• Daiga Konrade Latvia University of Agriculture,Faculty of Food Technology
  • Dace Klava Latvia University of Agriculture, Faculty of Food Technology
  • Ilze Gramatina Latvia University of Agriculture, Faculty of Food Technology
Keywords: apple by- products, crispbreads, extrusion, dietary fibre


In the production of apple juice, the by-products such as the peel, bark and seeds remain biologically active substances and a good source of dietary fibre. The aim of our study is to incorporate apple by-product flour (ABF) into cereal crispbreads and to determine the total dietary fibre (TDF) content, the colour and the structural changes after addition of ABF to cereal based extrudates. Hot air drying was applied for the preparation of ABF from apple pomace. For the development of new products, a laboratory single-screw extruder GÖTTFERT 1 L series (Germany) was used. An extrusion screw (compression ratio 2:1) at a speed of 60-80 rpm and a rectangular die (aperture: 20 mm wide, 1.0 mm high, 100 mm long) were also used. The basic ingredients for extruded crispbreads were wheat flour, rice flour, wheat bran, rye flour, oat flour with addition of ABF in different proportions (5%, 10%, 15%).The content of total dietary fibre (TDF) was determined according to the AOAC –AACC method No.985.29 by FOSS Analytical Fibertec E 1023 system. Density, textural properties and colour was also determined. The obtained results showed an increase of TDF from 9.39 to 15.89 g 100g-1 in wheat crispbreads with AB and from 15.8 to19.89 g 100g-1 in rye crispbreads with ABF, hardness of products with ABF was from 17.2-21.7 N and density from 0.24-0.35g cm-3, moisture of final product was 3.89-4.24±0. 01%. The main purpose of the current research was to determine the effect of ABF addition to cereal crispbread content, of the TDF and the textural properties.


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