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Article
Publication date: 18 March 2019

Heloísa Alves de Figueiredo Sousa, Josemar Gonçalves de Oliveira Filho, Mariana Buranelo Egea, Edilsa Rosa da Silva, Dirceu Macagnan, Marcio Pires and José Peixoto

Banana is an important tropical fruit with high demand in the market. The ripe fruits are less resistant to transport making logistics difficult. Moreover, as a climacteric fruit…

Abstract

Purpose

Banana is an important tropical fruit with high demand in the market. The ripe fruits are less resistant to transport making logistics difficult. Moreover, as a climacteric fruit, it has a short post-harvest shelf life. Edible coatings/films, including active substances, have been used as an alternative for preserving fruits and vegetables during post-harvest period. The purpose of this study was to evaluate the incorporating clove essential oil on the properties of cassava starch films and their effect on the post-harvest quality of different banana varieties.

Design/methodology/approach

Cassava starch films incorporating clove essential oil were developed and the films were characterized with respect to moisture, thickness, solubility, water vapor permeability (WVP), biodegradability, color and in vitro antifungal activity. Cultivars such as Prata-Anã, Grand Nine, BRS Tropical and BRS Conquista were coated with cassava starch, cassava starch film with clove essential oil (CSEO) and polyvinyl polychloride (PVC). The quality of fruits was monitored during eight storage days using mass loss, total soluble solids content (TSS) and titratable acidity (TTA).

Findings

Incorporation of clove essential oil significantly increased film thickness, reduced moisture content, solubility and WVP (p < 0.05) and did not affect the biodegradability and color of the films. The essential oil incorporated films showed antifungal activity against the fungi Colletotrichum gloeosporioides and Colletotrichum musae, but not against the yeast Saccharomyces bourladii. CSEO and PVC coating were more efficient in reducing the mass loss, SS content and TTA of the coated fruits in all varieties studied. Both CSEO and PVC coatings improve the quality attributes such as TSS and TTA and reduced mass loss, of the banana varieties such as Prata-Anã, Grand Nine, BRS Tropical and BRS Conquista during storage.

Originality/value

The active film with essential oil showed antifungal activity and essential oil can be incorporated into other food systems. This study approaches a new possibility of film coating with essential oil for a banana that showed minimum weight loss and satisfactory quality and increased shelf life. This film coating demonstrates biodegradable characteristics that could be eco-friendly and sustainable to consumers.

Details

Nutrition & Food Science, vol. 49 no. 5
Type: Research Article
ISSN: 0034-6659

Keywords

Article
Publication date: 1 March 2006

A. Kalendová, D. Veselý and P. Kalenda

To identify a method of evaluation as well as conditions under which corrosion in the form of flash rusting attacks steel treated with a coating of water‐borne binders.

1023

Abstract

Purpose

To identify a method of evaluation as well as conditions under which corrosion in the form of flash rusting attacks steel treated with a coating of water‐borne binders.

Design/methodology/approach

The paper worked with soluble alkaline silicates – sodium silicate – acting as flash rusting inhibitors, while aqueous dispersion binders were used in primer paints. Sodium silicate, potassium silicate and lithium silicate were studied from this point of view. Their inhibiting properties were described with the aid of a scanning method, determination of metal weight loss and electron raster microscopy.

Findings

Sodium silicate was identified as a very good flash rusting inhibitor for applications in styrene‐acrylate water‐borne paints.

Practical implications

Sodium silicate, potassium silicate and lithium silicate can be used in industrial coatings as high‐performance inhibitors of flash rusting.

Originality/value

A coating containing corrosion defects occurring during the creation of a film loses its anticorrosion properties and provides only low anticorrosion protection against atmospheric corrosion when the film of coating is later exposed to a corrosion environment. This paper proved that silicates could be very efficient flash rusting inhibitors under certain conditions.

Details

Anti-Corrosion Methods and Materials, vol. 53 no. 2
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 1 May 1978

Lester A. Wienert

Flash rusting and corrosion undercutting of water‐thinned paint films on iron surfaces are caused by the electrochemical decomposition of that steel surface. Flash rusting is that…

Abstract

Flash rusting and corrosion undercutting of water‐thinned paint films on iron surfaces are caused by the electrochemical decomposition of that steel surface. Flash rusting is that rust‐coloured spotting which occurs as the iron is solubilized and bleeds through that water‐thinned paint film. The steel simply corrodes because of the flow of electric currents that occur as the pure iron reverts to its more stable compounds: ferric hydroxide, hydrated ferric oxides and ferric oxides. This paper reviews the chemistry of flash rusting and corrosion undercutting and reports on the successful applications of modified barium metaborate in providing both initial and long‐term corrosion resistance for water‐thinned paints on steel. Several physical factors that contribute to flash rusting and corrosion undercutting are also discussed.

