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Final Moisture Content (final + moisture_content)
Selected AbstractsOptimising microwave vacuum puffing for blue honeysuckle snacksINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 3 2010Chenghai Liu Abstract Fresh blue honeysuckle fruit slices were puffed in a microwave vacuum dryer up to a final moisture content about 5% (w.b.). The effect of initial moisture content (IMC) (25,45%), vacuum pressure (VP) (70,90 kPa) and microwave intensity (MI) (10,30 W g,1) on quality attributes, in terms of expansion ratio (ER), hardness (HD), crispness (CR) and colour of the products, were analysed by response surface methodology. Besides the effect of MI on chroma (CH), the high IMC and low VP had a significantly positive impact on the quality attributes of blue honeysuckle snacks. The optimum product qualities, which were ER (1.62 times), HD (5836.31 g), CR (4.48), and CH (28.7) were obtained at an IMC of 38.42%, VP of 82.02 kPa, and MI of 22.42 W g,1. The microwave vacuum method has obvious advantages when puffing the blue honeysuckle snacks. [source] The glass transition approach to determination of drying protocols for colour stability in dehydrated pear slicesINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 9 2005Hang-Ing Ling Summary Colour stability in dehydrated fruit is often attained by use of sulphite treatment to inhibit browning during processing and storage. However, colour stability may be able to be conferred on products by ensuring that the molecular mobility is restricted in dried fruit by drying to sufficiently low moisture to raise the glass transition temperature (under mild conditions). Pear slices were dehydrated at a low temperature (40 °C) to a low final moisture content (below 5%) after it was shown that, for a moisture content of 22% (which is the moisture content of commercial dehydrated pears) pretreatment with sulphite would be necessary to stabilise the colour. The use of longer drying regimes resulted in a moisture content where the food matrix would be closer to the glassy state and conferred colour stability on the dehydrated product compared to a product containing more moisture. For these low-moisture products, pretreatment with sulphite would not be necessary to preserve colour stability. [source] KINETICS OF ACRYLAMIDE FORMATION DURING TRADITIONAL AND VACUUM FRYING OF POTATO CHIPSJOURNAL OF FOOD PROCESS ENGINEERING, Issue 5 2005CLAUDIA GRANDA ABSTRACT Acrylamide is considered a carcinogen in animals and a possible carcinogen in humans. It has been found in starch-rich foods cooked at high temperatures. Vacuum frying (10 Torr) was investigated as a possible alternative to reduce acrylamide formation in potato chips. The cultivar Atlantic was used to determine the kinetics of acrylamide formation during traditional and vacuum frying at different temperatures. There was a 94% decrease in acrylamide content when potatoes were fried to the same final moisture content (1.5% ± 0.3% w.b.) under vacuum compared to those fried under atmospheric conditions. Acrylamide accumulation under vacuum frying was modeled using first-order kinetics (during traditional frying, the logistic kinetic model was used). The behavior of the kinetics of acrylamide content in potato chips fried under the two processes was different mainly because of the different temperatures used. During traditional frying, higher temperatures are used (150 to 180C) and acrylamide after some time is produced but starts degrading, producing a constant level of acrylamide content at longer times. During vacuum frying (10 Torr), acrylamide increased exponentially (but at lower levels) for all frying times. [source] Improving Grape Quality Using Microwave Vacuum Drying Associated with Temperature ControlJOURNAL OF FOOD SCIENCE, Issue 1 2007C. D. Clary ABSTRACT:, Microwave (MW) vacuum dehydration using temperature to control the level of MW power demonstrated potential in improving the performance of the process. Product surface temperature measured by an infrared temperature sensor was used to control MW power at any level between 0 and 3 kW. Multiple linear regression analysis indicated an r2= 0.942 for prediction of final moisture content and r2= 0.985 for prediction of puffed character of grapes based on product temperature, time, specific energy, fresh fruit sugar, and fresh fruit moisture content. Temperature was found to be the most significant predictor. The elemental and compound contents of grapes dried using MW vacuum was compared to sun-dried raisins. The grapes dried using MW vacuum exhibited better preservation. Vitamin A was found in the MW-vacuum-dried grapes but none was detected in the raisins, and Vitamin C, thiamine, and riboflavin were also higher in the MW-vacuum-dried grapes than in the raisins. [source] Determination of