Mineral contents of Nigerian grains and baby foods

Maize (Zea mays), sorghum (Sorghum vulgare), cowpea (Vigna unguiculata Walp) and soya beans (Glycine max) are available locally in Nigeria. Their suitability for use in the preparation of baby foods was assessed by comparing their content of a range of minerals with that of a number of imported baby foods. The iron content of the baby foods ranged between 57 and 82 μg g^?1, which was similar to the range in the foodstuffs, 49 to 201 μg g^?1. Calcium, however, was much lower in the foodstuffs, 22-1300 compared with the baby foods, 4100-8600 μg g^?1.     

The proximate composition and some minor constituents of poppy seeds

The proximate chemical composition of poppy seeds, along with minerals and water-soluble vitamins content was investigated. The compositions of the fatty acids and tocopherols of the extracted oil were also determined. The proximate analysis of poppy seeds showed the following composition: (440 g kg^?1), protein (211 g kg^?1), moisture (50 g kg^?1), ash (63 g kg^?1), crude fine (62 g kg^?1) and total carbohydrates (236 g kg^?1). Potassium and calcium were the predominant elements in the poppy seeds. Linoleic acid was the major unsaturated fatty acid (750 g kg^?1 total fatty acids) while palmitic acid was the main saturated one (86-4 g kg^?1). The amounts of α-, β- and δ-tocopherols found in poppy seed oil were 220 μg g^?1, 40 μg g^?1 and 20 μg g^?1 respectively. Among the water-soluble vitamins determined, pantothenic acid was found at the highest level followed by niacin and thiamin.     

高压液相色谱法同时测定食品中的维生素A、D、E和K

本方法研究了应用反相高压液相色谱技术,同时测定食品中的维生素A、D、E、K。以C18柱为固定相(μ Bondapak C18,30cm×4mm),甲醇作流动相。在290nm下测定维生素A、E,在265nm下测定维生素D、K。样品的前处理分为两种,第一种皂化法,可同时测定维生素A、D、E。加标样品的回收率分别为:V_A97.2～110％,V_D92.3～102％,V_E96.6～110％。变异系数(CV％)分别为V_A2.29～3.15％,VD5.99～8.63％,V_E3.60～4.16％。第二种为酶解法,可同时测定维生素A、D、E、K四种,加标样品的回收率分别为:V_A87.62～98.01％,V_D90.23～102.7％,V_E86.18～91.09％,V_K80.15～85.07％。变异系数(CV％)分别为:V_A5.51％,V_D8.87％,V_E4.91％,V_K3.67％。     

Method of simultaneous analysis of vitamins A, E and beta-carotene in dairy products

A method has been suggested for simultaneous assay of vitamins A, E and beta-carotene in milk products. A specimen sample is subjected to alkaline hydrolysis, then vitamins are extracted and separated in the column with aluminium oxide; for beta-carotene elution hexane is used, for vitamin E - acetone-hexane (10:90), for vitamin A - acetone-hexane (15:85). beta-carotene is assayed in hexane by absorption. Vitamin A and E fractions are evaporated, the residue is diluted in absolute alcohol, vitamin A is identified by absorption, vitamin E - by the colour Emmery-Engel reaction. The variation coefficient in the assay of vitamins A, E and beta-carotene was less than 10% in 5 out of 6 cases.     

Protection against the toxic effects of the favism factor (divicine) in rats by vitamins E,A and C and iron chelating agents

