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1.
In the western Sahel, indigenous plants become important staples when cereal harvests are inadequate to support populations inhabiting that region of Africa. The purpose of this study was to assess the nutrient content of several of these edible wild plants. The leaves of the following seven plant foods were analyzed: Ziziphus mauritiana, Cerathotheca sesamoides, Moringa oleifera, Leptadenia hastata, Hibiscus sabdarifa, Amaranthus viridi, and Adansonia digitata. The fatty acid, vitamin E, carotenoid, selected mineral and amino acid contents of these plant foods were determined. These same analyses were performed on the fruit of the Adansonia digitata. In quantitative and qualitative terms, Amaranthus viridis was found to be an excellent source of protein. Its amino acid composition compared favorably to that of a World Health Organization (WHO) protein standard. It also contained considerable amounts of the two fatty acids that are essential in humans (linoleic and -linolenic) and a number of minerals including iron, magnesium, calcium and zinc. The leaves of Hibiscus sabdarifa contained an appreciable quantity of protein the composition of which was comparable to the WHO standard. The mineral content of the leaves of this plant was also exceptionally high; noteworthy was its high zinc content. H. sabdarifa also contained significant quantities of the two essential fatty acids. Ziziphus mauritiana was an excellent source of the essential fatty acid linoleic acid and several of the metals including iron, calcium, magnesium and zinc. Its content of other essential nutrients, however, was rather low. In general, Adansonia digitata leaves were nutritionally superior to the fruit of the tree; however, the fruit did contain useful quantities of potassium, phosphorus, zinc and -linolenic acid. The Leptadenia hastata leaves were an especially good source of lutein and -carotene. These data should be useful to the people who inhabit the western Sahel in helping them devise healthy diets during times when cereal staples are in short supply.  相似文献   

2.
Wheatchapati, wheat+Bengal gram (8020 and 7030)chapatis and casein diets, at 10 percent protein level, were fed to rats for 12 weeks to study the effect on calcium utilization. The supplementation of Bengal gram to wheat diets significantly improved the calcium absorption. The urinary calcium excretion in wheat+Bengal gramchapati diets was significantly less than that of wheatchapati diet fed group. The in vivo45Ca absorption (CPM/100 l serum) was also less in wheatchapati group as compared to wheat+Bengal gramchapati diets fed groups. The supplementation of legumes to cereals improved the calcium utilization and it may be concluded that there will be no risk of occurance of protein induced hypercalciuria.  相似文献   

3.
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.  相似文献   

4.
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.  相似文献   

5.
The composition and quality of edible tender stems or cladodes of 3 Prickly Pear Cactus species (Opuntia amyclaea, O. ficus-indica, and O. inermis) were studied at different stages of development. This traditional Mexican vegetable is called nopalitos in Spanish and cactus leaves in English. Cladodes harvested when 20 cm in length have the following average composition per 100 g: 91.7 g of water, 1.1 g of protein, 0.2 g of lipid, 1.3 g of ash, 1.1 g of crude fiber, 4.6 g of complex carbohydrates and 0.82 g of simple sugars, 12.7 mg of ascorbic acid and 28.9 µg of carotenes. The cladode's juice has an average pH of 4.6, 0.45% titratable acidity and 6.9% soluble solids. The components which varied most during development of the cladodes were: carotenes, acidity and total carbohydrates which increased, and protein and crude fiber (acid-detergent) which decreased. The nutritive value of the tender cladodes in the stages of growth at which they are commonly harvested and consumed (15 to 25 cm long weighing 50 to 80 g per stem), was similar for the 3 species.  相似文献   

6.
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.  相似文献   

7.
The impact of various endopeptidases on the nature of protein digestion products was measured with the digestion cell technique. After a 30 min pepsin pre-digestion, casein and rapeseed concentrates were hydrolyzed with various amounts of pancreatin, trypsin and/or chymotrypsin. This hydrolysis was performed in a dialysis tube (molecular weight cut-off 1000) with continuous collection of the digested material. The addition of pure trypsin or chymotrypsin to pancreatin (Enzyme:Substrate 125) did not change the digestibility of casein. Only a higher pancreatin level (Enzyme: Substrate 112.5) increased the total protein digestibility without affecting the amino acid spectra. Rapeseed digestibility was markedly increased by the addition of pure trypsin to pancreatin. Lysine and arginine, target amino acids of trypsin, were favored at the expense of chymotrypsin and elastase target amino acids. Supplementation of pancreatin with, chymotrypsin enhanced rapeseed digestibility without affecting the relative amino acid digestibility. The impact of a higher pancreatin ratio (Enzyme: Substrate 112.5) was similar to that of enriched pancreatin but the rate of amino acid release was modified. The differences between protein sources were mainly attributed to protein structure.  相似文献   

