摘要
废酵母是啤酒生产过程中的副产物,约占啤酒产量的2%～3%。在当前资源短缺,环境污染严重的现状下,对废酵母进行开发利用,对减轻废酵母的环境污染,增加啤酒行业效益有重要的意义。目前,酵母的加工方法主要是将酵母泥直接烘干,或用压滤机对酵母进行分离,然后对分离出的酵母进行干燥,生产商品酵母粉。但在酵母的干燥过程中会产生大量的废蒸汽,其中含有4.5%左右的酒精,排放到空气中,既污染了环境,又造成了资源浪费,尚未引起企业的重视。
针对这种现状,本课题的目的就是要回收利用这部分酒精资源,并以回收的酒精为原料采用醋酸液态深层发酵与萃取-蒸馏工艺或共沸精馏工艺相结合生产高酸醋,此产品可用于食品与化妆品行业,具有广泛的应用前景。本课题的内容和结果如下:
1.列管式换热器冷凝、吸收塔吸收回收酒精。
采用适当型号的列管式换热器和吸收塔回收酒精,回收率达到90%左右。回收的酒精溶液经连续蒸馏塔蒸馏去杂,得到的酒精经检测,符合食用酒精标准,可作为醋酸发酵产酸的原料。
2.以酒精为原料添加废酵母自溶液发酵产酸。
在以酒精为原料发酵产酸的过程中,为了维持正常的醋酸发酵需添加少量含碳、氮源的营养液。本课题通过实验确定了废酵母自溶液的最佳制备工艺及以酒精为原料发酵产酸的工艺配方,探索了采用廉价的废酵母自溶液作为有机氮源进行醋酸发酵的可行性。结果表明,以废酵母自溶液作为醋酸发酵的有机氮源是可行的。当以自溶液为有机氮源替代酵母浸粉时,醋酸菌浓度的提高超过54%,醋酸含量的提高超过10%。自溶液的最佳制备工艺为:加水量200%,初始pH值7.0,自溶温度50℃,时间48h,食盐优化用量3%。以酒精为原料发酵产酸的最佳配方为:酒精浓度5%,酵母液添加量13%,菌种接种量12%。
3.萃取-蒸馏或共沸精馏生产高酸醋。
结果表明,通过萃取-蒸馏或共沸精馏可以生产出25%左右的高酸醋,达到了课题的目标要求。萃取-蒸馏时,采用乙酸乙酯作为萃取剂,萃取时间为20min,最佳溶剂比为1.0,三级错流萃取后,水相中的醋酸浓度为0.79g/100mL,达到目标要求。共沸精馏时,采用乙酸丁酯作为共沸剂;随着共沸剂含量的增加,塔釜醋酸浓度逐渐增加,但随着共沸剂含量的进一步增加,醋酸浓度下降,而塔顶醋酸浓度均控制在一个比较小的范围内;水与共沸剂的配比固定时,随着样品醋酸浓度的增加,塔釜醋酸浓度增加;共沸剂的平均回收率为95.33%,损失较少,基本可以回收重复利用。
The waste yeast is the by-product during the brewing process, accounting for approximately 2%～3% of the total beer output. Under the status of resources shortage and serious environment pollution, it is necessary to develop and explore the waste yeast to reduce pollution and increase benefits of beer industry. Now, the yeast is mainly dried directly, or filtered to be separated and then the separated yeast is dried. However, a lot of waste steam will produce in the process of yeast drying, which contains 4.5% alcohol. If the waste steam releases into the air, not only the environment is polluted, but also the resources are wasted. Enterprises have not yet aroused the attention.
In view of this situation, the purpose of this paper is to utilize the alcohol resources and produce high sour vinegar using the alcohol as material and using the submerged fermentation and extraction-distillation process, or azeotropic distillation process as method. This product can be used in food and cosmetic industries, which has a broad application prospect. The contents and results are as follows:
1. Alcohol recovery using tubular heat exchanger and packed absorption tower
The recovery ratio was about 90% adopting appropriate models of tubular heat exchanger and packed absorption tower. The recoverable alcohol solution was distilled to remove impurities using continuous distillation column. Through detecting, the distilled alcohol accorded with the edible alcohol standard. And it was feasible to produce acetic acid using the alcohol.
