The study of creating and transforming okra as alternative glue aims to prove that there are other resources from nature that can be derived of in making natural glue/adhesive. It can be valuable to those whose necessities are some materials as well as school supplies in school for making such paperwork. It is beneficial to those who want to be thrifty in buying materials for them to save money since this study can conduct in home as well as its materials and ingredients needed could be found at home. Its mucilaginous properties are used as thickening agent for food particularly in soups. The upper part of the okra pods are commonly remove or cut and thrown prior to cooking. This part of okra pod also contains mucilage which gives its slimy characteristic. This mucilage has a good potential to be alternative glue. (University of Sto. Tomas Department of Medical Technology).
The researcher conducted its experimentation by extracting the mucilage of the okra by heating it over the pan and sieves it for its mucilage to be extracted and separated. From that, it will be followed by mixing other ingredients in quantitative measures to give importance of the exact amount of substance to be mixed to extract and to avoid wasting ingredients. The ingredients are particularly the okra mucilage (extract), water, and flour. Through the process of mixing and sieving, its contents will be mix to each other and form a new substance that can be as alternative glue.
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Based on the experimentations, the researcher made different set up to test where is the best set up that represent the exact amount of substance in a mixture. From that, the researcher analyzes the set up by comparing its outcomes due from experimentation and explains the facts and information with the aid of tables and graphs. The researcher can say that based on findings, okra as alternative glue is effective even though it did not actually match the same appearance and texture since the ordinary glue that we bought from stores are synthetic while in the case of this study, it is a natural glue. They recommended the product to some students to their community to use it for their paperwork in school as well as their projects.
Commonly, as students, there are many obligations that should participate particularly in paper works. For instance, there are paper works that should need some materials to make work easier. One of those materials is glue. Glue can be bought on some stores costs Php 10-12. But for some students, they cannot afford such materials in terms that they lack financial needs. The researcher conducted this study to promote an alternative way and to highlight the potential of other things in making a product. Gluekra: Okra (Abelmoschus esculentus) as alternative Glue shows up the alternative way on making glue with used of okra. This study focuses on the potential of okra as renewable product that is significant for purposes.
A. Background of the study
Lady’s finger (Abelmoschus esculentus) or “Okra” is commonly known here in the Philippines as a green finger-shape like fruit. It is one of the many plants which contain mucilage. It was proven according to University of Sto. Tomas Department of Medical Technology that it is widely dominated in tropical regions around the world. Its mucilaginous properties are used as thickening agent for food particularly in soups. The upper part of the okra pods are commonly remove or cut and thrown prior to cooking. This part of okra pod also contains mucilage which gives its slimy characteristic. This mucilage has a good potential to be alternative glue. (University of Sto. Tomas Department of Medical Technology) By extracting the mucilage inside the through boiling, separating, and filtration processes, it possibly releases its mucilage which can be derived in making glue.
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The researcher prepared substance like flour and water to make its ability more effective specifically to its ability to stick papers or other object to paper. On the other hand, glue has contributed in making such things easier particularly to those students making their projects or some activities in school. They were spending money in buying glue instead of gaining savings for other purposes. In that case, they should need alternative way to avoid spending a lot in buying school materials. Due to prior basis of related studies and conceptual experimentation of the researcher to this study, it would result to a comprehensive, long lasting, cheaper but good quality and useful glue for students and other individual.
B. Statement of the problem
* Is it possible that okra can be alternative glue? How?
* How can the mucilage be extracted outside the okra?
* How long can the “gluekra” stick to the paper and other object that can stick to paper?
It is possible that okra can transform as alternative glue. By extracting mucilage of it, that has the ability to produce a sticky texture as glue. By heating the upper part sliced okra, it extracts its mucilage to produce sticky substance. Since this project aims to make glue from okra, it will stick as long as other glue can.
D. Significance of the study
This outcome that follow significantly useful in such that it helps particularly to those students who can’t afford buying glue since the commonly price of it is Php 10-12. It is important for the farmer having plantation of okra to improve their productivity and profitability that they can gain especially that they have ideas about the importance of okra. For ordinary people they can use it for unexpected troubles regarding on pasting their materials or creating a hand-on project. Since glue is universally known as use to paste things it should be needed alternative way to improve not only the product but also the source of the product that being derived. On the other hand, it also applies in such aspects regarding as a source of income or having additional information about the potential of okra.
