Yogurt-the ever-popular fermented milk |
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優酪乳-永遠受歡迎的發酵牛奶 |
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According to the Codex Alimentarius (5), yogurt is milk (usually cow's milk) that has been fermented by Streptococcus thermophilus and Lactobacillus bulgaricus under defined conditions of time and temperature. Each species of bacteria stimulates the growth of the other, and the products of their combined metabolism produce the characteristic creamy texture and mild acid flavor. Fermentation is stopped by cooling, and the final product, which contains 100-1000 million live bacteria per ml, is refrigerated until use. As a fresh dairy product, it has a limited shelf-life. |
根據Alimentarius抄本,優酪乳是牛奶(通常是母牛,奶牛
的乳汁)藉由菌種Streptococcus thermophilus及
Lactobacillus bulgaricus在限定的時間及溫度下發酵而成。
每一種細菌都激發他種細菌的生長,而它們結合的新陳代
謝產物產生乳脂狀特徵及不濃烈的酸味。發酵作用一經冷
卻即終止,而其最終的產物-優酪乳,直至使用前均需被
冷藏,每一亳升中包含十億至百億隻活菌。一如新鮮的乳
牛產品,它的生命是有期限的。 |
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1.Milk digestibility |
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1.牛奶之消化性 |
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Given all the research to date on FM, the fact that lactose is better digested from yogurt than from milk by lactasedeficient individuals is the most well-established health benefit (6). Yogurt ingestion leads both to less hydrogen production in the breath hydrogen test (lactose maldigestion) (Figure 1) and to reduced symptoms (lactose intolerance) (Marteau, 1990; Lerebours, 1989; Kolars, 1984). This effect is related to the living bacteria, the enzymatic content (e.g., B-galactosidase), and the texture of yogurt. |
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屬於發酵乳的所有研究提供此事實:優酪乳中的乳糖藉由
乳糖缺乏的個體較牛奶中乳糖更易吸收且最具健康效益。
優酪乳攝取導致氫呼吸測試中較少之氫產物及降低乳糖不
適症的症狀。此效果與活菌,含量(B-galactosidase)及
發酵乳的組織結構(酵素的特徵)有關。 |
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2.Recovery from diarrhea |
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2.由痢疾復原 |
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Yogurt reduces the duration of certain types of diarrhea, especially in children (Niv, 1963; Boudraa,1990). The World Health Organization (WHO,1995) recommends that during treatment of diarrhea, yogurt should replace milk when available since it is better tolerated than milk and can help prevent malnutrition or reestablish nutritional adequacy. |
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屬於發酵乳的所有研究提供此事實:優酪乳中的乳糖藉由
乳糖缺乏的個體較牛奶中乳糖更易吸收且最具健康效益。
優酪乳攝取導致氫呼吸測試中較少之氫產物及降低乳糖不
適症的症狀。此效果與活菌,含量(B-galactosidase)及
發酵乳的組織結構(酵素的特徵)有關。 |
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3.Immunomodulating effects |
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3.調整免疫效能 |
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Yogurt has been shown to enhance various parameters of the immune system in in vitro models (13) and in mice (14-16). In humans, one study found an improvement in clinical symptoms of nasal allergy, but no changes in any parameters tested (17). A recent report with atopic subjects found no significant modification of immune system parameters, showing that there was no aggravation of the immune system caused by yogurt (18). Very high concentrations of yogurt bacteria have led to increases in IFNy, B lymphocytes, and natural killer cells (19), and yogurt consumption increased 2', 5'-a synthetase activity (a reflection of production of IFNy) (20). |
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在Vitro模式及鼠類上,優酪乳已顯示出可提高各種免疫系
統的變數(參數)。針對人類而言,一研究亦已發現臨床
上過敏性鼻炎之症狀獲得改變,但在任何參數測試值並無
改變。最近針對遺傳性過敏症的主題報告中發現無免疫系
統參數上之重要變異,顯示出免疫系統不會因優酪乳導致
惡化。極高濃度的優酪乳活菌導致增強IFNy,B淋巴細胞
及殺死壞細胞之自然細胞,且優酪乳之消耗提高2',5'-a
synthetase活動(一種IFNY的反射產物)。 |
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4.Reduction of risk of cancer |
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4.降低癌症危機 |
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A recent epidemiological study from France showed that people consuming yogurt had less risk of developing large colorectal adenomas (21). In addition, the consumption of yogurt in elderly subjects with atrophic gastritis led to a decrease in the procarcinogenic fecal enzymes nitroreductase and azoredeuctase (22). Research in this field is intriguing, but preliminary. |
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最近由法國發表的傳染病邏輯學研究顯示喝優酪乳者較少
