Optimum Conditions For Rennet????? (1 Viewer)

[gezzill]

can somebody please tell me this (pH, temperature and substrate concentration). thanks :]

 

[Minimitt]

Ph ~2 (stomach acidity)
Concentration 1Milk:0Water (so just milk)
Temperature Approx 37degrees celcuis (body temp)

 

[misbahf]

Temperature Approx 37degrees celcuis (body temp)

When I did my experiment at school my rennet worked best at 50 degrees celcius whihc is weird...but it was the same for everyone else in my class.

 

[Minimitt]

it may have seemed as it worked "better" ie it clotted faster at 50degrees, how ever the proteins at such temperatures become 'denatured' you will have seen a yellowish 'tinge' to the milk

also, you have to take into account that you would've bought milk, which even though it says 'full cream milk' it has had chemicals ran through it and watered down.

going to have to remember to try this prac again with milk from my farm before the end of the year lol

 

[misbahf]

it may have seemed as it worked "better" ie it clotted faster at 50degrees, how ever the proteins at such temperatures become 'denatured' you will have seen a yellowish 'tinge' to the milk

also, you have to take into account that you would've bought milk, which even though it says 'full cream milk' it has had chemicals ran through it and watered down.

going to have to remember to try this prac again with milk from my farm before the end of the year lol

That's true but rennin isn't actually found in humans, well it is a bit but we use pepsin to do the same thing rennin does to milk. It is found in the stomach of newborn mammals (i.e. stomach of a cow...calf). I don't think their internal temp is at 37 degrees, perhaps that is why is functions optimally at higher temps.

If the enzyme is denatured it would not be able to initiate the reaction and coagulate the milk since its active site could not accomodate the casienogen protien. I did see a yellow film develpo acroos the top of my milk during the 60 and 70 degree trial. These didn't set.

By the way, i thought all they did to milk was pasteurise it to kill bacteria.

And even if milk is watered down, the only affect that would have is prolonging the reaction.

Also if any chemicals were added, they would not be consumed by the enzyme during the reaction and once the milk had coagulated, the chemicals would just be suspended in the solid.

Good point though, you got me thinking.

 

[Minimitt]

just quick search to see what round abouts for -healthy- cows body temp new it wasnt 37 but approx enough from http://hypertextbook.com/facts/1998/PeiJunChen.shtml
Temp is
40.0 °C38.6 °C37.8 - 38.6 °C37.8 - 39.4 °C38.3 - 39.4 °Cfrom different sources. after a few months the temperatures should balance out to around these temperatures, and calves suckle the mother for atleast that long if not longer.

If you take a glass of "full cream milk" and a class of "fresh farm milk" and take a swig from each, you'll notice a huge difference in thickness, texture, flavour (obvisously), but the viscosity is the main difference to be pointed out. anyrate off topic.



wanna actually look into this more now >_< must focus on other assessments due will do it after lol

good points of discussion though

 

[misbahf]

Thank you.

Hmmm, I'm curious now to see how the experiment would go if farm milk was used.

Anyhow, this is some pretty good stuff to include in my experimental report.