Source F shows figures for food rationing. What does this tell us about the war time supply of food Source F tells us what was the typical weekly food rations offered to everyone. The source shows us what foods were available at that time. On the list there seem to be that daily products are in short supply this suggests that the farmers in britain would not have had a good year for produce and ...
E. Scopes and Limitations
The said study focuses on the effectiveness of okra mucilage to become glue due to its sticky characteristics. The processing of this study occurs in Antipolo National High School for the verification of the effectiveness of this study. It scopes the date conducted July 6, 2012 and ends within this school year 2012-2013. The purpose of this study is to provide cheaper product which is universally used especially by students and other individuals who’s interested of using it or obliged to use. It deals in one fruit which is okra that can be derived to one product also, glue. It highlights the potential of okra as alternative glue. The limitation of the outcome or product can only have one purpose on what the basis of the product is commonly used. Meaning to say, if the glue is only used for pasting it should be in pasting and should not apply for other purposes.
F. Definition of Terms
Glue- a white or colorless liquid substance that has a sticky texture that is use to paste paper works. Mucilage- a part of okra that has sticky substance
Okra- a finger-shape like fruit
REVIEW AND RELATED LITERATURE
The effectiveness of okra as alternative glue have related studies but have different outcome to be overcome compared to this study. To gather further information about okra, the researcher find related studies about it to settle and lessen the questions and problems of the study. It can also help to have justification for qualification of okra as alternative glue. To define the source that is the reason in making this study, here are some reviews of information:
A. Information about Okra Mucilage
Plant mucilage is found in almost all classes of plants, usually in very small amount. Mucilage and gums are water soluble polysaccharides found in a widespread number of plants and also in some microorganisms. It has different purposes ranging from water storage and seed germination in plants to membrane thickener and food reserve. Okra is one of the many plants which contain mucilage. It is widely distributed in tropical regions around the world.
Its mucilaginous properties are used as thickening agent for food particularly in soups. On the other hand, some people use it for medicinal purposes. The upper part of the okra pods are commonly remove or cut and thrown prior to cooking. This part of okra pod also contains mucilage which gives its slimy characteristic. Okra pods specially when heated produce more sticky mucus. Source: (Department of Medical Technology, University of Sto. Tomas)
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We have included okra mucilage and coconut fibers, things that are relatively cheap and abundant. Up to 75% mucilage was extracted from okra. The coir fibers were cooked for at least three hours, after which the fibers were made fine. Three batches of paper were produced. The first was made up of pure recycled paper; the second of recycled paper and okra mucilage; and the third, recycled paper, okra mucilage, and coconut fibers. (David, et al., 2004-2005) Source: (http://www.investigatoryprojectexample.com/science/wastepaper-and-coir-with-okra-mucilage.html)
Okra is a vegetable that has been cultivated for more than 800 years originating somewhere in present day Ethiopia. It was introduced by Africa to America and has been an important part of the South American diet in the form of stews and gumbos (thick stews).
In the Philippines, okra is used in
the traditional pinakbet and sinigang and to some extent a plain roasted vege; some would eat it raw. It is a significant source of dietary fiber, Vitamin A, and potassium and Vitamin C. The seeds of okra can be dried, roasted, ground and brewed as a substitute for coffee. The ripe seeds can also yield edible oils. The leaves are used as medicinal remedy to reduce swelling and inflammation. This vegetable is rich in dietary fibers that help stabilize blood sugar.
Okra can also help reduce cholesterol by binding along with bile acids which usually carry the toxins which the body should eliminate. The mucilaginous material in the fruit also facilitates the binding. This property is comparable to taking satins. As we know statins are the drugs that doctors prescribe in cases of high cholesterol or high dangerous fat in the blood. This however works in our intestines and virtually eliminating the source of high fat that is already attached with bile salts. (Gemiliano Aligui, 2006) Source: (Research Institute for Tropical Medicine – Assistant Director) The research work aimed to determine the possibility of producing glue and paper from scrap hides. For the production of glue, alum was added to the extract produced from the boiling of scrap hides.
