Nixtamal hardness is an important characteristic to evaluate in order to obtain corn masa and tortillas with good attributes. There is a need for instrumental methods that measure nixtamal hardness in individual kernels. The purpose of this research was to construct and to evaluate a cell to measure texture in individual kernels of nixtamalized maize. The nixtamal punch cell (NPC) consisted of two sections: Section A included three needles of predetermined diameter (punch), and attached to the texturometer crosshead. Section B consisted of a rectangular aluminum plate with three reservoirs placed in a triangular arrangement, and set in the bottom of the texturometer. Individual nixtamal kernels were placed into the reservoirs where they were punched. The NPC was standardized with commercial nixtamal, and the factors evaluated were: punch diameter (1.75, 2.00 and 2.25 mm), and texturometer crosshead speed (25, 50 and 75 mm/min). The two hardness characteristics obtained with the NPC were maximum force (MF) to rupture the nixtamal and the modulus of elasticity (ME). The best diameter and crosshead speed to run the NPC were 2 mm and 75 mm/min. Coefficients of variation were 29.0% for the MF and 31.0% for the ME. Variability is attributed to intrinsic heterogeneity of the nixtamal kernels, and not to the cell. The NPC was able to detect differences in hardness between nixtamal made in two different factories.
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