有發展大colorectal (結腸)腺腫瘤的危險。
除此之外,過了中年又有遺傳性過敏症的胃炎者喝優酪乳
可使procarcinogenic排泄物的nitroreductase及azoreductase減少
。在這方面領域的研究很引人感興趣,但目前卻只是初步
研究。 |
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5.Blood cholesterol levels |
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5.血膽固醇水平﹝程度﹞ |
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Mann and Spoerry (23) reported over 20 years ago that Maasai warriors consumed several liters of FM per day and yet had low serum cholesterol levels. This observation sparked a series of conflicting studies on the possible hypocholesterolemia properties of yogurt and other FM. Results have been inconsistent (24). What is clear is that regular consumption of yogurt does not increase plasma cholesterol concentration (24,25); yogurt can be part of the daily intake of individuals who are concerned about heart disease. |
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20多年前,Mann及Spoerry兩人之研究報告指出:Maasai的
戰士們每日飲用地好幾公升優酪乳,即擁有低血清膽固醇
的健康水平。這項觀察引起了優酪乳對於低膽固醇屬性可
能性的相矛盾研究。結果仍是不一致且互相矛盾。
但唯一可肯定而明確的是:規律性地飲用優酪乳不會增加
血漿膽固醇的濃度;優酪乳可作為疑有心臟方面疾病患者
每日吸收的營養之一部分。 |
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Kefir, another traditional fermented milk |
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Kefir,另一種傳統的發酵乳品 |
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Kefir is a stirred beverage made from milk fermented with a complex mixture of bacteria (including various species of lactobacilli, lactococci, leuconostocs, and aceterobacteria) and yeasts (both lactose-fermenting and non-lactose-fermenting). The small amount of CO2, alcohol, and aromatic compounds produced by the cultures give it its characteristic fizzy, acid taste (26). Kefir fabrication differs from that of yogurt in that kefir grains (small clusters of microorganisms held together in a polysaccharide matrix) or mother cultures from grains (27) are added to milk and cause its fermentation. Kefir is actually a family of products, in that the grains and technology used can very significantly and thus result in products with different compositions. |
Kefir(中溫菌的一種)是一種由牛奶和一些複雜細菌混合
發酵而成的攪拌式飲料(包含很多種類的lactobacilli, lactococci, leuconostocs,及aceterobacteria)及酵母菌(有具乳糖
發酵及無乳糖發酵兩種)。少量的二氧化碳,酒精及香料
(芬芳的)化合物由微生物等的培養菌賦予它泡沫騰湧般
及酸味的特性。Kefir製造上和優酪乳不同在於Kefir麥芽粕
(一小群聚集在一個多醣類母體組織的微生物)或由麥芽
粕添加至牛奶中而導致發酵作用的母培養菌製作而成。
Kefir事實上是一整族的產物,因麥芽粕及科技上利用後能
明顯地改善而因此導致有不同成分的產物產生。 |
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Many health benefits have been traditionally reported. Kefir has been used for the treatment of atherosclerosis, allergic disease, and gastrointestinal disorders, among other diseases (28). Until recently, most research has been limited to studies lacking modern statistical practices or to reports written up in Slavic languages, rendering them inaccessible to most western scientists. |
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很多Kefir在健康上的益處以往已被報導過。Kefir現在己廣
泛使用於動脈硬化症,過敏性疾病及胃與腸的失調疾病治
療上。直至現今,大部份研究均被局限於缺乏現代的統計
實證或因研究報告以斯拉夫語言寫成而其譯文,翻譯方式
又難獲得於大部份西方科學家的認同及了解。 |
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Recent studies have investigated antibacterial (29), immunological (30), antitumoral (31), and hypocholesterolemia (32) effects of kefir consumption on animals. Results suggest potential benefits. Fresh, but not heat-treated grains in kefir enhanced intestinal lactose digestion in minipigs (33). While awaiting more research, it is important to remember that kefir, like yogurt, has been and continues to be a part of the regular diet in central and eastern Europe for centuries. |
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最近的研究已在動物攝取Kefir的效果上分析研究出抗菌劑
,免疫邏輯學的,抗腫瘤的,及低膽固醇血症的效能。其
研究結果建議潛在性的益處。新鮮但存在於Kefir中不經熱
處理的麥芽粕在迷你豬實驗證實可增強腸內乳糖的消化。
在等待更多研究支持的同時,重要的是要記住:Kefir一如
優酪乳(yogurt)一樣已經是中歐及東歐幾世紀以來且將
持續下去的慣有飲食的一部份。 |
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Bifidobacterium: a natural inhabitant of the intestinesBifidobaceria were first described in 1900 by Tissier (34). Since that time, their classification has evolved continually, and currently includes around thirty sopecies (35,36). In general, they are strictly anaerobic, Gram positive rods which often have special nutritional needs and grow slowly in milk. Very few strains are adapted well enough to milk that they both grow in sufficient numbers and survive well throughout the shelf-life of the FM. Although bifidbacteria produce both lactic acid and acetic acid as major end-products of metabolism (heterofermentative), many microbiologists consider them to be lactic acid bacteria, albeit a special case. |
