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An ecological nixtamalisation process (EP) for making whole corn flour for tortillas was compared with the traditional nixtamalisation process (TP). One of the problems of TP is high level of solid losses. The aim was to evaluate the composition of these losses. In EP, dry matter losses of nejayote were from 1.2% to 1.4%, while in TP 3.2%. Nejayote from TP showed a pH of 11.9, whereas EP showed a pH close to neutral. The pericarp was retained in EP with the use of calcium salts, whereas in TP lime destroyed it almost completely. Losses of total dietary fibre in nejayote solids were about 41.2% for TP compared to an average of 17.4% for EP. Most of nejayote losses in TP were soluble fibre (30.4%), compared with EP that ranged from 6.2% to 7.9%. All compounds retained by nixtamal from EP are important sources of nutrients and dietary fibre.

The aim of this work was to characterize the mucilage extracted from six species of Opuntia. The species studied were as follows: O. atropes, O. tomentosa, O. hyptiacantha, O. streptacantha y O. joconostle and O. ficus‐indica. The first step was to find the best extraction conditions to obtain an unaltered chemical structure of mucilage. The mucilages were characterized using high‐performance liquid chromatography and Fourier transform infrared spectroscopy techniques. The optimal conditions employed to obtain the mucilage were: ratio of cladodes : ethanol solution at 50% of 1:1 (w/v), temperature of 22C and precipitation of mucilage with a solution of ethanol 96%, at a ratio of 1:4 (v/v). Mucilage from all species studied had a high content of soluble dietary fiber, ranging from 51.79 to 67.51%. In decreasing order, sugars found in the mucilages were: L‐arabinose (26.83–35.36%), D‐galactose (21.59–45.48%), D‐xylose (12.23–17.05%), uronic acids (5.59–13.91%), D‐glucose (5.18–16.21%) and L‐rhamnose (1.41–5.40%). Practical Applications This research presents an optimization method for the extraction of mucilage five wild species of cactus based on temperature and time of extraction and solvent ratio: sample used. Mucilages were characterized chemically and by chromatographic and Fourier transform infrared spectroscopy techniques and were compared with the species mucilage Opuntia ficus‐indica, the species most commercially studied. The mucilage obtained can be used for commercial purposes as additives in the food industry.

Three samples were selected representing bread, soft, and durum wheat. Uniaxial compression and stress relaxation tests were performed on wheat kernels. Force‐deformation curves from intact wheat grain typically exhibited at least two points of inflection (PI) at ≈0.1 and 0.2 mm displacement. The first PI is related to the mechanical properties of all the bran layers. The second PI (0.2 mm) seems to be the endosperm boundary near the aleurone layer. These structures had higher degree of elasticity (DE) compared to the inner endosperm (0.5–0.6 mm). Besides wheat class and specific structures of the caryopsis, moisture content is a prominent factor affecting the mechanical strength of kernels. Stress relaxation tests show that bread wheat kernels with 69.2% DE at 13% moisture decreased to 31.6% DE with additional 6% moisture content. Soft wheat kernels DE of 61.0% at 13% moisture decreased to 22.7% at 19.7% moisture. Stress relaxation revealed pronounced time‐dependence. However, the differences of stress values at 120–180 sec were not significant in all wheat classes and moisture contents evaluated. The stress values after 120 sec might be attributed to the elastic deformation of the kernels.