Reversed phase HPLC analysis of α- and β-carotene from selected raw and cooked vegetables

Traditional AOAC colorimetric procedures for carotenoid analysis are known to lack specificity and accuracy. Newer HPLC methods provide the investigator with a more precise tool for carotenoid quantification in foods and tissues. In the present studies, reverse phase HPLC was utilized to evaluate the - and -carotene content in raw and cooked leaves of lettuce, spinach and winged bean as well as in the carrot root. The vegetables were boiled or steamed and the true retention of - and -carotene in the cooked products was determined. Boiling for 30 minutes resulted in a 53 and 40% loss of -carotene from lettuce and carrots, respectively. Full retention or even an increase in -carotene content in boiled winged bean leaves and spinach was noted. Steaming resulted in very good retention of - and - carotene in all vegetables (83–139% retention). Thus, although cooking procedures (especially boiling) may result in oxidative loss of carotenoids in some vegetables, heat treatment increases the chemical extractability of - and -carotene in others. The presence of carotenoproteins in some vegetables may effect the heat stability of extractability of - and - carotene.     

Effect of home processing on ascorbic acid and β-carotene content of spinach (Spinacia oleracia) and amaranth (Amaranthus tricolor) leaves

The present investigation was conducted to study the concentration of ascorbic acid and -carotene in spinach and amaranth leaves as affected by various domestic processing and cooking methods which included storage of leaves in polythene bags or without packing for 24 and 48 hours in refrigerator at 5 °C; at 30 °C in polythene bags; drying (sun and oven); blanching (5, 10, 15 min); open pan and pressure cooking. Ascorbic acid content of fresh leaves was 624.1 to 629.0 mg and -carotene content was 35.3 to 53.1 mg/100 g dry weight. The percent loss of ascorbic acid ranged from 1.1 to 6.3 and 55.3 to 65.9 while lower losses (0.0 to 1.3 and 1.5 to 2.1) of -carotene were observed in leaves stored in refrigerator and at 30 °C, respectively. A markedly greater reduction in ascorbic acid and -carotene was observed in dried, blanched and cooked leaves. The study recommended the storage of leaves in refrigerator, drying in oven, blanching for shorter time and cooking in pressure cooker for better retention of these two vitamins.     

Effect of traditional open sun-drying and solar cabinet drying on carotene content and vitamin A activity of green leafy vegetables

Dried green leafy vegetables constitute a major dietary source of provitamin A carotenoids for people living in semi-arid areas of Tanzania. In the present study, eight vegetable varieties commonly consumed in these areas were either traditionally sun-dried or solar-dried, and the amount of provitamin A carotenoids were determined by HPLC. In the fresh blanched leaves, the contents of -carotene, -carotene, 9-cis--carotene and 13-cis--carotene were in the range of 526–917, 12–39, 80–136 and 16–40 g/g dry matter/basis; dmb, respectively. The average amounts of all-trans--carotene in the leaves after blanching, solar drying and open sun-drying were 662, 502 and 353 g/g dmb, respectively, all significantly different from each other (p <0.001). The average amounts of all-trans--carotene were 21, 15 and 8 g/g dmb (p <0.05) and of 9-cis--carotene 101, 82 and 63 g/g dmb (p <0.05) in the blanched, solar-dried and open sun-dried samples, respectively. Estimation of the amount of retinol equivalents provided by the dried vegetables for preparation of an edible portion of 100 g relish showed that solar-dried vegetables contributed more (between 120–275%) than the recommended level of vitamin A, and on average 43% more retinol equivalents than relishes of open sun-dried vegetables.Thus, it is concluded that the amount of provitamin A-carotenes in traditionally treated vegetables were highly reduced by open sun-drying while solar drying resulted in significantly more retention of the carotenes. All-trans--carotene and 9-cis--carotene were similarly affected as all-trans--carotene by the two drying methods. Consumption of a 100 g portion of solar-dried vegetable relish could provide the recommended daily intake of vitamin A.     

