SOLUBILITY, WATER-HOLDING CAPACITY, AND SPECIFIC-GRAVITY OF DIFFERENTCONCENTRATES

The effects of solubility and water-holding capacity on functional and unit specific gravity were evaluated in samples of fish, soybean, lin seed, corn gluten, corn gluten feed, com, barley, and dehydrated alfal fa meals and in wheat bran, raw flaked soybeans, cottonseeds, and drie d sugar beet pulp. Solubility was estimated by washing the samples in nylon bags in a washing machine. Functional specific gravity was estim ated in a pycnometer for unwashed and washed samples after 0 and 15 h of soaking in distilled water. Water-holding capacity was measured by a centrifugation method and by a filtration method. Unit specific grav ity was estimated as the weighted mean of the functional specific grav ity of insoluble DM and the specific gravity of water held by the part icles. Solubility and functional specific gravity of insoluble DM vari ed significantly among feedstuffs from 5.0 to 53.2% of DM and from 1.3 1 to 1.62, respectively. The increase in functional specific gravity f rom soaking was small. Water-holding capacity was lower with filtratio n than with centrifugation methods and varied from .94 to 6.44 g of H2 O/g of DM. Unit specific gravity varied significantly from 1.07 to 1.2 4. Soluble fractions and water-holding capacity can markedly influence the functional and unit specific gravity of concentrate particles.