本试验旨在研究布氏乳杆菌(LAB)、黑曲霉(AN)、热带假丝酵母(CT)、枯草芽孢杆菌(BS)与植物乳杆菌(LAP)组合对木薯渣品质的影响,筛选出发酵效果最优的混合菌组合。试验以木薯渣为发酵原料,对LAB、AN、CT、BS与LAP进行不同菌种的菌液以1: 1体积比组合,共设5个不同组合,组合1:LAB+AN+CT+LAP;组合2:LAB+AN+BS+LAP;组合3:LAB+CT+BS+LAP;组合4:AN+CT+BS+LAP;组合5:LAB+AN+CT+BS+LAP;各组合分别添加1%尿素或者1%尿素+0.6%红糖,空白组不添加任何添加剂,对照组Ⅰ添加1%尿素;对照组Ⅱ添加1%尿素+0.6%红糖,各组均用生理盐水调制含水量为65%左右,于聚乙烯薄膜袋中真空发酵10 d。结果表明:1)不同微生物添加剂组合发酵木薯渣对木薯渣营养成分改善效果5菌组合优于4菌组合。其中,LAB+AN+CT+BS+LAP+尿素+红糖组合发酵木薯渣效果最好,与空白组相比显著降低了发酵木薯渣pH(P<0.05),提高了乙酸和丙酸含量;中性洗涤纤维(NDF)和酸性洗涤纤维(ADF)含量均为最低,显著低于空白组和对照组(P<0.05);粗蛋白质(CP)含量最高,显著高于空白组和对照组(P<0.05)。2)添加相应的菌种+尿素+红糖发酵木薯渣有利于产生丙酸。3)在发酵培养基中添加尿素能显著提高木薯渣CP含量(P<0.05)。4)在木薯渣发酵过程中添加尿素+红糖比只添加尿素对木薯渣营养成分改善效果好。综上所述,LAB、AN、CT、BS与LAP组合添加尿素和红糖固态发酵木薯渣,可以有效改善木薯渣品质。

The current experiment was carried out to investigate effects of combinations of Lactobasillus buchneri (LAB), Aspergillus niger (AN), Candida tropicalis (CT), Bacillus subtilis (BS) and Lactobacillus plantarum (LAP) on quality of cassava residue, and to find the best strains combination. In this study,cassava residue were used for fermentative raw material, LAB, AN, CT, BS and LAP were combined in accordance with different strains by 1: 1, there were five different combinations in this experiment. Combination 1: LAB+AN+CT+LAP;combination 2: LAB+AN+BS+LAP;combination 3: LAB+CT+BS+LAP; combination 4: AN+CT+BS+LAP; combination 5: LAB+AN+CT+BS+LAP;1% urea or 1% urea+0.6% brown sugar was added to each combination, the blank group was not added any additives, 1% urea was added to the control group Ⅰ, 1% urea+0.6% brown sugar was added to the control group Ⅱ, water content in each group was about 65% by modulating with physiological saline, each group was fermented in the vacuum of polyethylene film bag for 10 days. The results showed as follows: 1) the effects of different microbial inoculants on the nutrition composition of cassava residue, the result showed the combination of LAB+AN+CT+BS+LAP+urea+brown sugar was superior to the four strains combination. The combination 5 get the best quality improvement of cassava residue, compared with the blank group, the pH was significantly reduced (P<0.05), the acetic acid and propionic acid contents were significantly improved (P<0.05), the neutral detergent fiber (NDF) and acid detergent fiber (ADF) contents were the lowest, and significantly lower than those in blank group and control groups (P<0.05), the crude protein content was the highest, and significantly higher than those in blank group and control groups (P<0.05). 2) It was favorable to propionic acid production by adding the corresponding strains+urea+brown sugar to the cassava residue fermented by the mixed strains. 3) When the urea was added into the fermentation medium, the crude protein content in cassava residue was significantly increased (P<0.05). 4) Urea and brown sugar were added into cassava residue for improving the nutrition composition during the fermentation process of cassava residue which was better than that only urea was added into cassava residue. In conclusion, solid-state fermentation using LAB, AN, CT, BS, LAP, urea and brown sugar can offer an effective alternative to improve the quality of cassava residue.