[Best of Quora][食品]为什么食用蓝奶酪中的霉菌是安全无害的?

----题外话----

Quora作为社交问答伟大的先行者,于日前出版了《Best of Quora 2010-2012》,其中汇集了生活中18个分类下的132个精彩答案,一共400多页。

出于对Quora的喜爱以及对Quora团队的尊敬,我会陆续将这本书的内容转贴到这个晓站里。
暂时应该都是原文转贴,如果我后续的业余时间够充裕的话,我打算陆续翻译一部分。

在这里也招呼一下略晓上的英语达人,是否想以志愿者的身份帮助共同翻译下,于己于他都不无益处。

mainqimgc2d1417f2893f8b75898e08ce8ed189b

mainqimg8319946f8355d22508cbacd2f0c268f8

mainqimg1eac87d30d4d2464b71555f6c0dac735

3 个回答

Generally speaking, the aversion from mold in foods comes from the cognition that mold on fresh foods clearly indicates that they are no longer fresh. We also assume that food would not taste the same because a fermentation has began to take place -usually accompanied by change in appearance, texture and aroma of the food in question. Many molds simply taste unpleasant yet are not problematic to our bodies. Dangerous moulds are those which produce mycotoxins and aflatoxins. These toxins may effect our respiratory system and in some cases even act as carcinogens. Not all molds produce these toxins.

Penicillium Roqueforti and Penicillium Glaucum which are the blue molds used for cheese, cannot produce these toxins in cheese. The combination of acidity, salinity, moisture, density, temperature and oxygen flow creates an environment that is far outside the envelope of toxin production range for these molds. In fact, this is true for almost all molds in cheese, which is the reason that cheese has been considered a safe moldy food to eat over the past 9,000 years. Not only is it safe but it can also be healthy (P.Roqueforti and P.Glaucum have natural antibacterial properties and ability to over-take pathogens. Moreover, our bodies use a variety of wild flora for digestion, development and immune systems).

Unfortunately, mass food manufacturers have run relentless campaigns over the previous few generations to cause consumers to conclude (beyond their 9,000 years of wisdom) that plasticy looking bright-colored food-like substances with homogenous texture, in a vacuum-pack and big brand logo = equals controlled/safe product. Anything moldy, rustic, irregular, inconsistent or natural = equals unsanitary conditions, primitive family farming, or uncontrolled production. Today we understand that this is not the case as we go back to traditional and artisan foods -and stay away from highly processed industrial food replacements.

Blue Molds - have a particularly unique effect on cheese. They accelerate two processes dramatically: Proteolysis (breakdown of proteins), which causes the cheese to take on extra-creamy texture (especially in proximity to the blue mold veins), and lipolysis (breakdown of fats), which makes up the tangy, spicy, sharp and strong flavor. The creamy texture stand up to the sharp flavor and together they bring upon an exciting flavor/texture/aroma profile, which is often further balanced against sweet/nutty milk and lots of salt (Blue cheeses typically contain twice the salt of other cheeses). This combination is so unique - it is unlike any other food!

The Process:
Before going into the second part of the question ("can one "bleu-ify" other cheeses at home?") let's just understand the process in a nutshell:
Blue mold grows only during a specific time frame within the aging period. It needs a balanced acidity, so it can't grow on the cheese if is too young and still acidic. It also relies on nutrients which are still readily available in the cheese -so it can't be too late when the cheese is already aged.
The mold spores are highly contagious to other cheeses so blue cheeses typically would not share aging space with other cheeses during this sensitive period.
The cheese is usually pierced with a thick needle first so that oxygen will flow into its crevices and kickstart the growth. The cheesemaker would repeat this process every 7-14 days until sufficient growth of blue has taken place.
At this point, the cheese is wrapped in foil to prevent the blue from growing out of control. The cheese is then immediately moved to cooler temperature and aged for the remaining period, allowing the processes of proteolysis and lipolysis to take place and develop deep and complex texture, flavor and aroma. In some cases this last stage could take up several months past the development and stoppage of the blue mold.

Bluing Cheese at Home:
Trying to blue an unsuspecting cheese at home may prove difficult. The cheese you purchase is often already aged, ripe and stable. It lacks sufficiant nutrients to support the growth of new blue mold. Competition from other well-established molds and yeasts in the rind may be too much for the blue to overcome at such late stage.