fluidized bed granulation end point using near-infrared spectroscopy and phenomenological analysisJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 3 2005W. Paul Findlay Abstract Simultaneous real-time monitoring of particle size and moisture content by near-infrared spectroscopy through a window into the bed of a fluidized bed granulator is used to determine the granulation end point. The moisture content and particle size determined by the near-infrared monitor correlates well with off-line moisture content and particle size measurements. The measured particle size is modeled using a population balance approach, and the moisture content is shown to follow accepted models during drying. Given a known formulation, with predefined parameters for peak moisture content, final moisture content, and final granule size, the near-infrared monitoring system can be used to control a fluidized bed granulation by determining when binder addition should be stopped and when drying of the granules is complete. © 2005 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 94:604,612, 2005 [source] Polymer aids for settling and filtration of oil sands tailingsTHE CANADIAN JOURNAL OF CHEMICAL ENGINEERING, Issue 3 2010Xiaoyan (Tara) Wang Abstract Commercial Magnafloc 1011 (Percol 727) polymer and in-house synthesised Al-PAM polymer were used to flocculate oil sands tailings that were derived from low and high fines oil sands ores. Fines are defined as mineral solids less than 44,µm. The performance of polymers was evaluated in terms of tailings settling, filtration rate, and final moisture content of tilter cakes. Both polymers were shown to effectively flocculate the derived oil sands tailings and hence to enhance tailings settling. Al-PAM performed very well as a filtration aid. The final moisture content of the filter cake obtained from tailings derived from the low fines ore was 6.6,±,1.2,wt.% and that from the high fines ore was 16.9,±,0.8,wt.%. This class of polymer can provide an alternative approach for oil sands tailings disposal that has the potential to eliminate tailings ponds. However, the commercial Magnafloc 1011 polymer was found ineffective as a filtration aid for the two tailings tested in this study. Le polymère commercial Magnafloc 1011 (Percol 727) et un polymère synthétisé à l'interne Al-PAM ont été utilisés pour floculer des résidus de sables bitumineux dérivés de minerais de sables bitumineux à hautes et faibles concentrations de matériaux fins. Les matériaux fins sont définis comme des solides minéraux de moins de 44,µm. Le rendement des polymères a été évalué en termes de la décantation des résidus, du taux de filtration et du contenu final en humidité des gâteaux des réservoirs à basculement. Les deux polymères ont démontré leur capacité à floculer efficacement les résidus de sables bitumineux dérivés et donc à améliorer la décantation des résidus. Le polymère Al-PAM a produit de très bons résultats comme aide de filtration. Le contenu final en humidité du gâteau de filtre obtenu à partir des résidus dérivés du minerai à faible concentration de matériaux fins était de 6,6,±,1,2 en % de poids et de 16,9,±,0,8 pour le minerai à forte concentration de matériaux. Cette catégorie de polymères peut offrir une approche alternative pour la mise au rebut des résidus de sables bitumineux, alternative qui aurait le potentiel d'éliminer les bassins de décantation de résidus. Cependant, le polymère commercial Magnafloc s'est prouvé inefficace comme aide de filtration pour les deux résidus testés dans cette étude. [source] The Optimisation of Drying Schedules for Pinus radiata Sapwood BoardsASIA-PACIFIC JOURNAL OF CHEMICAL ENGINEERING, Issue 3-4 2004T.A.G. Langrish Optimal drying schedules have been predicted for the drying of Pinus radiata sapwood from an initial moisture content of 140% over a drying time of twenty-four hours for 50mm-thick boards. Initially, a single pair of dry and wet-bulb temperatures (108d,C. 60d,C) over the full time period is estimated to keep the total tangential strain under 50% of the predicted limiting failure value. However, after twelve hours drying, more severe conditions may be used, with the final moisture content predicted to be reduced from 8.2% for a constant set of conditions throughout the schedule (108d,C, 60d,C) to 2.4% when the dry-bulb temperature is raised from 108d,C to 122d,C after twelve hours. It is also possible to use a linearly increasing dry-bulb temperature after twelve hours, rising from 108d,C to 155d,C at the end of drying with a predicted final moisture content of 0.2%. However, to reduce the moisture content to only 10%, there is little difference between the ramped and two-step schedules, both yielding a total drying time of eighteen hours. The two-step schedule would be the easier to in practice. [source] | ||||||||||||||||||||||