فصلنامه پژوهش و نوآوری در علوم و صنایع غذایی
سال ششم شماره 4 (زمستان 1396)

The aim of the study was comparing antioxidant properties and types of interaction (synergism and antagonism) between green tea and cinnamon extracts. After preparing different extracts, their antioxidant properties were measured by three methods, DPPH, FRAP, and then the ability to prevent the oxidation of soybean oil was tested. BHT was used as positive control for comparison. In this study, phenolic content of the extracts was also determined. Green tea, Cinnamon extracts and BHT were preapared in 25, 50, 100, 150, 200 and 250 µg/ml. The extracts (Green tea: Cinnamon) combined in different ratios (1:1,2:1, 1:2, 1:3, 3:1, 2:2, 1:4 and 4:1). The results of free radical scavenging DPPH, FRAP showed that green tea extract significantly (P

In this study, bionanocomposite films enriched with Oregano essential oil (OEO) and OEO nanoliposomes (2% v/v) as a preservative agent on the rainbow trout fillets were used. Trout fillets were separated into four groups: unwrapped trout fillet (control), wrapped with nanocomposite based fish myofibrillar protein (FMP)-nanofibrillated cellulose (NFC) and wrapped with nanocomposites incorporated with 2% (v/v) OEO and OEO nanoliposomes. Trout fillets were analyzed for microbiological (total viable count, psychrotrophic count, Pseudomonas spp. counts and Enterobacteriaceae counts), sensory and color characteristics. The results of microbiological analysis showed that the highest rate of growth was observed respectively in trout fillets stored in air (control), wrapped with FMP-NFC nanocomposite and the lowest counts were in wrapped samples with nanocomposite enriched with OEO and OEO nanoliposomes (P

Mayonnaise is an oil-in-water emulsion in which, egg yolk as emulsifier and different stabilizers as well as thickeners are used to improve its stability. Egg yolk is a source of cholesterol in mayonnaise which can lead to some serious health problems. In this study, in order to substitute egg, Balangu (Lallementia Royeana) Mucilage and soy protein isolate were used in different proportions to prepare mayonnaise according to the plans drawn up by the optimal mix designed. In this plan, the amount of variable was considered as 0-0.9 gr/100gr mayonnaise for egg yolk and isolated soy protein, and 0-0.75 gr/100gr Mayonnaise for Mucilage Balangu. In the next step the prepared samples were evaluated in terms of textural properties, viscosity, stability, acidity, pH and color. Finally, the results were compared with control sample (including 9% w/w egg and 0.2% Xanthan gum). According to the results obtained, the use of seed Mucilage Balangu and isolated soy protein as alternative eggs is quite possible.

In recent years, application of microwave dryer is expanding to speed up drying the agricultural products. Therefore, in this research a continuous band microwave dryer was fabricated and evaluated for drying paddy grains. In this experiments, drying process of two paddy varieties (Tarom Hashemi and Nemat) were studied in three levels of microwave power 90, 270 and 450 Watts, three different thicknesses of grain layer 6, 12 and 18 mm and five feeding speed 0.24, 0.3, 0.4, 0.6 and 1.2 mmin-1. The average slope of moisture ratio at the beginning of drying was -1.6×10-3, -1.47×10-3 and -3.16×10-3 for Tarom Hashemi and -2×10-3, -2.1×10-3 and -2.4×10-3 for Nemat at 6, 12 and 18 mm layer thickness, respectively. The finding reflected faster decreasing in the moisture content in the18 mm layer thickness compared to the two other examined layers. By evaluating all of the effective parameters of the fabricated microwave dryer on the moisture reduction and seed breakage percent, the power of 90 W, conveyor speed of 0.24 m/min-1, and layer thickness of 18 mm can be suggested for drying Tarom Hashemi paddy variety. The seed breakage percent in the proposed conditions for Tarom Hashemi was less than 10% for all of the conducted measurements.

