Department of Biology, Federal University of Lavras, Lavras, MG, Brazil.
Daterra Coffee, Patrocinio, MG, Brazil.
Food Res Int. 2017 Feb;92:26-32. doi: 10.1016/j.foodres.2016.12.011. Epub 2016 Dec 23.
Pulped Mundo Novo and Ouro Amarelo coffee beans were inoculated with Saccharomyces cerevisiae (CCMA 0200 and CCMA 0543) during semi-dry coffee fermentation and compared with a non-inoculated control. Samples were collected throughout the fermentation process (12days) to evaluate the persistence of the inoculum by Real-Time quantitative PCR (qPCR). Also, the chemical composition of the beans was determined by HPLC and GC-MS and the roasted beans were sensorial evaluated using the cupping test. S. cerevisiae CCMA 0543 had an average population of 5.6logcell/g (Ouro Amarelo cultivar) and 5.5logcell/g (Mundo Novo cultivar). Citric, malic, succinic and acetic acid were found in all samples, along with sucrose, fructose, and glucose. There were 104 volatile compounds detected: 49 and 55 in green and roasted coffee, respectively. All coffee samples scored over 80 points in the cupping test, indicating they were specialty-grade. Inoculation with the CCMA 0543 strain performed better than the CCMA 0200 strain. This is the first time that qPCR has been used to assess the persistence of the inoculated strains populations during coffee processing. Strain CCMA 0543 was the most suitable as an inoculant due to its enhanced persistence during the process and number of volatile compounds produced.
去皮后的新世界和黄波旁咖啡豆在半干法咖啡发酵过程中接种了酿酒酵母（CCMA 0200 和 CCMA 0543），并与未接种的对照组进行了比较。在发酵过程中（12 天）收集了样本，以通过实时定量 PCR（qPCR）评估接种物的持久性。此外，通过 HPLC 和 GC-MS 确定了咖啡豆的化学成分，并使用杯测法对烘焙后的咖啡豆进行感官评估。酿酒酵母 CCMA 0543 在黄波旁（Ouro Amarelo 品种）和新世界（Mundo Novo 品种）中的平均种群数分别为 5.6logcell/g 和 5.5logcell/g。所有样品中均发现了柠檬酸、苹果酸、琥珀酸和乙酸，以及蔗糖、果糖和葡萄糖。共检测到 104 种挥发性化合物：其中 49 种和 55 种分别存在于绿咖啡豆和烘焙咖啡豆中。所有咖啡样品在杯测中得分均超过 80 分，表明它们是特种咖啡。与 CCMA 0200 菌株相比，接种 CCMA 0543 菌株的效果更好。这是首次使用 qPCR 评估接种菌株在咖啡加工过程中的种群持久性。由于在整个过程中的持续存在和产生的挥发性化合物数量，CCMA 0543 菌株是最适合作为接种物的菌株。
