Crystalline Solution in the System MgO-Mg,SiO4,-MgAl2,O4,

Crystalline solubility relations in the system MgO-Mg₂SiO₄MgAl₂O₄ (periclase-forsterite-spinel) were studied using coprecipitated gels as starting materials. The substitution 2Al = Mg + Si was investigated along the join Mg₂SiO₄-Mg-Al₂O₄,. At 1720°C the maximum crystalline solution in forsterite is about 0.5 mole % MgAI₂O₄, and in spinel it is slightly more than 5.0 mole % Mg₂SiO₄. The solubility of MgO in forsterite was 0.5 mole % at 1860°C, whereas more than 11 mole % Mg₂SiO₄ can be dissolved in the periclase structure at this temperature. Ternary crystalline solution exists in the periclase structure to a composition of Mg_0.853Al_0.063Si_0.026O at 1710°C.     

Physical, Sensory and Microbiological Characteristics of Lamb Retail Cuts Vacuum Packaged in High Oxygen-Barrier Film

Lamb chops and steaks from fresh (F) or vacuum packaged (VP) racks, loins and legs were packaged in polyvinyl chloride (PVC) film or vacuum packaged in high oxygen-barrier (HOB) film. Use of previously vacuum packaged (PVP) cuts did not affect overall appearance of rib or loin chops during subsequent retail display but HOB film-packaged leg steaks from PVP cuts had lower overall appearance scores than did leg steaks from F cuts. Prior VP storage negatively affected flavor desirability and odor at the conclusion of retail display (4 days in PVC or 10 or 15 days in HOB film). Pseudomonas spp. were a dominant part of the microflora of PVC-wrapped chops while L. cellobiosus was a dominant part of the microflora of HOB-wrapped chops.     

PNEUMATIC DRYING IN DILUTED PHASE: PARAMETRIC ANALYSIS OF TUBE DIAMETER AND MEAN PARTICLE DIAMETER

ABSTRACT

In previous work on pneumatic drying presented by the authors, a mathematical model based on the conservation equations of momentum, mass and energy was proposed. This model was developed taking into account axial and radial profiles for gas and solids velocities, pressure and porosity in the drying tube. These dynamic profiles influenced the behavior of temperature in the gas and particulate phases, gas humidity and solids moisture content. In this work, this model has been used to perform a parametric analysis of the tube and panicle diameters in the pneumatic drying process. These variables were analyzed here for fixed conditions of gas and solids flowrates and initial values of temperatures, humidity and moisture content. Factorial planning was applied to the numerical solution of the mathematical model. Experimental data obtained in a pilot scale pneumatic dryer were used as the initial conditions in the simulation to specify the levels of the variables analyzed. Results on the influence of tube diameter and particle diameter on the drying process were obtained by statistical analysis of the responses generated by the factorial planning.     

COMPUTER SIMULATION of CAPACITIVE RADIO FREQUENCY (RF) DIELECTRIC HEATING ON VEGETABLE SPROUT SEEDS

The application of a three‐dimensional finite‐element computer program package, TLM‐FOOD‐HEATING (FAUSTUS Scientific Corp., Victoria, Canada), on the simulation of capacitive radio frequency (RF) dielectric heating of radish and alfalfa seeds was investigated. Seeds placed inside polystyrene boxes were described as a rectangle, where nonuniform boundary conditions presented complications in the simulation. Temperature and moisture dependent thermal properties and temperature and frequency dependent dielectric properties of seeds were considered in the modeling. the time‐temperature profiles of seeds at different locations within the rectangle seeds boxes were simulated. the model was then validated using experimental data. Simulated temperature distribution in seeds was consistent with the measured results. the absolute temperature differences between simulated and measured values in radish seeds packed in a 100 × 25 × 50 mm rectangle seeds box were 1.8C, 1.1C, 8.9C, and 13.6C in the center, top, edge, and bottom locations, respectively, when seeds reached about 80C, and were 0.9C, 2.4C, 7.75C, and 14.3C, respectively, in alfalfa seeds box in the same conditions.     

EFFECT of THERMAL PROCESSING ON THIAMINE RETENTION, IN-VITRO PROTEIN DIGESTIBILITY, ESSENTIAL AMINO ACID COMPOSITION, and SENSORY ATTRIBUTES of PERIWINKLE-BASED FORMULATED LOW ACID FOODS

The effect of thermal processing on thiamine retention, in vitro protein digestibility, amino acid composition, and sensory attributes ofperiwinkle-in- brine (PIB), periwinkle-in-sauce (PIS), and periwinkle-in-egusi soup (PES) with F_o- Values of 4.5, 6.4 and 7.2 mm, respectively, were investigated at pH of 5.8 and temperature range of 104- 121.1C. Thiamine losses were 55.2–7.4%, 64.9–9.7% and 68.5–10.3% for PIB, PIS and PES, respectively, within 104 - 121.1C. Heating resulted in slight decrease in protein digestibility. Methionine losses were 19.0 - 7.8%, 25.2 - 11.4% and 30.8 - 24% in PIB, PIS, and PES, respectively, within 104–121.1C. the flavor appearance and texture of the products improved with increasing temperature and shorter times for commercial sterilization.     

Ozone in dairy chilling water systems: effect on metal materials

The use of pulsed ozone as a disinfecting agent in chilling water systems will be feasible only if components of the systems are not adversely affected. Pulsing ozone into water at room temperature for 20 minutes per day for 7 days caused greater weight loss of aluminium, carbon steel, copper, 304 stainless steel and 316 stainless steel samples than control samples; however, only weight loss for carbon steel was significantly greater (α= .05). Severe pitting was noted on ozone treated copper samples when observed by scanning electron microscopy. Black striations were observed on ozone treated carbon steel surfaces.     

EVALUATION OF A CARBOHYDRATE-BASED FAT REPLACER IN A FAT-REDUCED BAKING POWDER BISCUIT

Three selected carbohydrate-based fat replacers which were derived from pectin, gums, and oat bran (Slendid, Kel-Lite BK and TrimChoice-5, respectively) were used at a fixed rate in biscuits while shortening was reduced at 33, 66 and 100%. The principal effects of each fat substitute on biscuit quality varied with the fat substitute type and level of fat. Generally, fat substitute usage produced a significant (p < 0.05) increase in moisture content, as well as a light crust color. Variations in volume and crumb firmness were associated with the type of fat substitute and level of fat. Sensory data were found to be in agreement with the analytical data for moistness, crust color and crumb firmness. Crumb size decreased and bitterness was detected in biscuits as fat levels decreased regardless of the type of fat substitute.     

Structural and Functional Properties of Caseinate and Whey Protein Isolate as Affected by Temperature and pH

The structural properties, i.e., active sulfhydryl (SH), flexibility and hydrophobicity, and functional properties, i.e., solubility, emulsion activity (EA), emulsion stability (ES), foam overrun (FO) and foam stability (FS), of commercial sodium caseinate (SC) and whey protein isolate (WPI) solutions were investigated at pH 6, 7 and 8 and at 25, 55 and 65°C. WPI contained a higher concentration of active SH and was more hydrophobic than SC. WPI provided comparable solubility and EA, lower FO, but higher FS than SC. Temperature and pH effects on the two proteins were somewhat inconsistent.