Five experiments were carried out with weanling Sprague-Dawley rats to determine if prior administration of either free-radical scavenging compounds (vitamins A, C and E) or chelating agents (EDTA and desferox- amine) affected the toxicity of divicine (DV). In all experiments, intraperitoneal (IP) injections of 250 mg g^?1 body weight of DV alone resulted in 100% mortalities within 24 h with most of the deaths occurring before 4 h. Death was accompanied by a rapid decrease in the concentration of glutathione (GSH) in the red blood cells (RBC) and the 576 nm/628 nm absorbance ratio of haemoglobin. The first experiment demonstrated that IP injections of different amounts of vitamin E, 1 h prior to DV injection, prevented the decrease in the haemoglobin absorbancy ratio and GSH concentration and greatly reduced mortalities. In rats that received 1000 IU of vitamin E kg^?1 body weight prior to DV injection, mortality was only 20%. The second experiment demonstrated that the optimal time for IP administration of vitamin E was 1 to 4 h prior to DV injection although some protection was obtained after 96 h. In contrast, the optimal time for intramuscular injections was 24 h prior to DV administration. A dosage of 250 or 500 IU of vitamin E kg^?1 body weight provided complete protection (zero mortalities) against the toxic effects of DV. In the third experiment, the addition of varying amounts of vitamin E to the diet resulted in a dose dependent mortality curve with no deaths occurring in rats fed diets containing the highest concentrations of vitamin E. The fourth experiment also demonstrated that vitamin A, vitamin C, EDTA and desferoxamine each protected rats to varying degrees against the toxic effets of DV. In the final experiment it appeared that the combined injections of a free-radical scavenging compound (vitamin E) and a metal chelator (desferoxamine) provide more protection than vitamin E alone. These results demonstrate for the first time in vivo that certain vitamins, especially vitamin E, and metal chelators can provide varying and in some cases 100% protection against the toxic effects DV.     

Compositional variation in β‐carotene content,carbohydrate and antioxidant enzymes in selected banana cultivars

Banana is one of the most important tropical fruits, and India ranks first in its world production. Banana cultivars rich in provitamin A carotenoids may offer a potential food source for alleviating vitamin A deficiency, particularly in developing countries. With a view to exploit banana peels as a source of valuable components, in the present study, proximate composition, carotenoids, beta‐carotene and some anti‐oxidative enzymes as well as carbohydrate content of selected Indian banana varieties were determined. Karpooravalli cultivar of banana showed the maximum accumulation of carotenoid content in the non‐edible (68 μg g^?1 d.w.) portion of banana, while being the second highest in beta‐carotene content (143.12 μg per 100 g). However, Red Banana ranked highest in total carotenoid contents for pulp (4 μg g^?1 d.w.) and beta‐carotene was estimated to be the highest in the case of peels (241.91 μg per 100 g) and in pulp (117.2 μg per 100 g). Karpooravalli cultivar of banana is also rich in carbohydrate content in terms of total starch (1786.0 μg g^?1 d.w. in peels and 544.85 μg g^?1 d.w. in pulp) and sugars (53.53 μg g^?1 d.w. in peels and 39.05 μg g^?1 d.w. in pulp). The catalase enzyme activity in these peels ranged from 5.66 to 35.57 nmol min^?1 mg^?1 proteins and was found at a higher level in cultivar Poovan, while the ascorbate peroxidase showed the range of 2.25 to 6.22 μmol min^?1 mg^?1 proteins. The peels of cultivars Red Banana and Karpooravalli are rich source of bioactive compounds, such as carotenoids (beta‐carotene), anti‐oxidative enzymes and carbohydrate contents.     

NovaSil clay does not affect the concentrations of vitamins A and E and nutrient minerals in serum samples from Ghanaians at high risk for aflatoxicosis

To assess the potential interference of NovaSil (NS) clay with micronutrients in humans, vitamins A and E and minerals (15 nutrient and 15 non-nutrient minerals) were measured in serum samples from a 3-month intervention trial with NS. Participants (n?=?177) were randomly divided into three groups that received 3.0 g NS day^?1 (high dose, HD), 1.5 g NS day^?1 (low dose, LD), or placebo (PL). Levels of vitamins A and E in serum were comparable among the three study groups at baseline, 1 month and 3 months of NS intervention. Gender-stratified non-parametric mixed-effect model analysis showed no significant effects of dose and dose–time interaction for levels of vitamins A and E. A significant time effect was detected; however, it was limited to an increase in vitamin E in the male participants over the course of the study. No significant differences were found in levels of the nutrient and non-nutrient minerals between the HD and PL groups at baseline and 3 months of NS intervention, except for strontium levels. Strontium was significantly increased (p?<?0.001) in the HD group (male?=?113.65?±?28.00 µg l^?1; female?=?116.40?±?24.26 µg l^?1) compared with the PL group (male?=?83.55?±?39.90 µg l^?1; female?=?90.47?±?25.68 µg l^?1) following the 3-month intervention with NS. These results, combined with safety and efficacy data, confirm that NS clay is highly effective in reducing aflatoxin exposure and acts as a selective enterosorbent that does not affect the serum concentrations of important vitamins and nutrient minerals in humans.     

