates use of chlorinated solvents.

A liquid chromatographic method is described for the analysis of vitamin E in margarine and vegetable oil products (spreads). The tocopherol homologs (α, γ, δ-tocopherol) are extracted in hexane with anhydrous MgSO4 added to remove water. Complete resolution of the homologs is achieved on a normal phase column and a mobile phase of 0.9% isopropanol in hexane with fluorescence detection. Based on five repetitive assays the mean recoveries were 99.0±1.4, 97.4±2.2%, and 99.5±2.6% for α-, γ-, and δ-tocopherol, respectively. The method is rapid, specific, and accurate for the measurement of vitamin E in margarine and vegetable oil spreads. Further, the method avoids: (1) saponification techniques (2) emulsion forming organic solvent extractions and (3) the use of chlorinated solvents. The limit of detection for α-, γ-, and δ- tocopherol were 23.2, 2.96, and 1.98 μg/100g, respectively. The limit of quantitation for α-, γ, and δ- tocopherol were 39.8, 5.00, and 3.02 μg/100g, respectively. The vitamin E ...

A zero control reference material (ZRM) for milk and soy-based infant formula was manufactured and characterized. The ZRM was free of retinyl palmitate and all-rac-α-tocopheryl acetate. The composition was similar to commercially available infant formula. The ZRM provides a valuable tool to ascertain method performance.

Proximate and micronutrient composition of cantaloupe and honeydew melons purchased from six marketing locations at marketing times near maximum and minimum product availability were determined. Cantaloupe varieties purchased at periods near maximum availability showed significantly higher (α= 0.01) levels of niacin, riboflavin, thiamin, ascorbic acid, folacin and Cr compared to those purchased near minimum availability. Honeydew melon varieties purchased at periods near maximum availability showed significantly lower (α= 0.01) levels of ascorbic acid, folacin, pantothenic acid, K, Zn, and Cr compared to those purchased near minimum availability. Although some differences were observed between values obtained and those reported in Handbook 8–9, proximate composition and mean values for micronutrients approximated those previously reported.

Three optimized weaning foods containing 23-39% wheat flour, 19-35% cowpea flour, 15-22% sesame flour or sesame seeds, 5-15% nonfat dry milk (NFDM), 0-7.9% cottonseed oil, and 5% sucrose were developed for application in Egypt using Brill Feed Formulation software. Blends of all components except NFDM and sucrose were processed in an InstaPro Model 600 extruder at 140C and residence time of approximately 30 s. Essential amino acid content of all formulas exceeded the specified minimum and the requirements of the 6-month child. PER values ranged from 2.18 to 2.57, relative NPRs were 87-101% that of casein and true digestibilities were 86-89%. Trypsin inhibitor activity was reduced by 82-100% by extrusion.

A liquid chromatographic method is described for the concurrent analysis of sucrose polyester (SPE), vitamin A and β-carotene in margarine. The SPE and vitamins are separated from the acylglycerol by gel permeation chromatography (GPC). The GPC system is equipped with a refractive index and ultraviolet (UV) detector (313 nm) to monitor the peak elution. Following collection, the vitamins and SPE are analyzed by C-18 reverse phase chromatography. A ternary gradient of acetonitrile, methylene chloride and isopropanol with evaporative light scattering detection is used for SPE analysis. Vitamin A and s-carotene are quantitated after isocratic elution with acetonitrile/methylene chloride/methanol (700/300/2, v/v/v) as mobile phase and detection at 313 nm and 436 nm, respectively. Well resolved, interference free chromatograms were obtained for each analyte.

Two experiments were conducted to determine the effects of dietary supplemental folic acid and methionine on the performance of starting broiler chicks for 18 d. Four levels of dietary folic acid (.24, .54, 1.14, and 2.34 mg/kg) and four levels of dietary methionine (.45, .53, .61, and .69%) were fed in a factorial design. There were three replicates of eight chicks each per each treatment. The basal diet was based on corn, isolated soybean protein, meat and bone meal, and fish meal. It contained adequate amounts of all nutrients except methionine and folic acid. Increased growth was observed in chicks fed the basal diet supplemented with either folic acid or methionine. Total dietary folic acid and methionine plus cysteine requirements for maximum growth were estimated to be 1.80 mg/kg and .85% in Experiment 1 and 1.47 mg/kg and .87% in Experiment 2, respectively. There were interactions between dietary folic acid and methionine on weight gain in both experiments. Chicks fed the diet containing 2.34 mg folic acid/kg tended to have depressed growth, as in previous experiments. There was a significant linear feed conversion response to folic acid in Experiment 1 and to methionine in Experiment 2. There were both linear and quadratic liver folic acid responses to dietary folic acid in both experiments. There was no indication that dietary methionine had any effect on liver folic acid content. No differences in bone ash, hemoglobin, hematocrit, or incidence of tibial dyschondroplasia were detected due to methionine or folic acid supplementation.

