玉米灵芝菌粮营养成分及加工特性变化研究

Study on Changes of Nutritional Components and Processing Characteristics of Ganoderma lucidum Fermented Corn

玉米作为主要的杂粮谷物,营养价值高,维生素、膳食纤维等含量丰富,可以预防多种亚健康疾病,受到市场追捧。但是玉米粉营养结构不均衡、加工性差,限制其应用。有研究表明,微生物发酵技术可以改善谷物的营养成分、大分子物质结构和加工特性。基于此,利用灵芝固态发酵玉米,得到玉米灵芝菌粮(简称菌粮),从营养成分、大分子物质结构和加工特性3个方面对其进行评价。结果显示,与未发酵玉米相比,菌粮中碳水化合物、蛋白质含量分别提高了7.48%、28.00%,且蛋白质的氨基酸评分提高,而脂肪含量降低了52.56%;维生素C、核黄素和烟酸含量均显著提高(P<0.05),分别提高了56.19%、73.91%和20.27%,且玉米中缺乏的硫胺素在菌粮中被检测到;菌粮中各类淀粉和纤维的含量也发生了显著变化(P<0.05),淀粉、支链淀粉含量分别降低了11.17%、34.70%,直链淀粉含量提高了26.66%,粗纤维、不溶性膳食纤维含量分别降低了21.07%、21.47%,可溶性膳食纤维含量提高了13.57%;菌粮粉粘度降低,水溶性指数提高,吸水性指数和溶胀力降低;此外,与灵芝子实体相比,菌粮中灵芝三萜和灵芝酸含量均显著提高(P<0.05),分别为灵芝子实体的1.68和2.07倍。灵芝固态发酵玉米得到的玉米灵芝菌粮,营养结构更加均衡,功能活性提高,具有更高的营养价值;大分子物质结构发生改变,加工特性得到改善,冲调特性更好。研究结果为食用菌发酵改良谷物特性的研究提供了参考和指导。

As the main coarse cereals,corn has high nutritional value,rich in vitamins and dietary fiber,which can prevent a variety of sub-health diseases and is favored by the market.However,the unbalanced nutritional structure and poor processability of corn flour limit its application.Studies have shown that microbial fermentation technology can improve the nutritional composition,macromolecular structure and processing characteristics of grains.Based on this,corn was used as a solid medium fermented by Ganoderma lucidum to obtain the G.lucidum fermented corn(GFC),refer to as fungus fermented cereal(FFC)in this research,and the nutritional composition,macromolecular structure and processing characteristics of FFC were evaluated.The results showed that compared with unfermented corn,the contents of carbohydrate and protein in FFC increased by 7.48%and 28.00%,respectively,and the amino acid score of protein increased,while the fat content decreased by 52.56%.The contents of vitamin C,riboflavin and nicotinic acid increased significantly(P<0.05),by 56.19%,73.91%and 20.27%,respectively,and thiamine,which was deficient in corn,was detected in FFC.The contents of starch and fiber in FFC also changed significantly(P<0.05),starch and amylopectin decreased by 11.17%and 34.70%,amylose increased by 26.66%,crude fiber and insoluble dietary fiber decreased by 21.07%and 21.47%,and soluble dietary fiber increased by 13.57%.The viscosity of FFC powder decreased,the water solubility index increased,and the water absorption index and swelling power decreased.In addition,compared with the fruiting body of G.lucidum,the contents of G.lucidum triterpenes and ganoderic acid in the FFC were significantly increased(P<0.05),which were 1.68 and 2.07 times of those of G.lucidum fruiting body,respectively.The GFC obtained by G.lucidum solid-state fermentation of corn had more balanced nutritional structure,improved functional activity and higher nutritional value.Compared with corn,the macromolecular substances structure of GFC was changed,the processing characteristics were improved,as well as the blending characteristics.The results provided reference and guidance for the study of improving grain characteristics by edible fungi fermentation.