Re: casein

From: "David J. Greiner Jr." <godlike@elp.rr.com>
Subject: Re: casein
Date: Mon, 09 Feb 2004 20:20:16 -0700

> I tried a few different recipes, some I found online and in books. This
> is a hodge podged method I put together through my experiences.
>
> Materials:
> 1 Cup Water
> 1/4 cup Powdered Milk
> 28 % Acetic Acid (or Vinegar or Lemon Juice)
> Ammonia
> Cheese Cloth (or a stocking as I prefer)

I don't know anything about photographic use of casein, but when I saw
this I couldn't resist to hit the reply button. This time, I try to
make something edible out of something photographic.

In the era when much of the foods are made in factories to average
consumer's taste for light, soft texture and flat, non-potent flavor,
you might think yogurt is always a homogeneous solid substance. This
is because yogurt fermented to the fullest extent has shorter shelf
life and therefore is not suitable for retail distribution. So
commercial yogurt is fermented lightly, and may even contain something
like pectin to enhance the solid texture. If you make yogurt at home
from milk, Streptococcous thermophilus and Lactobacillus bulgaricus,
and ferment all the way (typically at 40C for 6 hours -- use a gas
oven with pilot flame, or the oven light might even be enough to keep
the temperature) to make yogurt of rich flavor, the yogurt may be a
bit creamy as it is done, tastes best in day 2 and 3, and start
getting stiff in day 4 and by one week whey is separated and you see a
cheese-like solid of casein. At this point, the yogurt flavor is a bit
more pungent, and it makes excellent sauce to cook chicken, goat or
lamb fricasse. Maybe people from Greece or other places where there
are similar recipes can help here.

So, the idea is, one could use lactic acid fermentation instead of
adding acetic acid to milk, have some fresh yogurt (makes excellent
darkroom snack as it is very visible in red safelight), a nice dinner,
and do whatever with the solid chunk after the yogurt is past its
delicious flavor. Whey from yogurt also adds excellent
sweet-and-sourness when added to home made ice cream, salad dressing,
and other things.

Yogurt is best made from milk that is about 10-20% more concentrated
from whole milk. This is typically done by heating in vacuum chamber,
but it's just as good and much easier to add a pint of dry milk powder
in a gallon of milk. If you use milk made for lactose-intolerant
people, you get sweeter yogurt without adding calories.

Fully fermented yogurt (or milk-acetic acid mixture) is quite acidic,
so there's not much room for bacteria to grow. Indeed, yogurt cultures
themselves (especially S. thermophilus) start dying because of its own
acid secretion. However, this is a good environment for yeast and
fungi to grow, even in the fridge, so the shelf life is fairly short.

--
Ryuji Suzuki
"Reality has always had too many heads." (Bob Dylan, Cold Irons Bound, 1997)