Eliminating the use of fat in the production of extruded snacks by applying starch coating

High content of fat and low nutritional value have led the consumption of extruded snacks to be strongly restricted in several countries. After extrusion, in conventional procedures of snacks production, the product is subjected to a fat spray to facilitate salt adherence. For this purpose, eight to ten percent (based on product mass) of vegetable fat is applied to the product. The objective of the research reported in this paper was to fully replace the use of fat in the production of snacks with a cassava starch coating focusing on reduced fat consumption. Based on experimental design the most satisfactory concentration of starch in aqueous suspension, sprayed on the snacks at 10% w/w based on final product following heating to 80°C, was identified. We used a single screw extruder Imbramaq IBX50 to produce the snacks. The extrudates were analysed for specific volume (m/v), texture (texturometer Stable Micro Systems Texture Analyser TAXT2), retraction index (vf/vs), moisture, total lipids, peroxide value and sensory properties using 64 tasters comparing the new and standard products. The analyses were carried out shortly after snack manufacture and every seven days during the whole shelf life of the product. The main results indicate that the treatments that used starch coating did not present significant differences among each other. However, these treatments had a positive impact on maintaining texture and protection against oxidation was significantly higher than for fat coated snacks. Thus, the use of cassava starch as a snack coating presents a viable alternative to oil coating. It not only enables the reduction of the lipid content in these products but it also imparts enhanced shelf life properties.