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Article
Publication date: 18 October 2019

Congcong Liu, Chong Wang, Keping Ye, Yun Bai, Xiaobo Yu, Chunbao Li and Guanghong Zhou

The purpose of this paper is to elucidate the influences of the animal fat and fatty acid type on the formation of polycyclic aromatic hydrocarbons (PAHs) and to propose a…

Abstract

Purpose

The purpose of this paper is to elucidate the influences of the animal fat and fatty acid type on the formation of polycyclic aromatic hydrocarbons (PAHs) and to propose a formation mechanism of PAHs in fat during electric roasting, which is a method of non-direct-contact-flame heating.

Design/methodology/approach

The effects of animal fats and model fat on the formation of PAHs were valued on the basis of the ultra high-performance liquid chromatography data. The corresponding products of the FAME pyrolysis were detected by TG-FTIR. The proposal formation mechanism of PAHs was based on the summary of the literature.

Findings

Contrary to the International Agency for Research on Cancer, DF had higher risk with 280.53 ng/g of concentration after being roasted than the others animal fats of red meat in terms of PAHs formation. This research also ensured the importance of fat on PAHs formation, the concentration of PAHs in pure fats was higher after being electric roasted than that in meat patties and juice which made from corresponding animal fat. What is more, during pure animal fats and meat products being processed, less PAHs formed in the fat with lower extent of unsaturation and lower content of linolenate. In the same way, methyl linolenate demonstrated the significant increasement to PAHs formation compared to the other fatty acids. And, the number of carbon atom and the extent of unsaturation in fatty acid affects the formation of PAHs during roasting. The detection of alkene and alkane allows to propose a formation mechanism of PAHs during model fat being heated. Further study is required to elucidate the confirm moleculars during the formation of PAHs.

Originality/value

This work studied the effect of the carbon atom number and the unsaturation extent of fats and model fats on the formation of PAHs. This work also assure the important of alkene and alkane on the pyrolysis of model fats. This study also researched the formation and distribution of PAHs in pure fats and meat products after being heated.

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Article
Publication date: 1 June 1985

David Lewis

SOURCES. Oils are essential constituents of animal and vegetable tissues and as such are found in a wide range of foodstuffs. The main sources of large quantities of oil…

Abstract

SOURCES. Oils are essential constituents of animal and vegetable tissues and as such are found in a wide range of foodstuffs. The main sources of large quantities of oil and fat are in the energy‐storing tissues. Normally, these stores are present as oils but may solidify on cooling. Hence animal fats which exist naturally at body temperatures tend to be solid at room temperatures, whilst vegetable and marine oils are often liquid at room temperature. Chemically, these differences are related to the chain length and degree of unsaturation of the fatty acid residues; shorter chain lengths and higher levels of unsaturation lead to lower melting points. Microscopically, solidification is seen as an increase in the amount of crystallinity in the fat and this can be detected by polarised light microscopy and by electron microscopy techniques. Differences in crystallinity can be found in fats from different animals — for example, beef fats are generally more crystalline than pork fats — and from different anatomical locations within a single animal — for example, exterior fats such as pork jowl fat are generally less crystalline than interior fats such as mesenteric fat.

Details

Nutrition & Food Science, vol. 85 no. 6
Type: Research Article
ISSN: 0034-6659

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Article
Publication date: 1 December 1975

Gerald Scott

The total utilisable resources of carbon in the biosphere are enormous by any standards. In the atmosphere alone there are about 700 billion tons of carbon as carbon…

Abstract

The total utilisable resources of carbon in the biosphere are enormous by any standards. In the atmosphere alone there are about 700 billion tons of carbon as carbon dioxide and in the oceans there are stored 35,000 billion tons of available carbon dioxide. These two reserves alone amount to about four times the estimated total reserves of carbon in the form of coal and oil. The essential difference between these alternative sources of carbon is that whereas the carbon in the biological cycle is being continuously circulated in a system in which the total amount of carbon remains sensibly constant (there is a further 30,000 billion tons of carbon in the form of biological organic matter), the carbon in the form of coal and oil reserves are being rapidly depleted with consequent escalating cost and the lifetime of this source of chemicals and energy is variously estimated as being between 20 and 50 years.

Details

Pigment & Resin Technology, vol. 4 no. 12
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 1 February 2001

P.C. Sarkar and K.K. Kumar

Studies different forms of lac resin, viz. sticklac, seedlac and shellac by FT‐IR spectroscopy. Also compares the FT‐IR and DRIFT spectra of lac obtained from different…

Abstract

Studies different forms of lac resin, viz. sticklac, seedlac and shellac by FT‐IR spectroscopy. Also compares the FT‐IR and DRIFT spectra of lac obtained from different host trees in an attempt to explain the differences in their physico‐chemical properties. Concludes that all lacs are a structurally similar class of compounds but differ in physico‐chemical behaviour due to minor compositional differences, especially with reference to hydroxylic content, long chain fatty acid content and unsaturation.

