Mrs Balle contacted Heinz Wattie's, not so much to complain, she said, but to notify the company because she felt the incident might warrant a recall of that particular batch.
After being moved on to a number of people and then ignored, she said, the family paid $400 to have the object independently tested.
"I wanted to know what it was ... because I feed it to my baby. If I buy it, I need to be able to trust it and now I don't trust it."
An Environmental Science & Research certificate of analysis showed that the object - 8.3mm long, 1.4mm wide and 0.2mm thick - was a form of plastic.
The certificate, signed by food laboratory manager Darren Saunders and technician Shirley Jones, said: "The sample was submitted to a forensic scientist at ESR Mt Albert, Auckland, for infrared spectrometric examination. The piece of plastic was identified as a cellulose-based plastic, such as Cellophane."
Heinz general manager of quality and risk Paddy O'Brien confirmed the company had received calls from Mrs Balle. He said it had arranged for a representative to collect the object, but Mrs Balle changed her mind.
"The problem is that we haven't been able to conduct an investigation into the whole thing because we've never seen the evidence at all.
"We've never heard from the health authorities. There's pumpkin skin, there's onions in there - and onion skin looks very much like plastic at times - so we would have liked an opportunity to test it ourselves."
