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Open Access
Book part
Publication date: 4 May 2018

Suhendrayatna, Muhammad Zaki, Annisa Delima Habdani Harahap and Fitriani Verantika

Purpose – In this study, the possibility of the application of rice husks for adsorbing Mn(II) ion in the water phase has been studied.Design/Methodology/Approach

Abstract

Purpose – In this study, the possibility of the application of rice husks for adsorbing Mn(II) ion in the water phase has been studied.

Design/Methodology/Approach – Experimental studies have been initiated by preparing activated carbon from rice husks. The activation of rice husks was done using both physical and chemical treatment methods through heating at 110 °C and washing with citric acid activator at 0.2 M, 0.4 M, and 0.6 M. The adsorption tests were conducted as two part tests: preliminary and primary. The preliminary test was conducted to choose the best condition of four independent variables, i.e., contact time (0–120 minutes), activator concentrations (0.2, 0.4, and 0.6 M), initial Mn(II) concentrations (10, 20, 50, 100, 200, and 400 mg/L), and adsorption temperatures (30, 47, and 67 °C).

Findings – By identifying the substituted groups using Fourier Transform Infrared Spectroscopy after activation with citric acid, it was found that the highest transmittance percentage was present in activated carbon with 0.2 M of citric acid. The best adsorption capacity and efficiency was 13.87 mg/g and 79.60%, respectively, which were obtained at 200 mg/L initial concentration with a 0.2 M citric acid concentration for 120 min contact time at 47 °C. These results lead to a conclusion that rice husks after activation with citric acid can be applied as an adsorbent for Mn(II) adsorption in the water phase.

Research Limitations/Implications – The activated carbon produced was only applicable for the adsorption of Mn(II) ions from the water phase, but not applicable for the adsorption of other heavy metals ions.

Practical Implications – Rice husks were potentially prepared as an adsorbent for Mn(II) ion adsorption in the water phase that was low cost, environmental friendly, and easy to prepare.

Originality/Value – Activated carbon prepared from biomass was mostly carried out using acids at high concentrations while the study was conducted using weak acids (citric acid) at low concentrations.

Details

Proceedings of MICoMS 2017
Type: Book
ISBN:

Keywords

Article
Publication date: 1 August 1997

S.A. Abdel‐Hafiz, F.F. El‐Sisi, M. Helmy and A. Hebeish

Samples of loomstate cotton fabric were first treated with aqueous potassium permanganate solution at different concentrations in the presence of a non‐ionic wetting…

302

Abstract

Samples of loomstate cotton fabric were first treated with aqueous potassium permanganate solution at different concentrations in the presence of a non‐ionic wetting agent. The samples were then washed and treated using solutions containing methacrylic acid, wetting agent and acid or basic dye along with citric acid of different concentrations at different temperatures for different times. The critical properties of the fabric such as graft yield (expressed as carboxyl content m.eq/100g cellulose), colour strength before and after soaping and percentage loss in colour strength due to soaping were found to depend on the concentrations of KMnO4, citric acid and methacrylic acid as well as duration of the treatment. Based on the results obtained, treating formulations consisting of KMnO4 (0.1g/l), citric acid (0.1g/l), methacrylic acid (50 per cent), dye (1 per cent) and wetting agent (2g/l) was considered appropriate for concurrent grafting and dyeing of the said fabrics provided that the treatment was carried out at 90°C for 60 minutes.

Details

Pigment & Resin Technology, vol. 26 no. 4
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 1 July 1922

We publish below a Circular which has been issued by the Ministry of Health (Circular No. 325), addressed to the Town Clerks of the various Councils, urging the Councils…

Abstract

We publish below a Circular which has been issued by the Ministry of Health (Circular No. 325), addressed to the Town Clerks of the various Councils, urging the Councils not to take actions against vendors of adulterated milk except in cases where it has been proved by repeated sampling that the milk from such vendors is consistently below the legal standard. A more stupid and damaging circular it is not possible to conceive, and the matter is one which calls for very strong representations being made by the Councils throughout the country. The effect of adopting the recommendations of the circular in question would be to practically stultify the Food and Drugs Acts in so far as the sale of adulterated milk is concerned, and it would further encourage the dairy farmer to keep certain breeds of cows which are well known for the very large quantity of milk which they produce of poor quality. The mixed milk from a properly selected herd of cows which are properly fed will never fall below the extremely lenient standard fixed by the Board of Agriculture. Whether the production of inferior or adulterated milk is due to the extraction of cream, the addition of water, improper feeding or improper selection of the cows, is of no moment to the consumer, the motive for the adoption of any of these methods is pecuniary benefit. If the desire of the Ministry of Health is to encourage adulteration and sophistication of food and to bring to nought what little protection is afforded to the consumer by the administration of the Sale of Food and Drugs Acts, a more effective Circular could hardly have been issued.

