Spoiled UHT drinking coconut milk product

Dear Sir / Madam,
Could please anyone help me !
We use direct steam UHT of Tetra Pak for manufacturing drinking coconut milk and now we got a problem about product quality as feature detail :
- Normal Product : drinking coconut milk, pH 6.2 - 6.7
- UHT treatment : 144oC / 4s
- UHT type : Direct steam UHT with Aseptic Homoniser.
- Start production cycle : 16:00 and end at 11:58 am (next day). Total production cycle was 20 hours with UHT AIC at the middle cycle. Only 1 Aseptic Tetra Pak filler TPA Prisma 1000ml.
- Problem : pH fast drop (pH drop to 6.0) at the end production cycle when UHT stop production. It mean that product from Aseptic tank was filled only. QC online regconized the pH drop without incubation.pH drop nearly 100% of product filled from aseptic tank.
- Historical : this is the recurrence issue after 2 moths.The previous issue was disappeared without rootcause finding.Tetra Pak staff also dissembled equipment for inspection but no problem found.
- Micro test result of previous spoilage : Positive gram, rods shape, heat resistance.
- Intermediate product was storage at 60oC after mixing with not exceed 2 hours.
- Loading bacteria of intermediate product TPC < 100 cfu / ml, Thermo spore < 100 cfu / ml
Could you got any the same problem, please share me your case study.
Thanks a lot !

Hi Truongbn,

 

In such instances of problems with sterility it pays to map out the whole production run and events.

 

You should be looking at the product and identifying where you lost sterility and the product failures started. Then look at events just before/at this time to try and identify possible causes of your loss of sterility.

 

Did the pH drop occur only in the packed product or did it drop prior to processing?

 

Kind regards,

 

Tony

Dear Tony,
Thank for your advice, i have sellected more samples for checking & map out whole production time of the issue. I will give you database for support tomorrow. Thanks alot.
Truongbn