干酪和酸乳制造原理DSM.ppt

1、1,Cheese making 牛奶脂肪实质是一种甘油三酯混合体（98%脂肪）；,several fatty acids (up to C19); seasonal etc variations 一些脂肪酸（大于19个碳）；季节性等的变化, Fat globules phospholipid / protein membrane various Size,脂肪球磷脂/蛋白质膜各种大小,DSM Food Specialties,10,Milk components Lactose 牛奶成分乳糖, Lactose is the sole milk carbohydrate 乳糖是牛奶中唯一的一种糖

2、,-galactoside 半乳糖苷, Hydrolysed by -galactosidases (lactases) 半乳糖苷酶水解（乳糖酶）,DSM Food Specialties,11,Milk Components Endogenous enzymes内源酶, Plasmin (alkaline, thermostable, seasonal variations) 纤溶酶（碱性，耐热性，季节性变化）, Lipoprotein Lipase (LPL; inactivated by pasteurisation) 脂蛋白脂酶（LPL；巴氏杀菌法灭活）, Phosphatases (

3、acid 一般42-43度 also at 37-39C / down to 30C 也有37-39度/低于30度,Great impact on texture of final product对终产 品质构影响较大,Impact on (post) acidification影响酸度,Starter inoc,Stirring surviving microflora will affect flavour不能杀死所有生物体；幸存 的微生物会影响风味 Milk preparation,Standardisation Protein/fat ratio standardisation蛋白/脂

4、肪比例标准化 Concentration (ultrafiltration, microfiltration, .)浓缩 Bactofugation离心除菌 low temperature heat treatment低温热处理 High temperature heat treatment高温热处理 Addition of milk solids乳固体 cold maturation with starters, .发酵剂冷成熟 DSM Food Specialties,Excessive heating causes -lactoglobulin to bind to -casein ac

5、ross the chymosin-sensitive bond 105-106 PHE-MET GMP -lactoglobulin,36,Cheese manufacturing Process干酪加工工艺,Raw milk,Pasteurisation,Vat filling,Coagulation,Coagulant,Milk preparation Standardisation,Starters CaCl2, colours,.,Cutting / Stirring, Ripening,Moulds Salting Pressing,Curd,Whey separation Whe

6、y,DSM Food Specialties,37,Cheese manufacturing Process Vat filling Coagulant Starters,Excessive foaming can:过多的泡沫可以： slow acid production by starter发酵剂产生低酸 cause uneven coagulant distribution 导致混凝剂分布不均 cause uneven colour distribution 导致颜色不均Colours, e.g. anatto, CaCl2, colours,. Coagulants混凝剂 Animal

7、 rennet动物凝乳 Chymosin凝乳酶 Microbial proteases微生物蛋白酶 Plant proteases植物蛋白酶,Starters发酵剂 - Acidify the milk酸化牛奶 - Contribute to sensory properties of cheese by the action of their enzymes 凝乳酶最高温度42度 activity begins to drop off above this temperature高于42度活性下降 Enzyme activity increases approximately 3% per

8、degree between 20C and 38C 20-38度之间酶活性每度约降低3% Cutting increases the surface area and enhances syneresis Acidity immediately drops (lower buffer capacity of whey vs. milk) Curd particles immediately begin to expel whey and shrink 搅拌可增加表面积和增强收缩能力， 酸度下降（相对牛奶，乳清缓冲能力低）， 排出乳清，收缩，凝乳颗粒形成 DSM Food Specialtie

9、s,Coagulation Cutting / Stirring,40,Cheese manufacturing Process,Raw milk,Pasteurisation,Vat filling,Coagulation,Coagulant,Milk preparation Standardisation,Starters CaCl2, colours,.,Cutting / Stirring, Ripening,Moulds Salting Pressing,Curd,Whey separation Whey,DSM Food Specialties,41,Cheese manufact

10、uring Process 干酪加工工艺 Freshly cut curd is very fragile and shatters easily if stirred vigorously Cutting knives must be sharp to avoid fat and protein losses Curd still has a relatively open structure and readily expels whey Healing allows the curd to shrink and firm up, to better withstand agitation

11、 during cook新形成的凝乳如果大力搅拌很容易破碎，切割刀 必须锋利以防脂肪和蛋白损失；凝乳结构相对开放，容易排出乳清； 凝乳收缩坚硬，更能承受搅拌,Equilibrium whey/curd mixture乳清/凝乳混合平衡,Cutting / Stirring,Lactose乳糖 Whey separation,pH,Acid酸,Ca / P钙/磷 Whey DSM Food Specialties,42,Cheese manufacturing Process干酪加工工艺 Acid Heat Rennet Agitation Time,Curd particle after sh

