臺灣博碩士論文加值系統

學號：N9236018
論文題目：本產牛乳應用於製作軟質乾酪之研究 　　　總頁數：98
學校名稱：國立屏東科技大學 系（所）別：食品科學系
畢業時間及摘要別：95學年度第1學期碩士學位論文摘要
研究生：梁鳳美 指導教授：劉展冏 博士
謝寶全 博士
論文摘要內容：
鮮乳是自然界中最均衡完美的食品，含有高量具有生物價值的蛋白質及各種人體必需之礦物質，為容易消化吸收之食品。台灣位於亞熱帶地區，因氣候及地理環境關係，乳牛平均泌乳量亦隨季節顯著變化，導致夏季鮮乳供不應求，而冬季鮮乳產量過剩，使得國內不斷發生剩餘乳問題，對國內酪農產業的發展造成巨大障礙。生乳的應用性廣泛，不同的民族有不同的使用方法，因而創造出非常多樣化之乳製品。本研究探討以本產牛乳進行技術較簡易可行之軟質乾酪加工可行性，作為消耗剩餘牛乳的途徑。
研究中使用三種不同商業菌粉，分別為A菌粉、B菌粉、C菌粉。將生乳以71 - 75℃、加熱15秒殺菌，冷卻至45℃後加入乳酸菌原，經發酵作用產生乳酸而造成凝乳反應，靜置6~8小時，截切使乳清排除，經過濾壓榨後定型、抹乾鹽過程中添加不同食鹽濃度(0％、0.5％、1％)製成軟質乾酪，以探討含鹽量對製得軟質乾酪之基礎成份、物化特性暨感官品評等各項性質之影響。
研究結果顯示，季節更替對生牛乳組成分有影響。各月份平均之乳脂率、蛋白質、比重及非脂固形物含量上，以冬季乳最高，而體細胞數及細菌數含量則以冬季乳最低。軟質乾酪成品之一般成分分析發現，由商業菌粉C發酵所製得之軟質乾酪，具有最高的粗脂肪與粗蛋白含量，並且具有最低的水分含量。在胺基酸組成分析方面，商業菌粉C所製得之軟質乾酪具有較高成份之多種胺基酸。由軟質乾酪有機酸(包含乳酸，檸檬酸，醋酸及丁酸)含量測定結果顯示，儲存前新鮮軟質乾酪之有機酸含量以利用A組菌株發酵者含量最高，貯存後，各組配方中除乳酸增加外，其他有機酸均大幅度地降低。軟質乾酪貯存期間一般物化特性之變化上，以C組發酵者之水分含量顯著低於利用A菌與B菌發酵者，但是水活性並無太大差異。軟質乾酪中以A組pH值較其他兩組低，A組之可滴定酸度較其他兩組高，可印證A組之較高有機酸含量結果。質地剖面分析結果顯示，軟質乾酪之硬度、彈性、黏著性、膠粘性及咀嚼性均以C組為最高。在感官品評方面，整體而言，3種商業菌粉或添加不同鹽量，並無顯現對軟質乾酪成品外觀色澤具決定性之影響，但以B與C組整體接受性最高；而經過4℃，16天的貯存，對軟質乾酪之品質亦無顯著影響。最後對於貯存期間乳酸菌數之變化，C組乳酸菌含量明顯高於A與B組。
本研究證實使用本產冬季剩餘乳添加商業菌粉，製作軟質乾酪之加工技術可行性，可供本省酪農參考，應用冬季剩餘鮮乳，以產製本地軟質乾酪，取代進口產品，作為食品或烘焙加工業者之原料。

關鍵字:軟質乾酪、乳酸菌、感官品評、質地剖面分析

Student ID: N9236018
Title of thesis: Study of Soft Cheese Manufacturing by Utilizing Domestic Milk
Total page: 98
Name of Institute: Graduate Institute of Food Science, National Pingtung University of Science & Technology
Graduate date: January, 2007 Degree Conferred: Master
Name of student: Feng-Mei Liang Adviser: Chan-Chiung Liu
Pao-Chuan Hsien

