Relationship between the corneous and floury endosperm content and the popped sorghum quality

Effects of protein morphological structures on the cereal processing, sensorial property and starch digestion: a review

In cereals, the protein body and protein matrix are usually two morphological protein structures. However, processing treatments can affect protein structures, change protein bodies into the matrix, or induce a change in the matrix structure; therefore, the processing-induced matrix was listed as the third morphological structure of the protein. Previous research on the effect of proteins was mainly based on protein content and composition, but these studies arrived at different conclusions. Studying the effect of protein morphological structures on sensorial property and starch digestion can provide a theoretical basis for selecting cultivars with high sensorial property and help produce low-glycemic index foods for people with diabetes, controlling their postprandial blood sugar. This study aimed to review the distribution and structure of protein bodies, protein matrices, and processing-induced matrices, as well as their influence on cereal sensorial property and starch digestion. Therefore, we determined the protein morphological structures in different cereal cultivars and summarized its impact. Protein bodies mainly have steric stabilization effects on starch gelatinization, whereas the protein matrix serves as a physical barrier surrounding the starch to inhibit water absorption and α-amylase. Processing can change protein morphological structures, enabling protein bodies to act as a physical matrix barrier.

Alternative technologies for the production of popped sorghum: a comparative study

Sorghum is the fifth most harvested crop worldwide, being the popped sorghum as one of the most common snacks in India and some Asian regions. Therefore, this study evaluated how the processing method influences the microstructure, volumetric and textural properties of popped sorghum microstructure, volumetric and textural properties. White sorghum "Paloma" variety (11% moisture) was assessed, which was popped using three processing methods: microwave, pan-frying, and hot salt-frying using three temperature levels. Volumetric and yield characteristics were evaluated for the popped kernels, as their microstructure and texture profile. The popped sorghum obtained through the hot salt-frying method had a microstructure composed of polygonal cells. Also, it showed the best volumetric characteristics (volume), good expansion index, and high process yield. Finally, the hot salt-frying method showed better textural features associated with the attributes of a satisfactory product for consumers.

Structural changes in popped sorghum starch and their impact on the rheological behavior

Sorghum has been used to expand snacks such as pop sorghum. However, it is still unknown how the structural changes during the popping affect its rheological and functional properties. This study evaluated the structural changes of popped sorghum starch (PS) and their impact on rheological behavior. Moisture sorghum was adjusted to 11, 15, and 20% before popped. Morphology, X-ray pattern (XRP), infrared spectra (IR), thermal properties, and rheological behavior before and after popping were evaluated. Micrographs showed a honeycomb-like structure in PS. XRP showed partial damage to the orthorhombic crystals of the sorghum starch after PS, while the growth of crystalline lamellae was also generated (13.08 and 20.01°). IR showed structural damage as the signal at 1045 cm^-1 disappeared in PS. The IM increased to gelatinization of the starch. The rheological behavior of PS displayed better thermal stability, with the lowest breakdown (25 ± 3.5 cP), setback (253 ± 11.3 cP), and final (1337 ± 5.7 cP) viscosity. The consistency coefficient k and flow behavior index n increase, meaning a loss of the pseudoplastic character. Viscoelastic properties increased in PS, suggesting the formation of cross-links and a stable matrix. Correlation analysis showed a strong relationship between structural changes and the rheological behavior of PS.

Impact of the popping process on the structural and thermal properties of sorghum grains (Sorghum bicolor L. Moench)

The popping process has been widely used as a technique for obtaining snacks. This study evaluated the effect of the popping process on the structural and thermal properties of sorghum. Seven varieties of sorghum were used. Raw sorghum grains were adjusted to 11% moisture and popped at 210 °C for 90 s with hot air. Microstructure, thermal and viscosity properties, and X-Ray and infrared spectrum were measured in raw and popped sorghum. The popping process produced an ordered honeycomb-like structure in the sorghum. The viscosity profile showed an increase in the thermal stability of popped sorghum. DSC measurements showed a starch gelatinization and a second transition about to 145 °C. XRD diffractograms display a reduction in the amplitude of the crystalline orthorhombic structure peaks. Finally, infrared indicated a change in the short-range structure and protein denaturation due to the popping process.