Speaking at a misconduct hearing Read he didn't know the carrots were scanned twice when at the self-service till, the Daily Mail reported.
Read denied he was only paying around £4(NZ$7.61) for the items as opposed to the full price of just over £14 (NZ$26.65).
When asked if he intended to steal the donuts, Read told the hearing in 'Absolutely not, and I'm horrified we're in this situation here today.'
CCTV footage was shown at the hearing which showed Read's movements within the store.
It showed Read choosing his doughnuts, picking up two carrots and placing them in a small white Krispy Kreme bag.
The barcode was then printed for the carrots by Read.
He then continued with his shopping.
At some point while off camera, PC Read placed the carrot barcode sticker on to the box of Krispy Kreme doughnuts, the Daily Mail said.
"Which he said was to free up his right hand in order to pick out a sandwich and drink."
According to Read the carrots were purchased as a joke for a fellow officer.
"I had placed the carrots in the Krispy Kreme bag to disguise the fact that the contents of the bag were part of a joke.
"In the same way, I did not wish to place the sticker on to the bag and effectively signpost what was inside, and therefore give the gag away."
After finishing his shop, Read walked to the self service till where he scanned and paid for the items.
CCTV footage show him scan the carrot barcode place to the side of the Krispy Kreme box first, and placing the bag of carrots in the bagging area.
The sandwich and the drink were scanned, before appearing to finally attempt to scan the box of doughnuts again.
Read claims the CCTV shows him placing the box down on the metal till and reaching inside his left pocket, where he keeps his phone.
"I cannot recall why I did that. I can only suggest that I had felt it vibrating, and I wanted to check whether it was a call, or whether it was a text I could look at later."
The box of doughnuts was then placed into the bagging area where he the paid for his shopping.
"I didn't check the screen to see if the doughnuts had scanned through.
"I wish I had done now. I wish I had paid more attention to what was otherwise an ordinary experience - going into the shop, scanning the items, and then paying" Read said.
An embarrassed Read said 'this has been a very long and lengthy nine months, not being at work when I should be.'
Carolina Bracken, defending, said Read had an 'unblemished career' before the incident, stating he had been involved in policing Donald Trump's visit to Blenheim Palace and several royal weddings while serving with Thames Valley Police previously.
"Who would be suspicious of a police officer?" Bracken asked.
However, the panel decided that Read breached two professional standards of discreditable conduct, and of honesty and integrity.