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We present a methodology to predict the storage modulus ( G ’ ) of starch paste due to granule swelling, given the physical properties of the starch granule and temperature history. This was tested on experimental measurements of granule size distribution and G ’ for 8% w/w suspensions of waxy maize, normal maize, waxy rice, normal rice, and cross linked normal maize – all heated to different temperatures (65–90 °C) with holding times between 2 and 60 min. Experimental data of storage modulus G ′ vs volume fraction φ fall onto a master curve when G ′ is normalized by a multiple of γ / R ‾ , where γ is the granule-solvent interfacial energy, and R ‾ is the average granule size. We show that one can combine this master curve with starch swelling theories to forecast the time-dependent rheology of starches. This work also demonstrates that granule-solvent interfacial energy is a key physical parameter in controlling starch rheology.

In this study, we aimed to examine the effects of different low concentrations of alcohol solution (5%–20%) on the gelatinization and pasting properties of pea starch. A rapid visco analyzer revealed that when the starch concentration was fixed, the viscosity of the starch paste decreased with increasing alcohol concentration. In addition, the texture analyzer results showed that compared to the hydrogel formed in water, the hardness of the gel formed by 15% starch in 10% alcohol increased approximately 2-fold (1696.4 g versus 928.1 g). Furthermore, the rheological results showed that the tan δ value of the gel formed under this condition was second only to that of 20% starch in water, which indicated the gel had a strong network structure. X-ray diffraction analysis showed an increased relative crystallinity of 15% starch gels formed in 10% alcohol (13.2%) compared to the hydrogel formed in water (12.2%). Our study will expand the knowledge of the gelatinization properties of starch in low concentrations of alcohol.

In cooking, the functional properties of food hydrocolloids are a valuable means of evaluating the quality of the cooked food and detecting the changes caused in the food properties during the cooking process. The fundamental properties and structure of the hydrocolloid sols and gels are reflected, both directly and indirectly, in the cooking properties. This study focuses mainly on the roles played by various hydrocolloids in cooking. Furthermore, the cooking properties of starch are examined in detail as an example. The subjects of (i) the thermal insulating property of starch paste; (ii) transitions in the properties during the gelation process; and (iii) transitions in the properties of blancmange caused by cooking, etc. are reviewed through rheological experiments and sensory evaluations.