6 replies to this topic

[poppysnoss]

Hi All.

A strange one for you...

Does anyone know what would might cause an "acetic acid-like" aroma in soup three days after production? It's various vegetable soups, like pea, broccoli and tomato soups. The only common denominator is the same batch of onions. The soup normally has a shelf life of over a week.

Thanks in advance

Pops

[Simon]

BUMP for pops.

[Hongyun]

Baterial fermentation from spoilage?

[IPM]

Hi Pops,

Am not 100% sure but usually when you get 'acetic acid like aroma its an indication of microbiological spoilage of some sort. "Acid tolerant bacteria (acetic acid bacteria) are among the main spoilage bacteria because of their ability to grow at relatively low pH and in low nutrient levels. They are strict aerobes and any developments in packaging techniques and materials that increase the amount of oxygen present in the product will increase the incidence of spoilage by these bacteria.
Spoilage reasons tend to be caused by unhygienic processing/handling of products. You need to ensure that your equipment, personnel, raws are handled hygienically.

Hope this assists!!

Irene

[GMO]

Could there have been some fermentation and oxidation following that either of the starting materials or resultant soups? If so, the yeast counts would presumably be higher than normal.

Do they taste acidic? What were the micro results?

[Abdul Qudoos]

What is the pH of soups? Its all depends on pHs


Oxidative stability needs to check for shelf life!


Yeasts and molds needs to perform (but acetic acid kills bacteria, molds and germs that's why people use in traditional pickles/folks recipes where there is no heating/pasteurization takes place)


Acetic acid bacteria which turns alcohol and some sugars in to acetic acid, they are 'acetobacter aceti', perform microbiology!


Numerous studies shows 5 % solution of acetic acid—kills 99 percent of bacteria, 82 percent of mold, and 80 percent of germs (viruses).

[poppysnoss]

Hello All,

Thanks for the replies.

I had been thinking around the same lines - ie acetic acid bacteria. I had very limited data on the product, ie I haven't seen any micro results or know the pH etc as I don't have a sample of this product. It was a query that someone had passed onto me to see if I knew what was going on with it. I did ask for a sample to check, but it has not been forthcoming....