Preparation of quality control materials for the determination of sulfonamides in animal feed

A feasibility study of the preparation of quality control materials for the analysis of medicated feeds has been carried out. Two analytical methodologies for the analysis of sulfonamides in feeds were developed, validated and applied to homogeneity and stability studies. Pig feeds spiked with sulfadiazine and sulfadimidine were prepared. The drugs were spiked at 500 µg g^?1, representing what can be expected in a commercial medicated feed, and at 2 and 5 µg g^?1, which roughly correspond to drug-free feeds cross-contaminated during the fabrication process. The homogeneity of both the bulk and the bottled materials was verified. A stability study of the materials containing 2 and 5 µg g^?1 of sulfonamides was carried out over an 18-month period at room temperature, at 4°C and ?20°C. The determination of sulfadiazine and sulfadimidine in samples coming from these homogeneity and stability studies of the quality control materials was carried out by high-performance liquid chromatography (HPLC) with either ultraviolet light or fluorimetric detection, depending on the concentration of the analytes in the samples.     

Characterisation and variation of antioxidant micronutrients in lettuce (Lactuca sativa folium)

The main phenolic compound in six studied lettuce cultivars (five green and one red) was identified as dicaffeoyl tartaric acid. Quantitative but not qualitative differences were found in the phenolic profiles among green cultivars. The red oak leaf cultivar contained twofold more dicaffeoyl tartaric acid and 10‐fold more chlorogenic acid than the green cultivars. Total phenolics ranged from 8.4 to 12.9 mg g^?1 dry weight in green varieties and reached 27.8 mg g^?1 dry weight in red oak leaf. Carotenoids and vitamins E and C were also quantified. Lutein was the main carotenoid found in all cultivars, together with another xanthophyll. The period of harvesting had only a marginal influence on total phenolic levels, whereas carotenoid and vitamin E levels were higher at the second period of harvesting. Vitamin C levels ranged between 6.1 and 9.9 mg per 100 g fresh weight. We investigated the total antioxidant power in lettuce. Total phenolics accounted for more than 60% of the total antioxidant capacity. Dicaffeoyl tartaric acid accounted for 55%. Copyright © 2004 Society of Chemical Industry     

UPLC-ESI-MS/MS for determining trans- and cis-vitamin K1 in infant formulas: method and applications

A simple and sensitive method of determining vitamin K₁ isomers (cis-and trans-forms) was developed for routine monitoring of supplemented infant formulas. The proposed method involves the applications of the lipase hydrolysis and the liquid-to-liquid extraction. After the hydrolysis and extraction procedures, the vitamin K₁-enriched extract was directly injected into the ultra-performance liquid chromatography–tandem mass spectrometry system (UPLC-MS/MS). The components were detected using electrospray ionization (ESI) in positive-ion and quantified by multiple-reaction monitoring (MRM) mode. trans-vitamin K₁ was separated from the biologically inactive cis-isomer through a C₃₀ column (4.6?×?150?mm, 3?μm), and vitamin K₁-d₇ was used as an internal standard. Calibration curves were linear over the range of 9.3–464.75?ng?ml^?1 for trans-vitamin K₁ (r ²?>?0.999) and 1.71–85.25?ng?ml^?1 for cis-vitamin K₁ (r ²?>?0.999). The limit of detection for trans- and cis-vitamin K₁ was 0.011?μg 100?g^?1 and 0.01?μg 100?g^?1. The limit of quantification was 0.037?μg 100?g^?1 and 0.031?μg 100?g^?1, respectively. The intra- and inter-batch variations (RSD%) were less than 5?%. The proposed method was applied to determine vitamin K₁ isomers in milk-based, soy-based and rice-based infant formulas, and the cis-vitamin K₁ isomer contributes to 7.05–17.21?% of the total vitamin K₁ in certain infant formulas.     

柱切换法液相色谱测定保健食品中的VA、VD、VE

建立柱切换法液相色谱测定保健食品中VA、VD、VE含量的方法.参照GB 5009.82-2016《食品中维生素A、D、E的测定》样品前处理方法,以Agilent Poroshell 120 PFP(4.6 mm×100 mm,2.7 μm)为一维色谱柱,甲醇、水为流动相梯度洗脱,分离VA和VE的4种异构体,以Agile...     

