Author: Herr Dr. Amoneit
Last saved by: Saritas, Sevim
Company: Hewlett-Packard

Physicochemical and Oxidative Properties of Chicken Nuggets 
Enriched with Omega-3 Fatty Acids: Comparison of the Addition of Bulk Fish Oil and Spray Dried-microencapsulated Fish Oil
E. Jiménez-Martín^1, T. Pérez-Palacios^1, J. Ruiz^2 and T. Antequera^1 
^1Department of Food Science; School of Veterinary Sciences, University of Extremadura; Cáceres, Spain
^2Dairy, Meat and Plant Product Technology; Department of Food Science; University of Copenhagen; Frederiksberg C; Denmark

The aim of this work was to analyze and compare the effect of the incorporation of bulk fish oil and spray dried-microencapsulated fish oil as a source of omega-3 fatty acids on some physicochemical and oxidative properties of chicken nuggets. Three batches of nuggets were prepared: a control batch (C), a batch enriched with bulk fish oil (BFO) and a batch enriched with microencapsulated (multilayered microcapsules prepared with lecithin-chitosan emulsions) fish oil (MFO), all of them being deep-fried in sunflower oil. Moisture content, water activity, CIELAB color, lipid content, conjugated dienes, TBARs and volatile aldehydes were determined. Moisture content and water activity were lower in MFO (54.1% moisture and 0.86 a_w) than in C and BFO (both with 57.9% moisture and 0.92 a_w). Color measurement revealed differences between batches, the MFO nuggets showing lower lightness (L*) and higher redness (a*) and yellowness (b*). No differences were detected in lipid content between the different types of nuggets (11.3-12.2%). Lower conjugated dienes were detected in C (0.536 µmol/mg sample) than in both types of enriched nuggets, the values for MFO being lower (0.580 µmol/mg sample) than for BFO (0.653 µmol/mg sample). Lipid secondary oxidation products (TBARs) were significantly higher for BFO (1.83 mg MDA/kg) than for MFO (0.53 mg MDA/kg), which showed the same low oxidative status than C (0.28 mg MDA/kg). Hexanal and 2,4-decadienal were selected as volatile oxidation markers; no differences were found in hexanal areas, while 2,4-decadienal was only detected in the fish oil enriched nuggets, with higher areas in BFO (0.21x10^7 AU) than in MFO (0.11x10^7 AU). Multilayered microcapsules prepared with lecithin-chitosan emulsions provide a protective effect against lipid oxidation of fish oil during the frying process. Thus, the enrichment of chicken nuggets in fish oil with the incorporation of this type of microcapsules can be successfully achieved, obtaining a product with a good stability and oxidative characteristics.