Nutrition and Applications of Wholemeal Flour Compared to Refined Flour

Nutrition and Applications of Wholemeal Flour Compared to Refined Flour

                                                                                           Edited: www.immyhitech.com  www.immy.cn 

When you stand in front of the flour aisle in the supermarket, have you ever been caught between a rock and a hard place? Wholemeal flour and refined flour, two brothers from the same grain, have taken very different paths due to different processing techniques.

They are not only different in terms of nutritional value, but also in terms of culinary characteristics. This difference is the development 

process of the food industry, mankind's natural and refined eternal exploration of the vivid embodiment.

First, the essential difference in nutritional value

Wholemeal flour retains the bran, germ and endosperm of wheat, which is a natural nutritional treasure trove. Every 100 grams of whole wheat flour contains 12.2 grams of dietary fibre, which is more than four times that of refined flour.

The bran is rich in B vitamins, and the total amount of thiamin, riboflavin and niacin is 60 per cent higher than in refined flour. 

The germ portion, on the other hand, is rich in vitamin E and essential fatty acids, nutrients that are often lost in large quantities during the processing of refined flour due to the stripping of the germ.

In contrast, refined flour loses 83 per cent of its manganese, 72 per cent of its iron and 65 per cent of its calcium during processing.

Although modern flour mills compensate for these losses through fortification, artificially added synthetic nutrients have never 

been able to match the naturally occurring forms in terms of bioavailability.

While phytic acid in wholemeal flour may interfere with mineral absorption, its naturally formulated micronutrients have a better 

synergistic effect for better nutritional performance.

Wholemeal flour has a Glycemic Index (GI) of 53, significantly lower than refined flour's 71. The beta-glucan in bran slows 

glucose absorption, which is of practical importance for blood sugar management.

Studies have shown that long-term consumption of whole grains can reduce the risk of type 2 diabetes by 21 per cent, thanks

 to their complete nutritional matrix.

Second, the process gamut of physical properties

The bran fragments in wholemeal flour form a unique physical barrier that increases the water absorption of the dough by 

15-20%. This characteristic requires the baker to adjust the liquid ratio and extend the fermentation time by 30 per cent.

Fat oxidising enzymes in the germ break down gluten proteins, resulting in a loss of gluten strength in wholemeal doughs. 

For this reason, wholemeal flour usually needs to be used in conjunction with high-gluten flour in order to obtain the desired 

volume of bread.

The fine texture of refined flours, on the other hand, is due to the precise milling process. Its particle size is controlled at 

75-150 microns, enabling the formation of a homogeneous and dense gluten network.

Industrially produced refined flours are oxidised and have a stable and controlled gluten quality with a batch consistency

 of over 98%, a level of standardisation that is difficult to achieve in home baking.

In baking applications, refined flour produces cakes with fine organisation and pore diameters of up to 0.1-0.3 mm, 

while wholemeal cakes usually have pore diameters of 0.5 mm or more.

In terms of bread specific volume (volume/weight), refined flour breads can reach 4.5-5.0 ml/g, while wholemeal breads 

usually do not exceed 3.8 ml/g. This difference mainly stems from the physical cutting effect of bran on the gluten network.

III. Intelligent choice of application scenarios

In the production of wholemeal bread, the segmented fermentation method is recommended: 70% of the flour is 

first fermented in a liquid seed, and the remaining flour is added after 12 hours.

This process activates the enzyme system in the bran and degrades part of the cellulose, thus improving the texture 

of the bread by about 30%. In addition, the addition of 1% vitamin C strengthens the gluten network and compensates

 for the detrimental effects of germ protease.

The elongation advantage of refined flour is particularly evident in Chinese pastry production. Dumpling skins have an

 elongation at break of up to 180 per cent, compared to only 120 per cent for wholemeal dumpling skins.

For wonton skins that require a thin, tough texture, it is recommended that refined flour be compounded with potato 

starch in a ratio of 9:1, which gives optimum transparency and flexibility.

In modern kitchen practice, blending wholemeal flour with refined flour in the ratio of 1:2 retains 85% of the nutrients 

of wholemeal and gives processing properties close to those of refined flour.

When making biscuits, the proportion of wholemeal flour can be up to 40%, and its rough texture can, on the contrary, 

enhance the crunchiness of the biscuits and reduce the breaking force by 15%, resulting in a more pleasurable eating experience.

Technology helps balance health and flavour

At the crossroads of food choices, wholemeal flour and refined flour are not either/or options. After understanding their

 essential differences, it is wise to make functional ratios according to specific needs.

Choose wholemeal flour for its nutritional integrity when you are looking for healthier products, and refined flour for its 

consistent performance when you are making delicate pastries. Finding a balance between the two is the essence of modern

 food civilisation.

What is to be expected is that the development of food technology is creating new possibilities. Innovations such as 

enzyme-modified wholemeal flour and ultra-micro-milling technology are narrowing the gap between these two 

‘brothers’.

In the future, we may be able to have a more perfect flour solution that meets both health needs and flavour enjoyment.