Retention of quality characteristics of dehydrated green leaves during storage

Green leafy vegetables are the most underexploited class of vegetablesdespite high nutritional value. Reports on nutritional composition andstorage of some of the fresh leaves are available but the storage behaviorof dehydrated leaves apparently has not been studied. Therefore, in thepresent study, two green leafy vegetables, savoy beets (Beta vulgarisvar. bengalensis) and fenugreek (Trigonella foenumgraecum) were dehydrated in a low temperature drier and stored for9 months under ambient and cold stored conditions after packaging insingle or double layers of high density polyethylene film (200 gauge). Thequality was determined on the basis of retention of -carotene,ascorbic acid and chlorophyll, and the extent of browning during storage.Retention of these quality characteristics depended on the crop and storageconditions. Double packed and cold stored samples of fenugreek retained67% -carotene, whereas savoy beet leaves retained only 57% ofthe initial -carotene under similar conditions. Similarly, higherretention of ascorbic acid and chlorophyll, and lower browning wasobserved in double packed, cold stored samples. Results indicated theefficacy of double packed and cold stored samples over other combinations.     

Utilization of β-carotene fromSpirulina platensis by rats

The availability of -carotene from Spirulina as compared to standard all trans -carotene was studied by the liver and kidney vitamin A storage method. After 21 days of vitamin A depletion, the rats were repleted with -carotene from Spirulina and a standard source at two dietary levels (60 and 120 µg/day) for a 10 day period. At lower levels, the liver storage levels of vitamin A and the percent of -carotene absorption were comparable to those of the standard. At higher levels both these parameters of the Spirulina fed group were significantly (P<0.01) inferior to the standard source fed group. However, the Spirulina fed group showed better (P<0.05) growth than the standard fed group did at both low and high levels of feeding.     

Physical and biochemical properties of green banana flour

Banana flour prepared from two cooking banana varieties, namely Alukehel and Monthan, were evaluated for their physical and biochemical characteristics. The yields of flour averaged 31.3% for Alukehel and 25.5% for Monthan. The pH of the flour ranged from 5.4 to 5.7. The bulk density and particle size distribution were also measured. The average chemical composition (% dry matter) of the flours were as follows: crude protein, 3.2; crude fat, 1.3; ash, 3.7; neutral detergent fiber, 8.9; acid detergent fiber, 3.8; cellulose, 3.1; lignin, 1.0 and hemicellulose, 5.0. Carbohydrate composition indicated the flour to contain 2.8% soluble sugars, 70.0% starch and 12.0% non-starch polysaccharides. Potassium is the predominant mineral in banana flour. Fresh green banana is a good source of vitamin C, but almost 65% is lost during the preparation of flour. Oxalate content (1.1–1.6%) of banana flour is probably nutritionally insignificant. The overall results are suggestive of the potential of green bananas as a source of flour.     

Verbreitung des Wissens über die ‘innere’ Qualität von Gemüse und Obst in der Öffentlichkeit

Zusammenfassung Anhand praktischer Beispiele werden qualitätsrelevante Problemkreise vorgestellt und eingehend diskutiert, so Erzeugerberatung — Weg der Ware vom Erzeuger zum Verbraucher — Äußere Beschaffenheit — Innerer Wert — Präsentation der Verkaufsware — Erhaltung der Frische — Berücksichtigung ernährungsphysiologischer Kriterien. Es wird ein Publikationsmodell — bereits 1950 entwickelt — vorgeschlagen, das weite Kreise der Züchter, der Erzeuger, der Fabrikanten, des Handels und der interessierten Verbraucherschaft sowohl ansprechen als auch das Verständnis der einzelnen Gruppen untereinander wecken könnte.Denn letztlich sollte es doch im Bermühen des Erzeugers, des Transporteurs, des Handels, des Verarbeiters von Obst und Gemüse in erster Linie darum gehen, das Wohlergehen, die Gesunderhaltung des Verbrauchers im Auge zu haben. Das wäre jedenfalls die Vorstellung und Erwartung der ernährungsphysiologisch und ernährungs-hygienisch ausgerichteten Qualitätsforscher.

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Public extension about the inner Quality of Vegetables and Fruit

As usually practized in vegetable and fruit cultivation problems relevant to the inner quality are presented and discussed, e.g. Information of consumers, Shipping products from producer to consumer, External Quality — inner Quality — Offering of products — Conserving of freshness — Regarding the nutritional value.In order to evaluate these problems a close co-operation of breeders, producers, manufacturers, dealers and the interested consumers seem to be necessary. This is possible through a model and system of information, similar to the so-called AZA which were first published in 1950.