8.
A field experiment was carried out to study the effect ofcooking on protein solubility profiles of mycorrhizal inoculated, phosphorusand sulphur fertilized faba beans under two water regimes. The resultsindicated that cooking significantly (p 0.05) increasedthe G3-glutelin fraction as well as the insoluble protein butsignificantly (p 0.05) decreased the globulin and albuminfractions; prolamin, G1-glutelin and G2-glutelin fractionswere slightly increased. Mycorrhizal inoculation and mycorrhiza +phosphorus + sulphur fertilization significantly (p 0.05) increased albumin content. All fertilizer treatments significantly (p 0.05) decreased the insoluble protein.  相似文献   

9.
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.
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.
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.
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10.
Biochemical changes occurring during the development of cork spot of York Imperial were investigated. At the first visible sign of the disorder, the rate of ethylene production increases in the affected tissue. Respiration also increases, acetate being the major respiratory substrate rather than glucose. Protein synthesis, pectin synthesis, and the movement of inorganic ions into the tissue follow. During the time the chemical changes are taking place in the tissue, abnormal cell division is initiated, packing the newly-formed cells into the intercellular spaces. At the final stage of development, the tissue becomes brown and appears as a firm brown spot in the flesh of the apple. Cork spot is somewhat different from bitter pit in that the spots appear early in the season, the affected tissue is deeper in the flesh, and firmer. The chemical changes discovered so far in both disorders, however, appear to be similar. We consider the abnormal chemical changes that occur in both disorders to be common to diseases and injuries and not specific for either cork spot or bitter pit.
Zusammenfassung Die Untersuchungen erstreckten sich auf biochemische Veränderungen, die während der Entwicklung von cork spot bei Äpfeln der Sorte York Imperial auftreten. Beim ersten sichtbaren Anzeichen der Störung steigt die Rate der Äthylenbildung im befallenen Gewebe an. Auch die Atmung nimmt zu, wobei Acetat das grössere Atmungsprodukt darstellt als Glucose. Protein- und Pektin-Synthese sowie Bewegung anorganischer Ionen in das Gewebe folgen. Während der Zeit chemischer Veränderungen im Gewebe beginnt eine abnorme Zellteilung, indem die neugebildeten Zellen in die interzellularen Zwischenräume eingebaut werden. Im Endstadium der Entwicklung wird das Gewebe braun und erscheint als fester Fleck im Fleisch des Apfels. Cork spot unterscheidet sich etwas von der Stippigkeit dadurch, dass die Flecken früher in der Saison erscheinen, sich die befallenen Gewebe tiefer im Fleisch befinden und fester sind. Die chemischen Veränderungen beider Störungen scheinen sich — soweit sie bekannt sind — zu ähneln. Wir glauben, dass die chemischen Veränderungen, die bei beiden Störungen auftreten, allgemein für Krankheiten und Verletzungen zutreffen und nicht entweder für Stippigkeit oder cork spot spezifisch sind.
Resume Quelques changements biochimiques se produisant pendant le développement du cork spot chez la York Imperial ont été étudiés.Au premier signe visible de désordre, la vitesse de production d'éthylène augmente dans le tissu atteint. La respiration augmente également; l'acétate devient le substrat principal de la respiration, plutôt que le glucose. Une synthèse de protéines, de pectine, ainsi que des déplacements d'ions inorganiques dans le tissu se produisent ensuite.Pendant que les changements biochimiques ont lieu, une division cellulaire anormale est initiée, et les cellules nouvellement formées s'accumulent dans les espaces intercellulaires.Au stade final de développement, le tissu devient brun et apparaît comme une tache brune et ferme, dans la chair de la pomme. Le cork spot diffère quelque peu du bitter pit par le fait que les taches apparaissent tôt dans la saison, le tissu malade étant localisé plus profondément dans la chair, et plus ferme. Les modifications chimiques trouvées dans les deux maladies paraissent cependant être similaires. Nous considérons ces changements chimiques comme propres aux maladies et blessures en général et comme non spécifiques, ni du cork spot, ni du bitter pit en particulier.
