ARC Industrial Transformation Training Centre for Uniquely Australian Foods, Centre for Nutrition and Food Sciences, Queensland Alliance for Agriculture and Food Innovation (QAAFI), The University of Queensland, Indooroopilly, QLD, Australia.
Commonwealth Scientific and Industrial Research Organization, Agriculture and Food, St Lucia, QLD, Australia.
Food Res Int. 2023 Feb;164:112336. doi: 10.1016/j.foodres.2022.112336. Epub 2022 Dec 20.
Acacia seed (AS) is rich in protein and iron but contains protease inhibitors that can reduce protein digestibility (PD). The seeds are generally roasted prior to consumption, although no information on the PD of roasted AS is available. This study investigated the effect of roasting time (5, 7 and 9 min at 180 °C) on the chemical composition, physicochemical properties, and in vitro PD and intestinal iron absorption of three wild harvested Australian AS species, Acacia victoriae, A. coriacea and A. cowleana. Roasting A. victoriae and A. coriacea seeds for 7 min significantly increased PD in the seeds by 36 and 61 %, respectively. A 9-min roasting time was required to achieve 75 % reduction in trypsin inhibitor activity in A. coriacea seed, while a shorter roasting time (RT) was sufficient to achieve similar reduction rates in the other two Acacia species. Among the functional properties, water and oil absorption capacities were significantly enhanced as RT increased. The starch granules in 7- and 9-min roasted A. victoriae seed flour detached from the protein matrix while random coil increased in 7-min roasted A. victoriae and 9-min roasted A. coriacea and A. cowleana, thus, contributing to enhanced PD. Although the SDS-PAGE in 7- and 9-min roasted A. cowleana samples showed reductions in the intensity of bands for high molecular weight proteins, PD was not affected by RT. However, intestinal iron absorption was not significantly affected by roasting as compared to raw digesta samples. Compared to commercial roasted Acacia seed, the considerably shorter RT used in this study improved PD in the AS flour with less adverse effects on techno-functional properties.
相思豆种子（AS）富含蛋白质和铁，但含有蛋白酶抑制剂，可降低蛋白质消化率（PD）。种子通常在食用前进行烘烤，尽管目前还没有关于烘烤 AS 的 PD 信息。本研究调查了烘烤时间（180°C 下烘烤 5、7 和 9 分钟）对三种野生澳大利亚 AS 物种（Acacia victoriae、A. coriacea 和 A. cowleana）的化学成分、物理化学性质以及体外 PD 和肠道铁吸收的影响。烘烤 A. victoriae 和 A. coriacea 种子 7 分钟可分别使种子 PD 增加 36%和 61%。需要 9 分钟的烘烤时间才能使 A. coriacea 种子中的胰蛋白酶抑制剂活性降低 75%，而在其他两种相思豆中，较短的烘烤时间（RT）就足以达到类似的降低率。在功能特性中，水和油吸收能力随着 RT 的增加而显著增强。7- 和 9-分钟烘烤的 A. victoriae 种子面粉中的淀粉颗粒从蛋白质基质中分离出来，而 7-分钟烘烤的 A. victoriae 和 9-分钟烘烤的 A. coriacea 和 A. cowleana 中随机卷曲增加，从而促进了 PD 的提高。尽管 7-和 9-分钟烘烤的 A. cowleana 样品中的 SDS-PAGE 显示高分子量蛋白质的条带强度降低，但 PD 不受 RT 影响。然而，与生消化物样品相比，肠道铁吸收不受烘烤影响。与商业烘烤的相思豆种子相比，本研究中使用的 RT 短得多，可提高 AS 面粉的 PD，对技术功能特性的不利影响较小。
