Process contaminants in battered and breaded foods prepared at public food service establishments

Abstract

Acrylamide is a process contaminant already regulated in Europe whereas the toxicological effects of certain heat-induced furan derivatives such as hydroxymethylfurfural (HMF) and furfural are still under revision. Acrylamide, HMF and furfural content were evaluated in 113 coated fried foods provided by food services (restaurants and school canteens). Sampling included battered and breaded foods intended for frying and were grouped according to meat-products (ham & cheese, chicken nuggets), fish-products (fish sticks, fish fillets), seafood (squid rings), vegetables (onion rings), and doughs (croquettes). Acrylamide ranged between 23.8 and 130.4 μg/kg, HMF between 0.11 and 16.07 mg/kg, and furfural between 0.01 and 1.04 mg/kg. Presence of these compounds was mostly restricted to the outer part of foods (coating material), since browning reactions are sped up in the crust. Onion rings showed a significantly higher concentration than the other samples being studied. Home-style (freshly made) chicken nuggets exhibited significantly lower acrylamide content than frozen par-fried nuggets from an industrial source. This finding suggests that increasing the complexity of the formulation of the coating through the introduction of ingredients or additives aimed at improving palatability might lead to the development of heat induced process contaminants. As a consequence, the increase of harmful compounds during thermal treatment of coated food should be carefully considered during the industrial formulation of coatings. Although the recent Regulation 2017/2158 for acrylamide does not mention specific values or mitigation strategies for coated foods, its contribution to daily acrylamide exposure within the population must not be dismissed. This study involves the first systematic prospective evaluation of process contaminants in real operative conditions at food services in Spain.