The contents of the abstract in this thesis:
Milk is one of the natural resources which contains well-balanced nutrients, such as variety of proteins and necessary minerals for human body, also is easily digestible. Taiwan is located in subtropical zone, milking cows tend to produce more milk during winter than other seasons. Consumers reduce the consumption of cold milk during winter, which subsequently leads to the over production of milk year after year. The disparity between production and consumption of milk has become one of the primary obstacles for the dairy industries in Taiwan. The project aimed at exploring the possibility of soft cheese manufacturing by utilizing domestic milk. The subject was chosen because of relative easiness.
Three different commercial lactic bacterial powders were applied in this study, namely A, B, and C, respectively. The raw milk was first sterilized by thermal process at 71 – 75℃ for 15 seconds, lactic acid bacteria was inoculated after the milk was cooled to 45℃. Lactic acid was generated through fermentation, and then curding took place. Settling for 6 -8 hours, and then cutting of whey was followed by filtration and pressing, soft cheese was finally obtained. Different salt contents (0, 0.5% and 1.0%, respectively) were tested in the manufacturing processes to investigate the effects of salt on the fundamental compositions, physicochemical characteristics, and sensory attributes.
The results showed that season change truly affect the composition of raw milk produced. The monthly average milk fat percentage, protein content, specific gravity, non-fat-solid all showed the highest amounts, whereas the somatic and bacterial counts were lowest for the winter. Proximate composition analysis revealed that the soft cheese made by commercial powder C had the highest crude fat and protein, and the lowest moisture content. Products by bacterial powder C also had the most abundant amino acids. The organic acid compositions (including lactic acid, citric acid, acetic acid, and butyric acid) for products via powder A were highest, and all the organic acids except lactic acid reduced significantly after storage at 4℃ for 16 days. As to the changes of general physicochemical characteristics, Group C had the lower moisture contents than Groups A and B, but the water activities were similar. Textural profile analysis by Instron demonstrated that Group C had the highest hardness, springiness, adhesiveness, gumminess, and chewiness. Sensory evaluation by 15 panelists concluded that the appearance and color of products would not be decisively affected by different bacterial powders employed, neither the salt added. Groups B and C had higher overall acceptability. Storage at 4℃ for 16 days did not yield significant outcomes for the manufactured soft cheese. Last but not least, Group C had the highest amount of lactic acid bacteria.
This research proved the feasibility of soft cheese production by domestic milk through commercial bacterial powders. Hopefully this could benefit the domestic dairy industries for utilizing the over produced milk during winter season. The domestic cheese has the potential for food and baking industries in substituting foreign imports.

Keywords: soft cheese, lactic acid bacteria, sensory evaluation, texture profile analysis

