Post
by redzed » Mon Mar 19, 2018 06:31
Good point Eric. It's been a while and I think we all learned a lot more since then. And the thing is that the more you learn about this craft you realize how little you know. I read about being cautious regarding the length of time you keep the bacteria in the water in an article in Science Direct, but did not make any notes and will have to search for it. It appears that the primary reason that we mix the culture with water and then add to the batter is to expedite its distribution. No "lag phase" is necessary. Here are a couple of exerpts by Gerhard Feiner from his professional book Salami - Practical Science and Processing Technology
Freeze-dried cultures can be mixed for around 15-30 minutes in cold water before being
introduced into the salami mass to make them faster acting but this is not essential.
Premixing with water makes supports an even introduction into the sausage
mass as the amount of starter cultures used per batch of salami, without water, is
rather small. If premixed with water, deminerialized water should not be used as
cells would die by bursting in this type of water. The bacteria can, as said earlier,
be premixed with water for around 15-30 minutes before use, rather than for a
period of hours, as some degree of unwanted activity or fermentation would
take place during this period of time. Types of sugar, such as glucose, are predominantly
the carriers used in commercial starter cultures, and so if the culture
was soaked for too long, it would start to ferment the sugars present.
Around 1010-1012 of bacteria are added per 100 kg of salami and these 1012
bacteria only weigh around 1 g on their own. Therefore, carriers are used as they
make starter cultures easier to handle.
Starter cultures are introduced into the sausage mass at the beginning of
the cutting or mixing process and they must be evenly distributed. Uneven
distribution results in nonuniform acidification and therefore faulty products.
Freeze-dried or frozen starter cultures should be stored at -18 to -25°C
until use and should not be premixed with other additives such as sugars, GDL,
ascorbate, spices, and salt before use. If premixed with other additives 1 or
2 days before being added to the sausage mass, some moisture is always present
and as soon as the starter cultures have access to humidity, temperature, and
some food (such as sugars), fermentation would begin and faulty salami would
be the result. The acid produced by a starter culture premixed with other additives,
even if the premix were stored in a chiller, would be sufficient to react
with nitrite and the salami would be discolored as a result. The acid produced
within the premix would subsequently be missing inside the salami and insufficient
acidification will take place leading to microbiological spoilage of the
product and a risk of food poisoning. These vital points explain why complete
blends or premixes of additives containing starter cultures for the production of
salami do not exist.