Background and Objectives: Manipulation of protein-polysaccharide interactions provides an opportunity to control the stability and texture of food emulsions. Proteins are surface-active ingredients and can function as effective emulsifying agents also polysaccharides with polyelectrolytes capacity can impart excellent colloidal stability to emulsion droplet by a combination of electrostatic and steric mechanisms. The aim of this study is production of reduced-fat mayonnaise using electrostatic and covalent of &beta-lactoglobulin and Farsi gum as stabilizer, as well as elimination of cholesterol and reducing application of other stabilizers.

 Materials and Methods: At first, electrostatic and covalent complexes of &beta-lactoglobulin and Farsi gum with dry and wet heat treatment were produced. Then Farsi gum and all of the complexes with 1% wt concentration were used in the mayonnaise. The samples were compared in terms of droplet size distributions, apparent viscosity, firmness, color and microscopic analysis. 

Results: Comparison of mean droplet size of the samples showed that mayonnaise contained dry-heated (for one week at 60 ºC and relative humidity of 75%, 1:1 biopolymer mixing ratio) &beta-lactoglobulin-Farsi gum complex (D1/11) had the smallest size. Mayonnaise containing Farsi gum and W/1:2/6.69 (wet-heated &beta-lactoglobulin-Farsi gum complex with 1:2 biopolymer mixing ratio and pH=6.69) had mean droplet size similar to commercial mayonnaise. Mayonnaise containing Farsi gum showed non-uniform microstructure by microscopy observation. Commercial mayonnaise had the highest apparent viscosity followed by mayonnaise containing Farsi gum. Firmness result also had the same trend (P<0.05). Commercial samples showed significant differences and the highest yellowness compared to others due to the presence of egg.

Conclusions: According to the above results, &beta-lactoglobulin-Farsi gum complexes can be used as emulsifier and stabilizer in mayonnaise and salad dressing.

Background and Objectives: Firstly, nanopeptides from wheat gluten hydrolysates were prepared by desolvation method and Fe₃O₄ magnetic nanoparticles were prepared by co-precipitation method. Afterwards, the surface of magnetic nanopeptides were coated with prepared nanopeptides and inulinase was immobilized on prepared magnetic nanopeptides by covalent bonding. The structural and functional characteristics of prepared nanoparticles and immobilized enzyme were determined by using <span style="font-size:10.0pt;line-height:115%;mso-ascii-font-family:" times="" new="" roman";="" mso-ascii-theme-font:major-bidi;mso-hansi-font-family:"times="" mso-hansi-theme-font:major-bidi;mso-bidi-font-family:"b="" nazanin""="">spectrophotometry in UV / VIS region and field emission scanning electron microscope methods.

Results: The morphology of magnetic nanoparticles were shown spherical also gluten peptides were spherical with short fibers. Kinetic parameters of immobilized enzyme, compared with the free enzyme, were improved and the enzyme loading on magnetic nanopeptides was calculated (7.5 mg Enzyme / g Support) 74% . Immobilize enzyme preserved 69.9% of their initial activity after 12 cycles of hydrolysis. Half-Life of immobilized enzyme at 60 ° C compared to the free enzyme was increased about 1.5 times.

Conclusion: The use of magnetic nanopeptides of wheat gluten hydrolysates for immobilization of the inulinase is an efficient method along with the increase in stability and improvement in enzyme performance for high fructose syrup production.