Enrichment of biscuits with microencapsulated omega-3 fatty acid (Alpha-linolenic acid) rich Garden cress (Lepidium sativum) seed oil: Physical, sensory and storage quality characteristics of biscuits

Abstract Garden cress seed oil (GCO) is rich in α-linolenic acid (ALA), and hence is prone for auto-oxidation. Microencapsulation of GCO (MGCO) was prepared in whey protein concentrate with oil/protein ratio of 0.4, by spray-drying method. Microencapsulated GCO powder (MGCO) contained 25 g of GCO/100 g with microencapsulation efficiency of 64.8% and particle size of 15.4 ± 9.1 microns. Biscuits were prepared by supplementing MGCO at 20 g/100 g or GCO at 5.0 g/100 g by replacing flour and fat or fat in biscuit formula. ALA content was found to be 1.02 g and 1.05 g/100 g respectively in MGCO and GCO-supplemented biscuits. Biscuits were packed in metalized PET film (MPET) pouches, stored at three different storage conditions, viz., 90% RH/38 °C for 3 months, 30–40% RH/38–40 °C for 4 months and 65% RH/27 °C for 5 months. Biscuits stored at 90% RH/38 °C had one month shelf- life, whereas at 30–40% RH/38–40 °C and 65% RH/27 °C, they lasted 4 and 5 months, respectively. However, in all the three storage conditions oxidation rate of ALA was high in GCO-supplemented biscuits compared to MGCO biscuits indicating that the encapsulation prevented oxidation of ALA in biscuits. Sensory evaluation results showed that MGCO-supplemented biscuit were acceptable.