Fibre analysis

There is a growing interest in the inclusion of soluble fibre into the diet to help improve health. This is extending to drinks as well, with such fibre being added to milk- and fruit-based products such as smoothies . One source of soluble fibre which has attracted attention over the last few years is inulin or oligofiuc-tans. Inulin consists of oligosaccharides that are extracted from chicory or Jerusalem artichokes and that are claimed to improve colon function and to have prebiotic properties, enhancing the working of the gut. Inulin is a complex carbohydrate which can be assayed in a number of different ways. However, there are two published methods in the AO AC manual for its analysis (997.08 and 999.03). 

There are a number of well-documented, validated methods for the analysis of total fibre in food products in the AOAC manual (993.19, 993.23, 991.42, 991.43 and 958.29). Most of these are gravimetric methods where the fibre is precipitated with ethanol and washed and the fibre content calculated after allowances are made for any protein and/or ash that the precipitate contains. These methods rely on precipitation of the fibre with alcohol for their quantification, but as inulin is soluble in mixtures of ethanol and water it cannot be detected in these tests. The most recent method (2001.03) includes an HPLC stage to allow for detection of the presence of maltodextrins, which are poorly digested in the body, but this will not detect inulin. 

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Drews et al. [403] have focused on the use of SFE for quantitative analysis of fibre finishes as a replacement of current fibre analysis methods (Soxhlet) requiring chlorinated solvents to remove the finish from the fibre. It was observed that while the extraction... 

Southgate, D.A.T. (1995) Dietary Fibre Analysis. Royal Society of Chemistry, Cambridge, UK. 

The authors appreciate the help of Dr. R. Mongeau, Nutrition Research Division, Health Protection Branch, in the fibre analysis of the cereals. They also thank Mr. S. Malcolm, Food Statistics and Operational Planning, for statistical analysis of the data. 

Bresee, R R, Single fibre analysis , va. Analytical Methods for aTextile Laboratory,. 1W Weaver (ed), AATCC, Research Triangle Park, NC, 1984, Chapter 2, pp 9-28. 

Most of the techniques employed in fibre analysis are nondestructive tests to determine whether the fibre is natural (obtained from animal, plant, or mineral) or synthetic (wholly manufactured from chemicals or regenerated from natural fibres) and the fibre type (e.g., determining if the fibre is wool, cotton, nylon, polyester, etc.). Whether any chemical treatments have been carried out (such as bleaching or the use of delustrants) is noted and the colour is also determined. Many of the techniques commonly used in these analyses include low- and high-power microscopes, Fourier transform infrared (FTIR) microscopy, polarising Ught microscopy, fluorescence microscopy, and microspectrophotometry (MSP). 

A detailed study of the application of IR microscopy for single fibre analysis was undertaken. A library of 43... 

A 46-year-old woman who had worked for 5 years in a windowless decorator s studio polluted with crocidoUte sprayed to steel ceilings died from a pleural mesothelioma (Schneider et al. 2001). A fibre analysis by light microscopy showed 3162 ferruginous bodies per gram of wet lung tissue. 

The Van Soest methods of fibre analysis are used in the system of food analysis for ruminants developed at Cornell University (see Box 1.1). 

Asp N-G and Johansson C-G1984 Dietary fibre analysis. Nutrition Abstracts and Reviews 54 735-51. 

The application of SEM to polymeric materials has been reviewed [143]. Forensic fibre analysis was reviewed [164]. 

Virtually no data on dietary fibre intakes in other populations of the world have been published. They have been quoted only in the report of a study co-ordinated by the International Agency for Research on Cancer, in which dietary intake and bowel cancer incidence were compared in a Danish and Finnish population. In this study a random sample of 30 men aged 55-64 were selected from population registers in Copenhagen (Denmark) and Kuopio (Finland) and asked to record their food intakes for four days. On the fourth day they also collected a duplicate sample of all the food eaten and this was sent to Cambridge for dietary fibre analysis. 

Karlsson, H. (2006). Fibre Guide—Fibre Analysis and Process Applications in the Pulp and Paper Industry, AB Lorentzen Wettre, pp. 17-27. 

McCleary BV (2003) Dietary fibre analysis. Proceedings of the Nutrition Society 62 3-9. 

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