Details

Pigment & Resin Technology, vol. 30 no. 1
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 13 November 2007

D. Bhatia, M. Alam and P.C. Sarkar

To study the changes occurring in lac‐polyvinyl butyral (PVB) resin blends at molecular levels on baking the blends at 200°C for different intervals of time. It was also…

Abstract

Purpose

To study the changes occurring in lac‐polyvinyl butyral (PVB) resin blends at molecular levels on baking the blends at 200°C for different intervals of time. It was also to ascertain the changes in key physico‐chemical parameters of these blends, before and after applying thermal stress on these blends.

Design/methodology/approach

Films of lac‐PVB blends, applied on tin panels were baked at 200°C for different time intervals. The FTIR spectra of the blends were recorded using specular reflectance spectroscopic techniques. The results obtained were compared and reported. The blends were also tested for different physico‐chemical parameters such as scratch hardness, flexibility, adhesion, acid resistance, etc.

Findings

On baking the blends of lac‐PVB resin at 200°C for different time intervals; fragmentation reaction, that is breakdown of products into small molecules, takes place in lac‐PVB blends. Side products such as acetic acid emerge on baking the blends. Probably hydrolysis of oxirane ring also takes place leading to the release of free alcoholic groups. The lac‐PVB blends do not show any improvement in scratch hardness and are also not resistant to the action of acids. The blends made by lac‐PVB resin baked at 200°C do not seem to be compatible as no improvement in any of the physico‐chemical parameters was seen.

Research limitations/implications

Mixtures of solvents were tried for dissolving the PVB resin. In most of the solvent mixtures, PVB resin forms big lumps and is not soluble so there is a need for universal solvent for dissolving the PVB resin. The spectral studies on lac‐PVB blends were conducted qualitatively, although desirable, quantitative studies could not be carried out, due to the inherent difficulties in handling the resins.

Practical implications

The parent resins in lac‐PVB blends (baked at 200°C) do not seem to be compatible with one another as there was no improvement in any of the physico‐chemical parameters of the lac‐PVB blends. For making lac‐PVB blends, low range of baking temperature may be tried.

Originality/value

In literature, there is not much evidence of making lac‐PVB blends. This paper is the first one in attempting to obtain and correlate FTIR spectra of the lac‐PVB blends with physico‐chemical changes of the blends. This paper also highlights the convenience of the method and the scope of sophisticated data analysis such as derivative spectrometry.

Details

Pigment & Resin Technology, vol. 36 no. 6
Type: Research Article
ISSN: 0369-9420

Keywords

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Article
Publication date: 1 March 1994

P. Muturi‐Mwangi, S. Dirlikov and P.M. Gitu

Yellowing of vegetable oils in coatings continue to be a problem to paint formulators and users and to resin manufacturers. This characteristic occurs in coatings where…

Abstract

Yellowing of vegetable oils in coatings continue to be a problem to paint formulators and users and to resin manufacturers. This characteristic occurs in coatings where there is unsaturation in the triglyceride fatty acid residues of the oils used in the resin or binder. Yellowing is the single most important factor which limits the use of linseed oil‐based white paints and enamels for external use in buildings. A thorough understanding of this phenomenon is necessary to the resin manufacturer and paint formulator. Unfortunately, yellowing of vegetable oils in coatings is still a controversial subject. The chemistry behind the process is not yet known. Many factors have been attributed to causing or related to the onset and degree of yellowing. These include:

Details

Pigment & Resin Technology, vol. 23 no. 3
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 7 September 2012

Desmond Teck Chye Ang and Seng Neon Gan

The purpose of this paper is to develop palm oil‐based alkyds as ultraviolet (UV) curable coatings and investigate the parameters that affect the coating performances.

Abstract

Purpose

The purpose of this paper is to develop palm oil‐based alkyds as ultraviolet (UV) curable coatings and investigate the parameters that affect the coating performances.

Design/methodology/approach

Alkyds were formulated from palm stearin, glycerol, phthalic anhydride and maleic acid. Keeping the total molar amount of dicarboxylic acids constant, the proportions of maleic acid and phthalic anhydride were varied in order to produce polymer chains with different content of unsaturation, which is crucial for UV curability. Characterisations were carried out by FTIR and 1HNMR. The alkyds were then mixed with methyl methacrylate (MMA) monomer as active diluents and cured by exposure to UV light. Performances of the cured coatings were tested in terms of film hardness, adhesion, water and alkali resistance, and thermal stability.

Findings

Upon introducing sufficient C=C, the alkyd in combination with MMA is able to UV‐cure within short time and produce film of satisfactory quality. There are several other factors, which influence the coating properties; these include thickness of coating, ratio of alkyd to active diluents, and duration of UV exposure.

