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Safe storage guidelines based on canola seed moisture content and storage temperature are needed to know how long seed can be held in storage without deterioration. Canola samples with 7.5, 10.0, 12.5 and 15.0% initial moisture content (m.c.) (wet basis) were stored at 10, 20, 30 and 40°C for 16 wk. The seeds retained initial moisture levels at 10°C, while, at 20, 30, and 40°C, the seeds dried during the several weeks of this study. Seed germination, moisture content, appearance of visible mould, free fatty acid value (FAV) and invisible microflora were monitored at regular intervals. Germination of the 7.5 and 10.0% moisture content samples stored at 10 and 20°C remained above 80% throughout the study, whereas that of the other samples dropped over time with higher initial moisture contents and with higher storage temperature. The samples stored at 30 and 40°C lost moisture more rapidly than at 20°C. Visible mould appeared in all the 15.0% moisture content samples and in all the samples stored at 40°C in the early stages of storage. The FAV increased with increasing moisture content, temperature and storage time. Safe storage guidelines were developed for canola with respect to initial moisture content and storage temperature using the measured quality parameters. Canola with <10.0% moisture content stored at <20°C will not deteriorate for at least 15 wk, whereas the 12.5 and 15.0% moisture content seeds stored at >25°C need to be dried within a week to avoid spoilage. [ABSTRACT FROM AUTHOR]

Safe storage guidelines for grains at different moisture contents and storage temperatures are essential to know how long seed can be held without deterioration. Rye samples with 10.0, 12.5, 15.0, and 17.5% moisture content (wet basis) were stored at 10, 20, 30, and 40°C for 16 weeks. Germination, moisture content, visible and invisible microflora, and free fatty acid (FFA) values were monitored periodically. Germination rate decreased significantly with increase in moisture content, temperature, and storage period (α=0.05). Moisture content of the samples stored at 10°C increased with time, whereas that of samples stored at 30 and 40°C decreased. Visible mold appeared in all the 17.5% moisture samples and in all the samples stored at 40°C. Penicillium spp. and Aspergillus glaucus group were the predominant fungi in almost all samples throughout the study. Fat Acidity Value (FAV) increased with increasing moisture content, temperature, and storage time (α=0.05). Safe storage guidelines with respect to initial moisture content and temperature were developed based on the drop in germination and appearance of visible mold. Rye with ≤ 12.5% moisture content stored at ≤ 20°C would be safe for at least 15 weeks, whereas rye with z 15% moisture content stored at 40°C would have less than a week to complete drying and cooling. [ABSTRACT FROM AUTHOR]

Safe storage guidelines for grains at different moisture contents and storage temperatures are essential to know how long seed can be held without deterioration. Rye samples with 10.0, 12.5, 15.0, and 17.5% moisture content (wet basis) were stored at 10, 20, 30, and 40°C for 16 weeks. Germination, moisture content, visible and invisible microflora, and free fatty acid (FFA) values were monitored periodically. Germination rate decreased significantly with increase in moisture content, temperature, and storage period (α=0.05). Moisture content of the samples stored at 10°C increased with time, whereas that of samples stored at 30 and 40°C decreased. Visible mold appeared in all the 17.5% moisture samples and in all the samples stored at 40°C. Penicillium spp. and Aspergillus glaucus group were the predominant fungi in almost all samples throughout the study. Fat Acidity Value (FAV) increased with increasing moisture content, temperature, and storage time (α=0.05). Safe storage guidelines with respect to initial moisture content and temperature were developed based on the drop in germination and appearance of visible mold. Rye with ≤12.5% moisture content stored at ≤20°C would be safe for at least 15 weeks, whereas rye with ≤ 15% moisture content stored at 40°C would have less than a week to complete drying and cooling. [ABSTRACT FROM AUTHOR]