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Bifidobacterium(發酵菌種):首在1900年由Tissier描述乃為
一種腸內天然的動物Bifidobacteria。從那個時起,他們的分
類法一再進展,直至現今包含了約三十種種類。一般而言
,革蘭低陽性菌具沒有空氣而能生活的厭氧性特徵,其菌
枝條通常在牛奶中有特殊的營養上的需求且能在牛奶中緩
慢地生長。極少動植物的品系可在牛奶中適應的相當好,
但卻可透過優酪乳有限的生命生長出足夠的數量及存活良
好。雖然Bifidobacteria同時產生乳酸及醋酸-如新陳代謝下
的主要終端產物,但許多微生物學者認為雖然這屬特殊個
案,但仍認為Bifidobacteria屬醋酸類細菌。 |
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Tissier's hypothesis almost 100 years ago that bifidbacteria might have health benefits (37) was hased on the following observations. Bifidbacteria are normal inhabitants of the human intestinal tract throughout the life cycle, beginning just days after birth. Further, they are often the predominant microorganism in the gut of breast-fed infants. It has since been shown that breast-fed babies are less at risk for diarrhea disease than formula-fed infants (38). |
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大約百年前Tissier的假說指出Bifidobacteria可根據以下觀察
發現證實具健康益處。Bifidobacteria是自出生後約一天即存
在人體腸道內透過生命循環的活菌。
因此,他們是在吃母奶的嬰兒腸內的卓越微生物。早己被
證實顯現的是餵食母奶的嬰幼兒較餵食其他食品的嬰兒較
少有腹瀉(痢疾)的危機。 |
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In addition to the above inherent characteristics of bifidobacteria, some strains of the micro-organism survive intestinal transit in sufficient numbers to exert a metabolic effect in the gut (39,40). |
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除了以上Bifidobacteria固有的特徵外,某些此種微生物的品
系若有足夠的數量可促進了存於腸內的有效地蠕動及發揮
腸內新陳代謝的效能。 |
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1.Effects on the intestinal microflora |
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1.腸內微小植物的效能 |
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Ingestion of milk fermented with bifidobacteria leads to an increase in fecal bifidobacteria levels, both in infants (43) and in adults (44). Elevated levels return to normal after cessation of consumption (Figure 2)(39). Ingestion of FM with bifidobacteria has also led to a decrease in B-glucuronidase activity, but not in other enzymes associated with colon (44). |
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同時針對嬰兒及成人而言,攝取Bifidobacteria發酵後的牛奶
導致排泄物的Bifidobacteria程度增大。有活力的程度在停止
消耗後回復正常標準。攝取含Bifidobacteria的優酪乳亦導致
B-glucuronidase活動的降低,但不包含與結腸聯想在一起的
其他酵素。 |
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2.Effect on mild constipation |
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2.針對輕微便秘之效能 |
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Slow intestinal transit can be partially corrected in women by the regular consumption of a milk fermented with yogurt cultures and bifidobacteria (41). This effect was not observed with yogurt as a control, thus demonstrating the specificity of bifidobacteria for the increased colonic motility (42). |
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藉由規律性地飲用以酵母培養菌及Bifidobacteria發酵過的牛
乳,尤其顯著於女性修正腸的緩慢蠕動。這種效能並未將
優酪乳視為〔由實驗確定〕的對照標準,因此證實
Bifidobacteria對增進結腸的能動性有其特殊性。 |
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3.Prevention of diarrhea |
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3.預防痢疾 |
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Few studies have been performed. One double-blind study of infants demonstrated that a formula with added B. bifidum and S. thermophilus reduced the incidence of hospital-acquired diarrhea compared to a standard formula. It also lowered the rate of rotavirus shedding into the environment (45). |
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極少研究已被完成,針對嬰兒所作的一項雙重盲目的研究
證實:和傳統標準的飲食做比較,添加了B. bifidum及
S. thermophilus的飲食較能降低hospital-acquired痢疾的發生率
。而rotavirus shedding進入環境中的比例也同時被降低了。 |
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4.Immunomodulating effects |
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4.免疫調整的效能 |
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Ingestion of milk fermented with B. bifidum led to an increase in phagocytic activity in peripheral blood compared to milk consumption (46). A mixture of B. bifidum and L. acidophilus decreased chronic inflammation of the sigmoid colon and increased humoral immunity in a group of elderly subjects (47). |
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攝取使用B. bifidum發酵過的牛奶較直接飲用牛奶比較下,
前者能增進神經末稍血液的食菌活動力。B. bifidum及
