Liao Hung-Ju, Hung Chih-Chiao
Department of Food Science, National Chiayi University, No. 300 Syuefu Road, Chiayi City, 600355, Taiwan, Republic of China.
Plant Foods Hum Nutr. 2023 Mar;78(1):52-60. doi: 10.1007/s11130-022-01021-x. Epub 2022 Oct 27.
Green banana fruit with high resistant starch (RS) content has a potential to be a nutraceutical ingredient despite having an unpleasant astringency taste and is yet to be fully explored. In this study, the green banana after de-astringency treatment was employed for flour production, and the resulting flour was subjected to modification by the combined treatments of pullulanase debranching and annealing. The banana flour (BF) and the modified flour (MF) were compared with each other by evaluating their functional, thermal and structural properties. The BF showed a restricted-swelling pasting profile, behaving like a slightly chemically cross-linked starch; the MF exhibited less pronounced changes in pasting behavior with increased solubility and decreased swelling power and dispersed volume fraction at elevated temperatures. As compared with the BF, an enhanced thermal stability of the MF was observed, reflected in the endotherm shifting to higher temperatures with increased enthalpy. The BF displayed a C-type polymorph, while the MF comprised a mixture of B- and V-type polymorphs with increased crystallinity. The MF showed an increased molecular order, reflected in an increase in short-range double helical order detected in the starch fingerprint regions of FT-IR spectra, and along with increased crystallinity, underlying its enhanced thermal stability. The modification treatment resulted in irregularly shaped flour particles with a more compact structure as revealed by morphological characters. The results of this study can provide useful information for the development of food products using the modified green banana flour with improved thermal stability and functional properties as a health-promoting ingredient.
尽管青香蕉果实含有高抗性淀粉（RS），但因其具有令人不悦的涩味，作为营养成分的潜力尚未得到充分探索。在本研究中，经过脱涩处理的青香蕉被用于制作面粉，所得面粉经过普鲁兰酶脱支和退火的联合处理进行改性。通过评估香蕉面粉（BF）和改性面粉（MF）的功能、热学和结构性质对二者进行比较。BF呈现出受限膨胀的糊化特性，表现得像轻度化学交联淀粉；MF在糊化行为上变化不那么明显，在高温下溶解度增加，膨胀力和分散体积分数降低。与BF相比，观察到MF的热稳定性增强，表现为吸热峰向更高温度移动且焓增加。BF呈现C型多晶型，而MF包含B型和V型多晶型的混合物且结晶度增加。MF的分子有序度增加，这反映在傅里叶变换红外光谱淀粉指纹区检测到的短程双螺旋有序度增加，并且随着结晶度增加，这是其热稳定性增强的基础。形态特征显示，改性处理导致面粉颗粒形状不规则且结构更致密。本研究结果可为开发以具有改善热稳定性和功能特性的改性青香蕉面粉作为促进健康成分的食品提供有用信息。