Simultaneous determination of 2,4,6-trichloroanisole, 2,3,4,6-tetrachloroanisole and pentachloroanisole in foods and packaging materials by high-resolution gas chromatography-multiple ion monitoring-mass spectrometry

A method has been developed for the determination of 2,4,6-trichloroanisole, 2,3,4,6-tetrachloroanisole and pentachloroanisole in foods and packaging materials. Using combined high-resolution gas chromatography-multiple ion monitoring-mass spectrometry, and with the addition of 3,5-dimethyl-2,4,6-trichloroanisole as an internal standard, a series of calibration curves were prepared covering the concentration range 0.1 to 100 μg kg^?1. The detection limit, with quantitation by extrapolation only, was 0.01 μg kg^?1. The mean extraction efficiency of the combined distillation-extraction step was greater than 90% for each of the chloroanisoles analysed. The mean extraction efficiency for the internal standard was 105%. The reproducibility of the results obtained in the gas chromatography-mass spectrometry step was assessed and the coefficients of variation lay in the range from 2 to 11%.     

Biogenic amines profile and concentration in commercial milks for infants and young children

Commercial milks for infants and young children (CMIYC) received much attention during last years for their impact on the nutritional status, health and development of the new-born and babies. Among possible contaminants contained in these foods, biogenic amines (BAs) have rarely been determined although they can exert toxic effects in humans if ingested at high concentrations. Spermine, spermidine, putrescine, histamine, tyramine, β-phenylethylamine and cadaverine have been quantified in CMIYC samples by LC-UV after derivatisation with dansyl-chloride. Once optimised in terms of linearity (R² ≥ 0.989), recovery percentages (92.9–97.3), LOD (0.2–0.4 μg g^?1 or 0.03–0.05 μg mL^?1 depending on the samples), LOQ (0.5–1.0 μg g^?1 and 0.08–0.13 μg mL^?1 depending on the samples) and repeatability (0.1–0.2 intra-day; 0.2–0.4 inter-day), the method has been applied to real samples. Very low total BAs concentrations have been found in reconstituted (1.18–3.12 mg L^?1) and liquid milks (0.33–2.30 mg L^?1), with different biogenic amine profiles and distributions. A risk assessment based on the available information regarding Acute Reference Doses of histamine and tyramine, as well as the application of common Biogenic Amine Indexes, showed that none of the analysed samples represented a possible risk for babies, also considering a worst case evaluation. These findings confirmed the strict safety and quality protocols adopted during the production of CMIYC.

Chemical compounds studied in this article: Ammonium chloride (PubChem CID: 25517); Cadaverine hydrochloride (PubChem CID: 5351467); Hydrochloridric acid (PubChem CID: 313); Histamine dihydrochloride (PubChem CID: 5818); Phenylethylamine hydrochloride (PubChem CID: 9075); Putrescine dihydrochloride (PubChem CID: 9532); Sodium hydroxide (PubChem CID: 14798); Spermine tetrahydrochloride (PubChem CID: 1103); Spermidine trihydrochloride (PubChem CID: 1102); Tyramine hydrochloride (PubChem CID: 66449).     

Determination of bisphenol A in canned fatty foods by coacervative microextraction,liquid chromatography and fluorimetry

Decanoic acid reverse micelle-based coacervates were used to provide simple, rapid and almost solventless extraction of bisphenol A (BPA) from canned fatty foods. The procedure involved the extraction of 200–400 mg of homogenised food sample with an aqueous solution containing 20% THF and 200 mg of decanoic acid, conditions under which the coacervate (around 550 µl) formed in situ and instantaneously. The overall sample treatment took about 30 min and several samples could be simultaneously treated using conventional laboratory equipment. No clean-up or solvent evaporation were required before determination of BPA by liquid chromatography and fluorescence detection. Recoveries in samples were between 90 and 99%, with relative standard deviations in the range 2–7%. The limit of quantification ranged 29–15 ng g^?1 for 200–400 mg of sample, being far below the current specific migration limit (SML) set by the European Commission (600 ng g^?1). The method was successfully applied to the determination of BPA in the solid content of canned fish (from 20 to 129 ng g^?1) and meat (from undetected to 37 ng g^?1).     