Details

Anti-Corrosion Methods and Materials, vol. 25 no. 5
Type: Research Article
ISSN: 0003-5599

Article
Publication date: 29 May 2020

Manish Kumar Chatli, Rajesh V. Wagh, Nitin Mehta, Pavan Kumar and Om Prakash Malav

The physical, biomechanical and chemical properties of the composite biodegradable films are examined by their chemical composition, structure, processing conditions and…

Abstract

Purpose

The physical, biomechanical and chemical properties of the composite biodegradable films are examined by their chemical composition, structure, processing conditions and economics. Therefore, the purpose of the study was to develop standard composite biodegradable films by optimizing the process (drying time and temperature) and composition (whey protein concentrate; WPC and sodium alginate; SA).

Design/methodology/approach

Composite WPC–SA films were developed using the Box–Behnken design of response surface methodology (RSM), with individual and interactive effects of process variables on the response variables (quality characteristics). Three independent factors at three different levels (WPC: 5–7 g, SA: 0.1–0.5 g and drying temperature: 35°C–45°C) were evaluated for their effects on physical and biomechanical properties, namely, thickness, penetrability, moisture content, water vapor transmission rate (WVTR), density, solubility, transmittance and color variables. The results were analyzed using ANOVA. For each response, second-order polynomial regression models and resulting equations were developed.

Findings

The response surface plots were constructed for representing a relationship between process parameters and responses. All responses were optimized as the best and desired, namely, thickness (180 µm), penetrability (7.63 N), moisture (28.05%), WVTR (1.87 mg/m2t), solubility (36.12%), density (1.33 g/ml), transmittance (40.55%), L* value (52.50), a* value (0.35) and b* value (13.70). The regression models exhibited “good fit” of experimental data with a high coefficient of determination. A close agreement was found between experimental and predicted values.

Practical implications

These biodegradable films can be promisingly used in the food packaging system without the problem of disposability.

Originality/value

The composite films with proteins and polysaccharides can be developed, which have improved physical and biomechanical properties.

Details

Nutrition & Food Science , vol. 51 no. 2
Type: Research Article
ISSN: 0034-6659

Keywords

Article
Publication date: 12 January 2010

Zonggen Qin and Weiping Tu

The purpose of this paper is to modify the surface property of polyacrylate latex films using only small amounts of fluorinated acrylate and to optimise the results of such a…

1107

Abstract

Purpose

The purpose of this paper is to modify the surface property of polyacrylate latex films using only small amounts of fluorinated acrylate and to optimise the results of such a modification.

Design/methodology/approach

The core‐shell particles with polyacrylate rich in core and containing fluorinated polymer rich in shell are prepared by a two‐stage semi‐continuous emulsion polymerisation under kinetically controlled conditions. The surface properties of the latex films produced from the core‐shell particles are investigated by optical goniometer measurement as well as contact angle method.

Findings

The latex films produced from the core‐shell particles exhibited surface energy of around 10 mN/m. The angle resolved X‐ray photoelectron spectrum measurements showed an increased average fluorine concentration in a surface layer thickness of a few nanometres, when compared to the fluorine concentration in the bulk.

Research limitations/implications

Methyl methacrylate, butyl acrylate and N‐methylol acrylamide monomers are used as co‐monomer to form the shell with fluoroalkyl methacrylate. By preparing core‐shell emulsion with a fluoropolymer in the shell phase, the surface property of polyacrylate latex films is efficiently modified by using only small amounts of fluorinated acrylate monomer.

Practical implications

The method developed provided a simple and practical solution to improving the surface property of polyacrylate latex films.

Originality/value

The method for enhancing surface property of polyacrylate latex films is novel and can find numerous applications in surface coating.

Details

Pigment & Resin Technology, vol. 39 no. 1
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 8 May 2018

Pierre Lavoie, Dorian Pena, Yannick Hoarau and Eric Laurendeau

This paper aims to assess the strengths and weaknesses of four thermodynamic models used in aircraft icing simulations to orient the development or the choice of an improved…

Abstract

Purpose

This paper aims to assess the strengths and weaknesses of four thermodynamic models used in aircraft icing simulations to orient the development or the choice of an improved thermodynamic model.

Design/methodology/approach

Four models are compared to assess their capabilities: Messinger, iterative Messinger, extended Messinger and shallow water icing models. They have been implemented in the aero-icing framework, NSCODE-ICE, under development at Polytechnique Montreal since 2012. Comparison is performed over typical rime and glaze ice cases. Furthermore, a manufactured geometry with multiple recirculation zones is proposed as a benchmark test to assess the efficiency in runback water modeling and geometry evolution.

Findings

The comparison shows that one of the main differences is the runback water modeling. Runback modeling based on the location of the stagnation point fails to capture the water film behavior in the presence of recirculation zones on airfoils. However, runback modeling based on air shear stress is more suitable in this situation and can also handle water accumulation while the other models cannot. Also, accounting for the conduction through the ice layer is found to have a great impact on the final ice shape as it increases the overall freezing fraction.

