Departamento de Química, Biotecnologia e Engenharia de Bioprocessos, Universidade Federal de São João del-Rei, Campus Alto Paraopeba, MG 443, km 7, 36420-000 Ouro Branco, MG, Brazil; Departamento de Tecnologia de Alimentos, Universidade Federal de Viçosa (UFV), Av.P. H. Rolfs, s/n, 36570-000 Viçosa, MG, Brazil.
Departamento de Tecnologia de Alimentos, Universidade Federal de Viçosa (UFV), Av.P. H. Rolfs, s/n, 36570-000 Viçosa, MG, Brazil; Departamento de Ingeniería de Alimentos, Universidad de Córdoba, Cra 6(a) N°- 76 - 103 Montería, Córdoba, Colombia.
Food Res Int. 2019 Feb;116:492-498. doi: 10.1016/j.foodres.2018.08.065. Epub 2018 Aug 21.
Conjugates of protein (α-lactalbumin, β-lactoglobulin, and lysozyme) with polysaccharides (guar, locust, pectin, and carboxymethilcellulose) were prepared via Maillard reaction by the dry-heating method. The conjugates were characterizated by using the browning index, extent of reaction, grafting degree, sodium dodecyl sulfate - polyacrilamide gel electrophoresis, fluorescence, and circular dichroism. The emulsifying properties and foaming ability of the formed conjugates were also evaluated. Conjugates with pectin and Lz-CMC system showed an increase in the browning index with the increase of the heating time. Circular dichroism and fluorescence data pointed out to conformational changes of proteins during glycation. The lysozyme (lz) conjugates presented the highest degree of glycation (89.1%). The α-Lactalbumin (α-la) - polysaccharides (PS) conjugates showed foam stability higher than the mixture (α-la + PS), the pure α-la, and the conjugates of β-lactoglobulin (β-lg) and lysozyme (lz) for all studied time (30, 60, and 120 min). The α-la-carboxymethylcellulose (CMC) conjugate presented the highest value of foaming stability (85.71). The pure β-lg shows greater foam stability and volume than β-lg-PS conjugates and mixture (β-lg + PS). The lz conjugates do not exihibit foam stability, except for the lz-CMC conjugate that showed stability up to 60 min. Furthermore, emulsion stability of the systems was affected by sonication time. Conjugates of α-la have greatly potencial applications as novel foaming agents in food industry.
通过干热法的美拉德反应，将蛋白质（α-乳白蛋白、β-乳球蛋白和溶菌酶）与多糖（瓜尔胶、槐豆胶、果胶和羧甲基纤维素）制备成缀合物。通过褐变指数、反应程度、接枝度、十二烷基硫酸钠-聚丙烯酰胺凝胶电泳、荧光和圆二色性对缀合物进行了表征。还评估了形成的缀合物的乳化性能和起泡能力。随着加热时间的增加，果胶和 Lz-CMC 系统的缀合物的褐变指数增加。圆二色性和荧光数据表明蛋白质在糖化过程中构象发生了变化。溶菌酶（lz）缀合物的糖化程度最高（89.1%）。α-乳白蛋白（α-la）-多糖（PS）缀合物的泡沫稳定性高于混合物（α-la+PS）、纯α-la 以及所有研究时间（30、60 和 120 分钟）的β-乳球蛋白（β-lg）和溶菌酶（lz）的缀合物。α-la-羧甲基纤维素（CMC）缀合物的泡沫稳定性最高（85.71%）。纯β-lg 的泡沫稳定性和体积大于β-lg-PS 缀合物和混合物（β-lg+PS）。除了 lz-CMC 缀合物在 60 分钟内保持稳定外，lz 缀合物没有表现出泡沫稳定性。此外，系统的乳化稳定性受到超声时间的影响。α-la 缀合物具有作为食品工业新型起泡剂的巨大应用潜力。