12、ort heal period,Syneresis causes the curd particle to shrink and condense,Cutting / Stirring Higher temperature enhances syneresis高温促进脱水收缩,Temperature increase affects starter growth温度升高影响发酵剂生长 Stirring promotes syneresis搅拌促进脱水收缩 Curd particles continue to shrink and firm up凝乳颗粒继续收缩坚硬 Longer stir-ou

13、t time can significantly reduce moisture levels in the cheese长时间搅拌可减少干酪中的水分 DSM Food Specialties,Whey separation Whey,43,Cheese manufacturing Process Washing (optional, e.g. Gouda types)清洗（可选，例荷兰产高德干酪） Removes lactose and lactic acid from curd从凝乳中去除乳糖和乳酸 Washing results in higher final cheese pH (li

14、mits lactose)清洗可获得较高pH的干酪（限制乳糖） Syneresis directly affected by water temperature (low-slows, high-enhances)水温直接影响脱 水收缩作用（低-慢，高-强） Long wash times remove more lactose and lactic acid from the curd清洗时间长，可排除更多的 乳糖和乳酸 Cool wash water reduces curd temperature and allows temperature-sensitive strains to r

15、eturn from stationary to log phase冷水清洗减少愈合温度且允许温度敏感株从稳定期到对数生长期 Cutting / Stirring Equilibrium whey/curd mixture乳清/凝乳混合平衡,Lactose乳糖,Whey separation,pH,Acid酸,DSM Food Specialties,Ca / P钙/磷,Whey,44,Cheese manufacturing Process,Raw milk,Pasteurisation,Vat filling,Coagulation,Coagulant,Milk preparation S

16、tandardisation,Starters CaCl2, colours,.,Cutting / Stirring, Ripening,Moulds Salting Pressing,Curd,Whey separation Whey,DSM Food Specialties,45,Cheese manufacturing Process Pressing压榨 Gives cheese its final shape赋予干酪最后的形状 Eliminates openings between curd particles清除凝乳颗粒间的缝隙 Promotes curd fusion by b

17、ringing curd促进融合，使颗粒紧密接触 particles into close contact Presses more free whey from the curd (small quantity)压出更多的乳清（小数量） All lactose remaining in the curd should be fermented by 24 hours凝乳中的所有乳糖发酵24h,DSM Food Specialties,Moulds Pressing,Curd,46,Cheese manufacturing Process Cheddaring堆酿 A special proc

18、ess, specific to Cheddar cheese types 这是切达干酪的特殊工艺 Curd is let to set few minutes凝乳放置几分钟 “Loaves” of curd are cut, turned and stack再被分割成相同大 小的几块，翻转堆叠 After completing the turning, the curd is milled,然后切成小块， then dry salted and placed into moulds干腌，放入模具中,DSM Food Specialties,Moulds Pressing,Curd,47,Ch

19、eese manufacturing Process,Raw milk,Pasteurisation,Vat filling,Coagulation,Coagulant,Milk preparation Standardisation,Starters CaCl2, colours,.,Cutting / Stirring, Ripening,Moulds Salting Pressing,Curd,Whey separation Whey,DSM Food Specialties,48,Cheese manufacturing Process,Salt enhances flavour盐增强

20、风味 Extracts more whey from curd凝乳中提取更多乳清 Salt absorption is rapid, but salt盐吸收迅速，但 equilibrium in curd very slow在凝乳中均匀较慢 (several days or weeks)(需几天或几星期) Salt slows or stops growth of salt sensitive starter strains (when direct,Photo: F. Kosikowski in Scientific American,Dry salting,salting)盐减缓或阻止盐敏

21、感菌株生长（直接盐腌时） Salt helps avoiding growth of Butyric Acid Bacteria (late blowing)盐可抑制丁酸菌生长 （后期产气） Moulds Brine bath,Salting DSM Food Specialties,Pressing,49,Cheese manufacturing Process,Raw milk,Pasteurisation,Vat filling,Coagulation,Coagulant,Milk preparation Standardisation,Starters CaCl2, colours,.,Cutting / Stirring, Ripening,Moulds Salting Pressing,Curd,Whey separation Whey,DSM Food Specialties,50,Cheese manufacturing Process Ripening or Maturation or Ageing成熟 A complex biochemical process involving 该过程是一个包含大量 a large number of