Celiac disease is a digestive autoimmune disorder caused by the digestion of gluten. As of current, the only known treatment for this disease is to get a gluten-free diet. In this study, sorghum flour (extruded and non-extruded), xanthan and Lepidium perfoliatum seed gum were applied at three concentrations, namely 0, 0.3, 0.6 and 1.0%, to improve physical and chemical characteristics of gluten-free cookies. The cookies were subjected to physical and chemical characterization (spread factor, textural properties, gelatinization temperature, enthalpy, color, percent porosity, and crust thickness) and sensory evaluations. The results showed that, the cookies made from extruded sorghum flour (100%) containing Lepidium perfoliatum seed gum at 0.3% had the lowest L* and the highest a* and b* contents. Moreover, the samples composed of non-extruded sorghum flour had the highest adhesiveness and stiffness, while post-baking stiffness of the cookies composed of extruded sorghum flour was lower than those of other cookies; i.e. the cookies made from extruded sorghum flour were of softer texture. These cookies had also the highest spread factor, percent porosity, and crust thickness, and these properties were observed to increase with increasing the gum concentration. Overall acceptability of the cookies made from extruded sorghum flour was significantly higher than those composed of non-extruded sorghum flour, indicating extruded sorghum flour as an appropriate ingredient for producing gluten-free cookies.

Pea starch is a by-product of protein extraction of pea processing. Pea starch is used in industrial applications, but due to the poor functional properties are not used in the food industry. Strach properties can be improved or modified with different methods. The aim of this study was to evaluate the effectt of to modification mehods at two levels 0.05% and 0.07% and acetylation at two levels 6% and 8% on physicochemical, structural and rheological properties of pea starch (Jam variety). The amylose content of native starch was 48.59±0.41 that increased with acytylation reaction but cross-linking reduced this value. Acetylation and substitution degree increased with increasing acetylation degree. Swelling power of cross-linked starch decreased significantly with increasing cross-linking level; but this parameter for acetylated samples were not significantly increased (P>0.05). Syneresis of acetylated starch pastes redced compared to native one; but cross-linking process increased this value compared with native starch. 8% acetylated pea starch with 36.0±1.5 percent significantly had minimum syneresis than other starch samples during storage. In addition, modification of structure of chemically modified pea starch was confirmed by FT-IR. Thermal properties of starches showed that the gelatinization enthalpy of acetylated and cross-linked starch decreased and increased, respectively. Due to the changes of various characteristics of pea starch after chemical modification, the starch samples are expected to have a different functionality compared with native starch.

Nanotechnology applications in food science include enrichment with bioactive substances such as vitamins and phenol compounds and increasing bioavailability of these substances to improve nutritional value of foodstuffs. This study investigated the effect of phospholipid (with 50-100% proportions), cholesterol and beta-sitosterol (each with 0-50% proportions) with seed extracts from black grapes (Vitis Vinifera) (in five levels: 100, 325, 550, 775 and 1000 ppm) on Nanoliposome production via new formulation to trap Vitis Vinifera in a statistical mixeddesign. Nanoliposomes produced in doogh were also added to study their effects alongside phenol compounds on physical stability and chemical properties of doogh. The results of statistical data analysis in a meaningful level (α˂0.05) showed that decrease of consuming extracts and phospholipid to beta-sitosterol ratio resulted in the decrease of Nanoliposome ingredients sizes and phas seperation in doogh samples during the time; it also decreased extracts release from Nanoliposomes and made liposomes more stabled, so releasing decreased in 50:50 formulation and reached 7.9%. Replacing cholesterol with similar healthy substance (Considering results and destructive effects of it on health) would improve public health. Liposome could be an appropriate alternative with regard to positive competences of betasitosterol in new formulation.

One of the oldest processes of cooking all kinds of the foods, such as fish, is deep frying, during which simultaneous transfer of mass and heat leads to water loss and penetration of oil into the foodstuff. The presence of high amounts of fat is one of the negative consequences of this process. The aim of this paper was to evaluate the effects of edible coating (Carboxymethyl Cellulose gum, pectin and protein isolate of zein corn) on the absorption of oil and qualitative properties of salmon fillets under deep frying by two methods of immersion and spraying before frying process. Therefore, Chemical experiments (percent of moisture and fat), measuring the percent of covering, frying efficiency and sensory evaluation were done on the samples. The results show that all the used edible coats lead to the decrease of water loss and consequently, it limits the penetration of oil into the foodstuffs in comparison with control sample. As the results showed, the highest percent of moisture and the lowest amount of oil absorption belonged to the samples covered with pectin 1% by the method of immersion. Moreover, the lowest percent of the moisture and frying efficiency (60.53%) and the highest amount of oil penetration belonged to control sample. The highest amount of covering is related to the sample covered with zein applying immersion metthod. Besides, evaluating the sensory characteristics showed that covering had no negative impact on the sensory characteristics on the fillets.