Development of methods for the determination of vitamins A, E and β-carotene in processed foods based on supercritical fluid extraction: a collaborative study

New methodologies based on supercritical fluid extraction (SFE) have been developed for the determination of fat-soluble vitamins in processed foods. The results obtained so far indicate that SFE is well suited to extraction of fat-soluble vitamins from food products, although validation work is required to establish accuracy and precision. The vitamins investigated were A, E and β-carotene, and the processed foods were UHT milk, milk powder, minced meat, liver paste, infant formula, canned baby food and margarine. Extraction equipment employed analyte collection on either a solid-phase trap or in a solvent. After extraction, the samples were saponified and the vitamins determined using reversed-phase liquid chromatography with ultraviolet or fluorescence detection. Sample throughput was at least 12 samples day -1 , i.e. at least twice the number achievable with a conventional extraction methodology. The detection limits for the vitamins in different processed foods were well below 0.1 µg g -1 . Recoveries (in comparison with vitamin levels obtained using conventional solvent extraction) were close to 100% for experienced personal with access to modern automatic equipment. To reach this level, it was necessary to protect the vitamins with an antioxidant during the different steps of the analysis procedure, to add methanol or ethanol to the extraction cell to facilitate the analyte extraction from the food matrix, and when using a solid-phase trap, to employ a fractionated extraction-elution procedure to prevent breakthrough losses. The developed methods were tested in a validation exercise between five laboratories, which had taken part in the method development, and in an intercomparison between 10 laboratories including laboratories with less experience of vitamin determination. The within-laboratory RSD was generally ≤11%. The average of the between-laboratory relative standard deviation (RSD) was about 23% in the validation, and increased to about 40% in the intercomparison. Ruggedness tests performed at different steps of the project showed that different types and models of equipment did not give large differences in recoveries. Thus, the increasing RSD can largely be ascribed to differences in experience in vitamin analysis of the participants.     

在线固相萃取-二维液相色谱法同时测定儿童配方奶粉中维生素A、D、E

建立在线固相萃取(SPE)-二维液相色谱法同时测定儿童配方奶粉中脂溶性维生素A、D₂、D₃和α-、β-、γ-、δ-维生素E含量的方法。样品经皂化后直接进样,以聚合物为填料的PLRP-S色谱柱为在线固相萃取柱净化皂化液,采用SPE泵反向洗脱目标组分,并通过引入在线稀释将目标组分聚焦在第一维色谱柱柱头。以NuovaSil^TM PFP(4.6 mm×150 mm,3μm)为第一维色谱柱,甲醇-0.1%甲酸水溶液为流动相进行梯度洗脱,分离维生素A和E的4种异构体。以ChromCore PAH(4.6 mm×150 mm,3μm)为第二维色谱柱,甲醇-乙腈(90:10,v/v)为流动相,分离维生素D₂和D₃。结果表明,维生素A在5.0～500.0 ng/mL、维生素D在1.0～100.0 ng/mL、维生素E在50.0～5000.0 ng/mL线性范围内线性良好,相关系数均大于0.9999。维生素A、D₂、D₃和α-、β-、γ-、δ-维生素E的...     

Determination of vitamin e in foods — a review

The vitamin E group includes tocopherols and tocotrienols and their isomers, esters, and derivatives. They differ not only in biopotencies as antisterility agents but also in activities in other physiological and chemical relationships. Unlike vitamins A and D, foods (vegetable oils) are among the richest sources of vitamin E, and assay methods for vitamin E include food applications more often than for the former vitamins. Phys‐icochemical methods are replacing bioassays for vitamin E and tocopherol wherever possible because of greater specificity and less variability, time, and, sometimes, expense. Unless careful purifications and isolations are carried out and some of the relative vitamin E activities of components are calculated, bioassays are still required for total vitamin E activity. The vitamin E group is separated by column, paper, thin‐layer, gas‐liquid, and high‐pressure liquid chromatography (HPLC): Gas‐liquid chromatography has been more successfully used for vitamin E than for other fat‐soluble vitamins. Recently developed HPLC methods for vitamin E are sensitive and apparently require less cleanup of extracts and less time than former methods; HPLC may prove to be the most useful technique for vitamin E in foods, especially if other fat‐soluble vitamins can be determined simultaneously on the same sample extract.     

