Managing director Mark Duddridge admitted that the impact on the company's sales had been "chuffing annoying" because it has long prided itself on the provenance of its food.
The Callington-based manufacturer makes a range of branded savoury products, including pasties and sausage rolls, using the tag-line "real, honest food".
Between 60% and 70% of its ingredients are sourced from Devon and Cornwall, with most of the remainder coming from UK-based suppliers, with only a small level of imported goods such as pepper.
Mr Duddridge said that the brand had not suffered under previous food scares such as foot and mouth because consumers had responded to the brand's focus on quality ingredients.
But he said the horsemeat scandal had affected consumers' trust in supermarkets, which had, in turn, seen sales drop off in these outlets.
"Horsegate, as people call it, has certainly dented that confidence. Although we weren't involved in it and none of our suppliers or processors were involved in any of that nonsense, I think it has knocked people's confidence in the processed meat products they were buying from supermarkets," he said.
"It was chuffing annoying. It was very different this time. In the past where there have been food issues, what we have found is that people have gravitated to the brand, because it's something they trust, or some of the premium 'own label' products that we make. But in this scare, I think, people were nervous of everything.
"But this week, everything seems to have bounced back. Outside the supermarkets, we didn't really see an effect, but in the supermarkets we did.
"I think part of it was based around people's perception of supermarkets as much as anything."
Ginsters, which started in 1969 as a family-run business making pasties, is part of the Samworth Brothers group and employs 770 people in Callington. As well as making its own branded savoury products, Ginsters also makes products for Tesco and Marks & Spencer.
Sister company and neighbour Tamar Foods makes own label savouries for Marks & Spencer, Tesco, Waitrose and the Co-op.
And in Launceston, sister company Kensey makes desserts for Tesco and Cadbury, while Duchy Desserts makes high-end puddings for Sainsbury's and Waitrose. In total, the group employs 2,200 people in Cornwall.
See Thursday's WMN Business section for news on investment at the Ginsters site and how the company is moving into new markets