An Alpha MOS FOX- 3000 electronic nose (e-nose) equipped with 12 metal oxide semiconductor (MOS) sensors was used to evaluate the presence of insects in wheat. Samples of Canada western red spring (CWRS) wheat (cv. AC Barrie) infested with rusty grain beetle (RGB), Cryptolestes ferrugineus (Stephens), and red flour beetle (RFB), Tribolium castaneum (Herbst), were placed in glass jars fitted for the collection of headspace volatiles. Different insect densities (0, 1, 2, 10 and 20 insects/kg) were tested for each insect species in combination with three moisture content levels for wheat (14%, 16%, and 18% wet mass basis). The headspace volatiles from insect-infested or non-infested wheat were sampled and injected into the e-nose. The response of e-nose sensors, in the form of a multi-dimensional matrix, was extracted and interpreted using AlphaSoft V8.0 software. The automated pattern recognition algorithms in the software (Principal Component Analysis, Discriminant Factorial Analysis, and Partial Least Square) were used to evaluate the samples. The e-nose could only detect the presence of RFB in wheat with the high infestation level (20 insects/kg) at 14% and 16% moisture content. However, the e-nose did not detect the presence of RFB in wheat at 18% moisture content. The e-nose also failed to detect the presence of RGB in wheat. [ABSTRACT FROM AUTHOR]

Heat treatment to control pest insects in grain processing facilities is becoming more widely used because the fumigant methyl bromide has generally been phased out due to its atmosphere ozone-depleting characteristics. Models with finite difference method, using realistic boundary conditions, were developed to predict the heat and mass transfer that occurred on a concrete floor, in the presence and absence of grain, inside a heattreated building. Temperatures measured every 2 min at 0.5 m below the ceiling and 0.05 m above the bare concrete floor and room relative humidity (RH) were used to model temperature and water loss inside wheat and oats. Temperatures on the surface of the concrete floor and in the grain measured every 2 min during the heat treatment were used to verify and validate the developed models. The maximum and minimum residues between the measured and predicted temperatures of the concrete floors under grain were 3.2°C and -2.8°C, respectively. The larger residues were mostly located at the beginning of the heat treatment. After concrete floor temperatures reached 25°C, the residues between the measured and calculated temperatures of concrete floors under grain were less than ±1°C. These residues were also less than the differences between the temperatures measured in different replicates. The temperature of concrete floor was simulated under the following assumptions: 1) continuous heating of the building for 36 h; and 2) wheat and oats at 11.0, 13.0, or 15.0% moisture contents with 0.01, 0.05, or 0.10 m thickness evenly covering a 0.35 m diameter area on the concrete floor. Simulation results showed that: 1) the temperature of the concrete floor could reach 50°C after 30 h heat treatment; 2) moisture content of the grain could make about 2.5°C difference to the concrete floor temperature; and 3) cleaning before heat treatments should be sufficient to have residues of no more than 0.01 m thick of grain or grain products on floors. [ABSTRACT FROM AUTHOR]

Heat treatment is an effective method of controlling pest insects in grain processing facilities. Temperatures inside a heat-treated flour-storage building and temperatures of wheat, oats, wheat flour, and oat flour in piles or tubes, 0.15 m high, on a concrete floor inside the building, were measured during a 20-h time period of heat treatment. The room temperature at different locations had the same distribution pattern in the vertical direction despite the presence of circulating fans at different locations of the room. Temperature gradients in the vertical direction decreased with increasing height. The maximum and mean temperature gradients above the surface of the concrete floor, in the absence of grain, were 5.4°C/cm and 3.6±0.0°C/cm; respectively. The room temperatures at higher locations varied less than those at lower locations. Moreover, after the surface grain temperature reached 97% of its maximum temperature, it was influenced by the local temperature and periphery configuration. [ABSTRACT FROM AUTHOR]

The major drawback associated with microwave heating is the non-uniform temperature distribution. Temperature distribution studies have shown that various materials behave differently during microwave heating. A pilot-scale industrial microwave dryer operating at 2450 MHz was used to heat grains and oilseed. An infra-red thermal camera was used in this study to determine the temperature distribution in bulk rye and oats at 14, 16, and 18% moisture content (wet basis) and sunflower seeds at 8, 10, and 12% moisture content after being heated in the microwave drier. Fifty grams of grain were placed in a sample holder and allowed to pass on a conveyor belt under the applicator at 0, 200, 300, 400, and 500 W for 28 or 56 s. There were hot and cool regions in the samples. The temperature difference between hot and cool regions in a given sample varied between 23 and 62°C for rye, 7 and 25°C for oats and 7 and 29°C for sunflower seeds. The preliminary results of this study suggest that while using microwave as a heat treatment, the maximum temperature that can affect seed viability (potential to germinate under favorable conditions) should be taken into consideration, when developing microwave processing systems for grains and oilseeds. [ABSTRACT FROM AUTHOR]