Social implications

The product is a form of green technology that could benefit the environment as it involves very low or near zero emission of volatile organic compounds (VOC).

Originality/value

The novelty of this work lies in the formulation of new products from palm stearin, leading to new developments in the surface coating and palm oil industries.

Details

Pigment & Resin Technology, vol. 41 no. 5
Type: Research Article
ISSN: 0369-9420

Keywords

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Article
Publication date: 10 April 2017

Ganesh Babu Katam, Veeresh Babu A., Madhu Murthy K. and Ganesh S. Warkhade

This study aims to find a new alternate source for biodiesel conversion. The alternate source must be easily available, and it should give more oil yield than available…

Abstract

Purpose

This study aims to find a new alternate source for biodiesel conversion. The alternate source must be easily available, and it should give more oil yield than available edible, inedible sources. To meet the fuel demand in the transportation sector with edible oil-based biodiesel causes food versus fuel crisis. In addition to this, it increases NOx and CO2 in the environment.

Design/methodology/approach

The present paper reviews the comparison of algae oil yield, fatty acid composition and its biodiesel properties’ effect on diesel engine characteristics.

Findings

Algae were the only source to fulfil fuel demand because its oil and biodiesel yield is higher than other sources. Algae can grow by capturing carbon dioxide from the environment, and its fatty acid composition is more suitable to run diesel engines.

Originality/value

There is an improvement in engine performance–emission tradeoff with algal biodiesel.

Details

World Journal of Engineering, vol. 14 no. 2
Type: Research Article
ISSN: 1708-5284

Keywords

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Article
Publication date: 29 April 2021

Nombulelo Zulu, Eugenie Kayitesi and Opeolu M. Ogundele

The effect of the addition of red palm olein (RPO) as a natural antioxidant to sunflower (SF) on chemical properties and deep-frying oxidative stability of resultant oil…

Abstract

Purpose

The effect of the addition of red palm olein (RPO) as a natural antioxidant to sunflower (SF) on chemical properties and deep-frying oxidative stability of resultant oil during storage.

Design/methodology/approach

RPO was added to SF at different levels 0, 5, 10, 15, 20, 25, 50, 75 and 100 (w/w), and potato chips were fried in oil blends repeatedly at 180 °C for 2.5 min for five days to evaluate the effect on chemical properties and oxidative stability.

Findings

The results revealed that linoleic acid and total polar compound (TPC) contents decreased in all RPO and SF resultant oil after five days of storage. Colour significantly (p = 0.05) decreased, while peroxide and iodine values were significantly lowered during storage. The oxidative stability increased significantly in the resultant oil. However, an increase in free fatty acid (FFA) before frying significantly reduced with repeated frying of resultant oil during storage. RPO (5–75%) therefore retards oxidative rancidity in the resultant oil after repeated deep frying and storage.

Originality/value

SF oil is high in polyunsaturated fatty acids but prone to oxidation upon heating and storage. RPO is an important ingredient used in industrial frying rich in phytonutrients and a better replacement to synthetic antioxidants. This study indicated that supplementing SF oil with RPO may be recommended to improve the oxidative stability of oils during frying.

Details

British Food Journal, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0007-070X

Keywords

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Article
Publication date: 9 January 2019

Nikita Mhadeshwar, Kunal Wazarkar and Anagha S. Sabnis

This paper aims to prepare acrylic functional ricinoleic acid monomer and incorporate it in conventional miniemulsion polymerization. Subsequently, paints were formulated…

Abstract

Purpose

This paper aims to prepare acrylic functional ricinoleic acid monomer and incorporate it in conventional miniemulsion polymerization. Subsequently, paints were formulated to study the variation in final coating properties.

Design/methodology/approach

Synthesis process involved the esterification of ricinoleic acid with 2-hydroxy methyl methacrylate in the presence of FASCAT-4100 catalyst. The final product of the reaction, methacrylated ricinoleic acid (MRA), was confirmed using Fourier-transform infrared spectroscopy and 1H-nuclear magnetic resonance spectroscopy and determining acid and iodine value. Further, MRA was incorporated in various concentrations (1, 2 and 3 Wt.%) along with methyl acrylate and butyl acrylate in conventional miniemulsion polymerization and paints were formulated thereof.

Findings

It was observed that with the addition of MRA monomer, flexibility of emulsion films increased as indicated by glass transition temperature and elongation value (percentage). Moreover, with the addition of MRA monomer, improvement in mechanical and chemical properties of the coatings was observed.

Research limitations/implications

Even a low concentration MRA monomer (as low as 3 per cent) caused a significant reduction in the glass transition temperature of emulsion films. Thus, it can be efficiently used in applications such as adhesives and elastomeric coatings.

Originality/value

The acrylic functional monomer derived from ricinoleic acid is unique and not yet incorporated in miniemulsion polymerization. The synthesized monomer can be used in coatings where low Tg emulsions are required.

1 – 10 of 154