Penido Fernanda Corrêa Leal, Piló Fernanda Barbosa, Sandes Sávio Henrique de Cicco, Nunes Álvaro Cantini, Colen Gecernir, Oliveira Evelyn de Souza, Rosa Carlos Augusto, Lacerda Inayara Cristina Alves
Universidade Federal de Minas Gerais, Faculdade de Farmácia, Departamento de Alimentos, Belo Horizonte, MG, Brazil.
Universidade Federal de Minas Gerais, Instituto de Ciências Biológicas, Departamento de Microbiologia, Belo Horizonte, MG, Brazil.
Braz J Microbiol. 2018 Oct-Dec;49(4):823-831. doi: 10.1016/j.bjm.2018.02.001. Epub 2018 Feb 28.
Sour cassava starch (Polvilho azedo) is obtained from a spontaneous fermentation conducted by microorganisms from raw materials and fermentation tanks. This product is traditionally used in the baking industry for the manufacture of biscuits and Brazilian cheese breads. However, the end of fermentation is evaluated empirically, and the process occurs without standardization, which results in products of inconsistent quality. Predominant microbiota from a cassava flour manufacturer was isolated in order to select starter cultures for the production of sour cassava starch in a pilot-scale fermentation process. Lactic acid bacteria and yeasts were isolated, enumerated and grouped by Restriction Fragment Length Polymorphism, and PCR fingerprinting, respectively. One isolate of each molecular profile was identified by sequencing of the rRNA gene. LAB were prevalent throughout the entire process. Lactobacillus brevis (21.5%), which produced the highest values of acidity, and Lactobacillus plantarum (13.9%) were among the most frequent species. Pichia scutulata (52.2%) was the prevalent yeast and showed amylolytic activity. The aforementioned species were tested as single and mixed starter cultures in a pilot-scale fermentation process for 28 days. L. plantarum exhibited better performance as a starter culture, which suggests its potential for the production of sour cassava starch.
酸木薯淀粉（Polvilho azedo）是通过微生物对原材料及发酵罐进行自然发酵而获得的。该产品传统上用于烘焙行业，用于制作饼干和巴西奶酪面包。然而，发酵终点是凭经验评估的，且该过程缺乏标准化，导致产品质量参差不齐。为了在中试规模发酵过程中选择用于生产酸木薯淀粉的发酵剂培养物，从一家木薯粉制造商中分离出了优势微生物群。分别通过限制性片段长度多态性分析和PCR指纹图谱技术对乳酸菌和酵母菌进行了分离、计数和分组。通过rRNA基因测序鉴定了每个分子图谱的一个分离株。乳酸菌在整个过程中都很普遍。产酸量最高的短乳杆菌（21.5%）和植物乳杆菌（13.9%）是最常见的种类。盾形毕赤酵母（52.2%）是优势酵母且具有淀粉分解活性。在为期28天的中试规模发酵过程中，对上述菌株作为单一和混合发酵剂培养物进行了测试。植物乳杆菌作为发酵剂培养物表现出更好的性能，这表明其在酸木薯淀粉生产方面具有潜力。