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As for the production of paper, the pulp was not subjected to quantitative test. It was immediately processed into paper by hand papermaking.The glue produced developed into a heterogeneous mixture of a crystalline substance and the liquid which did not exhibit sufficient adhesive properties on wood or paper. On the other hand, the paper produced exhibited a tearing strength (58.0g) within the range of Philippine standards for wrapping paper but was substandard in terms of thickness (35.71 mills) and weight (419.0 kg/15mm).
It did not pass any of the standards for writing paper. (Chin, et. al., 1995) Source: (The Production of glue and paper from scrap hides)
The research study aimed to produce a cheap and environmentfriendly adhesive from D-limonene dissolved Styrofoam. A minor objective was to recycle Styrofoam by reusing waste Styrofoam for the production of the adhesive. D-limonene is an extract from citrus fruits like lemon and is proven to be safe to dissolve polystyrene. Styrofoam, the commercial name for polystyrene is widely used in society. Food packaging is one major source of waste Styrofoam. To prepare the adhesive, used Styrofoam containers were dissolved in D-limonene with different proportions divided into four set-ups. The first and the third treatment were of the same concentration consisting of 5 mL Dlimonene: 2 g Styrofoam, but the third, unlike the first set-up, was boiled. The second and the fourth treatments both had a concentration of 5 mL Dlimonene: 1 g Styrofoam.
The fourth treatment was also boiled. After production, the adhesives were applied on wood blocks to test their holding strength by attaching weights on one side of bound wooden blocks.Five replicates were used for each treatment including the control. The average weight each pair of blocks can carry were subjected to ANOVA tests to determine if adhesive treatments were comparable to the commercial adhesive, Rugby.Results showed that some treatments were as strong as Rugby in terms of holding strength.
But, treatment A had the best holding strength and can be considered an alternative for commercially available adhesives.The group concluded that the first treatment had potential to be an alternative for commercial adhesives. The results of the study showed that there was no significant difference between the first and the control treatments only. Therefore, Styrofoam melted in limonene has the potential to be recycled as an adhesive. (Perez III, et. al., 1996) Source: (D-limonene Dissolved Styrofoam As Adhesive)
Chemistry Investigatory Projects Title: The Effects of Microwaved Water on Plant Growth Problems: 1. What are the factors that make the microwave harmful? 2. What happens to the water (when microwaved) that causes it to affect plant growth? 3. What are the effects of microwaved water on the growth of plants? Hypotheses: 1. The micro wavelength radiation the microwave contains makes it harmful. 2. ...
A study on the potential of using extracts from three easily accessible plants, okra (hibiscus esculentus), kamote leaves (Ipomea batatas), and ginger rhizomes (zingiber officinale) was made. Crude extracts were prepared from each plant sample. Ethanol was used as the solvent for the extracts. The pH of each extract was taken. They were tested in acidic and basic solutions to determine whether or not their initial colors would change. Three sets of thirteen solutions of different pH’s were prepared, one for each extract. Then the extracts were stability of these extracts were also determined. Then the specific pH sensitive substance in the extracts were determined.
The results showed that the okra changed color from cloudy green to yellow at pH 6.8 to 7.15. The ginger was initially red-orange, but becamecloudy in acidic solutions. pH range was 12 to 10. The kamote leaf extract changed form dark red-brown to very dark bluish-green at pH 10-12. The okra extract was found to be the best acid-base indicator among the three, because it showed the most obvious color change at the boundary of acidity and basicity. (Chavez et. al., 1996) Source: (The potential of okra (Hibiscus esculentus), Kamote leaves(Ipomea batatas), and ginger Rhizome (Zingiberofficinale) Extracts as acid-base Indicators This research project, entitled “Determination of the adhesive potential of coconut (cocos nucifera) husk extract,” aimed to extract lignin from coir dust by a method previously used on saw dust and the determine the extract‟s potential as a paper and wood adhesive by employing simplified versions of standard tests.
