Quality Properties and Headspace Volatiles of Hot Air-Dried Strawberries.

Strawberry is one of the most important soft fruit in food industry. With its flavor and antioxidant content, it is widely used mainly in confectionery and beverage industry. Strawberries are perishable and this limits their usage in foods. For that reason, drying is one of the solutions to make them durable. The aim of this study is to analyze certain quality parameters and headspace volatiles of hot air-dried 'Florida Fortuna' and 'Osmanli' strawberries (Fragaria xananassa) at 50, 60 and 70°C. The results showed that drying the strawberry samples at high drying temperature caused a decrease in acidity and bulk density and a deterioration in ascorbic acid content. However, total phenolic contents and total color difference values of both of strawberry samples increased with drying process. A total of 24 headspace volatiles were detected in dried strawberries. The most abundant volatiles were dimethyl sulfide, acetic acid and acetone. The highest number of compound groups were aldehydes, acids, esters and sugar degradation products, respectively. The highest retention of fresh strawberry volatiles and minimum formation of sugar degradation products were obtained by drying at low temperature.

Evaluation of the impact of UV radiation on rheological and textural properties of food.

Demand for healthy, safe, and high-quality foods and disadvantages of thermal processing methods such as quality losses supported the improvement of the novel, affordable, and quick nonthermal food preservation techniques such as UV light. UV-C light (200-280 nm) radiation is an emerging technology for the disinfection of pathogen microorganisms, increasing the shelf life of foods, and used for pasteurization, surface sterilization, cleaning of equipment and water, and so on. Sensory perceptions of foods are effective on the consumer choice, acceptability, and consumption of foods. Rheology term, which also includes texture and mouthfeel, is primarily important for sensory perception, processing of foods, and shelf stability. Therefore, the determination of the effect of different processing methods on the textural and rheological properties of the food products is important. Rheological and textural changes generally occur in the surface of UV-C-irradiated samples due to the low penetration of UV-C light. The UV light treatment may cause internal disruption of cell membranes, which in turn cause loss of turgidity, weaken the cell walls, and contraction of tissues, which are related to the changes in the textural and rheological properties of foods. The present review focuses on the effect of UV-C radiation on the rheology and textural properties of food products.

Advanced osmotic dehydration techniques combined with emerging drying methods for sustainable food production: Impact on bioactive components, texture, color, and sensory properties of food.

The food industries are looking for potential preservation methods for fruits and vegetables. The combination of osmosis and drying has proved the efficient method to improve the food quality. Osmotic dehydration is a mass transfer process in which water molecules from the food move to an osmo-active solution and the solutes from the solution migrate into the food. Advanced osmotic dehydration techniques such as electric field pulse treatment, ultrasonic and microwave-assisted dehydration, pulsed vacuum, and osmodehydrofreezing can improve the nutritional quality (bioactive) and sensory properties (color, texture, aroma, flavor) of fresh and cut-fruits without changing their reliability. Emerging osmotic dehydration technologies can preserve the structure of fruit tissue by forming microscopic channels and increasing effective water diffusivity. However, it is important to analyze the effect of advanced osmotic dehydration techniques on the quality of food products to understand the industrial scalability of these techniques. The present paper discusses the impact of recent osmotic dehydration techniques on bioactive, antioxidant capacity, color, and sensory profile of food.

Mineral content, fatty acid composition, and volatile compounds of gluten-free tarhana formulated with different cereal and pulse flours.

This research was intended to determine the effect of different cereal and pulse flours and commercial gluten-free flour on the mineral content, fatty acid composition, and volatile compounds of the gluten-free tarhana (cereal-based fermented dry soup). In order to produce the gluten-free tarhana, white bean (BF), chickpea (CF), commercial gluten-free (GWF), yellow lentil (LF), and rice (RF) flours were used. The Mg, K, Al, and Mn contents of tarhanas obtained using different pulse and cereal flours were found to be quite high compared to tarhanas produced with commercial GWF. The utilization of different cereal and pulse flours in the tarhana formulation resulted in an increase in the percentage (30.37-51.47%) of the total polyunsaturated fatty acid (TPUFA). The highest (452.4 µg/g) and the lowest (241.17 µg/g) total concentration of all compounds were detected in BF and GWF, respectively. The highest number (21) of compounds belonged to terpenes and terpenoids, followed by acids, hydrocarbons, alcohols, aldehydes, esters, ketones, and alkanes. PRACTICAL APPLICATION: This study shows that cereal and pulse flours can be used to produce acceptable tarhana with improved nutritional quality in terms of mineral and fatty acid contents. The results of the current study may be useful and applicable to food manufacturers producing gluten-free products for celiac patients.

Ultrasound as pretreatment for drying garlic slices in microwave and convective dryer.

The effects of ultrasound pretreatment (US) before hot air drying (HAD) and microwave drying (MWD) of garlic slices were investigated. For this aim ultrasonic bath at 30 °C for 30 min (35 kHz), microwave oven at 540 W power and tray dryer at 60 °C and with 1.0 m/s air flow rate were used to reach the final moisture content of 5%. Drying rate increased in the US + HAD and the US + MWD groups by 19.30% and 13.82% respectively in comparison with control groups. The effective moisture diffusivity (Deff) of garlic slices were calculated from Fick's diffusion model for the HAD, US + HAD, MWD and the US + MWD groups as 1.420 × 10-10, 1.826 × 10-10, 1.177 × 10-8, 1.363 × 10-8 m2/s respectively. The rehydration rates increased, and bulk densities were decreased in the US + HAD and the US + MWD compared to the control groups. The color values were significantly affected after ultrasound pretreatment. Redness, and yellowness increased most in the US + HAD group.