Having said that, this is not an impossible experiment. One just needs to find a cheese that is very young and has little or no rind. It must be moist enough to support the growth of this mold, yet it firm enough to enable the puncture a hole through it with a knitting needle. To "blue" it, one would need blue mold (can be purchased or scraped off moldy rye bread or another blue cheese, or simply pulverize a piece of blue cheese in a blender with a little bit of water and a pinch of salt). The procedure would be to sanitize a knitting needle or metal skewer and dip it in the mold to "contaminate" it with blue. Use it to pierce the cheese through from both ends to assure ample mold seeding and clear air passages. Set the cheese on its side so air can flow through it. It is best to start it at about 55°F or 13°C (temperature of a wine cooler) with high humidity (90%-95%). When the growth of blue is sufficient (1-3 weeks) wrap with foil and move to the fridge for a few more weeks or months. In theory this should work but blue cheese are finicky and tricky to get right. Many variables may still fail it.

Above: Blue Stilton cheese is being pierced manually. In a more industrial settings, a piercing machine is used for fast piercing at perfect angle and distance

Above: Young Roquefort cheese in the Roquefort sur Soulzon caves, are resting on their side to enable the flow of moist air into its holes and piercings -so the blue mold begins to take hold. One can see early blue spotting developing on these.

Above: Roquefort cheese is being wrapped in foil to stop the growth of blue before it takes over.

Above: Rye bread left in the cheese caves of Roquefort sur Soulzon to mold and help the nearby cheese develop by releasing spores into the air

Above: The perfectly straight 90° lines of blue mold in this Gorgonzola cheese are not accidental; these are the traces of where needles were used to pierce it.

原文链接

臭豆腐臭中有奇香,就是一种产生蛋白酶的霉菌分解了蛋白质,形成了极丰富的氨基酸使味道变得非常鲜美,臭味主要是蛋白质在分解过程中产生了硫化氢气体所造成的。其他的腌制已经发酵类食物都是利用这般原理(酸菜、豆腐乳、腌肉、酸奶)
一般食物长了霉菌就意味着变质,但是很多软质奶酪都是生长霉菌的,附在其表面或者内部。霉菌利用奶酪中的营养物质生长,但是同时也改变了奶酪的风味甚至口感,在奶酪内部成长的霉菌既为蓝色霉菌,称蓝纹(Bleu)奶酪,又名“蓝芝士”,非常著名。

很多世纪以前,一些奶酪被放在阴凉潮湿的山洞里储存成熟,使得这些奶酪当中自然形成了一种蓝绿色的霉菌纹理。相比使奶酪腐烂变质,这些霉菌最大的好处是给奶酪增加了一种独特的刺激性口味,深受人们的喜爱,蓝芝士也由此产生了。从此,奶酪制造者学会了刻意将霉菌孢子加入到制作的奶酪中,许多奶酪至今还保留着在山洞里储存成熟的加工过程。蓝芝士随着存放时间的延长,其“臭味”也逐渐浓烈,但最好还是尽快食用。
现代工艺制作的蓝芝士都是用路凯夫青霉菌Penicillium Roqueforti或格劳卡姆青霉菌Penicillium Glaucum接种,再轻轻挤压后的凝结物制作而成,而后霉菌在储存过程中不断生长。这些奶酪具有明显的蓝色纹理和独特的风味。它们的质地可以或软或硬。
29219ec64cec692799b6326d224cf9d0

蓝芝士像咱们中国人的臭豆腐一样,虽然具有一股“臭味”,但还是受到许多人的钟爱,且食用方法有很多。

为什么能食用,我觉得和真菌一个道理,大多数真菌是有益的,而且具备很高的营养价值,一些病变的霉菌产生了有毒物质并且破坏了食物的营养价值改变风味状况,所以不可食用。青霉素作为一种恰恰不产生毒素,讲牛奶中蛋白质分解成易吸收的氨基酸,形成大理石花纹般的蓝绿色纹路,味道辛香浓烈,很刺激。深受饮食爱好者的喜欢。
但是放久了会进一步”腐化“,并且会产生新的其他有毒霉菌,不便于再食用。
在真菌里也存在斗争关系,都是种族抢渡营养的过程,来壮大自己的菌群。在制作食物上面需要高度灭菌,并且接种,从而将其他细菌或真菌排除再外...

这种问题我还真是不专业,不过的确有这种情况,有些菌类的确是可食用的,而且有的时候是专门来食用这用菌类的

你的回答