Coir dust is said to be approximately forty-five percent lignin, a polymer whose basic building blocks are phynel propane monomer, benzene rings attached to three carbon side chain atoms, and which is thought to exhibit adhesive properties. Since lignin is a waste product of the pulp and paper making process, it would be of some significance to verify whether the extract would be used as a glue. The extraction process yielded a light brown, semiviscous sticky liquid which exhibited positive properties in so far as it was able to keep pieces of paper and wood stuck together for more than 24 hours. The rip test and water tests were done using varying concentrations of extract and polvinyl alcohol and showed other properties of an adhesive. (Diokno et. al., 1995) Source: (Determination of the adhesive potential of coconut (cocos nucifera) husk extract) This research is concerned with recycling of styrofoam, scientifically known as a foam polystyrene (FPS), a plastic resin.
Styrofoam was reused as a major material for making an adhesive. Gasoline was used to dissolve the FPS, resulting in a sticky mixture. Five mixtures of FPS-Gasoline were made with the ratios of 11:4, 9:4, 7:4, 5:4, and 1:1 Blocks of wood having the same sizes were used for testing the adhesiveness of the mixtures. Each of the mixture was applied on a clean surface of the block and was left to air dry. Each mixture was tested against the commercially available cement rugby. A test of tension was done, pulling the two blocks which are bonded together by the mixture (receiving load).
Results proved that the adhesive was comparable with the commercially produced RUGBY. It also showed that the mixtures having the ratios greater than 1:1 (FPS-gasoline mass ratio) are much stronger than RUGBY. (Rivera, 1997) Source: (Foam polystyrene-Gasoline Mixture as an Adhesive)
Partial defoliation of okra plants was done on one group at the four week stage and on another group at the six-week old stage. Measurements were taken of fruit weight, fruit diameter, fruit length, number of fruits per plant, plant height, and plant basal stalk diameter.Observations showed that plants defoliated at the four week stage matured earlier than the control group. Qualitative tests showed significant increases in weight yield per plant for those plants defoliated at the four-week stage. However, defoliation at the sixth week was found to have significantly decreased the weight and mean fruit diameter. No significant differences were noticed in plant height and basal stalk diameter. (Aldea, 1996) Source: (The effects of partial defoliation on the yield of okra (Hibiscus esculentus)
The % yield of mucilage from okra fruit was 47.28%. The mucilage was tested using the Xanthroproteic and Ninhydrin tests for aromatic amino acids and free amino acids respectively. Positive results were obtained. The presence of glucose was confirmed by the Benedict’s solution.Several PDA (Potato Dextrose Agar) – mucilage mixtures were prepared using the ratios 0-100, 25-75, 50-50, 75-25, 100-0 percent by volume. These mixtures were inoculated with S. cerevisiea and growth was observed after 24 hours of incubation at 28˚C. Growth was observed in all the replicates of the treatments. Thus the control and the experimental media had no difference between them in terms of supporting yeast growth.To quantify the results of the above observation, nutrient Broth (NB) –mucilage mixtures were used at the same ratios as above and inoculated with 0.1 ml of a prepared inoculum containing 3.1 x 104yeast cells. =Yeast count was performed using a hemacytometer after 24 hours. The means of the cell count and their standard deviations were also calculated.
A 2 sample t0test was performed (control against experimental treatment) resulting in the acceptance of the Ho. The experimental and control media were not significantly different in terms of capacity to support the growth of the yeast cells. A 1 sample t-test was performed to investigate the significant increase in the number of yeast cells after 24 hours in the treatments. Negative results were obtained for media treatment media 0-100 and 100-0 while significant differences were obtained for 25-75 at = 0.01 and for 50-50 and 75-25 at = 0.05. (De Castro, 1996) Source: (The potential of Okra (Hibiscus esculentus) Mucilage as a culture medium for Yeast (Saccharomyces cerevisiea) Foreign Related Studies
For the development of salinity tolerant okra breeding material, studies were undertaken on the assessment of genetic variability for salinity tolerance in the available okra germplasm at the seedling stage, assessment of genetic diversity with molecular makers, responses of the selected tolerant and non-tolerant genotypes to salinity stress during ontogeny of the whole plant in summer and spring seasons and genetic basis of variation for salinity tolerance. Substantial variation appeared to exist in okra for salinity tolerance at the seedling stage. The 80 mM NaCl concentration was found suitable for discriminating tolerant and non tolerant okra genotypes because many genotypes failed to germinate at higher NaCl concentrations and maximum variation among the genotypes appeared at this concentration.The pooled ranking of the genotypes, based on their individual rankings for each trait in single NaCl concentration appeared effective for selecting tolerant genotypes.
