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The objective of this work was to study the influence of spray drying conditions on the physicochemical properties of black mulberry (Morus nigra) powder. A lab-scale spray dryer was employed for the spray drying process and maltodextrin DE=9was used as carrier agent.Response surface methodology (RSM) was performed to examine the effects of independent variables on the drying yield, color change, and total anthocyanin content and to determine the optimum processing conditions. Independent variables were: inlet air temperature (110 ºC, 130 ºC, and 150 ºC), compressed air flow rate (400, 600, and 800 l/h), and maltodextrin concentration (8%, 12%, and 16%). For each response, second order polynomial models were developed using multiple linear regression analysis. Analysis of variance was performed to check the adequacy and accuracy of the fitted models. The optimal conditions for drying yield and total anthocyanin content correspond to: temperature= 130 ºC, maltodextrin concentration= 8%, and compressed air flow rate= 800 L/h; these parameters led to the total anthocyanin content, process yield and browning index values of 5.85 (mg/100mL), 75%, 58.57% respectively.

Electron beam irradiated sliced cantaloupe was tested for 21 d of storage for total aerobic microbial counts, texture, color, and different sensorial parameters as a function of irradiation doses 0, 0.7, and 1.4 kGy and the wash treatments, 1 and 200 ppm chlorine applied to the melons before cutting. Irradiation resulted in a reduction in the total aerobic microbial counts with increasing doses. Melons washed only with water before cutting had total aerobic bacterial counts of 4.0, 2.0, and 0.8 log colony-forming units (CFU)/g on day 0 at irradiation doses of 0, 0.7, and 1.4 kGy, respectively. Across all doses of irradiation, counts were consistently lower for cantaloupe pieces obtained from melons that had been subjected to chlorine rinse in comparison with those washed with water without chlorine. Melons washed with chlorine before cutting had total aerobic bacterial counts of 2.7, 0.7, and 0.5 log CFU/g on day 0 at irradiation doses of 0, 0.7, and 1.4 kGy, respectively. Objective color analysis indicated no significant effect of irradiation on the color of cantaloupe. Texture measured as compression force was lower only for cantaloupe irradiated at 1.4 kGy. Irradiation did not affect descriptive attribute flavor and texture sensory attributes of cantaloupe pieces. Decontamination of whole cantaloupes before cutting using chlorine wash may be combined with low-dose irradiation for shelf-life extension of sliced cantaloupe.

An aqueous solution of Pectinex (containing cellulase, hemicellulase, and pectinase) at 1%, 2.5%, 5%, 7%, and 10% concentrations and 40C was used to extract anthocyanins (Acys) of saffron tepals at 20, 40, 60, 120 and 180 min reaction times and compared with ethanol solvent under similar conditions. The Acys of the Pectinex solution reached 6.7 mg/g of tepal powder (∼40% more than the ethanol method) when the enzyme concentrations and extraction times were, respectively, 5% and 60 min. The Acys of aqueous enzymes had three times slower degradation rates and 50% more attractive chroma color than the ones recovered by ethanol solution after 3 h of extraction time. Additionally, the Acys of the ethanol solution lost its content sharply (>45%) and its chroma changed quickly (due to the browning and polymerization). High performance liquid chromatography (HPLC) analysis showed that Acys extracted with mixed enzymes had about 80% more cyanidin 3-glucosides and 20% less pelargonidin 3,5-glucosides than with the ethanol method. Most probably, the high content of cyanidin 3-glycosides in enzyme-extracted Acys of saffron tepals was the key factor for its high stability.

A b s t r a c t. Physical properties ie dimensions, volume, surface area, sphericity, true density, porosity, angle of repose, terminal velocity, static and dynamic friction coefficients on plywood, stainless steel, glass and galvanized iron sheet, force required for initiating seed rupture in horizontal and vertical orientations of psyllium seed at a moisture content of 7.2% (w.b.) were determined.K e y w o r d s: psyllium seed, physical properties, postharvest technology INTRODUCTION Psyllium (Plantago ovata Forsk) is an annual plant, cultivated mainly in India. Also, psyllium seed is called Isabgol, meaning 'horse ear' in Indian, which explains the shape of the seed. India dominates the world market in the production and export of psyllium, producing around 39 000 t of psyllium seed every year and providing 85% of psyllium seed to the world market. The mechanical milling/grinding of the outer layer of psyllium seeds (seed coat) provides the main raw material for commercial production of mucilage. Mucilage is a white fibrous hydrophilic material and forms the clear coluorless mucilaginous gel by absorbing water. The extracted gel nature of psyllium seeds has a medicinally active natural polysaccharide composition (Guo et al., 2009).In order to design proper equipment for the processing, transportation, sorting, separation and storing of psyllium, it is necessary to have reliable information regarding the physical properties of this seed. Designing seed processing equipment without considering engineering specifications of proposed seed may yield poor results (Davies and ElOkene, 2009). Since there is not enough information on the physico-mechanical properties of psyllium seed.The aim of this investigation was to measure physical properties of psyllium seed at a moisture content of 7.2%. MATERIALS AND METHODSSeeds of psyllium were used for all the various experiments in this study (Fig. 1). The seeds were obtained from the local market during September-October, 2009 in Karaj and transported to the laboratory in cooled condition. After removing all foreign matter such as dust, dirt, stones and chaff, as well as immature and broken seeds, the initial moisture content of the seeds was determined by oven drying at 105 ±1°C for 24 h (AOAC, 1990). All the physical and mechanical properties of the seeds were assessed at this moisture (7.2% w.b.). To determine the average size of psyllium, 100 seeds were randomly picked and their three linear dimensions, namely, length, width and thickness, were measured using a digital vernier caliper (SV-03 model, Taiwan) with an accuracy of 0.01 mm. The arithmetic (D a ) and geometric (D g ) mean diameter, sphericity, surface area of psyllium seeds were calculated according to Mohsenin (1986). An electronic balance (Mettler Toledo AT261) with a reading precision of 10 ìg was used to determine the mass of psyllium seeds. Bulk density or the ratio of grain mass to the maximum volume (including free and membrane air) of Int. Agrophys., 2012, 26, 91-93