Electron-beam processed corn starch: evaluation of physicochemical and structural properties and technical-economic aspects of the processing

Abstract

The properties of starch can be modified by a variety of methods in order to meet desirable technological needs. Electron beam irradiation is able to induce changes in starch properties. The paper deals with investigation of physicochemical and structural modifications of corn starch processed by electron beam up to 50 kGy and evaluation of the technical-economic aspects of starch processing. Paste viscosity, pasting and peak temperatures decreased in a dose-dependent manner, indicating degradation of the macromolecule. Small circular perforations on the granule surface were observed for 50-kGy irradiated sample. Spectral characteristics suffered minor changes, suggesting that the inter-and intramolecular hydrogen bond stability was affected by the electron beam. These modified starches could find applications in foodstuffs requiring low-viscosity starch. A cost estimate of the electron beam processing of corn starch with an average absorbed dose of 30 kGy showed an increase of corn starch price by 16%.

Heat Transport in Starch Exposed to Ionizing Radiation: Experiment Versus Theoretical Computer Modeling

“…Nowadays, it is well known that radiation processing offers a clean and additive‐free method for the preparation of value‐added novel materials based on renewable, nontoxic, and biodegradable natural polymers . Radiation processing of starch leads indubitably to changes of its functional, physicochemical, and structural properties, making it more suitable than its native form in certain technological uses …”

Aspects on Starches Modified by Ionizing Radiation Processing

“…A gradual decrease of the initial pasting and peak temperatures was also induced by irradiation [3,9,17,19,21,32,33,35,37]. Although the peak time was not influenced by irradiation dose rate, it depended on starch variety [31].…”

“…Several works [3,10,17,21,33,37] have reported results on the crystallinity degree of irradiated starch, estimated by using infrared spectroscopy, which involves the analysis of the absorption bands at 1047 cm −1 (crystalline structure) and 1022 cm −1 (amorphous region), and their respective ratio indicates the degree of starch order. The experimental data revealed that the ratio of 1047/1022 decreased with an increase of gamma radiation dose up to 50 kGy, and the starch granular crystallinity was affected [17,21,33,37].…”

Effect of moisture on technological properties of corn starch modified by the electron beam irradiation

“…Biến tính tinh bột bằng chùm tia electron nhanh chóng, chi phí thấp và thân thiện môi trường mà không có bất kỳ chất gây ô nhiễm, chất xúc tác hay tạo ra sản phẩm dư thừa không mong muốn 4 . Do đó, việc sử dụng tinh bột biến tính bằng chiếu xạ tia điện tử có thể mang đến các cơ hội để phát triển các sản phẩm, làm giảm chi phí chế biến sản phẩm hay tăng thời hạn sử dụng sản phẩm 5 . Độ ẩm là một trong những yếu tố ảnh hưởng đến quá trình chiếu xạ tinh bột thông qua số lượng các gốc tự do hình thành 6,7 .…”

“…Acid formic chiếm hơn 80% số lượng acid carboxylic đối với tinh bột bắp chiếu xạ gamma 24 . Kết quả thu được tương tự với nghiên cứu trên tinh bột bắp 5 , tinh bột cao lương 16 chiếu xạ EB trên 10 kGy. Kết quả nghiên cứu (Bảng 2) cũng cho thấy, ở mức độ ẩm càng thấp, giá trị FA càng cao.…”