Details

British Food Journal, vol. 24 no. 7
Type: Research Article
ISSN: 0007-070X

Article
Publication date: 25 May 2010

F.V. Adams, P.A. Olubambi, J.H. Potgieter and J. Van Der Merwe

The purpose of this paper is to supplement the scant previous investigations on the corrosion behaviour of 2205 and 2507 duplex stainless steels in selected organic acids

Abstract

Purpose

The purpose of this paper is to supplement the scant previous investigations on the corrosion behaviour of 2205 and 2507 duplex stainless steels in selected organic acids containing chloride additions.

Design/methodology/approach

Microstructural examination of the alloys was first carried out, after which the corrosion behaviour of the alloys in citric, oxalic, formic and acetic acids containing chloride additions at varying temperatures was studied using electrochemical techniques.

Findings

The alloy 2507 material had a larger grain size than did the alloy 2205 sample. The corrosion resistances of the alloys generally are highest in acetic acids and lowest in citric acid. The addition of chloride had a pronounced effect on their corrosion resistance. Alloy 2507 generally exhibited higher corrosion resistance in all of the acids than alloy 2205, with the exception of acetic acid at room temperature. The 50:50 ratio of ferrite to austenite composition, as revealed by phase compositional analysis, indicated no significant possibility for galvanic corrosion between the phases. This suggests that the corrosion behaviour of the alloys is controlled by their grain sizes and chemical compositions.

Originality/value

Although the corrosion behaviour of duplex stainless steels in some organic acid media has been reported, this investigation covers the major organic acids not previously reported. Since in real industrial systems a mixture of both organic and minerals acids/salts may typically exist, investigations of the combined effect of chloride ions with the organic acids reported in this paper typify real industrial operations. The paper thus provides a basis for material selection for the application of 2205 and 2507 in industrial systems where organic acids are mostly used.

Details

Anti-Corrosion Methods and Materials, vol. 57 no. 3
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 1 April 1995

M. Nasta and H.C. Peebles

A good solder flux must simultaneously perform a number of important functions. It must promote thermal transfer to the area of the solder joint, enhance wetting of the…

Abstract

A good solder flux must simultaneously perform a number of important functions. It must promote thermal transfer to the area of the solder joint, enhance wetting of the solder on the base metal, and prevent oxidation of the metal surfaces at soldering temperatures. However, its primary task is to remove the tarnish layer from the metal joint that is about to be soldered. Despite the fact that the process of soldering electronic devices is a part of a multi‐billion dollar industry, the actual chemical reactions that occur during this cleaning process are not well documented. In the case of organic acid or water‐soluble fluxes, the flux reactions can be modelled by considering the interactions at the metal/metal oxide/electrolyte solution interface. Although such modelling systems have not frequently been applied to the behaviour of solder and fluxes, they are common for a number of other closely related chemical systems which are of practical interest, e.g., passivation layers on metals, electrochemical cells and metal oxide semiconductors. There are two types of reactions that can occur at the oxide/solution interface: acid‐base reactions and oxidation‐reduction reactions. The factors which affect the reaction rates and mechanisms are such variables as the structure of the metal oxide, temperature, pH, concentration of the electrolyte, and the chemical nature of the solute and solvent. By combining information about flux behaviour with available models of surface reactions, it should be possible to develop the theory of the flux reactions and to gain a better understanding of the factors which control the process.

Details

Circuit World, vol. 21 no. 4
Type: Research Article
ISSN: 0305-6120

Article
Publication date: 17 September 2019

Dhamawatee Harnarun Etwaroo, Viswen Armoogum, Dayawatee Goburdhun, Arvind Ruggoo, Pooja Dookheea, Henna Thorul and Fahilah Zainab Noormahomed

The purpose of this paper is to determine the level of food additives, caffeine and total sugars in locally manufactured beverages in Mauritius and ascertain their…

233

Abstract

Purpose

The purpose of this paper is to determine the level of food additives, caffeine and total sugars in locally manufactured beverages in Mauritius and ascertain their compliance with national and international norms.

Design/methodology/approach

In total, 48 beverages: 21 soft drinks, 14 ice teas, 5 fruit drinks, 5 nonalcoholic sparkling drinks and 3 tonic waters were analysed for the level of sweeteners (aspartame, acesulfame K and saccharin), preservatives (benzoic and sorbic acid), colours (tartrazine, sunset yellow, quinoline yellow, allura red, amaranth, ponceau 4R, carmoisine, erythrosine, brilliant blue, green S and patent blue), citric acid, caffeine and total sugars. High-performance liquid chromatography methods used to quantify the levels of total sugars, caffeine and additives were validated against parameters such as linearity, recovery, accuracy, precision and limit of quantification.

