سمیرا بیک زاده

Cold plasma is an eco-friendly and non-thermal technique, which has become an important technology to change the physical and chemical features of polymers. Recently, cold plasma has been considered in the decontamination and modification of packaging materials in the food industry. Therefore, the objective of this study was to survey the effect of using low-pressure oxygen plasma treatment on the surface and physicochemical properties of starch-chitosan composite films.

The low-pressure oxygen plasma treatment of starch-chitosan composite films was carried out using a plasma cleaner system at various times (4, 8 and 12 min). Afterwards, the surface properties and physicochemical properties of untreated and plasma-treated films were compared.

The surface roughness and hydrophilicity of the films were increased after tlasma treatment. The tensile strength of the plasma-treated films was improved. Plasma treatments decreased the oxygen permeability of the films but no significant change in their water vapor permeability was observed.

In this study, although plasma treatment increased the tensile strength and decreased oxygen permeability of the films, their surface hydrophilicity was increased too. There is a need for further studies to modify the starch-chitosan composite film by plasma treatment.

Flaxseed oil, as a potential source of polyunsaturated fatty acids, is susceptible to oxidation. Yeast cells of Saccharomyces cerevisiae and β-glucan can be used as biocompatible and biodegradable matrices for the protection of this nutritious oil from oxidation in foods enriched with omega-3 fatty acids. The aim of this study was to investigate quality properties of breads containing encapsulated and free flaxseed oils.

Flaxseed oil was encapsulated in either yeast cells or β-glucan. Functional wheat bread samples were prepared using unencapsulated and encapsulated flaxseed oils. These were compared with control samples in terms of dough rheological and bread quality parameters.Results and

Encapsulation significantly increased dough rheological properties (G′ and G″ values), firmness and density and decreased lightness, compared to control samples. Breads, containing flaxseed oil encapsulated in yeast cells, showed a lower peroxide index and a higher α-linolenic acid value, compared to two other samples containing oil samples. This showed a better protection of unsaturated fatty acids against deleterious oxidation reactions. Results of this study indicate that addition of microencapsulated flaxseed oil into breads helps preserve sensory properties of the control sample, compared to breads fortified with free flaxseed oil.Conflict of interest: The authors declare no conflict of interest.

Retarding the staling rate of baked products is one of the issues which has nutritional and economical importance. The application of hydrocolloids in bakery products increases shelf life and postpones staling. Nowadays, it appears to be a necessity to study, extract and determine the functional properties of the hydrocolloid components of native plants since most of them are imports. So, in this study the effect of different concentrations (0, 0.25, 0.5 and 0.75%) of a native hydrocolloids (psyllium seed mucilage) and a commercial hydrocolloid (xanthan) on quality properties of sponge cake were investigated. The results showed that the lowest specific gravity was related to sample containing 0.25% xanthan. During the storage time, the highest moisture content and the lowest firmness were observed in sample including 0.25% xanthan and 0.75% psyllium. The samples containing 0.25% and 0.5 % xanthan had no significantly difference (p>0.05) compared to the sample with 0.75% psyllium for volume and the overall acceptability. In general, it can be concluded that the properties of sponge cake containing 0.75% psyllium gum were approximately equivalent to samples including 0.25% and 0.5% xanthan.

Sponge cake is of bakery product with approximately four weeks shelf- life. Retarding the staling rate of baked goods is one of the most important issues which is of nutritional and economical importance. The application of native plant and seed hydrocolloids in bakery products increases shelf life and postpones staling. So, in this study the effect of different concentrations of qodume shirazi seed mucilage 0, 0.25, 0.5, 0.75 and 1% on physical, sensory and staling properties of sponge cake were investigated. The results showed that the addition of Qodume shirazi seed mucilage up to 0.75% improved the characteristics of the product in terms of sensory, shelf life, cake batter specific gravity, volume, apparent density and symmetry. During the storage time, the highest moisture content and the lowest firmness were observed in sample including 0.75% gum. So, qodume shirazi seed mucilage can be used as an anti-staling agent in sponge cake.

Retarding the staling rate of baked goods is one of the most important issues which is of nutritional and economical importance. Application of native plant and seed hydrocolloids and mucilages with medicinal and nutritional value is an economic solution to postpone the staling phenomenon. In this study the effect of different concentrations of basil seed mucilage (0, 0.25, 0.5, 0.75 and 1% w/w) on cake batter specific gravity and physical properties of cake (volume, apparent density, symmetry, and moisture), firmness, staling and sensory attributes were investigated. The highest specific gravity was observed in sample including 1% mucilage. The samples containing 0.25% and 0.5% basil seed mucilage had no significant (p>0.05) difference compared control sample for volume, apparent density and symmetry. However, the samples containing 0.25% and 0.5% basil seed mucilage had the highest moisture content during 1, 7 and 14 days after baking. The lowest firmness was observed in sample including 0.25% gum (1, 7 and 14 days after baking). Also the results showed that the addition of basil seed mucilage up to 0.5% significantly (p