2. Acetic fermentation using alcohol as material adding yeast autolysis solution
In the process of acetic fermentation using alcohol as material, a small amount of nutrient solution containing carbon and nitrogen was added in order to maintain normal acetic fermentation. The optimal preparation technology of yeast autolysis solution and the formulation of acetic fermentation using alcohol as material were established through experiments. A new kind of organic nitrogen, yeast autolysis solution, was attempted to be used during the process of acetic acid fermentation. The results indicated that it was feasible to use yeast autolysis solution as organic nitrogen in the process of acetic acid fermentation. The concentration of acetic acid bacteria and acetic acid were improved more than 54% and 10%, respectively, when yeast autolysis solution was used instead of yeast extract. The optimal preparation technology of yeast autolysis solution solution was as follows: water 200%, initial pH 7.0, autolysis temperature 50℃, autolysis time 48h and NaCl 3%. The optimal formulation of acetic acid fermentation was as follows: 5% alcohol, 13% yeast autolysis solution, 12% inoculum.
3. High sour vinegar production using extraction-distillation or azeotropic distillation as method
Test results indicated that 25% high sour vinegar could be produced, which achieved the objective and requirement of the subject, through extraction-distillation or zeotropic distillation. In the process of extraction-distillation, acetic ether was used as extration solvent and the optimal technology for the production of high sour vinegar was as follows: 20 minutes extraction, 1.0 proportion of solvent. The acid concentration in the water was 0.79g/100mL, which met the requirement, through three cross-flow extractions. In the process of azeotropic distillation, butyl acetate was used as azeotropic agent. With the increase of the azeotropic agent’s content, acid concentration of Still Pot gradually increased. But with a further increase of azeotropic agent’s content, the acid concentration decreased. The acid concentration of tower’s top was controlled in a relatively small area. When the ratio of water to azeotropic agent was fixed, with the increase of acid concentration of sample, acid concentration of Still Pot increased. The average recovery rate of azeotropic agent was 95.33% and the azeotropic agent could be reused.
引文
[1] 孔明, 姚淑华. 啤酒废酵母综合利用的探讨[J]. 广州食品科技, 2003, 19(2): 59-63
[2] 李彦. 利用啤酒废酵母泥生产营养酸奶[J]. 包装与食品机械, 2002, 22(5): 33-35