Twenty RAPD primers were used to analyze the genetic diversity among the okra germplasm, which showed considerable polymorphism in the okra genotypes. The cluster analysis divided the 39 okra genotypes into seven main clusters with maximum similarity of 82.88% between Sabzpari 2001 and Acc.No.019221. The genotypes selected at the seedling stage for salinity tolerance maintained their tolerance to NaCl during the ontogeny of whole plant. This suggested that the screening of the germplasm accessions and breeding material for salt tolerance at the seedling stage is effective, at least for initial selection.
The NCM II analysis was carried out to estimate components of genetic variation in okra genotypes. The inheritance of salinity tolerance in okra at seedling stage appeared to be governed by both additive and non additive genetic effects. The additive effects were predominant and narrow sense heritability was moderate. It is concluded that the genetic variation for tolerance to NaCl salinity existed among the okra genotypes, which had considerable heritable component and, therefore, genetic improvement of okra genotypes for salinity tolerance through breeding and recurrent selection is possible. (IKARM-UL-HAQ, 2009)
Source: Genetic Basis of Variation for Salinity Tolerance in Okra (Abelmoschus esculentus L.) (2009, University of Agriculture Faisalabad, Pakistan)
Okra fruits and baobab leaves are just two examples of foods used to give a mucilagi- nous quality to West African food dishes. The mucilages were extracted from both foods and purified. Preliminary studies have been conducted t o characterise the mucilages chemically, as well as study their viscous behaviour in relation to their use in West African dishes. Both mucilages are acidic polysaccharides with associated protein and minerals. Neither the quantity of protein nor minerals were significantly reduced during purification. The protein was not separated from the polysaccharide by either gel chromatography or disc electrophoresis. They attain maximum viscosity in the neutral p H range. However, the mucilage solutions are not stable to heat and lose much of their viscosity when heated. (Mark L. et al., 1976)
Source: (Studies on the Mucilages Extracted from Okra Fruits (Hibiscus esculentus L.) and Baobab Leaves (Adansonia digitata L.) Department of Nutrition and Food Science, University of Ghana, Legon, Ghana (Manuscript received 19 November 1976)
West African Okra [Abelmoschus caillei (A. Chev) Stevels] is a multipurpose annual, biennal herb sometime perennial woody crop plant common in the humid West African subcontinent. It is produced in traditional agriculture especially when other vegetables are not in season and an important cash crop in the local economy. This study is aimed at generating information and documenting the ethnobotany of A. caillei via the indigenous knowledge among tribes of Delta, Edo and Ondo States of Nigeria).
Primary information was collected from randomly selected respondents through survey using structured questionnaires and guided walks within 54 sites. A 18-87 years old. Of this number, 259 (48%) were males and 281 (52%) females. Nine ethnic tribes were recorded in the 3 States.
The tribes varied in their socio-cultural and economic characteristics and local knowledge about the crop. One-two local names of the crop were recorded with one related “type”. Traditional uses of the crop include food (100%) and nonfood purposes. The information from non-food uses include medicine (27%), myth/religion (32%), soil fertility indicate (19%), rainy season indicator (8%), dry season/harvest time indicator (100%), fuel (15%) and sponge (11%).
These sets of information indicate that the crop plant is of prime importance in the area. ( Osawaru M. E., Dania-Ogbe, F. M, 2010) Source: (Ethnobotanical Studies of West Africa Okra [Abelmoschus caillei (A. chev) Stevels] from some Tribes of West Nigeria (Science World Journal, 2010) Ten selected genetically diverse okra strains were evaluated in one location for two years in Yola Nigeria. The objective was to study the extent of variability and relationship between various economically important traits for the purpose of genetic improvement. The trial was laid out in a Randomized Complete Block Design (RCBD), with three replications.