Originality/value

This paper helps visualize the effect of different thermodynamic models implemented in the same aero-icing framework. Also, the use of a complex manufactured geometry highlights weaknesses not normally noticeable with classic ice accretion simulations. To help with the visualization, the ice shape is presented with the water layer, which is not shown on typical icing results.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 28 no. 5
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 1 March 1962

J.T. Harrison

Methods used to prevent the corrosion of feed line surfaces and minimise accumulation of corrosion product in the feed water are mentioned in this article, including acid washing…

Abstract

Methods used to prevent the corrosion of feed line surfaces and minimise accumulation of corrosion product in the feed water are mentioned in this article, including acid washing prior to operation and the use of volatile and filming amines as inhibitors. The type of corrosion occurring on the steam side of the cupro‐nickel feed heater tubes and in the mild‐steel surge tanks of the closed‐circuit water steam cycle of C.E.G.B. boiler plant is described in some detail.

Details

Anti-Corrosion Methods and Materials, vol. 9 no. 3
Type: Research Article
ISSN: 0003-5599

Article
Publication date: 1 February 1992

S.C. Gupta and M.C. Shukla

Water soluble epoxy‐amine adducts were prepared by reacting epoxy resin with diethanolamine in different molar ratios. These adducts were further partially esterified with linseed…

Abstract

Water soluble epoxy‐amine adducts were prepared by reacting epoxy resin with diethanolamine in different molar ratios. These adducts were further partially esterified with linseed oil fatty acids. Aqueous coating compositions for cathodic electrodeposition were prepared from epoxy‐amine adducts and esterified epoxy‐amine adducts separately. Film properties of cathodically electrodeposited coatings were evaluated and studied. It was observed that coatings based on 20% and 30% esterified epoxy‐amine adducts had good overall film properties.

Details

Pigment & Resin Technology, vol. 21 no. 2
Type: Research Article
ISSN: 0369-9420

Article
Publication date: 1 February 1998

J.I. Amalvy

The effects of amount of conventional surfactant sodium dodecyl sulfate in the synthesis of carboxylated acrylic latices prepared by semicontinuous emulsion polymerization method…

Abstract

The effects of amount of conventional surfactant sodium dodecyl sulfate in the synthesis of carboxylated acrylic latices prepared by semicontinuous emulsion polymerization method were investigated. The properties considered were particle size and colloidal stability by addition of sodium chloride solution, on the latex system and water sorption, tensile strength at break and elongation, on latex films. It was found that the surfactant concentration had an important effect on the above mentioned properties. The particle size decreases with increasing surfactant concentration and the colloidal stability has a maximum value. The critical coagulation concentration value found in this work, seems to indicate an additional stabilisation of latex particles, due to a steric factor. The water uptake and the mechanical behaviour of latex films are affected considerably when SDS concentration rises. In conclusion, depending on the final use of latex, there is an optimal surfactant concentration for which the properties are appropriate.

Details

Pigment & Resin Technology, vol. 27 no. 1
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 8 February 2016

Arvind Soni, G Kandeepan, S. K. Mendiratta, Vivek Shukla and Ashish Kumar

The purpose of this paper was to develop an antimicrobial edible film coated with essential oils for packaging application with characterization of its physicochemical properties…

Abstract

Purpose

The purpose of this paper was to develop an antimicrobial edible film coated with essential oils for packaging application with characterization of its physicochemical properties. Livestock products especially meat products need special packaging system for protection. The most well-known packaging materials are polyethylene or co-polymer-based materials which have led to serious ecological problems due to their non-biodegradability and non-renewable nature. There has been a growing interest for edible films in recent years trying to reduce the amount of wastes, capable of protecting the food once the primary packaging is open, and because of public concerns about environmental protection. Various kinds of antimicrobial substances can also be incorporated into edible films to improve their functionality, as these substances could limit or prevent microbial growth on food surface.

Design/methodology/approach

Biopolymers such as carrageenan and carboxymethylcellulose and their various combinations were tried to develop an edible film. The levels of antimicrobial substances such as oregano and thyme essential oils were standardized on the basis of their minimal inhibitory concentration against Escherichia coli, Salmonella pullorum, Staphylococcus aureus and Listeria monocytogenes. Standardized edible film coated with standardized concentration of essential oil was examined for different physicochemical properties and compared with edible film without essential oil.

Findings

In total, 1.5 per cent (w/v) solution of carrageenan was found best suited biopolymer for edible film formation on the basis of thickness, transparency and elongation ability. Combined concentration of oregano (0.02 per cent) and thyme (0.03 per cent) essential oils were found to be best suited for coating the edible film as antimicrobial application.

Research limitations/implications

Future research may benefit from the present attempt in evaluating the potency of easily available agricultural by produces for preparation of economically viable edible film incorporated with various natural biopreservatives in combination for the enhancement of shelf life.

Originality/value

Antimicrobial packaging for enhancing the quality and shelf life of stored meat products offers great scope for further research in this field. Moreover, the literature pertaining to the application of edible films containing biopreservative for chicken meat products is very limited.

Details

Nutrition & Food Science, vol. 46 no. 1
Type: Research Article
ISSN: 0034-6659

Keywords

11 – 20 of over 12000