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11.
Summary A comparative study has been carried out on amylase, urease and trypsin-inhibiting activities in the soybean varieties Adams, Harosoy and Lincoln and in soybean plant material of Harosoy. No significant quantitative difference was found between these activities in the three varieties. Two pH optima, at 5.5 and at 6.4 were found for amylase activity from all three varieties of soybeans. Although the temperature of 60° was most favourable for Adams-, Harosoy-and Lincoln-amylase, the latter lost almost all its activity at 70° whereas that of Adams remained constant.No urease and trypsin-inhibiting activities and only slight amylase activity could be detected in the leaves, stems and empty pods of the soybean plant. Young seeds (three weeks after setting) were compared, on the basis of dry weight, to mature seeds and were found to contain 50% of the trypsin inhibiting activity, 34% of the amylase and only 3% of the urease of the latter.
Zusammenfassung Eine vergleichende Studie wurde durchgeführt über Amylase-, Urease- und Trypsin-hemmende Wirkung der Sojabohnen-Sorten Adams, Harosoy und Lincoln sowie in Sojabohnenpflanzen der Sorte Harosoy. Keine mengenmäßig-signifikanten Unterschiede in der Wirkung fanden sich bei den drei Sorten. Zwei pH-Optima ergaben sich für die Amylase-Aktivität der drei Sojabohnen-Sorten bei 5,5 und 6,4. Obwohl die Temperatur von 60° sehr günstig für die Amylase der Sorten Adams, Harosoy und Lincoln war, verlor die Amylase der letztgenannten Sorte fast ihre gesamte Wirksamkeit bei 70°, während die der Sorte Adams dabei konstant blieb.Keine Urease- und Trypsin-hemmende Wirkung und eine nur leichte Amylase-Aktivität konnte in den Blättern, Sproßachsen und in den leeren Hülsen der Sojabohnen-Pflanze nachgewiesen werden. Junge Samen (drei Wochen nach der Aussaat) wurden auf Trockengewichtsbasis mit reifen Samen verglichen. Es wurde bei den jungen Samen — im Vergleich zu den reifen — eine nur 50%ige Trypsin-hemmende Wirkung, eine 34%ige der Amylase und eine nur 3%ige der Urease ermittelt.
Resumen Se ha efectuado un estudio comparativo sobre las actividades de la amilasa, la ureasa y el inhibidor de la tripsina en las variedades de porotos de soya Adams, Harosoy y Lincoln, así como en algunas partes vegetativas de la variedad Harosoy. No se encontraron ningunas diferencias cuantitativas entre las actividades de estas variedades. Se encontraron dos valores optimales del pH, 5.5 y 6.4, para la amilasa de todas las tres variedades de porotos de soya. Aunque la temperatura más favorable para la amilasa de las variedades Adams, Harosoy y Lincoln fuera 60°, esta última perdió casi toda su actividad a 70°, mientras que la actividad de la variedad Adams se quedó sin cambiar.No se pudo demostrar la presencia de ureasa y actividad inhibidora de la tripsina en las hojas, los tallos y las cápsulas vacías de las plantas de soya, y se encontró solamante una ligera actividad de amilasa en estas partes vegetativas. Se compararon, en base seca, semillas nuevas (a las tres semanas de formarse) con semillas maduras. Se encontró que las primeras exhibieron 50% de la actividad inhibidora de la tripsina, 34% de la actividad de amilasa y solo 3% de la actividad de ureasa, en comparación con las actividades de las semillas maduras.
Resumé Une étude comparative a été faite sur les activités de l'amylase, l'uréase et l'activité inhibitrice de la trypsine, dans les variétés de fèves de soya: Adams, Harosoy et Lincoln ainsi que sur différents stades de l'appareil végatatif du soya Harosoy. Aucune différence quantitative, significative, ne fut trouvée entre les activités dans les trois variétés. Deux pH optima à 5.5 et à 6.4 furent trouvés pour l'activité de l'amylase de toutes les trois variétés de fèves de soya. Bien que la témperature de 60° fut la plus favorable pour l'amylase de Adams, Harosoy et Lincoln, l'amylase de ces 2 derniers perdit presque toute son activité à 70° tandis que l'amylase dAdams resta constante.Ni activité d'urease, ni activité inhibitrice de trypsine ainsi que très peu d'amylase ne furent observés dans les feuilles, tiges et gousses vides de la plante soya. De jeunes semences (trois semaines après la fécondation) furent comparées, sur la base du poids sec, à des semences adultes et furent trouvées contenir 50% de l'activité inhibitrice de la trypsine, 34% de l'amylase et rien que 3% de l'uréase par rapport aux graines adultes.

