جستجوی مقالات مرتبط با کلیدواژه « خصوصیات فیزیکی شیمیایی » در نشریات گروه « صنایع غذایی »

Vegetable oils play an important role in food preparation and food formulation and play a significant role in diet and health. Identification and cultivation of new oilseeds is an important step in the direction of supplying the required oil in the country. Milk thistle plant with the scientific name of Silybum marianum is a one-year or two-year herb that has many medical, medicinal and industrial uses since ancient times. Due to its biological characteristics, this plant requires very little fertilizer and is particularly resistant to dry conditions and weak soils, and it is compatible with the climate conditions of most regions of Iran. Milk thistle seed contains a significant percentage of oil (20-30%) with high nutritional value due to the presence of essential fatty acids such as linoleic acid (40-60%), oleic acid (20-32%) and antioxidant and bioactive compounds such as tocopherols, carotenoids and sterols. Therefore, the oil obtained from milk thistle seed can be considered as a new edible oil due to its long-term consumption in different societies and its bioactive compounds. In this review article, a brief look at milk thistle plant, oil percentage and its composition in different regions has been discussed. According to scientific reports and articles, the cultivation and development of this new and valuable oil seed with good economic value is recommended as a new source of edible oil.

Doogh is a fermented milk drink mixed with water and a little salt. The production and exportation of dough as a native Iranian fermented beverage has grown steadily in recent years. One of the disadvantages that causes corrosion and increases doogh deterioration is the spoilage caused by the activity of molds and yeasts. The common method for increasing shelf life of food (such as doogh) is drying by using spray dryer that eventually lead to reducing the volume, costs of carrying and easy usage. The objective of this study was to produce a doogh powder by spray drying method and investigate the effect of Alyssum homolocarpum seed gum on its physicochemical properties.  In this study, yogurt (1.5% fat), salt, distilled water, maltodextrin (GPC brand), and Alyssum homolocarpum seed gum were used. Alyssum homolocarpum seed gum was cleaned and the foreign particles were separated. The whole grain gum was extracted using distilled water in a water-to-seed ratio of 30 to 1 with a pH of about 8 and a temperature of 48°C and dried at 70°C in a vacuum oven and then powdered. Brine (7% salt) was prepared with boiled distilled water at 80°C. After dissolution, a certain amount of Alyssum homolocarpum seed gum was added (at concentrations of 0, 0.05, 0.1, 0.15, 0.2% separately). The solution was stirred for 10 minutes with a magnetic stirrer at 60°C. After complete dissolution, 40g of yogurt (1.5% fat with pH=4.1) was added to gum solution. The final volume of doogh was at 100g. To completely dissolve the particles, a magnetic stirrer with a speed of 2000 rpm for 15 minutes at 60°C was used. The temperature was then reduced to 20°C and the final product was packed in 500 ml bottles. Doogh was dried using a spray dryer in optimal conditions, feed intake flow of 44.5 ml/ min and drying temperature of 190°C. The physicochemical properties of dough powder such as pH, acidity, moisture content, dry matter, solubility, dispersability, and serum separation as well as glass transition temperature and particle size were determined. Doogh treatments consisted of 0.05, 0.1, 0.15 and 0.2% containing Alyssum homolocarpum seed gum and also a control sample. All the experiments were performen in triplicate. The results were analyzed as means± standard deviation (SD). Thus, the data were determined using the software SPSS (2013). Statistical differences were analyzed by variance (ANOVA) and Duncan’s multiple range test (P values <0.05). The results showed that by increasing the Alyssum homolocarpum seed gum , moisture and serum separation were decreased and  acidity, dry matter, solubility, dispersability ,particle size and glass transition temperature were increased. With increasing gum concentration from 0.05 to 0.1 and from 0.15 to 0.2%, the acidity increased significantly (P<0.05).The rate of dehydration of samples containing different percentages of gum after three weeks showed that the use of Alyssum homolocarpum seed gum significantly reduced serum segregation. The results showed that by increasing the concentration of gum, the particle size of the dough powder was significantly reduced (p<0.05).With the increase in the amount of gum, the rate of diffusion increased significantly (P<0.05).With increasing gum concentration and decreasing moisture, the glass transfer temperature of the powder samples increased. The control sample had the lowest and the 0.2 gum treatment had the highest glass transfer temperature (P<0.05).

Ice cream is one of the most popular dairy desserts in the world. In recent years, the reduction of fat and fiber intake in dietary products has received much attention. Citrus peel is a valuable source of dietary fiber that is usually discarded as waste. In this research, the fiber extracted   from Citrus uranium L. peel was used as a novel fat replacer in light vanilla ice cream.

3 levels of Citrus uranium L.  Fiber (0.5%, 1%, and 1.5%) were added to low fat vanilla ice cream formulation.  The physical, chemical and sensory characteristics of low fat vanilla ice cream were investigated.

The results of this study showed that addition of fiber had a significant effect on the physical properties of ice cream including viscosity and overrun. As the fiber levels increased, the viscosity, melting resistance and overrun of the treatments increased. The effect of fiber on the ice cream pH was significant (P <0.05), with increasing fiber levels, the pH of treatments decreased.Data showed that the effect of citrus uranium L. fiber on all factors of ice cream sensory evaluation was significantly different (P <0.05).Based on the results obtained by increasing the percentage of fiber, the highest score in sensory tests was obtained in treatment 2 (containing 1% fiber). The lowest was for treatment 3 (containing 1.5% fiber).Overall, the results showed that fiber can be used to produce low-fat ice cream with appropriate physico-chemical and sensory properties.Keywords: low fat ice cream, fiber, physico-chemical properties, sensory evaluation.