Department of Food Science and Nutrition, University of Minnesota, St. Paul, MN 55108, USA.
Molecules. 2024 Sep 9;29(17):4268. doi: 10.3390/molecules29174268.
Intermediate wheatgrass (IWG) is a promising perennial grain explored for mainstream food applications. This study investigated the effects of different germination temperatures (10, 15, and 20 °C) and durations (2, 4, and 6 days) on IWG's volatile and fatty acid (FA) profiles. A method using headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry (HS-SPME-GC-MS) was optimized through response surface design to extract the volatile compounds, achieving ideal extraction conditions at 60 °C for 55 min. Multiple headspace extraction (MHE) was used for volatile compound quantification. Fifty-eight compounds were identified and quantified in IWG flour, mainly alcohols, aldehydes, hydrocarbons, terpenes, esters, organic acids, and ketones. The main FAs found were linoleic acid (C18:2), oleic acid (C18:1), palmitic acid (C16:0), and linolenic acid (C18:3). Principal component analysis showed a direct correlation between volatile oxidation products and FA composition. Germination at 15 °C for 6 days led to a reduced presence of aldehydes and alcohols such as nonanal and 1-pentanol. Therefore, optimized germination was successful in reducing the presence of potential off-odor compounds. This study provides valuable insights into the effects of germination on IWG flour, showing a way for its broader use in food applications.
中间偃麦草（IWG）是一种很有前途的多年生谷物，正在探索用于主流食品应用。本研究调查了不同发芽温度（10、15 和 20°C）和持续时间（2、4 和 6 天）对 IWG 挥发物和脂肪酸（FA）谱的影响。通过响应面设计优化了使用顶空固相微萃取结合气相色谱-质谱法（HS-SPME-GC-MS）的方法来提取挥发物，在 60°C 下达到 55 分钟的理想提取条件。采用多次顶空提取（MHE）对挥发物进行定量。在 IWG 面粉中鉴定和定量了 58 种化合物，主要是醇、醛、烃、萜烯、酯、有机酸和酮。发现的主要 FAs 是亚油酸（C18:2）、油酸（C18:1）、棕榈酸（C16:0）和亚麻酸（C18:3）。主成分分析显示挥发氧化产物与 FA 组成之间存在直接相关性。在 15°C 下发芽 6 天导致醛和醇（如壬醛和 1-戊醇）的存在减少。因此，优化的发芽成功地减少了潜在异味化合物的存在。本研究深入了解了发芽对 IWG 面粉的影响，为其在食品应用中的更广泛应用提供了途径。
