RESUMO
In present study, application of Isfarzeh seed (Plantago ovate L.) mucilage as fat replacer was studied in mayonnaise formulation. Fat was partially substituted by mucilage gels (2 and 3 % suspensions) at levels of 30, 40 and 50 % which were referred to as FM2-30 % (2 % gel and 30 % substitution level), FM2-40 %, FM2-50 %, FM3-30 %, FM3-40 %, and FM3-50 % formulations, respectively and the full fat (Ff) mayonnaise with 78 % oil was used as control. Physicochemical, texture and sensory analysis of Ff and Low fat (Lf) treatments were evaluated. Results indicated that Lf samples had considerably lower energy content compared with control, but higher water content than their Ff counterpart. In view of texture, FM3-30 % showed similar textural characteristics as those of control. Both Ff and Lf samples exhibited thixotropic and shear thinning behavior through rheological studies and all samples followed the power law model except FM3-40 % and FM3-50 %. Sensory evaluation demonstrated that all of mayonnaise samples, containing 3 % mucilage, were more acceptable. It was concluded that Isfarzeh seed mucilage can be used as a suitable fat replacer in mayonnaise formulation.
RESUMO
To examine the potential application of microbial transglutaminase (MTG) on semolina dough properties and quality of raw and cooked spaghetti, the effects of various MTG addition levels on the solubility of proteins, SDS-PAGE pattern of semolina dough proteins, and textural and structural properties of raw and cooked spaghetti were investigated using semolina from a high-protein good variety (MACS 1967) and a low-protein poor variety (PDW 274) durum wheat. To increase the concentration of lysyl residues and possibly enhance the extent of cross-linking of protein matrix by MTG, a commercial soy protein isolate (SPI) was added at a level of 3% (w/w) in combination with MTG, and its effect on semolina dough properties and spaghetti quality was investigated. The addition of MTG significantly decreased the solubility of semolina dough proteins. SDS-PAGE results showed that with increasing levels of MTG, a progressive decrease in the intensity of the bands corresponding to molecular weight of around 66 kDa was observed. Protein cross-linking reaction catalyzed by MTG resulted in changes in dough properties, dry spaghetti quality, cooking quality characteristics, and microstructure of cooked spaghetti. However, the quality improvements were more evident in spaghetti from the poor variety PDW 274 than from the good variety MACS 1967. The results also showed the ability of MTG in the formation of heterologous polymers between SPI and durum wheat proteins to improve the quality of spaghetti samples.