The data collected included, plant height, number of branches per plant, days to 50 % flowering, days to 95 % maturity, number of fruits per plant, fruit diameter and yield per plot. Analysis of variance and other genetic analyses such as genotypic and phenotypic coe icient of variation and genetic advance were performed. The results obtained showed variation in all the cultivars and characters measured such as fruit diameter (1.17**), days to 95 % maturity (374.76**), days to 50 % flowering (422.98**), number of fruit per plant (54.13**).
Genotypic coe icient of correlation showed more significant relationship between the pairs of characters, meaning that, these characters are more related genotypically. The characters, which showed high broad sense heritability and high genetic advance after selection respectively, included fruit diameter (18 % and 61 %) and number of branches per plant (96 % and 41 %).
These characters are all under additive gene e ects. In conclusion, therefore; genetic variation exists among the cultivars in all characters studied. However, Ex-Wuro Sarki showed greater potential for yielding ability while ExSangere I, although, a poor yielder, is a good material for earliness. Therefore hybridization between these two could produce a high yielding and early F1 (hybrid) variety. (Bello, D, et al., 2006) Source: (Variability and correlation studies in okra (Abelmoschu esculentus L. Moench) (Journal of Sustainable Development in Agriculture and Environment, 2006) Okra is one of the important vegetables grown in India during both summer and rainy seasons. This is an often cross-pollinated crop showing 4–19% cross pollination. Emasculation and pollination processes are easier due to large flower and monoadelphous stamens.
This enables the breeder to exploit the hybrid vigor through manual hybridization. Considering the importance of bhindi, an investigation was carried out with five lines and two testers with three replications at Agricultural College and Research Institute, Madurai during 2001–2002 in order to determine the extent to which the heterosis is manifested. The observations recorded were plant height, days to first flowering, number of nodes/plant, fruit length, fruit girth, number of fruits/plant, single fruit weight, number of seeds/fruit, 100 seed weight, crude fibre content, protein content, and yield/plant.
The results revealed highly significant differences for all the characters among the parent and genotypes studied indicating wider range of variability. Among all the crosses evaluated, the cross combination IC 169340 x IC 112475 exhibited highest heterosis for all the characters studied. (K. Shoba, S. Mariappan, 2000) Source: (Heterosis Study in Okra (ABELMOSCHUS ESCULENTUS (L.) MOENCH) for some other Biometrical Traits) ( I International Conference on Indigenous Vegetables and Legumes. Prospectus for Fighting Poverty, Hunger and Malnutrition, 2000)
Okra fruits, Taro tubers, Jew’s mellow leaves and Fenugreek seeds are commonly used in Egypt to prepare popular diets with desired slimy consistency. The mucilages were extracted and preliminary studies conducted to characterise them physically. The pH values of a 1% solution of the mucilages varied from 6·9-7·5 for Okra and Taro, 7·1–7·8 for Jew’s mellow, and 5·9-6 for Fenugreek, depending upon extraction conditions. The highest viscosity was observed in Okrasolutions, followed by Fenugreek, Jew’s mellow and Taro mucilages. Okra and Jew’s mellow mucilages are acidic polysaccharides which contain higher amounts of ash than the Taro and Fenugreek mucilages which are neutral polysaccharides. All mucilages are associated with protein.
Gel chromatography indicated strong interaction of protein with the polysaccharide. The acid hydrolysis of the mucilages followed by paper chromatography revealed that all mucilages contain methyl pentose, glucose, galactose, and fructose, in different proportions. Taro and Fenugreek mucilages are free of rhamnose. All mucilages are devoid of arabinose and mannose except Fenugreek which contained these two sugars. (El-Sebaiy, 2003) Source: (Preliminary studies on the mucilages extracted from Okra fruits, Taro tubers, Jew’s mellow leaves and Fenugreek seeds (Food Technology Department, Kafr El-Shiekh Faculty of Agriculture, Tanta University, Egypt, 2003)
Polysaccharide extracts were prepared from two traditional food thickeners with extensive domestic use in central and western parts of Africa: okra (Hibiscus esculentis L.) and the seed kernel from ‘dika nut’ (Irvingia gabonensis).
