Valorisation of cold-pressed almond oil’s cake as raw material for the preparation of naturally gluten-free flour for specific food applications

Abstract

Almond cake is a by-product of mechanical press extraction of almond oil intended mainly for the cosmetics industry. According to the circular economy for zero waste, the purpose is to reuse this byproduct to prepare natural gluten-free flour to replace part or all of the whole soft wheat flour (SWF) in specific foods. The almond by-product after grinding was sifted on a sieving shaker equipped with 4 mesh sieves 1mm, 500µm, 250µm, and 100µm. The obtained fractions were compared with SWF, based on analysis’s results for ash and colour (L*, a*, b*), contents of proteins, fibres, total sugars, reducing sugars and bulk density. Significant difference was detected between the gluten free fractions of almond meal and SWF, particularly for protein content and colour. The flour obtained from the almond cake is naturally gluten-free; therefore, it cannot have the properties of a baker’s flour of soft Wheat. This naturally gluten free flour would be suitable for gluten free specific baked goods, like cookies, biscuits and crackers, particularly intended to celiac people who cannot consume bakery products made from flour of certain cereals (wheat, barley, rye, oats), or their derivatives.