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The aim of the work is to investigate the consequences of the addition of the flaxseed mucilage, as a bio-admixture, on Portland cement materials. Flaxseed mucilage (FM) which is highly soluble in water is part of the flaxseed cake, a by-product of the seed-crushing industry. The addition of biobased admixtures plays a crucial role in the optimization of cementitious material properties and thus in the competitiveness of the material. The influence of flaxseed mucilage addition way (anhydrous and in-solution forms) on cement paste hydration has been studied using FTIR, TGA, and calorimetry. Portland cement mortars (W/C = 0.6) are used to evaluate the impact of the mucilage on the mechanical properties and bulk density. When FM is added solubilized, at the studied admixture rate (0.75% w/w), setting is excessively delayed (more than thirteen-times slower compared to standard conditions without admixture). When FM is added anhydrous, few impact is noticed on setting. However, TGA analysis pointed out a heterogeneous dispersion of the anhydrous FM during the mixing process. More, the anhydrous FM causes water deficit in the mixture due to its high hygroscopy, resulting in a 10% decrease in bulk density. Both flexural and compressive strengths are reduced, particularly for the mortars formulated with anhydrous FM (− 45% and − 54% respectively). Data suggest that FM delays the setting process due to a “poisoning effect,” without hindering the hydrate growth nor changing mineralogy confirmed by FTIR.

The feasibility of processing cauliflower by ohmic heating was investigated. Firstly, cauliflower florets were precooked in tap water at low temperatures (40–70 °C) for 0 to 60 min. A control sample was cooked at 95 °C for 5 min. No significant textural differences were found between samples treated at 40 or 50 °C and fresh samples, but the firmness of samples cooked above 60 °C decreased. The effect of precooking time was not found to be significant. Secondly, low temperature precooking was performed in salted water for 30 min and followed by ohmic heating (holding time 30 s at 135 °C). After ohmic heating, florets pretreated at low temperatures were firmer than control samples. The firmness of florets precooked at 40 °C or 50 °C was considerably increased (>300%) compared to those precooked at 95 °C. Low-temperature precooking increased the firmness of cauliflower subjected to ohmic heating. The experimental results show that ohmic heating combined with low-temperature precooking in saline solutions offers a viable solution to high temperature/short time sterilisation of cauliflower florets. © 1999 Society of Chemical Industry