Roman Maldonado Yvonne, Villanueva-Rodríguez Socorro Josefina, Hernández-Hernández Hilda María, Terrés Eduardo, Cervantes Martinez Jesus
Food Technology Unit, Center for Research and Assistance in Technology and Design of the State of Jalisco A.C. (CIATEJ), Guadalajara 44270, JAL, Mexico.
Institute of Basic Sciences and Engineering, CONAHCYT-Universidad Autónoma del Estado de Hidalgo (UAEH), Pachuca 42184, HGO, Mexico.
Foods. 2024 Dec 4;13(23):3914. doi: 10.3390/foods13233914.
The red prickly pear fruit ( L. Mill), endemic from Mexico's semi-desert regions and present in North Africa and Southern Europe, particularly Italy and Spain, is a valuable source of nutrients, bioactive compounds, and polysaccharides. This study used non-destructive techniques like microscopy and Raman and infrared (IR) spectroscopy to characterize polysaccharides extracted from two red prickly pear varieties. The polysaccharides constitute approximately 80% of the peel and 39-18% of the pulp; microscopy provided insights into its microstructural details, while Raman and IR spectroscopy enabled the identification of its specific functional groups. The results revealed distinct microstructural attributes: mucilage displays a microstructure influenced by the ratio of acidic to neutral sugar monomers; pectin exhibits a low degree of methoxylation alongside a characteristic egg-box structure facilitated by calcium ions; hemicellulose presents a delicate, porous layer; and cellulose reveals a layered microstructure supported by thin or robust fibers and calcium crystals. The functional groups identified via Raman and IR spectroscopy provided specific information that could be used to infer chemical interactions influenced by functional groups like hydroxyl, carboxyl, and methyl, suggesting potential binding, stabilization, and water retention properties that enhance their utility as functional ingredients in food products. These findings, obtained using non-destructive methods, enhance the understanding of the compositional and microstructural characteristics of polysaccharides in the red prickly pear, which, in turn, can be used to predict their promising technological applications as functional ingredients.
红色仙人掌果（L. Mill）原产于墨西哥的半沙漠地区，在北非和南欧，特别是意大利和西班牙也有分布，是营养物质、生物活性化合物和多糖的宝贵来源。本研究使用显微镜、拉曼光谱和红外（IR）光谱等无损技术对从两个红色仙人掌果品种中提取的多糖进行表征。多糖约占果皮的80%，占果肉的39%-18%；显微镜提供了其微观结构细节的见解，而拉曼光谱和红外光谱则能够识别其特定的官能团。结果揭示了不同的微观结构特征：黏液的微观结构受酸性糖单体与中性糖单体比例的影响；果胶的甲氧基化程度较低，同时具有由钙离子促成的特征性蛋盒结构；半纤维素呈现出一层精致的多孔层；纤维素则显示出由细纤维或粗纤维以及钙晶体支撑的层状微观结构。通过拉曼光谱和红外光谱鉴定出的官能团提供了特定信息，可用于推断受羟基、羧基和甲基等官能团影响的化学相互作用，表明其具有潜在的结合、稳定和保水特性，从而增强了它们作为食品功能成分的效用。这些使用无损方法获得的研究结果，加深了对红色仙人掌果中多糖的组成和微观结构特征的理解，进而可用于预测它们作为功能成分的潜在技术应用。