中文摘要……………………………………………………………………Ⅰ
英文摘要……………………………………………………………………Ⅲ
誌謝…………………………………………………………………………Ⅴ
目錄…………………………………………………………………………Ⅵ
圖表目錄……………………………………………………….……………Ⅹ
第一章、 前言………………………………………………………………1
第二章、 文獻回顧…………………………………………………………...2
2.1 台灣牛乳產業………………………………………………………..2
2.2 台灣乳品供給、需求與鮮乳消費趨勢................................................6
2.2.1乳品供給…………………..…….………………………………6
2.2.2乳品需求與鮮乳消費趨勢…………………………...…………6
2.3 生乳收購標準、乳品銷售型態……………………………………..10
2.3.1生乳收購標準……………………….…………………………10
2.3.2乳品銷售型態………………………………………...………..11
2.4 乾酪之起源…………………………………………………………13 2.5 乾酪之分類………………………………………………………....14
2.5.1超硬質乾酪……………….…………………………………...14
2.5.2硬質乾酪.……………………………………………………...14
2.5.3半硬質乾酪.…………………………………………………...14
2.5.4軟質乾酪....……………………………………………………14
2.5.5特殊乾酪.……………………………………………………...14
2.6 乾酪之營養價值..…………………………………………………..17
2.6.1乳脂肪………………………………………………………….17
2.6.2乳蛋白質……………………………………………………….17
2.6.3維生素………………………………………………………….19
2.6.4礦物質………………………………………………………….20
2.6.5乳糖及乳酸…………………………………………………….21
2.7乾酪製造之流程……………………………………………….21
2.7.1原料乳之選擇…………………………………………………23
2.7.2殺菌……………………………………………………………23
2.7.3乾酪菌原………………………………………………………23
2.7.4凝乳酶…………………………………………………………24
2.7.5 凝乳之生成.. ………………………..………………………25
2.7.6 截切……………………………………………….…………25
2.7.7 乳清之排除…………………………………….……………25
2.7.8 定型與壓榨……………………………………….…………25
2.7.9 加鹽…………………………………………………………26
2.7.10 乾酪之熟成…………………………………...……..……26
2.8 乳酸菌之特性與應用………………………………………………26
2.9 乾酪風味物質的生成………………………………………………31
第三章、 材料與方法………………………………………………………35
3.1實驗架構……………………………………………………………..35

3.2實驗原料……………………………………………………………..37

3.3分析方法……………………………………………………………..37
3.3.1生乳一般成份分析…………………………………………….37
1.脂肪、蛋白質、固形物、非脂固形物測定…………………….37
2.比重測定………………………………………………………38
3.細菌數測定………………………………………………….…38
4.體細胞數測定………………………………………………….39
5.抗生素殘留快速檢驗方法……………...……………………..40
3.3.2乾酪成份分析………….………………………………………41
1.粗脂肪測定……………..……………………………...………41
2.粗蛋白質測定…………………………….……………………44
3.灰分之測定………………………………………………….…45
4.有機酸成分分析……………………………………………….45
5.胺基酸組成分分析………………………………………….....45
3.3.3乾酪貯存試驗………………………………………………….48
1.水分測定….……………………………………………………48
2.水活性測定…………………………………………………….49
3.pH值測定..…………………………………………………… 49
4.酸度測定……………………………………………………….49
5.質地剖面分析………………………………………………….50
6.色澤測定…………….…………………………………………52
7.乳酸菌測定…………………………………………………….52
8.感官品評…………………………………………………….…52
9.統計分析……………………………………………………….52
第四章、 結果與討論………………………………………………………53
4.1生牛乳成份分析……………………………………………….……53
4.1.1季節不同對生牛乳組成分之變化………………………...…..53
4.1.2季節不同對生牛乳體細胞數之變化………………………….53
4.1.3季節不同對生牛乳微生物之變化…………………………….53
4.2 新鮮軟質乾酪成份分析……………………………………………54
4.2.1 一般組成份分析………………………………………...……54
4.2.2 胺基酸組成分析………………………………………..…….54
4.3 軟質乾酪有機酸含量………………………………..……………..54
4.4 軟質乾酪貯存期間一般物化特性之變化………………………....55
4.4.1 水分含量……………………………………………………...55
4.4.2 水活性……………………………………………………...…55
4.4.3 pH值………………………………………………………....55
4.4.4 可滴定酸度………………………………………………..….56
4.5 軟質乾酪貯存期間質地剖面特性之變化……………………..…..56
4.5.1 硬度………………………………………………………...…56
4.5.2 彈性………………………………………………………...…56
4.5.3 黏著性………………………………………………………...57
4.5.4 內聚性………………………………………………………...57
4.5.5 膠粘性………………………………………………………...57
4.5.6 咀嚼性……………………………………………………...…57
4.6 軟質乾酪貯存期間外觀顏色之變化………………………………58
4.7 軟質乾酪貯存期間乳酸菌數之變化………………………...…….58
4.8 軟質乾酪感官品評…………………………………………………58
4.8.1 新鮮軟質乾酪儲存前感官品評……………………………...58
4.8.2 軟質乾酪儲存後感官品評………………………………..….59
第五章、 結論…………………………………………………………….…89
參考文獻…………………………………………………………………90
附錄……………………………………………………………………….....97
作者簡介………………………………………………………………98


























