Observations on the formation and textural properties of “tapiocas”, a traditional cassava-based food from the Northeast of Brazil

Abstract “Tapioca” from northeastern Brazil, a starchy, sintered pancake-like product prepared from cassava that is a staple food for much of the regional population. The objective of this work was to propose a specification of tapiocas based on the effects of the water content of cassava starch and the preparation time and temperature of the tapiocas on their physical and structural characteristics. Tapiocas were prepared by sintering defined amounts of cassava gum with a variation in water content between 15% w/w and 45% w/w on a cooking surface that was set at a temperature between 100 °C and 300 °C, for preparation times of 120 s and 210 s. Post-preparation, the tapioca samples were qualitatively evaluated for structure and cohesivity. Based on these observations, temperature-water content diagrams that delimited the regions of tapioca formation were elaborated. Our results demonstrate that tapiocas are thin (2–6 mm) starchy slabs characterized by a continuous gelatinous and translucent core that is formed by starch that is fully or near fully gelatinized. Both the top and bottom crust of the tapiocas are formed by starch particles that have retained their granularity and are thus not or only partially gelatinized. The minimum starch water content for tapioca formation turns out to be 37% w/w for sample thicknesses between 2.5 and 5 mm and at cooking temperatures of 250 °C or higher. The minimum tapioca formation temperature decreases somewhat with increasing water content. However, for the 5 mm thick samples, tapiocas could not be formed at temperatures below 200 °C even at higher water contents. Tapioca texture parameters including hardness (5.4–49 N), springiness index (0.54–0.92), cohesiveness (0.47–0.81), resilience (0.15–0.56) and cutting force (4.1–27 N) were mainly influenced by cooking time and to a lesser degree by the cooking temperature, provided that the temperature was above a minimum threshold. Our results are of importance both for small producers and chefs as well as larger industrial producers, as they allow to rationally develop and optimize tapioca recipes.