| Resistant starch, a kind of starch that not digested and absorbed by human intestinal, is a great potential functional additives because of the similar physiological functions with dietary fiber but the superior processing characteristics. Previous studies have showed that water holding capacity (WHC) of RS is quite low owing to the crystallization. In this thesis, the effects of RS content on WHC were studied by nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI) technique. The effects of RS on WHC of minced meat and water distribution and internal migration, texture characteristics, sensory quality and water changes during storage in sausages were also investigated while applying RS to the meat products. The results showed that:1. WHC of maize RS is affected by the RS content. The fluidity of water declined with the increased RS content. The effect of the water vs RS ratio on the bound water in samples is significant when it is less than three. In the water absorption process, the strongest bonding between RS and water is decreased due to water infiltration before the water binding capacity of RS has saturated; meanwhile, more water was combined with RS.2. The results from NMR and MRI technique showed that both maize RS and normal corn starch could improve the water-retention properties of minced pork and more or less inhibit the mobility of water. And the optimal content is 4% and 6% for RS and corn starch respectively.3. A very high or low substitution rate of RS could give rise to the reduction of the strongest bounded water in samples, while the amount of free water would increase with the increased RS substitution rate. When the rate is between 40% and 60%, a sausage product containing a fixed amount of starch performed lower hardness and better chewing and flexibility. Nevertheless, the chewiness and cohesiveness of sausages was declined because of RS, but the cohesiveness was considered good when replaced about 60% of starch with RS.4. For the sausage samples, T12 was significantly related to hardness, flexibility and sensory quality. T2*2 and chewiness, cohesiveness was statistically significant related. T11 was also significantly associated with sensory quality and flexibility. It illustrate that water content and its current state are the major factors affecting the sausage texture properties.5. The water movement in sausages was divided into two parts by the changes of proton density, T11 and T12 during the storage time. One is that water in sausages performed a uniform distribution, and the other is that water migrated from the inner center of the sausages to the surface. Moisture migration rate was impacted by the RS substitution rate, which might be due to the changed physical reactions among RS, proteins, fats, and even more original corn starch. The quality change of the sample with different RS substitution rate during storage was evaluated by the mass loss, texture, and MRI imaging. The results showed that the sausages have much better texture qualities, better water retention ability and less weight loss when the RS substitution rate was in range of 40%-60%.
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