Laboratório de Química e Bioatividade de Alimentos e Núcleo de Pesquisa em Café (NUPECAFÉ), Instituto de Nutrição, Universidade Federal do Rio de Janeiro, Avenida Carlos Chagas Filho, 373, CCS, Bl. J, Rio de Janeiro 21941-902, Brazil.
LAQV-REQUIMTE, Laboratório de Bromatologia e Hidrologia, Faculdade de Farmácia, Universidadedo Porto, R. Jorge de Viterbo Ferreira 228, 4050-313 Porto, Portugal.
Food Res Int. 2024 Jun;186:114333. doi: 10.1016/j.foodres.2024.114333. Epub 2024 Apr 18.
Acrylamide is an amide formed in the Maillard reaction, with asparagine as the primary amino acid precursor. The intake of large amounts of acrylamide has induced genotoxic and carcinogenic effects in hormone-sensitive tissues of animals. The enzime asparaginase is one of the most effective methods for lowering the formation of acrylamide in foods such as potatoes. However, the reported sensory outcomes for coffee have been unsatisfactory so far. This study aimed to produce coffees with reduced levels of acrylamide by treating them with asparaginase while retaining their original sensory and bioactive profiles. Three raw samples of Coffea arabica, including two specialty coffees, and one of Coffea canephora were treated with 1000, 2000, and 3000 ASNU of the enzyme. Asparagine and bioactive compounds (chlorogenic acids-CGA, caffeine, and trigonelline) were quantified in raw and roasted beans by HPLC and LC-MS, while the determination of acrylamide and volatile organic compounds was performed in roasted beans by CG-MS. Soluble solids, titratable acidity, and pH were also determined. Professional cupping by Q-graders and consumer sensory tests were also conducted. Results were analyzed by ANOVA-Fisher, MFA, PCA and Cluster analyses, with significance levels set at p ≤ 0.05. Steam treatment alone decreased acrylamide content by 18.4%, on average, and 6.1% in medium roasted arabica and canefora coffees. Average reductions of 32.5-56.0% in acrylamide formation were observed in medium roasted arabica beans when 1000-3000 ASNU were applied. In the canefora sample, 59.4-60.7% reductions were observed. However, steam treatment primarily caused 17.1-26.7% reduction of total CGA and lactones in medium roasted arabica samples and 13.9-22.0% in canefora sample, while changes in trigonelline, caffeine, and other evaluated chemical parameters, including the volatile profiles were minimal. Increasing enzyme loads slightly elevated acidity. The only sensory changes observed by Q-graders and or consumers in treated samples were a modest increase in acidity when 3000 ASNU was used in the sample with lower acidity, loss of mild off-notes in control samples, and increased perception of sensory descriptors. The former was selected given the similarity in chemical outcomes among beans treated with 2000 and 3000 ASNU loads.
丙烯酰胺是美拉德反应中形成的酰胺，以天冬酰胺为主要氨基酸前体。大量摄入丙烯酰胺会在动物的激素敏感组织中引起遗传毒性和致癌作用。天冬酰胺酶是降低马铃薯等食品中丙烯酰胺形成的最有效方法之一。然而，迄今为止，报道的咖啡感官结果并不令人满意。本研究旨在通过用天冬酰胺酶处理咖啡来生产丙烯酰胺含量降低的咖啡，同时保留其原始的感官和生物活性特征。处理了三种阿拉比卡咖啡的生咖啡豆样本，包括两种特种咖啡和一种罗布斯塔咖啡，酶用量分别为 1000、2000 和 3000 ASNU。通过高效液相色谱法和 LC-MS 定量测定生豆和烘焙豆中天冬酰胺和生物活性化合物（绿原酸-CGA、咖啡因和葫芦巴碱），通过 CG-MS 测定烘焙豆中的丙烯酰胺和挥发性有机化合物。还测定了可溶性固形物、可滴定酸度和 pH 值。由 Q-分级师进行专业品尝和消费者感官测试。使用方差分析-Fisher、MFA、PCA 和聚类分析对结果进行分析，置信水平设置为 p≤0.05。单独的蒸汽处理平均降低了 18.4%的丙烯酰胺含量，在中烘焙阿拉比卡和罗布斯塔咖啡中降低了 6.1%。在中烘焙阿拉比卡咖啡豆中，当使用 1000-3000 ASNU 时，丙烯酰胺形成的平均减少率为 32.5-56.0%。在罗布斯塔样本中，观察到 59.4-60.7%的减少。然而，蒸汽处理主要导致中烘焙阿拉比卡样品中天冬酰胺和内酯的总 CGA 减少 17.1-26.7%，罗布斯塔样品减少 13.9-22.0%，而葫芦巴碱、咖啡因和其他评估的化学参数的变化很小，包括挥发性特征。增加酶负荷会略微提高酸度。Q-分级师和/或消费者在处理过的样品中观察到的唯一感官变化是，当在酸度较低的样品中使用 3000 ASNU 时，酸度略有增加，对照样品中轻微的异味丧失，以及对感官描述符的感知增加。由于用 2000 和 3000 ASNU 负载处理的咖啡豆在化学结果上具有相似性，因此选择了前者。