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Referat, gehalten auf der Sitzung der neukonstituierten Kommission Öffentlichkeitsarbeit der DGQ am 1.10.1976 in Geisenheim/Rhein.     

Some preliminary observations on treatments which increase and decrease the stability of β-carotene in preserved,moist leaf protein

-carotene in leaf protein extracted from some species is destroyed in a few days when incubated with salt as a preservative. Its shelf-life can be greatly extended by pretreatment with oxalate, ascorbate mercaptans, phenolic substances, extracts made from leaves in which carotene is more stable, and by tight compaction. Treatment with alum reverses the protective effect of these chemical pretreatments, it also increases the lability of carotene in leaf protein extracted from species which usually give a relatively stable product. In these preparations of leaf protein, which were heated to 90 °C during preparation, carotene is only partially extractable into some solvents which are miscible with water. It seems therefore to be present in more than one state, but differences in extractability could not be correlated with differences in lability.     

Influence of grain quality,heat, and processing time on the reduction of aflatoxin B1 levels in ‘tuwo’ and ‘ogi’: Two cereal-based products

During the production of tuwo from laboratory-contaminated corn (AFB₁:150 mcg/kg) and sorghum (AFB₁:87.5 mcg/kg) grains, reductions in the aflatoxin-B₁ levels of pastes boiled for 30 min and 60 min were found to be 68.0% and 80.8%, respectively. In the preparation of ogi from contaminated corn and sorghum grains, reductions of about 72.5% and 71.4%, respectively, were obtained after fermentation at ambient conditions. Reconstitution of ogi paste into a porridge (akamu) considerably reduced the AFB level.     

Isolation and Partial Characterization of Mango (Magnifera indica L.) Starch:Morphological,Physicochemical and Functional Studies

Mango (Mangifera indica) is a fruit that grows in tropical regions. The aim of this work was to isolate the starch from two varieties of mango highly consumed in Mexico (criollo and manila), and to evaluate its chemical composition, along with some morphological, physicochemical and functional properties. Mango starch had an amylose content of about 13%, the fat content of criollo variety starch (0.1–0.12%), was similar to that of commercial corn starch used as control (0.2%); both mango starches had higher ash amount (0.2–0.4%) than corn starch. Mango starches presented a smaller granule size (10 m) than corn starch (15 m), along with an A-type X-ray diffraction pattern with slight tendency to a C-type. All values of water retention capacity (WRC) increased with the temperature. When the temperature increased, solubility and swelling values increased and in general, mango starches had higher values than corn starch. Both mango starches had gelatinization temperatures lower than the control, butcriollo variety starch presented higher enthalpy values thanmanila variety and corn starches. Overall, it was concluded that due to its morphological, physicochemical and functional properties, mango starches could be a feasible starch source with adequate properties, suitable for using in the food industry.     

In Vitro Accessibility and Intake of β-Carotene From Cooked Green Leafy Vegetables and Their Estimated Contribution to Vitamin A Requirements

Provitamin A carotenoids from green leafy vegetables constitute a major dietary source of vitamin A in Tanzania. The efficiency of different vegetable preparations in contributing to the daily safe intake level of vitamin A for children was evaluated in the present study. The amount of bioaccessible (available for absorption) all-trans--carotene from green leafy vegetable dishes prepared either traditionally in households or with an improved method was estimated by an in vitro digestion method that simulates human digestion. The median vegetable portion size consumed by 34 children (2--12 years old) in the surveyed households was determined by weighing. The amount of all-trans--carotene available for absorption from the same type of vegetables cooked without oil by traditional or a modified method ranged from 5 to 12% and 4 to 15%, respectively. Vegetables cooked with modified method with oil had 2–5 times higher amount of in vitro accessible all-trans--carotene than vegetables cooked without oil. A median portion (84 g) of such a relish then provided 88–477% of the daily safe intake level of vitamin A, while portions cooked without oil only provided between 23 and 46%. In this study, a wide variation in all-trans--carotene content and bioaccessibility among studied green leaves was obtained. Still, to supply daily safe intake level of vitamin A for children from a median vegetable relish portion it is necessary to add oil in the preparation.     

