pH PH and Oxidization

[cydtrak]

Hi All,

Absolute newbie here in terms of food science, so pardon my ignorance.

Currently in the process of trying to tweak a hot sauce idea using fresh pomegranate juice. Towards the end of January I made a batch which appears to be going dark on the top of the bottles. Reading through posts it sounds like oxidization (see attached picture)

- The hot sauce has 13% Lime Juice & 6% White Wine Vinegar for acidity
- I'm using pomegranate, orange and grapefruit juice as the base (and xantham gum)
- Have been doing the hot fill method for bottling and then dipping in hot wax.

Questions I'm hoping someone could answer:

- If I pop the lid and there is no fizz, taste/smell is good - can I do a PH test at the point to confirm it has not spoiled etc? Or is it to late at this point for PH accuracy?
- Does oxidization occur quicker because the colour of the base it lighter (I.e. almost pink to light red)?

 

[Jadan]

Ive never gotten oxidation like that, I assume you just recently bottled? I think you have a lot of fruits and fruit juice that is high in sugars, so it might have altered your fermentation, and brought up your pH levels. I always do a pH test as I make the sauce and get it to around 3.4 for most things I make. That keeps it very shelf stable.

 

[The Hot Pepper]

Oxidation would usually occur once it has been opened, with the introduction of oxygen. This could mean it has not been properly sealed and oxygen is entering. However there was a recent thread on this also, see if this helps::

shipping - Sauce darkens aftdr shipping

Have you all experienced any issues with your sauce darkening due to shipping? If so what solutions have you found. My sauce tends to darken on a long journey and in at least one case resulted in change in flavor

thehotpepper.com

 

[cydtrak]

Oxidation would usually occur once it has been opened, with the introduction of oxygen. This could mean it has not been properly sealed and oxygen is entering. However there was a recent thread on this also, see if this helps::

shipping - Sauce darkens aftdr shipping

Have you all experienced any issues with your sauce darkening due to shipping? If so what solutions have you found. My sauce tends to darken on a long journey and in at least one case resulted in change in flavor

thehotpepper.com

Got you! Ok then the batch has probably got some issues going on.

 

[cydtrak]

Ive never gotten oxidation like that, I assume you just recently bottled? I think you have a lot of fruits and fruit juice that is high in sugars, so it might have altered your fermentation, and brought up your pH levels. I always do a pH test as I make the sauce and get it to around 3.4 for most things I make. That keeps it very shelf stable.

This was bottled about 3 months ago from memory. I should have maybe made the post clearer - this is a cooked sauce and is not a fermentation hot sauce (my concern is it is fermenting without intention). PH test was good around 3 on the digital and also paper.

 

[The Hot Pepper]

That may be a layer of separation. Try to investigate without shaking it. Try to get a "core" sample. Stick a knife in there and core out a sample to see if it's darker in the middle or simply separation.

 

[The Hot Pepper]

Or tap the bottom on the the heel of your palm to see if it shifts back down. If so, just a layer of separation.

 

[cydtrak]

Or tap the bottom on the the heel of your palm to see if it shifts back down. If so, just a layer of separation.

Thanks Admin! Another suggestion I will try shortly.

 

[Downriver]

Other thoughts....

Given everything you've said, I'd focus on headspace. The bottle in the pic has a little too much headspace for my liking.

What causes headspace? Two things I think of are 1) not filling the bottle up close to the top, and 2) whirring and stirring (blending) the sauce, then immediately bottling it. Whirring and stirring introduces a LOT of oxygen into the sauce. Over time, that oxygen will move to the top of the bottle, increasing headspace and potentially causing oxidation. To minimize this, I create the sauce, whirring and stirring it, etc. Then, I refrigerate the finished sauce for 24 hrs, which lets it settle and the excess oxygen escape. After that, I just bring the sauce back up to temp (with minimal stirring) and process.

Is this batch bad? Maybe, maybe not. My guess is it's fine. I'd just shake it up and move on, but do the other things Boss suggested, just to be safe.

Just some thoughts. ymmv.

 

[cydtrak]

Thought i would update here: I think Downriver's suggestions might be accurate. To ensure no unnecessary fermentation is occurring:

- Opened a new bottle
- Put lid back on and left on a shelf (not in the the fridge)
- Reopened the bottle 2 weeks later

I encountered no bubbling or fizz. Taste is fine, as is the smell.

As for Admin suggestions, I did a tap test and the sauce did shift back down.

Moving forward I will attempt to fill the bottle to the top and avoid the introduction of unwanted oxygen.

 

[cydtrak]

Other thoughts....

Given everything you've said, I'd focus on headspace. The bottle in the pic has a little too much headspace for my liking.

