MOISTURE SORPTION and VOLUMETRIC CHANGES of CANOLA DURING HYDROTHERMAL PROCESSING

The moisture content and volume change of canola seeds immersed in water or exposed to steam were measured. Three water temperatures of 22, 50 and 75C and one wet steam treatment (atmospheric pressure ∼ 100C) were used in the experiments. the maximum moisture attained by the canola seed was 0.67 decimal (db) in soaking and 0.54 decimal (db) in steaming. the moisture sorption rates were higher at higher temperatures of soaking. the coefficient of expansion did not vary significantly among treatments and an average coefficient of 1.032 per unit change in moisture content was obtained.     

MATHEMATICAL MODELLING of RADIAL CONTINUOUS CROSSFLOW AGRICULTURAL DRYERS

Circular grain dryers in which grainflow is continuous and airflow is in radial direction are widely used as on-farm grain dryers. A concurrentflow drying model is adapted to the crossflow drying of the moving bed of grain. the simulated air and grain temperatures and moisture contents of wheat and corn samples were compared to the experimental drying of these grains in laboratory dryers. the results show that the model can be used to describe temperature of grain within 1°C and moisture content within 0.3% w.b.     

Effect of nitrogen flow ratio on structure and properties of zirconium nitride films on Si(100) prepared by ion beam sputtering

In this study, zirconium nitride thin films were deposited on Si substrates by ion beam sputtering (IBS). Influence of N₂/(N₂+Ar) on the structural and physical properties of the films has been investigated with respect to the atomic ratio between nitrogen and zirconium. It was found that the thickness of layers decreased by increasing the F(N₂). Moreover, crystalline plane peaks such as (111), (200) and (220) with (111) preferred orientation were observed due to strain energy which associate with (111) orientation in ZrN. Also, the fluctuation in nitrogen flow ratio results in colour and electrical resistivity of films.     

Assessment of aflatoxin M1 levels in selected dairy products in north‐western Iran

The purpose of this survey was to evaluate the natural occurrence and content of aflatoxin M_1, AFM_1, in dairy products marketed in Urmia. During September 2007, 40 samples of pasteurised milk, 40 samples of ultra high temperature‐treated (UHT) milk, 40 samples of creamy cheese and 40 samples of Iranian Feta cheese were collected from different supermarkets in Urmia city. AFM₁ contents were determined by the competitive enzyme‐linked imunosorbent assay (ELISA) technique. All milk samples analysed showed a mean of AFM₁ concentrations lower than the permissible level of 50 ng/kg in Iran (23.22 and 19.53 ng/kg in pasteurised milk and UHT milk respectively). The mean levels of AFM₁ contamination were 43.31 ng/kg in Feta cheeses and 21.96 ng/kg in creamy cheeses. The potential risk of human exposure to aflatoxin M₁ via consumption of milk and milk products is well known. Dairy products must therefore be evaluated for aflatoxin and kept free from fungal contamination as much as possible.     

Changes in physicochemical and organoleptic properties of traditional Iranian cheese Lighvan during ripening

Lighvan cheese was studied to determine the physicochemical and biochemical changes over 90 days of ripening in brine. Acidity, pH, dry matter, fat values, lipolysis level, water‐soluble nitrogen (WSN), total nitrogen (TN), ripening index (RI), trichloroacetic acid‐soluble nitrogen (TCA‐SN) and organoleptic assessments were analysed. Dry matter and fat values decreased during ripening. Lipolysis level, RI, TCA‐SN values and salt content increased continuously until the end of the ripening period, but total nitrogen decreased throughout a 90‐day storage period. The ripening stage was the main factor affecting the cheese’s sensory properties.     

QUALITY of ARTIFICIALLY DRIED LENTIL

The effects of artificial drying on Laird lentil qualities such as breakage susceptibility, cooking quality, and seed germination were determined at three initial moisture levels, 16%, 18%, 20% wet basis and seven levels of drying temperature varying from 40°C to 80°C. Cooking quality was not affected by drying in the range of treatments used in this study. High initial Omoisture content and lengthy drying periods at temperatures above 40°C were associated with increased seed breakage. Seed germination was particularly sensitive to heat treatment at 80°C and extended drying time for high moisture samples.