Effects Of Spray Drying On Physical Properties, Total Phenolic Content And Antioxidant Activity Of Carob Molasses

Abstract

In the present study carob molasses (pekmez) was spray dried to obtain a powder with desired improved handling properties. Maltodextrin with dextrose equivalent (DE) values of 8.6, 15.3 and 18.6 was used as a drying agent. Different molasses to maltodextrin ratios (25:75, 50:50), and dryer air inlet temperatures (160°C, 210°C) were additional parameters. The spray dried powders were analyzed for glass transition temperature, moisture content, water activity, wetting behavior, particle size, color, total phenolic content and antioxidant activity. The expected increasing effect of decreasing DE value on the glass transition temperature was obscured by different moisture contents. The glass transition temperature was mainly lowered by increasing the pekmez to maltodextrin ratio but also by increasing the air inlet temperature resulting in increasing moisture content. Wetting behavior was strongly influenced by the DE value. Total phenolic content was reduced in general by about 10 % and antioxidant activity changed by about 20 % independent from the investigated parameters. It can be concluded that spray drying of pekmez with addition of maltodextrin is a suitable method to improve and adjust handling properties of pekmez without loss of its nutritional value.

Effect of inlet temperature on physicochemical properties of spray-dried jamun fruit juice powder

“…With an increase in inlet temperature, glass transition temperatures decreased. Similar results were reported by Akkaya et al [22] for spray drying of carob molasses. These T g values were in the same range as those reported for acai powders obtained by spray drying using maltodextrin [25].…”

“…In the first stage, most of the drying occurs as a result of free moisture vaporization from the surface of the droplet. In the second stage, drying rate is lowered as a result of crust formation at the drop surface and the concentration of unbound water to the inner part of the droplet [22]. Especially for sugar-rich products, evaporation is controlled by moisture diffusion in the crust [23].…”

Comparing yields from the extraction of different citrus peels and spray drying of the extracts

“…The average values of TPC 369 retention for all types of citrus extracts were more than 80%. High 370 recoveries of phenolic compounds during spray drying have also 371been reported in several studies[9,28], which suggested that spray 372 drying is suitable for heat-sensitive materials such as phenolic 373 compounds. A previous study has also reported that the spray-374 drying temperatures did not affect the retention of TPC signifi-…”

Effect of Drum Drying on Physico-chemical Characteristics of Dragon Fruit Peel (Hylocereus polyrhizus)

“…A sample cup was half-filled with dragon fruit peel, then the water activity was measured using a pre-calibrated water activity meter (AquaLab, Model CX2, Decagon Devices, Pullman, WA, USA) [16].…”