What causes headspace? Two things I think of are 1) not filling the bottle up close to the top, and 2) whirring and stirring (blending) the sauce, then immediately bottling it. Whirring and stirring introduces a LOT of oxygen into the sauce. Over time, that oxygen will move to the top of the bottle, increasing headspace and potentially causing oxidation. To minimize this, I create the sauce, whirring and stirring it, etc. Then, I refrigerate the finished sauce for 24 hrs, which lets it settle and the excess oxygen escape. After that, I just bring the sauce back up to temp (with minimal stirring) and process.

Is this batch bad? Maybe, maybe not. My guess is it's fine. I'd just shake it up and move on, but do the other things Boss suggested, just to be safe.

Just some thoughts. ymmv.

Question regarding bottling - from a commercial production perceptive, there are no issues with cooking sauce, letting it cool and then reheating for bottling purposes?

 

[The Hot Pepper]

Moving forward I will attempt to fill the bottle to the top and avoid the introduction of unwanted oxygen.

No!

 

[The Hot Pepper]

If you hot-fill-hold correctly the headspace acts as an airtight hermetic seal. Do not fill to the top. No good!

 

[cydtrak]

If you hot-fill-hold correctly the headspace acts as an airtight hermetic seal. Do not fill to the top. No good!

Noted!

 

[The Hot Pepper]

Are you inverting for two minutes?

 

[salsalady]

Question regarding bottling - from a commercial production perceptive, there are no issues with cooking sauce, letting it cool and then reheating for bottling purposes?

There are no issues to cook-cool-reheat-bottle as long as proper cooling and heating procedures are followed! Shallow pan or ice bath to cool, heated up to temp in the proper time, stir to avoid scorching....


For bottle filling- If the sauce is very aerated due to blendering, I sometimes have trouble with the bottles looking short filled when the oxygen comes out of the sauce in the bottle. I try to make sure the sauce is stirred down, work the foam or froth out before bottling. I fill up to or SLIGHTLY ABOVE the neckring of the bottle. Not to the very top. When it cools, it looks like a properly filled bottle and not a short-fill.

Good luck and Have Fun!
SL

 

[cydtrak]

Are you inverting for two minutes?

for my last crack at this, no I didn't. I'm going to make sure we do that next time. I did make another smaller batch that included more vinegar, sugar, salt and a small amount of citric acid.

The colour looks amazing! Just need to adjust the amounts of each as the pomegranate is getting lost in the sugar/vinegar.

 

[cydtrak]

There are no issues to cook-cool-reheat-bottle as long as proper cooling and heating procedures are followed! Shallow pan or ice bath to cool, heated up to temp in the proper time, stir to avoid scorching....


For bottle filling- If the sauce is very aerated due to blendering, I sometimes have trouble with the bottles looking short filled when the oxygen comes out of the sauce in the bottle. I try to make sure the sauce is stirred down, work the foam or froth out before bottling. I fill up to or SLIGHTLY ABOVE the neckring of the bottle. Not to the very top. When it cools, it looks like a properly filled bottle and not a short-fill.

Good luck and Have Fun!
SL

Very interesting! I'm also wondering if how we introduce xantham gum is also causing unwanted oxgyen into the mix. Typically we do this with a stick blender at the end of the cook. Any thoughts on this?

 

[salsalady]

I just checked your first post. No other ingredients than what is posted? Usually there is some salt or even a bit of sugar...?

Normally, I mix the xanthan with other dry ingredients, not just add it straight to the sauce. Xanthan has a tendency to lump up if not mixed in properly. Then you may be boatmotoring excessively to get the xanthan mixed in...then over aerating.

Hopefully you have the recipe down exactly to grams, everything by weight. Even the liquids by weight. Mixing even a little bit of sugar and/or salt with the xanthan as dry ingredients, then add to the sauce will help blendering in the ingredients without needing the boatmotor. I normally use a regular wire hwisk. (just a joke on hWheatThins, and hWiskey )

An ingredient that may add sweetness without the sugar, and will also add purple color is beets. You will still have to address how to incorporate the xanthan without over mixing.

I don't have a problem adding xanthan at the start of the process. I don't add it at the very last. Maybe, since you have the whole recipe in grams... ...mix a portion of the liquids with the xanthan and when it is all happy and gloopy and not lumpy, add that to the rest of the batch where it will all blend out and become just the right consistency.

Good Luck and HAVE FUN!
SL

 

[The Hot Pepper]

The colour looks amazing! Just need to adjust the amounts of each as the pomegranate is getting lost in the sugar/vinegar.

You can buy pomegranate molasses, it's just pomegranate boiled down to a syrup, it's delicious and used in Middle Eastern cooking. Don't overpay. If you have a Middle Eastern store it's like $3.99 for a big bottle!