A liquid chromatographic (LC) method is described for analysis of sucrose polyester (SPE) in salad dressings. SPE is separated from acylglycerols by gel permeation chromatography. The elution time window for SPE was determined with an evaporative light-scattering mass detector. The SPE fraction is collected and quantitated by C18 reversed-phase chromatography with a ternary gradient. The gradient consists initially of 45.5% methylene chloride, 52.5% acetonitrile, and 2.0% isopropyl alcohol. After 5 min, the ratios change to 98.0% methylene chloride and 2.0% isopropyl alcohol and remain unchanged for the next 6 min. The gradient then reverts back to initial conditions and is ready for another injection after a total run time of 17 min. Sucrose octaacetate was used as an internal standard to simplify quantitation. The mean (n = 3) recovery of SPE was 92.4 ± 2.6%. Reversed-phase LC precision was determined by performing 6 replicate analyses of Italian dressing. The mean recovery ± standard deviation and coefficient of variation were 261 ± 9.5 mg SPE/g and 3.6%, respectively.

Low cost protein/energy rich weaning foods suitable as supplements to human milk that satisfy the nutritional requirements for 6-12 month infants were designed for the Egyptian market. Three formulas were optimized with Brill Formulation Software using FAO/WHO weaning food recommendations. Selected least cost formulations included: Formula #1: 38.5% wheat flour, 19.4% cowpea flour, 14.8% sesame flour, 15% NFDM, 7.3% cottonseed oil and 5% sucrose; Formula #2: 23.3% wheat flour, 35.1% cowpea flour, 21.6% sesame seeds, 15% NFDM and 5% sucrose; Formula #3: 29.9% wheat flour, 35% cowpea flour, 16.6% sesame flour, 5.25% NFDM, 7.9% cotton seed oil and 5% sucrose. Each formula contained about 20% protein, 400 Kcal/100 g and sufficient amounts of essential amino acids. The extrusion process did not affect the nutrient composition of the weaning food formulas.

Microbiological assays were conducted to determine the level of total folate in feed ingredients using Lactobacillus casei (ATCC 7469). Fifty-seven samples of feedstuffs were collected from several locations in the southeastern USA by a major broiler producer. Folic acid contents of samples pretreated before assay with three enzymes (conjugase, α-amylase, a mixture of protease (Pronase®, were 22±86 ± 1.99 (μg per 100 g ± SD) for corn (N = 14), 22±01 + 1.18 for fish meal (N = 7), 29.34 ± 0.55 for milo (N = 4), 25.80 ± 6.93 for bakery meal (N = 5), 56.76 ± 4.97 for meat and bone meal (N = 4), 85.14 ± 2.56 for wheat middlings (N = 5), and 193.97 ± 11.19 for soybean meal (N = 18). Predigestion with conjugase, α-amylase and Pronase® liberated folic acid and increased values by 22.3% compared to conjugase predigestion alone (P≤0.05). This study shows that the traditional conjugase pretreatment does not completely free folate from complex feed ingredients for microbiological analysis.

Uncharacteristic of most whole foods, the major component of tree nuts is lipid; surprisingly, information on the lipid constituents in tree nuts has been sporadic and, for the most part, not well reported. Most published papers focus on only one nut type, or those that report a cultivar lack a quality control program, thus making data comparisons difficult. The present study was designed to quantify the healthful lipid constituents of 10 different types of commercially important tree nuts (i.e., almonds, black walnuts, Brazil nuts, cashews, English walnuts, hazelnuts, macadamias, pecans, pine nuts, and pistachios) according to standardized, validated methods. The total lipid content of each nut type ranged from 44.4 ± 1.9% for cashews to 77.1 ± 1.7% for macadamias. As expected, the major fatty acids present in the tree nuts were unsaturated: oleic (18:1 ω9) and linoleic (18:2 ω6) acids. A majority of the lipid extracts contained

A reversed-phase ion pair liquid chromatographic method developed for the simultaneous determination of thiamine (B1), riboflavin (B2), and pyridoxine (B6) in perchloric acid extracts of infant formulas was modified to include medical foods. UV detection of B1 and B2 was replaced by fluorescence detection, which resulted in improved sensitivity and specificity. B1 was detected by fluorescence after conversion to thiochrome by a postcolumn reaction with sodium hydroxide and potassium ferricyanide. The method uses a mobile phase of water, acetonitrile, hexanesulfonic acid sodium salt, ammonium hydroxide, and phosphoric acid adjusted to pH 3.6. The column is a 300 × 3.9 mm Nova Pak C18. Limits of detection were 0.05 μg/mL for B1 and B2 and 0.01 μg/mL for B6 by fluorescence detection. The system reproducibility was evaluated by completing 10 repetitive determinations on a medical food that gave a coefficient of variation of 5.9, 6.0, and 10.7% for B1, B2, and B6, respectively. Mean recoveries (n = 10) were 111,96.3, and 113% for B1, B2, and B6, respectively. The results compared favorably with those by AOAC Official Methods 942.23, 940.33, and 961.15 for B1, B2, and B6, respectively.