Starch energy content

Carbohydrate accounts for about 40% of the energy content of a normal meal. In the UK, the daily intake is typically 60 g starch, 120 g sucrose, 30 g lactose, 10 g of glucose... 

Starch should provide a high proportion of the energy content of the diet since most foods containing starch contain some non-digestible starch, one form of fibre there are several reasons why fibre is important (Chapter 6). 

Proteins are useful for their energy content, just as starches, sugars, and fats are, but perhaps the greatest importance of proteins lies with how our bodies use them for building such structures as enzymes, bones, muscles, and skin. 

Tl ie energy content of food carboliydrate and food protein is J7 kj/g, whereas that of food fat is 38 kj/g. The energy content of ethanol is 3 kJ/g. Though fairly accurate, these values are only generalizations. For example, consider the energies of different carbohydrates 17,2 kJ/g of starch, 16.6 kJ/g of sucrose, 15,9 kJ/g of glucose. 

The PKU diet may also include modified low-protein foods, such as low-protein pasta, breads, and baking mixes that are made from wheat or other starch, thus reducing the phenylalanine content. These products usually are ordered from specialty food companies. The benefit of using these products is that they increase the energy content and the variety of foods in the diet, yet most are very low in phenylalanine. There are... 

Over the last years food wastes have earned an increasing attention as feedstock for hydrogen production they include kitchen refuse, municipal wastes (a part of), food industry co-products (oil mill, cheese whey) and starch manufacturing wastes. Food wastes show high energy content (85—95% of volatile solids and 75—85% moisture) and high biodegradability, which favours microbial anaerobic development. 

From com starch, e. g., non-sweet oligosaccharides (maltodextrins, DE5) which dissolve completely in hot water are obtained. When this solution is cooled, a gel is formed which has the texture of edible oil. It can partially replace fat, e. g., in margarine, allowing a 35% reduction of the energy content. 

By-products of starch production are fodder and raw materials for other syntheses. The energy content was used as the basis for allocating energy use and the environmental impacts to the main product and the by-products. For potatoes, this gives an allocation ratio of main products to by-products of 2 1 for sorbite production, the ratio of main products to by-products is 0.52. 

Figure 7.8 Specific mechanical energy of extruder for mixtures with differing starch type contents.

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