PHYSICAL BEHAVIOR OF DURUM-WHEAT STARCH (TRITICUM-DURUM) DURING INDUSTRIAL PASTA PROCESSING

Starch was isolated and yields and granule size distributions were det ermined at different steps during industrial pasta production and subs equent high-temperature drying (88 degrees C). The first drying steps rendered the starch granules in general and the small ones in particul ar less extractable, possibly due to increased physical inclusion or i nteraction between starch and gluten components. On the basis of analy tical results, starches were divided in a first group containing those withdrawn before the pasta drier and a second group of starches that have undergone partial or complete drying. The latter starches showed higher gelatinization temperatures and viscosities and lower swelling powers and solubilities during gelatinization. It is suggested that th e high-temperature pasta drying results in less permeable and thus mor e rigid starch granules.