Topic: Flavour Enhancers

[Peripatetic Phil]

Good to see some real science here, Piscator -- welcome !
** Phil.

[Garp]

Brilliant Piscator. 

Perhaps you could enlighten us on the marination of chicken using either yogurt or lemon juice 

[Piscator]

Brilliant Piscator. 

Perhaps you could enlighten us on the marination of chicken using either yogurt or lemon juice 

To understand the process of marinating meat properly you need to understand a bit about the composition and structure of muscle, which is a pretty meaty topic  ;D (see what I did there) involving quite a bit of complex biochemistry.
In as simple terms as I can think to use - to imagine what muscle structure looks like, take both hands and hold them out in front of you with your palms facing you.
Now interlace your fingers so that your fingertips reach the second knuckle - this represents the muscle fibres. Muscles contract or relax by sliding the filaments - slide your interlaced fingers back and forth and you'll get the idea. This process requires energy - the ATP stuff I mentioned previously (see how this is coming together now?).
When an animal is slaughtered the supply of ATP runs out (how long this takes depends on certain reserves the animal had) - this results in the sliding filaments locking together and becoming fixed... normally known as rigor mortis. If you look at your interlaced fingers you will see that where they overlap the fibres are more dense and therefore the meat here is tougher. Ageing meat allows the fibres in the less dense bands to break down and weaken making the meat easier the shear in that region and therfore more tender.

As the ATP in the muscle runs out the pH in the meat drops to about 5.0.
Most natural yoghurt cultures these days are self limiting at a pH of about 4.3 - 4.5, whereas if you went back to the 80's, yoghurt cultures weren't selected for self limiting strains in the same way and tended to be slightly more acidic and tangy, probably tending to run closer to 3.8 - 4.0 or slightly lower depending on the fermentation conditions used.
Freshly squeezed lemon juice has a much lower pH at around 2.0.

Both yoghurt and lemon juice work in the same way by using their acidic pH to break some of the cross links and open up the fibre structure and let the marinade into the meat. Lemon juice needs less time to do the job than yoghurt as it is much more acidic but both essentially do the same thing to the meat.

I'm not getting drawn into any debates, just explaining what is happening 

[Peripatetic Phil]

For perhaps the first time ever, I now think that this forum would benefit from a "thank you" button ...
** Phil.

[Invisible Mike]

Good evening from a fellow Piscator!

I agree with Phil's comment there, that is very interesting stuff! May I ask, do you have a professional food science background or is that info that you've researched online etc? I am in no way questioning the accuracy of what you say btw I'm just interested.

Regards

Mike

[Garp]

I wish I hadn't asked now - my head hurts.

But, as Phil and Mike- say ..... thanks

[Piscator]

Hi Mike,
Yes - trained as a food scientist with just over 20 years in the industry working with a wide range of foods including red meat (abattoir, cutting and retail), dairy (milk, cheeses, butter, ice-cream, yoghurt, millkshake and various others), fruit and beverages.

Nice avatar 

Sorry Garp 

[Invisible Mike]

Wow! Excellent!..and thanks...  Please keep contributing! 

[Micky Tikka]

Interesting
thanks P

[Peripatetic Phil]

See also today's Guardian on "Neuro-cuisine