Both demonstrated typical polyelectrolyte behaviour in solution, and were therefore studied under fixed ionic conditions (0.1 M NaCl), yielding intrinsic viscosities of [η] = 7.6 dl g−1 for okra and [η] = 4.4 dl g−1 for dika. Concentrated solutions gave mechanical spectra typical of entangled networks, with close Cox-Merz superposition of η(ω) and η(γ).
The variation of ‘zero-shear’ specific viscosity with degree of space-occupancy (c[η]) was also broadly similar to the general form observed for most disordered polysaccharides, but with greater separation of c∗ and c∗∗ and steeper slope of log ηsp vs. log c above c∗(~4.0 for okra and ~4.6 for dika, in comparison with the usual value of ~3.3).
As found for normal disordered polysaccharides, the shear-thinning behaviour of dika gum could be reduced to a single ‘master-curve’ for all concentrations above c∗∗, but the absolute value of the terminal slope of log (η-ηs) vs. log ⋗g was unusually low (~0.58, in comparison with the normal value of ~0.76).
Terminal slopes for okra gum were also unusually low, and varied systematically with polymer concentration. These departures from normal solution properties are tentatively ascribed to compact macromolecular structures, coupled, in the case of okra gum, with a strong tendency to self-association. (R. Ndjouenkeu, et al., 2000)
Source: (Rheology of okra (Hibiscus esculentus L.) and dika nut (Irvingia gabonensis) polysaccharides (Department of Food Technology, University of Ibadan, Ibadan, Nigeria, 2000)
Freshly harvested okra fruits were blanched in boiling water (with or without 0.2% sodium metablsulphite salt) and the effect of this treatment, dehydration methods and temperature on certain characteristics of okra investigated. Blanching resulted in the slight decrease in carbohydrate, fat, ash, colour components, ascorbic acid and viscosity. Besides this initial loss, blanching in sulphite solution led to the retention of more of the colour components and ascorbic acid during dehydration. All dehydrated okra samples had higher contents of carbohydrate, fat and ash but lesser contents of protein and ascorbic acid than fresh okra.
Fresh okra fruits, on the other hand, had higher content of the colour pigments and were more viscous than all dehydrated products. Samples blanched prior to dehydration retained more of the colour components but were less viscous than unblanched samples. Vacuum dehydrated samples retained more ascorbic acid, colour pigment and mucilage at each of the dehydration temperatures than those from a hot air oven. High dehydration temperatures had negative effect on the colour, ascorbic acid and viscosity of okra. (U. E. Inyang and C. I. Ike, 1998)
Source: (Effect of blanching, dehydration method and temperature on the ascorbic acid, colour, sliminess and other constituents of okra fruit (Department of Food Science & Technology, University of Agriculture, 1998)
The European community has commissioned a programme for the development of non-food plants with economic potential (project AIR 3-CT-1236).
In this project, five varieties of okra (Veludo, Bogiatou, Pyleas, Levadias and Kilkis) were cultivated in 1994 on an experimental plot in the south-west of France (near Mont de Marsan).
Three varieties (Veludo, Pyles and Kilkis) were also cultivated in 1995 in a Mediterranean area near Narbonne (France).
The plants appeared to be suited to the wet climate of Mont de Marsan and the hotter, drier climate of Narbonne. Contents in hemicellulose, cellulose and lignin were determined in all the parts of the plant.
Concerning the hemicellulose content of the stem, the richest varieties are Veludo and Bogiatou (17%); Veludo has the highest content of hemicellulose in the dry, mature fruits (19%).
Concerning the seed oil content, Levadias and Pyleas had a high content of palmitic acid (28%) and Kilkis a high content of linoleic acid (52%).
Oil content was 15–19% in all varieties. The Bogiatou and Levadias varieties produced a cake containing more than 30% proteins. The yield in oil, the quality of its proteins and the use of the stem in paper-making, indicate that okra has economic potential for cultivation on set aside acreage in this part of Europe. (M. Camciuc, et al., 1998)