Zusammenhänge zwischen den für die Blaufleckigkeit der Kartoffelknolle verantwortlichen Inhaltsstoffen

Zusammenfassung Mit der Faktorenanlyse nach der Hauptachsenmethode und der aufbauenden multiplen Regressionsanalyse, unter Einbeziehung von 56 Einflußgrößen, konnte gezeigt werden, daß die Blaufleckigkeit von Kartoffelknollen im wesentlichen vom Gehalt an Trockensubstanz, -Aminobuttersäure, Lysin, Isochlorogensäure und den Mineralstoffen Ca und K abhängt. Eine kausale Erklärung des gesamten Komplexes Blaufleckigkeit ist allerdings zum gegenwärtigen Zeitpunkt noch nicht möglich.

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Relationships between black spot of potatoes and several constituents of the tuber. With a factorial analysis and a multiple regression analysis could be shown that from 56 investigated constituents of the potato tuber only the dry matter content, aminobutyric acid, lysine, isochlorogenic acid, and potassium and calcium content influence the appearance of black spots.A causal explanation of the black spot phenomenon at present is not possible. Further investigations are necessary.

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Résumé Relations entre la tâche noire des pommes de terre et divers constituants du tubercule.L'analyse factorielle, l'analyse de la régression multiple ont pu démontrer que sur 56 constituants déterminés dans le tubercule de pomme de terre seuls l'acide aminobutyrique, la lysine, l'acide isochlorogénique, le taux de potassium et de calcium agissent sur la formation de la tâche noire.Une explication causale du phénomène tâche noire n'est pas encore possible pour l'instant. De nouvelles recherches sont nécessaires.

     

On determination of chitin content in mushrooms

Nitrogen compounds constitute the greatest proportion of the dry weight of mushrooms. These nitrogen compounds are partly protein and partly non-protein. A modified Heneberg-Stohman's method was used to separate non-protein from protein nitrogen, as well as to determine raw fiber content in mushrooms, since the methods used previously for this purpose are time-consuming and complicated. Elemental analysis of crude fiber was performed to confirm the uniformity of isolated products. The content of total crude fiber (fungin) and the proportion of chitin and cellulose in it were determined. The chitin content of 15 species of field grown edible mushrooms was in the range of 1.87–6.93% of total dry mass and 34.51–67.72% of isolated fungin.     

Production,nutritional profiles and storability of ‘aadun’ and ‘kokoro’: Two corn products

Aadun and kokoro were produced from maize grains by processes involving roasting, kneading, spicing, and frying. Aadun with a moisture content (MC) of 12.5%, pH 5.3 had the following composition: crude protein, 7.49%; fat, 28.5%; total carbohydrate, 60.0%; ash, 3.0% and energy value, 3,600 kcal/kg whilst kokoro with a MC of 16% and pH 5.1 had, respectively: 6.42%; 22.9%; 66.6%; 2.84% and 3,550 kcal/kg. Whilst aadun and kokoro stored under ambient conditions (28±2°C; 75–80% RH) became mouldy within 7 days, samples treated with 1% butyl paraben did not develop off-colour and mouldiness.     

Das Vorkommen der für Mensch und Tier essentiellen Aminosäuren in Vitalzonen (Aktivzonen) und in Speichergeweben einiger niederen und höheren Pflanzen

Zusammenfassung Eine Auswertung von etwa 15 000 mikrobiologischen Bestimmungen von essentiellen Aminosäuren (EAS) in Nahrungspflanzen bzw. deren Teilorganen und anatomisch differenzierten Zonen ergaben biochemische Zusammenhänge, die zu folgenden Schlüssen führten:Die bisher auf die menschliche Nahrung und das tierische Futter beschränkten Begriffe, essentielle Aminosäuren und EAS-Index nachB. L. Oser, die somit termini technici der Human- und Tierernährung darstellen, bedürfen einer Erweiterung auf die Pflanze, da die für das Tier lebensnotwendigen Aminosäuren nach unseren Befunden auch eine analoge Bedeutung für die Lebensfunktionen der Pflanze besitzen.In bestimmten pflanzlichen Gewebezonen, in denen Zellteilungen oder andere für das Leben der Pflanze entscheidend wichtige Prozesse ablaufen, findet sich eine im Verhältnis zum Rohprotein günstige Anreicherung essentieller Aminosäuren, die wiederum zu einer hohen Biologischen Eiweißwertigkeit führt, ausgedrückt als EAS-Index nachB. L. Oser, während andere Zonen, z.B. Speichergewebe, nur niedrige EAS-Indices aufweisen.Aus diesem Grunde wird vorgeschlagen, solche mit Vitalprozessen verknüpften pflanzlichen Gewebezonen zur besseren Kennzeichnung ihrer ernährungsphysiologischen Bedeutung für Mensch und Tier Vitalzonen oder — gemäß einem Vorschlag vonJ. Kisser, Wien — Aktivzonen zunennen.Beweise für die Richtigkeit der Überlegungen, die zu dieser Benennung führen, werden durch ein umfangreiches Untersuchungsmaterial geliefert.