with 3 figs.  相似文献   

12.
Nutrient content of the edible leaves of seven wild plants from Niger   总被引：1，自引：0，他引：1  
Wild plants play an important role in the diet of the inhabitants of Niger. These plants tend to be drought-resistant and are gathered both in times of plenty as well as times of need. Used in everyday cooking, famine foods may be an important source of nutrients. The goal of this study was to investigate the nutritional role of wild plants in the nigérien diet. To this end, leaves of seven plants species were analyzed for their mineral, amino acid and fatty acid contents: Ximenia americana, Amaranthus viridus, Corchorus tridens, Hibiscus sabdarifa, Maerua crassifolia, Moringa oleifera, and Leptadenia hastata. Ximenia americana} contained large amounts of calcium. Large quantities of iron were present in Amaranthus viridus. All seven plants contained significant amounts of selenium and phosphorus. Corchorus tridens contained the most protein (19–25% dry weight), and its composition compared favorably to the World Health Organization's standard for essential amino acids. Moringa oleifera contained 17% protein and compared favorably with the WHO standard. Corchorus tridens contained the largest amounts of the two essential fatty acids linoleic and -linolenic acids. These results reinforce the growing awareness that wild edible plants of the Western Sahel can contribute useful amounts of essential nutrients, including amino acids, fatty acids and trace minerals, to human diets.  相似文献   

13.
Seed globulins ofCajanus cajan a widely cultivated legume were purified and characterised. About 78% of the seed proteins were salt soluble, out of which 61% were globulins which were further separated into three fractions. The fraction was insoluble at pH 4.7 and consisted of two subfractions. Fraction and were soluble at pH 4.7. All the fractions were characterised as glycoproteins by cesium chloride centrifugation. The proteins consisted of subunits which were not held together by covalent disulphide linkages. Amino acid analysis of the different globulin fractions showed that the fraction was comparatively rich in sulphur amino acids.  相似文献   