Findings

Out of 48 beverages, 13 contained at least one sweetener. The most frequently used sweeteners were acesulfame K and aspartame. Benzoic acid was present in 27 samples (42.32–168.03 mg/L). Sorbic acid was present in 14 beverages (13.01–180.38 mg/L). Citric acid (0.7–4 g/L) was present in all the 48 beverages, while caffeine was present in 20 samples in the range of 14.01–129.42 mg/L. Nine samples contained at least one artificial colour and the most frequently used colours were tartrazine, sunset yellow, brilliant blue and carmoisine. The average level of total sugars present in the beverages was 10 g/100 ml. The validation parameters obtained showed evidence for method suitability.

Research limitations/implications

Beverages sold by individuals on the street, small restaurants and markets were not analysed.

Originality/value

This study provides an overview of the chemical composition of soft drinks and their compliance with Food Regulations. It also paves the way to investigate weaknesses, knowledge, attitudes and practices of local manufacturers, which leads to non-adherence to Regulations regarding food additives.

Details

British Food Journal, vol. 121 no. 11
Type: Research Article
ISSN: 0007-070X

Keywords

Article
Publication date: 2 March 2015

S.V. Lee, A.N. Hadi, Z.H.Z. Zainal Abidin, N.A. Mazni, N.A. Halim, R. Usop, H.C. Hassan, S.R. Majid and A.K. Arof

The purpose of this paper is to observe the colour and thermal stability of natural red dye consisting of anthocyanin with addition of different aqueous acids and applied…

Abstract

Purpose

The purpose of this paper is to observe the colour and thermal stability of natural red dye consisting of anthocyanin with addition of different aqueous acids and applied as coating films.

Design/methodology/approach

The natural red dye was extracted from Hibiscus sabdariffa L. (roselle) flowers and mixed with 1 per cent hydrochloric acid, 5 per cent acetic acid, 5 per cent citric acid and 5 per cent oxalic acid. All the dye samples were exposed to heat and UV-B to observe the colour stability by calculating the half-life and rate of reaction. In coating film application, each of the dye samples was mixed with 25 wt% of poly(vinyl alcohol) (PVA) and applied on to a glass substrate. The coating samples’ colour stability was observed by using CIE L*a*b* colour space coordinates. The coating films’ weight loss stability against temperature was observed by using thermogravimetric analysis.

Findings

Addition of hydrochloric acid enhances the thermal and UV stability of the anthocyanin natural dye. This can be observed from the calculation of the half-life of the dye. The half-life values for the thermal and UV stability studies were 1,155 hours and 210 hours, respectively. In coating films, the sample with addition of acetic acid showed the highest colour stability with colour difference (ΔE*) value 8.95.

Research limitations/implications

The coating films developed in this work are not suitable to be applied on metal substrates due to the presence of water, which can contribute to the corrosion formation.

Practical implications

The coating films developed in this work are suitable for washable coating application. In other words, they are non-permanent coatings applied on a glass substrate.

Originality/value

Development of water-based coatings from PVA binder with anthocyanin colourant is introduced in this study.

Details

Pigment & Resin Technology, vol. 44 no. 2
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 2 November 2021

Nan Sun, Beibei Tan, Bolun Sun, Jinjie Zhang, Chao Li and Wenge Yang

Sargassum fusiforme is a popular edible seaweed in coastal cities of China that contains diverse nutrients including iodine. Cooking is an effective way to improve food…

Abstract

Purpose

Sargassum fusiforme is a popular edible seaweed in coastal cities of China that contains diverse nutrients including iodine. Cooking is an effective way to improve food safety, but it can alter both the contents of elements along with speciation and bioavailability. Three common cooking methods, the soaking, steaming and boiling, were evaluated for their effects on the protein structures, protein digestibility, iodine content and iodine bioavailability of S. fusiforme.

Design/methodology/approach

Fourier transform infrared spectroscopy was used to study the structural changes of protein, and an in vitro digestion/Caco-2 cell culture system was used to evaluate the digestibility of protein, bioaccessibility and bioavailability of iodine.

Findings

Boiling and steaming altered the protein secondary structure demonstrated by increased a-helix and random coil and decreased β-sheet, which improved the in vitro protein digestibility. Iodine content was reduced by cooking, with the highest loss observed after boiling, followed by soaking and steaming, while it was found that both bioaccessibility and cellular uptake of iodine were significantly elevated by boiling and steaming using an in vitro digestion/Caco-2 cell culture system. The presence of ascorbic acid, citric acid or tyrosine was beneficial for the iodine absorption, while oxalic acid and phytic acid hindered the iodine bioavailability.

Originality/value

The present finding suggested that cooking was conducive to the digestion and absorption of iodine in S. fusiforme. In addition, different dietary factors could have a certain impact on the absorption of iodine. Results of the study are essential for improving the application value of S. fusiforme to ensure reasonable consumption of seaweeds.