Headspace Liquid-Phase Microextraction Followed by Gas Chromatography–Mass Spectrometry for Determination of Furanic Compounds in Baby Foods and Method Optimization Using Response Surface Methodology

In the present study, a sensitive, rapid, and simple method for determination of furanic compounds in baby foods has been developed. Headspace liquid-phase microextraction (HS-LPME) coupled with gas chromatography–mass spectrometry was used to extract and measure furan, 2-methylfuran, and 2,5-dimethylfuran in baby foods. Effective parameters such as salt amount (NaCl), stirring rate, temperature, and time of extraction were optimized using response surface methodology based on a central composite design to obtain the best conditions for extracting furanic compounds. The optimum parameter values were 1 g NaCl, 700 rpm stirring rate, 40 °C extraction temperature, and 15 min extraction time. The calibration curves were linear over the range of 0.2–200 ng?mL^?1 (R ² ?>?0.99) for all compounds, and the repeatability of the method, described as relative standard deviation, ranged between 3.84 and 7.06 % (n?=?6). The recovery of spiked baby food sample after extraction ranged between 89.33 and 103.64 %, and the best enrichment factor was achieved about 972-fold for furan. The limits of detection and quantitation ranged between 0.021 and 0.038 ng?g^?1 and 0.069 and 0.126 ng?g^?1, respectively. The merit figures of the HS-LPME/GC-MS method showed that it can be considered as a new, fast, and effective alternative method for investigating furanic compounds in baby foods.     

A survey of styrene monomer levels in foods and plastic packaging by coupled mass spectrometry—automatic headspace gas chromatography

An extensive UK survey of styrene monomer levels in styrene based plastic packaging materials and their contained foods (133 samples) has been carried out, examining a wide range of retail foods of different brand names and including yogurts, creams, salads, coleslaws, soft cheeses, margarines, hot and cold beverages from dispensing machines, spreads, fresh and cooked meats, candied fruits, fresh strawberries, and take-away ‘fast’ foods. Analysis by headspace gas chromatography of styrene levels in the plastic containers showed levels of monomer ranging from 16 to 1300 mg kg^?1 although the majority of containers (73%) had styrene levels in the range 100–500 mg kg^?1 and only five plastic tubs had levels exceeding 1000 mg kg^?1. Analysis of the food contents of the plastic containers by automated headspace gas chromatography with single ion monitoring mass spectrometric detection showed levels of the monomer ranging from < 1 μg kg^?1 to 200 μg kg^?1, although the majority of foods (77%) had styrene levels below 10 μg kg^?1, and 26% of the total number analysed had levels below 1 μg kg^?1.     

Fast analysis of caffeinated beverages using laser diode thermal desorption mass spectrometry (LDTD-MS/MS)

ABSTRACT

A rapid method for quantitative caffeine analysis in carbonated and non-carbonated beverages and liquid dietary supplement products was developed based on the direct sample introduction technique of laser diode thermal desorption atmospheric pressure chemical ionisation with tandem mass spectrometry (LDTD-MS/MS). Product samples were diluted with a mixture of methanol, water, and d₃-caffeine internal standard. Sample aliquots were filtered, spotted on a metal-lined LDTD microtitre plate, dried, and thermally desorbed for subsequent ionisation and analysis by MS/MS analysis. Each sample required a 6 s desorption, and sample-to-sample analysis time of less than 30 s per sample. Caffeine yielded a linear calibration curve over the range 0.5–100 μg mL^?1 (R² > 0.995). Caffeine recoveries from fortified samples ranged from 97% to 107% with <5% RSD. The caffeine determination was not affected by matrix interferences despite the large range of ingredients, vitamins, sweeteners, extracts, and additives present in the products tested, even though LDTD-MS/MS is a whole-sample desorption technique with no separation of matrix background. The method detection limit was below 0.12 μg mL^?1. The method was applied to 33 caffeinated products and LDTD-MS/MS quantitative results closely correlated (R² > 0.998) with the regulatory standard HPLC-UV method (AOAC Official Method 979.08).