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Summary About 15 000 microbiological determinations of essential amino acids (EAA) in food plants respectively in their different organs and in differentiated zones (as regard anatomy) showed biochemical relations, which lead us to the following conclusions:Untill present notions as Essential Amino Acids and the EAA-Index (B. L. Oser) are termini technici of human and animal nutrition. They are restricted to the metabolism of men and animals. According to our investigations those notions have to be extended, as the essential amino acids — essential for men and animals — are obviously essential for life function in plants too.In certain zones of plant tissue, where cell division or other active processes, important for plant life, take place, we find a favorable increase of essential amino acids, leading to a high biological value of proteins (EAA-Index according toB. L. Oser), while other zones, e.g. storage tissues, have only a low EAA-Index.In order to better mark the signification (as regard human nutrition) we propose to call those active plant tissues showing a high EAA-Index: Vitalzonen (vitalzones) oder — according toJ. Kisser-Wien — Aktivzonen (active zones).An extensive experimental material justifies the accuracy of our deduction and the necessity of the new term.

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Résumé Environ 15 000 dosages microbiologiques des acides aminés essentiels (EAA) dans les plantes alimentaires, dans leurs organes ou dans les zones anatomiques différenciées ont donné des relations biochimiques qui ont abouti aux conclusions suivantes:Jusqu'à présent les notions acides aminés essentiels et Indice d'amino acides selonB. L. Oser (les deux comme termini technici de l'alimentation des hommes et des animaux) sont limitées à la nourriture de l'homme et au fourrage des animaux. Mais nos travaux expérimentaux montrent que cette notion doit être étendue aux plantes puisque les acides aminés essentiels sont également essentiels pour les fonctions vitales des plantes.Dans certains tissue végétaux dans lesquels se produisent les divisions cellulaires, ou dans les zones qui sont très importantes pour les opérations du métabolisme végétal, on trouve une augmentation favorable des acides aminés essentiels, par rapport à la protéine brute. Cette augmentation amène une haute valeur biologique des protéines (Indice selonB. L. Oser), tandis que d'autres zones (par exemple les tissus de réserve) n'ont qu'une valeur biologique faible.C'est pourquoi nous nous proposons — pour bien marquer leur importance nutritive — de nommer ces tissus vitaux — qui dirigent le métabolisme végétale: Vitalzonen (zones vitales) ou selonJ. Kisser-Wien: Aktivzonen (zones actives).Notre opinion se fonde sur un ensemble considérable de données experimentales.

     

Protein quality and digestibility of new high-lysine barley varieties in growing rats

Four new high-lysine barley mutants, the variety Lysimax, with the high-lysine genelys3a and the mutants mother variety Sultan were grown in a field trial in 1993 at Risø, Denmark. Mutants 609, 1242, 1385 and 1405 yielded in the range of 89 to 98 percent and cv Lysimax yielded 102 percent of cv Sultan (100 percent). One-thousand kernel weights for the mutants were in the range of 87 to 97 percent and cv Lysimax 83 percent of cv Sultan (100 percent). Protein contents of the mutants were slightly higher, in the range of 13.2 to 13.6 percent, than of cv Sultan (13.1 percent) and Lysimax which had a protein content of 12.6 percent. Fat content was higher in Lysimax and in the mutants except for mutant 1385 than in cv Sultan while dietary fibre contents of the barleys were similar. The levels of -glucans and starch were usually lower in Lysimax and in the mutants. The highest lysine levels: 4.6, 4.0 and 3.7 g/16 g N occurred in cv Lysimax and mutants 609 and 1405 compared to 3.3, 3.3 and 3.2 for cv Sultan and mutants 1242 and 1385, respectively. Mutants 609 and 1405 and cv Lysimax also had higher levels of threonine, histidine and valine. The increased lysine contents resulted in large, at most 20 percent, increases in biological value; 88.8, 81.7 and 78.3 percent for cv Lysimax and mutants 609 and 1405 compared to 74.2 percent for cv Sultan. True protein digestibilities and energy digestibilities were slightly lower in Lysimax than in Sultan, 5.3 and 4.3 percentage units, respectively. It is concluded that the development of high-lysine barley varieties is very beneficial for meeting the requirements of indispensable amino acids for humans and monogastric animals. In addition, nitrogen excretion into the environment is drastically reduced due to the higher biological values of the mutants.     

