Lipid wheat flour

BCR RM 40 Wholemeal Wheat Flour a <0.03 w.c. = 1.70 + 0.04 %. It is important to note that this material is likely to have handling problems due to its hygroscopic behavior. The water activity is in the range where the monomolecular surface layer of water may be removed. Thus, deterioration of the lipids is hkely to occur during storage. 

FD Conforti, CH Harris, JT Rinehart. High performance liquid chromatographic analysis of wheat flour lipids using an evaporative light scattering detector. J Chromatogr 645 83-88, 1993. 

All wheat starches give the same A-type crystal pattern, but their degree of crystallinity is inversely proportional to amylose content. In addition, the intensity of one reflection of an amylose-lipid complex at 2 20-23° (d 4.4A) increases proportionally to the amylose level.265,271,281,284,289 The lipid content of waxy wheat starch is much lower (0.02-0.17%) than that in non-waxy wheat starch (0.6-0.7%).286,291 However, the crude fat content of waxy wheat flour is elevated by 20-40% (3-glucan and pentosan are increased by 30%.291,292 The degree of crystallinity of waxy wheat starch is reported to be 18-21% versus 13-16% for the wild type.284,289 Increases of 35% for waxy wheat starch, 23-28% for double nulls, 20-23% for single nulls and 22% for the wild type have also been reported.271... 

In the food industry, lipases are used in lipid modification processes. In these processes the texture, digestibility, or physical properties of natural lipids are modified by lipase-catalyzed transesterification reactions with lipids other than the original fatty acids. In the baking industry, lipases are used to influence the quality of bread through modification of the wheat flour lipids. Finally lipases are used for flavor enhancement of cheese in the dairy industry. 

Kissel and Yamazaki (209) studied the effects of lipid extracts from wheat flour and soy and safflower lecithins on improving cookie spread when the cookies were made from protein-fortified wheat flour. Soy lecithin was most effective, and it also improved the quality of cookies made from weak flours such as sorghum and millet (210). 

Hwang, H.I. et al., Aroma generation in extruded and heated wheat flour, in Lipids in Food Flavors, Ho, C.T. and Hartman, T.G., Eds., American Chemical Society, Washington, D.C., 1994, p. 144. 

Compound 60 has a structural similarity to the glycosphingolipids of type 61 isolated from wheat-flour lipids by Carter and coworkers.133 184... 

Blochet, J. E., A. J. P. Kaboulou, and D. Marion. 1991. Amphiphilic protein from wheat flour specific extraction, structure and lipid binding properties. In Gluten proteins 1990, ed. W. Bushuk and R. Tkachuk, 314-325. St. Paul, MN American Association of Cereal Chemists. 

Some results for the effects of addition of different lipid compounds on loaf volume of a base flour are shown in Figure 7.10 (Sroan 2007). The natural lipid from flour has been separated into two fractions polar and nonpolar. Thin layer chromatography (TLC) of the fractions is shown in Figure 7.11. Polar lipids comprise mainly galactolipids and phospholipids. Their addition enhances loaf volume. In contrast, the nonpolar fraction, which comprises mono-, di-, and triglycerides and free fatty acids as the main components, causes depression of the loaf volume. The unsaturated linoleic acid, which is the major fatty acid in wheat, also depresses loaf volume, whereas the saturated palmitic acid has no effect. Another saturated fatty acid, myristic acid, affected loaf volume negatively. 

De Stefanis, V. A., and J. G. Ponte. 1976. Studies on the bread-making properties of wheat-flour nonpolar lipids. Cereal Chemistry 53 636-642. 

A direct approach to determining composition-functionality relationships begins by separating the different chemical components. Once the components have been isolated—say, from a cereal flour—it is possible to proceed in two main ways. The first is to add the component in different amounts to the flour and measure the response in terms of some parameter of functionality. This approach has been used for elucidating the effects of lipids and proteins of wheat flour. 

An example is illustrated in Figure 11.3 (cf. Figure 7.10 in Chapter 7) for the effect of varying the natural lipid level of a wheat flour on bread loaf volume in an optimized lean formula baking test. The behavior is unusual. The nonstarch flour lipid has been solvent-extracted using chloroform and added back incrementally to the defatted flour. Small additions of lipid decrease loaf volume imtil a minimum is reached at a lipid... 

There has been increasing interest in cereal lipids because of their importance in food technology (e.g. in wheat flour) or as potential sources of significant amounts of dietary polyunsaturated fatty acids (Price and Parsons, 1974). Morrison and co-workers have conducted a systematic study of the distribution of... 

N-Acyl PE (APE) has been reported in wheat flour lipids (Bomstein, 1%5), soybean lipids (Anejae/ al., 1969), pea, and some other seeds (Dawson et al., 1969). It disappears rapidly on seed germination (Dawson et al., 1969). Dawson et al. (1969) reported as much as 13.3% of lipid phosphorus as APE in the mature seed of oat (A. sativa L.). Wilson and Rinne (1974) measured the phospholipids of developing soybean (Glycine max L.) up to 60 days after flowering (DAF) APE was always in excess of 50% of lipid phosphorus, but in the mature seed (75 DAF) there was an amazing drop to 4.8% of lipid phosphorus. 

The fatty acid analyses of Dawson et al. (1969) and Aneja et al. (1969) showed the N-acyl group to be much more saturated than the O-acyl group. Wilson and Rinne (1978) have reported that APE has approximately 70% 18 2 at all stages of development of the seed, but they did not measure O-acyl and A -acyl separately. MacMurray and Morrison (1970) have reported that wheat flour lipids also are rich in the Al-acyl derivatives of ethanolamine containing phospholipids. 

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