Physicochemical Properties and Sensory Evaluation of Wheat-Purple Rice Biscuits Enriched with Green-Lipped Mussel Powder (Perna canaliculus) and Spices

Biscuits are one of the most consumed bakery products eaten by everyone. Purple rice contains much higher levels of antioxidants, vitamins, and minerals such as iron and zinc compared to wheat. The aim of this work was to produce a protein-rich biscuit made from purple rice flour and defatted green-lipped mussel powder (Perna canaliculus) (0–20%) blended with ginger and galangal spices at 4% for each spice. The objective was to produce an inexpensive, balanced, healthy snack product containing increased levels of protein and antioxidants from the mussel powder and to investigate the consumer preferences of these biscuits using the four different ethnic groups (Thai, Chinese, Caucasian, and Pacific Islanders) living in New Zealand. The addition of the mussel powder increased the crude protein content by 43% and the protein digestibility by 21% at the highest level of inclusion. The addition of mussel powder significantly (p<0.05) increased the hardness of biscuits while making small increases in the browning index of the cooked biscuit. The phenolic contents and antioxidant activities (DPPH and ABTS) were significantly (p