Effect of alkaline treatment (‘akanwu’) and supplementary value of corn or crayfish on the protein quality of breadfruit (Treculia Africana)

The effect of treatment and supplementary value of corn (C) or crayfish (CR) on the protein quality of breadfruit (Treculia Africana) flours were studied in eighteen young rats. The 7030 or 701515 (Protein basis) combinations of breadfruit flours and corn or crayfish or both provided 1.6g N/100 g diet for the 35 day study. The addition of akanwu to the cooking water reduced cooking time and crude protein and saved fuel. The addition of akanwu and replacement of CR with C was not beneficial as judged by the parameters tested except for the wt. gain and PER. On the other hand, when crayfish was the only source of supplementary protein (30%) to breadfruit cooked without akanwu there were increases in all parameters tested over those with added akanwu except for the N intake, wt. gain, and PER.These results appear to suggest that addition of akanwu to TA was detrimental to its protein utilization and that TA appears to be an economic source of N in areas where it is a staple. Based on the results of this study, one would suggest that the use of akanwu as a tenderizer should be seriously looked into before further use.     

Influence of growth conditions on the value of crisphead lettuce

The marketable and nutritional quality of crisphead lettuce as affected by nitrogen supply, cultivar, and plant age at harvest was investigated in six plantings during 1989 and 1990. The optimum yield of marketable heads was obtained at a total nitrogen supply of 150 kg N per ha although only small differences were observed to the yield at 100 and 200 kg total N per ha. The total nitrogen supply included the amount of mineral nitrogen within the rhizosphere. The incidence of dry tipburn in older leaves was clearly decreased by an increased nitrogen supply, especially at late planting. The content of nitrate was increased and the content of dry matter and vitamin C decreased with increased nitrogen supply. The vitamin C content was higher for the cultivar Marius than for Saladin. As plants got older, the nutritional quality of crisphead lettuce decreased because the content of nutrients, especially vitamin C, decreased with increased plant age at harvest.     

Microbiological evaluation of tofu and tempeh during processing and storage

Tofu samples consisting of Fresh Tofu, Herb Tofu, Tofu Paste, Fried Tofu, Tofu Burger, Smoked Tofu and different types of herbs used for making Herb Tofu were analysed for their microbiological load. Tempeh samples consisted of cook water, inoculated beans and fresh tempeh. Fresh Tofu and Herb Tofu had high bacterial counts (10⁵ cfu/g). Tofu Burger and Smoked Tofu had counts around 10⁴ cfu/g. Tofu Paste and Fried Tofu had low counts (<10² cfu/g). Cutting board, knife and frequent hand contact with product were the major sources of contamination for tofu. Herbs used for making Herb Tofu were highly contaminated (>10⁵ cfu/g). Cook water and cooked beans for tempeh production had lower counts (10⁴ cfu/g). Initial count of fresh tempeh was high (about 10⁸ cfu/g). Most products had counts of >10⁶ cfu/g after 7 days of cold storage. The microbiological quality of the product may improve if producers avoid unnecessary contamination during processing.     

Nutritional composition of selected green leafy vegetables,herbs and carrots

Six green leafy vegetables and herbs – spinach, amaranth, bengal gram, cauliflower, mint, coriander and carrots – were analyzed for moisture, protein,ascorbic acid, -carotene, total iron, ionizable iron (as % of total iron) in vitro iron (% of total iron), copper, manganese and zinc. Moisture content of the leaves and carrots varied from 75.1 percent (bengal gram) to 95.4 percent (carrot) and protein from 9.83 percent (carrots) to 30.9 (mint) percent. Ascorbic acid, -carotene, total iron and ionizable iron contents were at a maximum in case of bengal gram leaves whereas level of ionizable iron and in vitro iron as a percent of total iron was highest in carrots. Copper, manganese and zinc contents were maximum in spinach.