L. acidophilus的混合降低了慢性乙狀結腸的發炎及增進個體
體液的免疫機能。 |
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Actobacillus casei: new interest in an old bacteria |
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Actobacillus casei:舊類細菌的新主張 |
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The group L.casei consits of several species of facultatively anaerobic and hetero-fermentative, mesophilic lactic acid bacteria (48). Their metabolism provides organoleptic qualities to several traditional FM and cheeses, and more recently, to new fermented milks. L.casei have been detected in the feces of both infants (49) and adults (50). Their ability to survive transit through the intestinal tract in adequate numbers to have a physiological effect (50), coupled with their potential health benefits make L. casei an ideal candidate for a probiotic. |
L. casei族群包含許多種類兼性厭氧菌和促起發酵嗜中等溫
度且由乳汁取得的細菌結合而成。它們的新陳代謝提供給
許多傳統的優酪乳及乳酪用感官感覺出的品質(種),更
接近者是對新優酪乳而言。L. casei同時在嬰兒及成人的排
泄物中被發現。它們能以足夠的數量(目)經過腸道而存
活的能力頗具生理學上的效能,和其潛在性的健康益處結
合使L. casei成為專業生物的理想候補者。 |
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1.Treatment of diarrhea |
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1.治療痢疾 |
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Several double blind, placebo-controlled clinical trials have demonstrated that oral consumption of L. casei reduces the duration of diarrhea (51), and in particular, rotavirus gastroenteritis (52) in children. In addition, L. casei may help reduce the duration of diarrhea associated with children in day care centers (53), antibiotic treatment (54) and traveler's diarrhea (55). |
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許多安慰劑-寬心丸的臨床試驗證實口服L. casei降低痢疾的
期間,更特別的是兒童的ratavirus腸胃炎。L. casei除了可能
有助於降低兒童在保健中心的痢疾病期外,尚能有助於抗
生治療及居旅者的痢疾。 |
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2.Effects on the intestinal microflora |
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2.腸內的微小植物效能 |
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In addition to increasing lactobacilli count in feces (50), milk fermented with L. casei has been shown to lower the activity of the colonic enzymes B-glucuronidase (50,56), glycocholic acid reductase, and nitroreductase (56) in healthy adults. A recent study demonstrated a decrease in B-glucuronidase and B-glucosidase activities in infants after ingestion of a milk fermented with yogurt cultures and L.sasei. This effect was not found with yogurt alone or with gelled milk (control) (57), thus suggesting that the modification was due to L. casei or to the association between L. casei and yogurt. |
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除了能增加排泄物中點出的lactobacilli外,結合了L. casei的優
酪乳品亦已顯示出降低臨床上B-glucuronidase, glycocholic acid
reductase及nitroreductase在健康成人體內酵素活動力的功能。
一項最新的研究已證實:經攝取由優酪乳菌及L. casei結合發
酵而成的牛奶後,降低了在嬰兒體內的B-glucuronidase及B-
glucosidase酵素的活動力。這項功用無法單獨被適用於酵母
乳或膠化的牛乳,因此建議正為L. casei或L. casei與優酪乳的
結合。 |
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3.Immunomodulating effects |
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3.調整免疫的效果 |
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Challenge tests (e.g., using Salmonella typhimurium) with oral ingestion of L. casei in mice has led to increased protection in animals infected with pathogenic bacteria (58,59).
A few reports using human subjects have shown an enhancement of non-specific immune system activators, such as y interferon and interleukins (ex vivo) (60) and of specific immune responses to various challenges, including rotavirus vaccine (61). |
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挑戰性的測驗(使用Salmonella typhimurium)將L. casei給予
老鼠口服攝取後增加對引起動物感染疾病的細菌之保護力
。
有一些研究報告以人體為對象顯現出增加了不具特效的
免疫系統上之活性劑,例如Y干擾素,interleukins及針對各
種挑戰(包含rotavirus疫苗的)特殊免疫回應的功能。 |
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In a recent study infants with atopic dermatitis were given formula with added L. casei. Not only did the concentration of fecal tumor necrosis factor-a decrease significantly (a measure of the immune response), but clinical symptoms improved as well (62). Viability of the bacteria is an important factor of its effectiveness (61). |
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在新
近的研究中,將添加了L. casei的處方給遺傳性過敏症,皮
膚炎的嬰兒服用。不僅是排泄物的腫瘤疸因子係數濃度明
顯地降低(免疫反應的測量標準),且臨床上的症狀也同
時改善了。生存能力是細菌的影響程度的一項重要要素。 |
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