圖表目錄

圖1、台灣牛乳的生產量消長……………..……………………………… 3
圖2、台灣生產牛乳之農場數目消長…………………..………………… 4
圖3、台灣乳牛數目之消長………............…………………………………5
圖 4、台灣鮮乳產量與乳品進口量消長(1992-1999)...…………………….9
圖 5、各種依據熟成媒介以及其硬度而分類之乾酪..……………………16
圖6、酪蛋白微囊胞構造之模型………..…………………………………18
圖7、製作乾酪之主要步驟…………………………….………………….22
圖8、胺基酸轉化為風味物質之生合成途徑…...………………………. 34
圖 9、實驗架構流程…..……………………………………… …...............35
圖10、乾酪製作流程……….……………………………………….............36
圖11、索氏萃取裝置……...…...…………………………………………....43
圖12、質地剖面分析圖..........………………………………………………51
圖13、各月份平均之乳脂率…………………..…….…..………………….68
圖14、各月份平均之蛋白質…………..……………………………………69圖15、各月份平均之非脂固形物……..……………………………………70圖16、各月份平均之比重……………..……………………………………71
圖17、各月份平均之體細胞數……..…………………………..…..………72
圖18、各月份平均之細菌數………………..………………………………73
圖19、軟質乾酪製作完成圖.........………………………………………….74圖20、軟質乾酪貯存期間水分含量之變化…..……………………………75
圖21、軟質乾酪貯存期間水活性之變化…..………………………………76
圖22、軟質乾酪貯存期間pH值之變化………..…………………………..77
圖23、軟質乾酪貯存期間酸度之變化………………………..…………… 78
圖24、軟質乾酪貯存期間硬度之變化………………………..………..….. 79
圖25、軟質乾酪貯存期間彈性之變化……………………..……………… 80
圖26、軟質乾酪貯存期間黏著性之變化…………………..………….… ...81
圖27、軟質乾酪貯存期間內聚性之變化.………………………………… 82
圖28、軟質乾酪貯存期間膠黏性之變化…..……………………………….83
圖29、軟質乾酪貯存期間咀嚼性之變化…..……………………………….84
圖30、不添加食鹽軟質乾酪貯存期間外觀顏色之變化…….……………..85
圖31、添加0.5％食鹽軟質乾酪貯存期間外觀顏色之變化…....…………86
圖32、添加1％食鹽軟質乾酪貯存期間外觀顏色之變化………..………..87
圖33、軟質乾酪貯存期間乳酸菌數之變化………….……….……………88
表1、歷年台灣乳品進出口數量………………………….…………………7
表2、歷年來牛乳製品需求量及平均每人鮮乳消費量…..……………...…8
表3、各國的乾酪消耗量….….….…………………….…………………. 12
表4、數種乾酪之維生素含量….………….….………………………........20
表5、數種乾酪之礦物質含量…….…………………………………..……21
表6、乳酸菌之分類…………..…………………………………………… 30
表7、數種因乾酪熟成期間胺基酸分解而形成的產物…..…… …………32
表8、乾酪熟成期間數種主要揮發性物質…………… ………………….33
表9、新鮮軟質乾酪一般成份分析…………………..…………………….60
表10、不添加食鹽軟質乾酪之胺基酸組成………….……………………..61
表11、添加0.5％食鹽軟質乾酪之胺基酸組成…....……………………….62
表12、添加1％食鹽軟質乾酪之胺基酸組成…...….………………………63
表13、軟質乾酪儲存前有機酸含量.….……………………………………64
表14、軟質乾酪儲存後有機酸含量.……………………………………….65
表15、軟質乾酪貯藏前之感官品評…………...……………………………66
表16、軟質乾酪貯藏後之感官品評…..…………………………………….67

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