【作者】 刘秀华；

【导师】 唐晓珍； 樊兆森；

【作者基本信息】 山东农业大学 ， 生物与医药（专业学位）， 2022， 硕士

【摘要】 皱皮木瓜作为药食两用植物,营养物质丰富,具备多种生理功能。干制皱皮木瓜保存期长,可以避免成熟期集中引起的弊端,但食用加工技术较少,利用率低。乳酸菌发酵食品兼顾健康与口感,因此本研究利用干皱皮木瓜制备活菌型发酵饮料以提高皱皮木瓜利用率,为皱皮木瓜发酵饮料生产提供理论依据及工艺参数。主要研究内容与结果如下:(1)确定以植物乳杆菌:嗜酸乳杆菌:嗜热链球菌=1:1:1为发酵菌种,优化发酵工艺为发酵时间36 h、菌接种量3%(v/v)、糖浓度2%(w/v),在此条件下总酸为32.49 g/L,活菌数对数为11.79,p H值为4.55,感官评分为86.90分。(2)确定稳定工艺为卡拉胶0.04%(w/v)、魔芋胶0.08%(w/v)、果胶0.06%(w/v),此条件下发酵饮料沉淀率为1.02%。皱皮木瓜发酵饮料所含乳酸菌在人工胃液、人工肠液、氯化钠和胆盐的环境中皆有较好耐受性,活菌数在1×10~8CFU/m L以上。(3)皱皮木瓜发酵饮料总酸、总糖和总酚含量增加,提高了发酵饮料的功效。比较了皱皮木瓜汁和皱皮木瓜发酵饮料挥发性风味物质种类和含量,共鉴定出挥发性风味物质92种,主要为醇类、酮类、酯类、醛类和萜烯类;发酵饮料中丙酮、3-羟基-2-丁酮、乙醇、丙硫醇、异戊醇、正己醛、丁酸丙酯、乙酸薄荷酯、糠醛和β-蒎烯等物质比皱皮木瓜汁明显增多,为发酵饮料增添了奶油香、酒香、水果香和玫瑰香等独特气味,提高了抗氧化、抑菌杀菌和抗肿瘤等功效;4-异丙基甲苯、乙酸乙酯、苯乙烯、甲基庚烯酮、2-己酮、2-甲基丁醛、异戊醛、己酸乙酯和苯甲醛等物质明显减少,降低了一些刺激性气味。(4)以感官评分、活菌数、总酸和p H值为指标确定常温保质期为8天,冷藏(4℃)保质期为28天,在保质期内发酵饮料品质较高,活菌数高于6.92×10~8CFU/m L,满足国标要求1×10~6CFU/m L。发酵饮料感官品质和微生物指标均符合相关国家标准要求。(5)根据企业要求,设计了年产1000 t皱皮木瓜发酵饮料的生产工艺流程及操作要点、物料衡算和设备选型,并按照GB/T 31326和GB/T 31121制定皱皮木瓜发酵饮料技术标准。更多还原

【Abstract】 As a medicinal and edible plant,chaenomeles speciosa(Sweet)Nakai is rich in nutrients and has a variety of physiological functions.Dried chaenomeles speciosa(Sweet)Nakai has a long shelf life,which can avoid the disadvantages caused by the concentration of the mature period,but it has less edible processing technology and low utilization rate.Lactic acid bacteria fermented food takes into account both health and taste.Therefore,in this study,dry chaenomeles speciosa(Sweet)Nakai was used to prepare viable fermented beverages to improve the utilization rate of chaenomeles speciosa(Sweet)Nakai,and to provide theoretical basis and process parameters for the production of chaenomeles speciosa(Sweet)Nakai fermented beverages.The main research contents and results are as follows:(1)Determine Lactobacillus plantarum:Lactobacillus acidophilus:Streptococcus thermophilus=1:1:1 as the fermentation strain,and the optimized fermentation process was36 h fermentation time,3%(v/v)bacterial inoculum,and sugar.With a concentration of 2%(w/v),the total acid was 32.49 g/L,the logarithm of viable bacteria was 11.79,the p H value was 4.55,and the sensory score was 86.90.(2)The stable process was determined as carrageenan 0.04%(w/v),konjac gum 0.08%(w/v),pectin 0.06%(w/v),and the precipitation rate of fermented beverages under this condition was 1.02%.The lactic acid bacteria contained in the chaenomeles speciosa(Sweet)Nakai fermented beverage have good tolerance in the environment of artificial gastric juice,artificial intestinal juice,sodium chloride and bile salt,and the number of viable bacteria was more than 1×10~8CFU/m L.(3)The content of total acid,total sugar and total phenol in the fermented beverage of chaenomeles speciosa(Sweet)Nakai increased,which improved the efficacy of the fermented beverage.The types and contents of volatile flavor substances in chaenomeles speciosa(Sweet)Nakai juice and chaenomeles speciosa(Sweet)Nakai fermented beverages were compared,and 92 volatile flavor substances were identified,mainly alcohols,ketones,esters,aldehydes and terpenes;fermented beverages The substances such as acetone,3-hydroxy-2-butanone,ethanol,propanethiol,isoamyl alcohol,n-hexanal,propyl butyrate,menthyl acetate,furfural andβ-pinene were significantly higher than those of chaenomeles speciosa(Sweet)Nakai juice.It adds unique smells such as creamy,wine,fruit and rose fragrance to fermented beverages,and improves the effects of anti-oxidation,bacteriostasis and anti-tumor;4-isopropyltoluene,ethyl acetate,styrene,methyl Substances such as heptenone,2-hexanone,2-methylbutanal,isovaleraldehyde,ethyl hexanoate and benzaldehyde were significantly reduced,reducing some pungent odors.(4)The shelf life at room temperature was 8 days,and the shelf life at refrigerated(4℃)was 28 days based on sensory scores,viable bacteria count,total acid and p H value.The quality of fermented beverages during the shelf life was higher,and the viable bacteria count was higher than 6.92×10~8CFU/m L,meeting the national standard requirement of 1×10~6CFU/m L.The sensory quality and microbial indicators of fermented beverages meet the requirements of relevant national standards.(5)According to the requirements of the enterprise,the production process and operation points,material balance and equipment selection of the fermented beverage of chaenomeles speciosa(Sweet)Nakai with an annual output of 1000 t were designed,and the fermentation of chaenomeles speciosa(Sweet)Nakai was formulated in accordance with GB/T 31326 and GB/T 31121 Beverage technical standards.更多还原