Details

British Food Journal, vol. 124 no. 9
Type: Research Article
ISSN: 0007-070X

Keywords

Article
Publication date: 9 November 2018

Rita Mansour

The purpose of this paper was to determine and compare nutritional composition of different parts of citrus fruits, namely, Citrus aurantium (peel: albedo, flavedo and…

Abstract

Purpose

The purpose of this paper was to determine and compare nutritional composition of different parts of citrus fruits, namely, Citrus aurantium (peel: albedo, flavedo and pulp: juice, pomace) . This study was conducted through three stages of fruit maturity (green, yellow and orange). Total polyphenols, flavonoids, β-carotene, total chlorophyll, ascorbic acid, acidity, total soluble solid and the minerals (Ca, Mg, Zn, Na, K, Fe, Mn Cu) were evaluated. Moreover, the relationship between the total polyphenol, flavonoids and the antioxidant activity was determined.

Design/methodology/approach

Total polyphenols were determined by the Folin-Ciocalteu method. Flavonoids were assessed by the aluminum chloride colorimetric method. Ca, Mg, Zn, Fe, Mn and Cu were measured using an atomic absorption spectrophotometer. K and Na contents were determined by using a flame photometer. Other nutritional composition was determined by volumetric method.

Findings

The result showed that the concentrations of antioxidants, total polyphenols, flavonoids, vitamin C, total chlorophyll, total acidity and antioxidant activity (DPPH%) decreased during the maturity of fruit while the value of pH and β-carotene increases. In addition, the concentrations of the most minerals decreased through the maturation of fruit except Na. Anova statistical analysis of all the studied chemical variables was shown significant differences between all the samples. The pH, total soluble solids, β-caroteniod: orange juice had the highest average while green juice had the lowest. Ascorbic acid, total acidity, total chlorophyll: green juice had the highest average while orange juice has the lowest. Total phenol, K, Mg, Fe, Cu, Mn: green flavedo had the highest average while orange juice had the lowest. Flavonoid, antioxidant activity (DPPH%), Ca, Zn: green albedo had the highest average while orange juice had the lowest. Na: orange flavedo had the highest average while green juice had the lowest. The correlations between total polyphenol, flavonoid and antioxidant capacity were significantly higher (R = 0.935 and 0.960, respectively).

Originality/value

The stage of maturity affects nutritional composition in Citrus aurantium fruits (C. aurantium) peel and pulp, where some minerals of composition increased and others decreased, according to the results. This is the first study on comparing the nutritional composition of pulp: juice, pomace and peel: albedo, flavedo of Citrus aurantium L. during maturity in Syria, and it was also not found in previous works.

Details

Nutrition & Food Science, vol. 49 no. 2
Type: Research Article
ISSN: 0034-6659

Keywords

Article
Publication date: 30 October 2018

Tanya L. Swer, Komal Chauhan, Prodyut K. Paul, C. Mukhim, Khalid Bashir and Rachna Sehrawat

An upsurge in health and environmental concerns over the use of synthetic color has made the development of color from cheap and easily available natural sources, namely…

Abstract

Purpose

An upsurge in health and environmental concerns over the use of synthetic color has made the development of color from cheap and easily available natural sources, namely, plants, animals, micro-organisms and algae as indispensable. This study aims to extract anthocyanins, an important natural plant pigments, from Sohiong (Prunus nepalensis). This study demonstrated that Sohiong have high anthocyanins content and antioxidant property, indicating an immense potential for the fruit producers and food processors.

Design/methodology/approach

Response surface methodology was used to optimize the conditions for extraction of anthocyanins from Sohiong using conventional solvent extraction.

Findings

The optimum conditions for extraction were found to be 36.75°C temperature, 60.32 per cent ethanol concentration and 2.39 per cent citric acid concentration with recovery of 45 per cent total extract yield, 858.84 mg C3G/100g DM anthocyanin content and 824.91 mg GAE/100g DM phenolic content with in-vitro antioxidant activity of 31.40 mmol AEAC/100g DM for FRAP and 84.66 per cent DPPH scavenging capacity (20mg/ml). The F-values and high values of adjusted determination coefficient for each response imply high level of significance of the fitted models.

Practical implications

Extracted color can be used in food and pharmaceutical industries.

Social implications

Pigment extracted is from a natural source and possesses high antioxidative activity and potential health benefits. With increasing demand for natural colors and other additives, there is a wide range of applications of the pigment as natural colorant in the food and pharmaceutical sector.

Originality/value

Selected plant source, i.e. Sohiong, was not used earlier by any researcher to extract anthocyanins for potential applications as food colorant.

Details

Pigment & Resin Technology, vol. 47 no. 6
Type: Research Article
ISSN: 0369-9420

Keywords

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