[3] 吴思芳. 啤酒废酵母生产酵母味素的研究[J]. 食品科学, 2000, (6): 21-22
[4] 张帅, 王秀道. 从啤酒废酵母中制备酵母抽提物[J]. 食品工业科技, 2002, (9): 50-51
[5] 周红卫, 江林. 啤酒废酵母的回收利用[J]. 江苏调味副食品, 2000, (1): 12-13
[6] 胡根河, 王中良. 利用啤酒废酵母生产酱油[J]. 江苏调味副食品, 2003, (1): 23-24
[7] 刘烺新, 陈宗道, 王光慈. 啤酒酵母胞壁多糖提取工艺的研究[J]. 重庆大学学报, 1994, 17(6): 43-48
[8] 张玉香, 尹卓容. 甘露糖蛋白的提纯及分子量测定[J]. 酿酒科技, 2005, (4): 72-74
[9] 明景熙. 从啤酒废酵母中提取 SOD 的几种工艺方法[J]. 中国酿造, 2003, (4): 7-9
[10] 齐香君, 刘树兴, 丁秀英, 等. 啤酒废酵母生产果糖磷酸钠[J]. 酿酒, 2002, 29(4): 60-61
[11] 李祥. 利用啤酒废酵母生产 1,6-二磷酸果糖发酵工艺的研究[J]. 中国酿造, 2004, (6): 6-8
[12] 马文峰. 浓盐法提取啤酒废酵母中 RNA 的生产技术[J]. 酿酒, 1999, (1): 63
[13] 卞菁, 屠春燕, 欧阳平凯. 两种废弃酵母 RNA 提取工艺比较[J]. 南京化工大学学报, 1998, 20(1): 64-67
[14] 毛宁, 洪智勇, 郑清鹤. 提取核酸工艺的研究[J]. 现代科技, 1999, 11(3): 43-44
[15] 李珊, 吴振强. 盐法提取啤酒废酵母 RNA 研究[J]. 酿酒科技, 2005, (7): 76-78
[16] Hee Jeong Chae, Hyun Joo, Man-Jin In. Utilization of brewer’s yeast cells for the production of food-grade yeast extract[J]. Bioresource Technology, 2001, (76): 253-258
[17] Lee Jong soo, Hyun kwang wook, Jeong seung chan. Production of ribonucleotides by autolysis of pichia anmala mutant and some physiological activities[J]. Canadian Journal of Microbiology, 2004, 50(7): 489-492
[18] 邱雁临, 殷伟, 潘飞, 等. 吸附层析法从啤酒废酵母中提取谷胱苷肽[J]. 生物技术, 2005, 15(1): 49-52
[19] H. Liu, J. P. Liu, P. L. Cen. Co-production of methionine and glutathione from spent brewer’s yeast cells[J]. Process Biochmistry, 2004, (39): 1993-1997
[20] 布洛克. 微生物生物学[M]. 北京: 人民教育出版社, 1981: 168-170
[21] Schlenker G.D, Roland J. F. Tangential flow filtration for the recovery of beer and excess yeast[M]. Cerveza Malta, 1997: 23-28
[22] Gupta B. B, Howell J. A, Wu. D, etal. A helical baffle for cross-flow microfiltration [J]. Membanc Sci, 1995, (99): 31-42
[23] Moline M, Lcoll R. Cross-flow filtration of pectic substances during the enzymatic treatment of mandartn segment menbrannes[J]. Z Lebensm Unters Forsch, 1998, 20(6): 408-413
[24] 黄维菊, 陈文梅. 膜微滤强化技术国内进展[J]. 过滤与分离, 2003, 13(1): 1-5
[25] 田野. 利用啤酒废酵母生产优质酒基的研究[D]. 济南: 山东轻工业学院, 2006
[26] 白立勇. 利用啤酒废酵母生产优质酒基的研究[D]. 济南: 山东轻工业学院, 2007
[27] 王林, 胡平, 杨立苹. 浅谈高浓度醋的应用及市场前景[J]. 江苏调味副食品, 2004, 21(5): 5-8
[28] 刘军, 王亚利. 发酵型高酸度醋的应用及其酿造技术[J]. 江苏调味副食品, 2006, 23(1): 19-24
[29] 李涛. 粮食发酵制醋酸技术的研究进展[J]. 化工进展, 2001, (12): 26-29
[30] 赵良启, 李丽. 我国食醋生产技术的历史、现状与发展趋势(上)[J]. 中国调味品, 2005, 311(1): 3-6
[31] 解欣炜. 高产醋酸菌的筛选及小型 Frings 醋酸发酵实验[J]. 中国调味品, 2002, (7): 24-27
[32] 魏君兰, 鲁勇, 刘松. 应用酿酒高活性干酵母进行浓醪酒精发酵的试验[J]. 中国调味品, 2000, (3): 15-18
[33] 张忠明. 高产醋酸菌的筛选及其形态生化特征研究[J]. 甘肃农业大学学报, 2006, 41(1): 83-86
[34] 王克明. 生物反应器发酵海藻功能食醋的研究-多元混菌固定发酵海藻酒醪[J]. 中国调味品, 2006, (12): 28-32