14.
Zusammenfassung Zur Untersuchung der Rückstandsbildung in Möhren und Zwiebeln nach Saatgutinkrustierung mit Aldrin, wurde ein Versuch in Mitscherlich-Gefäßen in einem Phytotron durchgeführt. Wir inkrustierten Saatgut von Möhren der Sorte Juwarot und Zwiebeln der Sorte Zittauer Gelbe mit einer frisch bereiteten, gereinigtes14C-Aldrin enthaltenden, Formulierung. Dabei wurden in etwa praxisübliche Aufwandmengen eingesetzt.Der Transport des Pflanzenschutzmittels und seiner Abbauprodukte in die wachsende Pflanze und die Speicherung in den zum Verzehr gelangenden Pflanzenteilen konnte dabei durch autoradiographische Untersuchungen deutlich verfolgt werden. In den Möhren befanden sich Rückstände im Bereich des Periderms und sind somit als kutikulär zu klassifizieren. Bei der untersuchten Sorte zeigte das Mittel eine sehr hohe Persistenz, da praktisch unverändertes Aldrin wiedergewonnen wurde. Auch Kochen und Lagerung beeinflußte weder Art noch Höhe der Rückstände, die mit durchschnittlich 0,35 ppm relativ hoch lagen.Bei den Zwiebeln fanden wir Rückstandswerte, die im Durchschnitt mit 0,03 ppm relativ gering waren. Im eßbaren Anteil befanden sich Rückstände nur in der Zwiebelscheibe, von der bei haushaltsmäßiger Verwendung stets geringe Anteile mit in die Nahrung gelangen. Chromatographische Untersuchungen zeigten, daß im eßbaren Anteil nur Dieldrin als Rückstand vorkommt.Die Verteilungsstudien ergeben für die Rückstandsanalytik wichtige Hinweise. Besonders die starke Anreicherung des Mittels in den Keimblättern eröffnet beispielsweise dem Hersteller von diätetischen Nahrungsmitteln im Vertragsanbau die Möglichkeit, bereits im Keimblattstadium — also schon sehr frühzeitig — Auskunft über eine etwaige Kontamination zu erhalten. Wegen der besonders intensiven Aufnahmebereitschaft für fettlösliche Pestizide, kann man die Möhre gewissermaßen als Testpflanze verwenden.
Contributions to the metabolism of the pestecide Aldrin in food plantsSeeds of carrots and onions incrusted with14C-Aldrin
Seeds, incrustated with labelled insecticide were used in studies of the absorption, translocation and transformation of Aldrin in carrots (Juwarot) and onions (Zittauer Gelbe). The seeds were treated with14C-Aldrin at levels close to those used in practice, and grown in Mitcherlich pots in a phytotron.The transport of14C-Aldrin into the growing plants and the accumulation of residue in the edible parts were followed by autoradiography.In carrots the residues were shown to be located in the periderm tissue; the average Aldrin content was found to 0.35 ppm. The persistence of the incorporated Aldrin was very high and no degradation products could be detected by thin layer chromatography.Neither cooking, nor storage at room temperature till putrefaction produced a change in the Aldrin level.The level of residue in onion was relatively low, of the order of 0.03 ppm and as far as the edible part of the onion is concerned it accumulated only in the onion sprout at the base of bulb. Thin layer chromatography indicated complete transformation into Dieldrin.These distribution studies point to useful approaches in residue analysis. The accumulation of residues in cotyledons thus allows the manufactures of dietetic food to obtain information about the potential level of the product very early in the season.The carrot could be used as a test plant owing to its intensive accumulation of fat soluble pesticides.
Résumé Afin d'étudier la répartition des résidus de pesticides chez la Carotte et l'Oignon, après traitement des semences par l'aldrine, nous avons réalisé une culture en vases de Mitscherlich dans un phytotron. Nous avons imprégné des graines de carottes de la variété Juwarot et d'oignons de la variété Zittauer Gelbe avec une préparation récente contenant de l'aldrine14C purifiée. Les quantités employées furent celles en usage dans la pratique agricole.Le transport du pesticide et de ses dérivés dans la plante en croissance, son accumulation dans les parties comestibles, ont pu être suivis de façon précise par les techniques d'autoradiographie. La carotte montra des résidus dans le périderme, résidus à considérer comme cuticulaires. L'aldrine se révéla hautement persistante, car elle a été retrouvée pratiquement non transformée. Ni le stockage, ni la cuisson n'ont fait varier le taux ou la nature des résidus qui furent relativement élevés (0,35 ppm) en moyenne.L'oignon montra des taux de résidu relativement faibles, de 0,03 ppm. Dans la partie comestible, seul le disque contient du pesticide, organe dont une très faible partie est utilisée en cuisine. Les recherches chromatographiques ont montré que seule la dieldrine pénètre dans les parties comestibles.L'étude de la répartition des pesticides au cours du développement est fort instructive. Ces substances s'accumulent au départ dans les cotylédons; les cultivateurs travaillant sous contrat pour la production d'aliments diététiques ont ainsi le moyen de reconnaître très tôt, dès la germination, une contamination éventuelle. La carotte, qui accumule si facilement des pesticides liposolubles, peut servir en quelque sorte de plante test.
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15.
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.
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.

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

16.
Twenty three cultivars of carrot (Daucus carota L.) roots consisting of fifteen local and eight exotic cultivars were analysed for various chemical constituents including dry matter, total soluble solids (TSS), -carotene, total and reducing sugars, phenolics, phosphorus, zinc, manganese, copper, iron, sodium potassium and ash. In addition other characteristics such as days to maturity, root weight and length, flesh thickness, core diameter, number of forked and cracked roots per plot have been studied. Yellow carrots were found to have maximum root length, water soluble carbohydrates and minimum -carotene content. The exotic cultivars were found to have higher TSS content than the local cultivars, while the latter cultivars had higher mineral contents than the former. However, on the average, dry matter content, total water soluble sugars, reducing and non-reducing sugars were found to be greater in exotic cultivars than in local ones, but -carotene, phenols and phosphorus contents were greater in local cultivars. A significant positive correlation between -carotene content, ash percentage and days to maturity was observed. A wide variation in chemical constituents and plant characteristics was observed indicating a high genetic variability in the material under study.  相似文献   

