BRUISING AND SPLITTING OF APPLE FRUIT UNDER UNI-AXIAL COMPRESSION AND THE ROLE OF SKIN IN PREVENTING DAMAGE

Whole apples were compressed uni-axially with the core at right angles (horizontal compression) and parallel (vertical compression) to the direction of force. Under horizontal compression, the apple begins to bruise as soon as force is applied. The energy absorbed is proportional to the volume of bruise produced. Resistance to bruising varies with variety. In this orientation the fruit does not deform elastically, bruises easily, and the skin is not important in preventing bruising. Under vertical compression the apple is a much more elastic structure and can expand laterally. It can withstand greater deformation without damage. Rock Pippin can elastically absorb up to 0.5 J before damage. In this orientation, skin plays an important part in preventing cracking under tension. Any damage to the skin greatly reduces the structural strength of the fruit and renders it much more susceptible to cracking. Apples stacked in boxes seldom experience energies greater than 0.5 J. Storing apples in a vertical orientation can therefore reduce risk of bruising.     

Feed Moisture Effects on Functional Properties, Trypsin Inhibitor and Hemagglutinating Activities of Extruded Bean High Starch Fractions

High starch fractions (HSF) of navy, pinto and garbanzo beans were extruded with different moisture contents using a Wenger X-5 extruder. Increasing moisture content resulted in increased expansion index for navy and garbanzo beans and a decrease for pinto bean. The highest water absorption index was obtained for navy bean HSF at moisture 27%, for pinto 30% and for garbanzo 26%. For all beans, water solubility index decreased with increasing moisture. Color of extrudates also was affected by moisture. The extrusion process reduced trypsin inhibitor activity by about 70–85%, the level of decrease determined by moisture content of starting material and temperature. Extrusion temperatures of 121, 132 and 150°C inactivated hemagglutinating activity of navy, pinto and garbanzo beans.     

Enzyme—Pretreatment of Pinto Bean High Protein Fraction and Time of Blending Corn Meal Affects Extrudate Properties

High protein fraction of pinto bean, treated with papain and cellulose enzymes (Solvay Enzymes Inc.), was blended with corn meal (30%) and extruded at 120°C. Changes in expansion, texture, color, pH, in vitro protein digestibility, reducing sugars and functional properties of extmdates were recorded. Changes depended on type of enzymes and time of corn incorporation (before or after enzymatic pretreatment). The best texture of the extrudates was obtained using a cellulase enzyme. Papain affected some functional properties such as NSI and WSI. The best improvement in in vitro protein digestibility and reducing sugars was found with a cellulase treatment. Protein and fiber could be modified to improve physicochemical and functional properties of extrudates.     

Synthesis of high-speed tool steel surfaces on mild steel

Wear-resistant, hard surfaces of high-speed tool steel were synthesized on mild steel specimens. Discs of mild steel were subjected to carburization to a depth of 2.5 mm. Thin strips of tungsten were spot welded and the specimen was subjected to electron beam surface melting. The beam power was varied from 60 kV, 10 mA to 60 kV, 20 mA. Oscillation frequency and the specimen translation velocity were kept at 1000 Hz and 2 cm s-1, respectively. The width of the modified layer was 10 mm while the depth varied from 0.7–2.3 mm. A concentration of up to 30 wt% tungsten could be achieved in the surface layer by varying the thickness of the foil spot welded prior to electron-beam melting. Tungsten concentration was uniform along the depth. The hardness achieved in the as-solidified layer was uniform along the depth and reached 800 Hv. The reprocessing of the alloyed layer with the beam promoted fine carbide precipitation which then resulted in refinement of martensite plates.     

Quality attributes of four rice varieties

The physico-chemical characteristics, and cooking, eating, milling and nutritive qualities of four varities of rice were measured and wide varietal differences were observed.
There was little variation in gel consistency and gelatinization temperature, but there were marked differences in water absorption, volume expansion and percentage of leach loss.
Eating characteristics of one variety (Ambemohar) were less acceptable than in the other three, and one (MAU-Sel-9) had a much higher protein content than the others.
On the whole, the quality of MAU-Sel-9 was found to be superior to the other three varieties of rice.