[35] 吴定, 温吉华, 程绪铎, 等. 固定化酵母菌和醋酸杆菌发酵食醋工艺研究[J]. 中国酿造, 2005, (1): 20-22
[36] 张卫兵, 贠建民, 余群力. 采用固定化酵母酿造食醋的工艺研究[J]. 中国酿造, 2005, (11): 33-36
[37] 万辉. 醋酸-水体系的精馏过程研究[D]. 南京: 南京工业大学, 2003
[38] 杨春平. 从低浓度醋酸废水中萃取回收醋酸的研究[D]. 黑龙江: 哈尔滨工业大学, 1991
[39] 白鹏, 刘劲松, 杨志才. 回收废醋酸催化精馏过程的研究[J]. 四川大学学报(工程科学版), 2002, 34(5): 64-66
[40] Saha B, Chopade S P, Mahajani SM. Recovery of dilute acetic acid through esterification in a reactive distillation column [J]. Catalysis Today, 2000, 60(2): 147-157
[41] 黄峰, 张玉林. 从含酸废水中回收醋酸的方法[J]. 石油化工环境保护, 1998, (1): 6-9
[42] 秦炜, 王东, 戴猷元. 超声场对树脂吸附醋酸动力学影响的机理研究[J]. 清华大学学报(自然科学版), 2001, 41(4): 28-31
[43] 霍俊丽. 乙酸-水体系非均相共沸精馏过程的研究[D]. 天津: 河北工业大学, 2003
[44] 张培辉, 韦奇, 朱卫东, 等. 水-甲酸-乙酸混合物的共沸分馏[J]. 华东化工学院学报, 1993, 19(4): 427-431
[45] 李纪亮. 啤酒废酵母干燥工艺设计的研究[J]. 中国酿造, 2003, (1): 19-21
[46] 谭天恩, 麦本熙, 丁惠华. 化工原理[M]. 北京: 化学工业出版社, 1996: 189-280
[47] 基础化学工程编写组. 基础化学工程[M]. 上海: 上海科学技术出版社, 1978: 145-230
[48] 杨同舟. 食品化工原理[M]. 北京: 中国农业出版社, 2001: 149-186
[49] 方向红. 列管式换热器与板式换热器的比较[J]. 安徽化工, 2002, (4): 43-44
[50] 高德秋. 试论用半间歇式蒸馏流程生产符合GB394-81标准的一级酒精蒸馏技术[J]. 蔗糖工业, 1995, (1): 21-26
[51] 吴国峰, 李国金, 马勇强. 工业发酵分析[M]. 北京: 化学工业出版社, 2006: 97-99
[52] 大连轻工业学院等八院校合编. 食品分析[M]. 北京: 轻工业出版社, 1996: 75-233
[53] 周德庆. 微生物学教程[M]. 北京: 轻工业出版社, 2000: 212-213
[54] 黄仲华. 殷小平. 食醋生产问答[M]. 北京: 轻工业出版社, 2000: 212-213
[55] 沈国惠. 啤酒酵母自溶条件优化及其抽提物挥发性风味成分[J]. 食品与发酵工业, 1991, (3): 8-12
[56] 方尚玲, 马丽, 吴思方. 影响酵母自溶因素与条件的研究[J]. 粮食与饲料工 业, 2000, (3): 21-23
[57] 高玉荣. 啤酒废酵母自溶条件的研究[J]. 酿酒科技, 2002, 110(2): 74-76
[58] 万萍. 自溶促进剂乙醇自溶酵母最佳条件的研究[J]. 酿酒, 2000, 137(2): 62-65
[59] 吴思方, 方尚玲, 周林. 啤酒废酵母生产酵母味素的研究[J]. 中国酿造, 2000, 105(1): 11-13
[60] 张腊梅, 王树林. 醋酸菌液态发酵产酸的研究[J]. 青海大学学报, 1999, (5): 26-28
[61] 薛业敏, 郑桂富. 液态发酵法生产营养果醋的实验研究[J]. 中国调味品, 2002, (1): 17-19
[62] 薛业敏. 啤酒副产品在营养果醋生产中的应用[J]. 中国酿造, 2002, (6): 36-39
[63] 于水军, 王志勇. 稀醋酸母液中回收醋酸[J]. 焦作工学院学报, 1996, 15(6): 94-96
[64] 顾觉奋. 分离纯化工艺原理[M]. 北京: 中国医药科技出版社, 2002: 30-49
[65] Yuan-Hao Fu, Hasan Orbey, Stanley L Sandler, Prediction of Vapor-Liquid Equilibria of Associating Mixtures with UNIFAC models[J]. Ind. Eng. Chem. Res, 1996, (35): 4656-4666
[66] Kang, choon-Hyoung. Liquid equilibria or azeotropic ternary mixtures[J]. Hwahak Konghak, 1995, 33(2): 243-250
[67] Jung W, Chung I M, HeoH Y. Manipulating is of lavone levels in plants[J]. Plant Biotech, 2003, 5(3): 149-155
[68] 贾绍义, 李锡源. 二元非均相共沸物分离过程模拟计算[J]. 化学工程, 1994, 22(5): 13-19
[69] 刘光永. 化工开发实验技术[M]. 天津: 天津大学出版社, 1994: 232-235
[70] 廖永忠, 鲍坚斌. 共沸点的测定[J]. 石油化工, 1991, 20(3): 171-175
[71] 廖永忠, 韩世钧. 三元系共沸点的测定及预测[J]. 石油化工, 1991, 20(7): 473-476
[72] 隋振英, 邹东雷. 共沸精馏中共沸剂的选择[J]. 化学工程师, 1996, 54(3): 27