17.
Ndaleyi, a fermented, sun dried agglomerated powder produced from pearl millet or sorghum is one of the most popular foods consumed in Nigeria, mostly by the Kanuri people of Borno State. Its traditional production is described. The mean yields ofndaleyi (mainly starch),chir (millet gluten) and bran (overtail orbina) were 30.6, 22.5 and 21.5%, recpectively. A mean yield loss of 20% was observed. Chemical analysis revealed thatchir and bran have higher protein, fat and ash contents thanndaleyi. The titratable acidities (as percent lactic acid) ofndaleyi andchir were 0.9 and 0.3, while their pH values were 3.3 and 3.5, respectively.  相似文献   

18.
Proximate composition and mineral content of raw and cooked leaves of two edible tree spinach species (Cnidoscolus chayamansa and C. aconitifolius), known locally as chaya, were determined and compared with that of a traditional green vegetable, spinach (Spinicia oleraceae). Results of the study indicated that the edible leafy parts of the two chaya species contained significantly (p<0.05) greater amounts of crude protein, crude fiber, Ca, K, Fe, ascorbic acid and -carotene than the spinach leaf. However, no significant (p>0.05) differences were found in nutritional composition and mineral content between the chaya species, except minor differences in the relative composition of fatty acids, protein and amino acids. Cooking of chaya leaves slightly reduced nutritional composition of both chaya species. Cooking is essential prior to consumption to inactivate the toxic hydrocyanic glycosides present in chaya leaves. Based on the results of this study, the edible chaya leaves may be good dietary sources of minerals (Ca, K and Fe) and vitamins (ascorbic acid and -carotene).  相似文献   

19.
The effects of natural compounds, vitamin C and quercetin, present in fruitsand vegetables, on the DNA damaging activity of a food carcinogen N-methyl-N-nitro-N-nitrosoguanidine (MNNG) were examinedusing the comet assay. Vitamin C, at a concentration of 50 M,inhibited MNNG-induced DNA damage in human lymphocytes. Quercetin,up to a concentration of 10 M, increased the extent of DNA damage,but at concentrations above 10 M decreased damage below controlvalues. Furthermore, quercetin had a strong antioxidant activity againstoxidative damage evoked by H2O2 at 10 M. The resultsobtained suggest that vitamin C and quercetin may have anti- orpro-oxidative properties depending on the state of the cell.  相似文献   

20.
Weanling male, Wistar rats (40 per diet) were maintained on 15 diets which provided 4 graded trypsin inhibitor (TI) levels (93, 215, 337, and 577 mg/100g diet) repeated at 3 levels of protein (10%, 20%, and 30%). Raw and heated (toasted) soy flour provided 10% protein in the diet, while casein was added to increase the protein level to 20% and 30%. Three diets containing only casein as the protein source, at 10%, 20%, and 30% were included. Histologic changes occurring in the pancreas were evaluated in approximately 5 rats from each diet at 3 month intervals, beginning at 6 months, for 22 months. Criteria for the diagnosis of the observed histologic changes in the pancreas are discussed. Ultrastructure of the endocrine cells in the gastrointestinal mucosa was also examined.Pancreatic acinar cell density, as determined morphometrically, was reduced throughout the study in rats fed the 577 mg TI/100 g diet, indicating hypertrophy at the cellular level. Nodular hyperplasia was observed in the first sacrifice group at 6 months. Incidence of the lesion was positively related to both time of exposure and level of dietary TI. Acinar adenoma was first observed at 18 months and was most prevalent in rats fed the highest concentration of TI.Endocrine cells of the duodenal mucosa which contain cholecystokinin (so-called I cells) contained a denser population of secretory granules in animals fed the high TI diet compared with I cells from control animals, leading to the speculation that production and secretion of cytoplasmic hormones was increased in TI treated rats.Reference to a company and/or product named by the Department is only for purposes of information and does not imply approval or recommendation of the product to the exclusion of others which may also be suitable.  相似文献   

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