Abstract:
To study the antioxidant capacities (AOC) of cinnamon extract (Cinnamon spp.) and use it in frozen ground macadamia filling (GMF). The experiments were divided into 4 parts. Firstly, the AOC by DPPH[superscript O] method and total phenolic contents (Folin-Ciocalteau method) of 3 varieties of cinnamon (C. zeylanicum, C. cassia, and C. burmanni) extracts were determined by varying the solid:liquid ratio (cinnamon powder : absolute methanol) at 1:20 and 1:50 (w/v) and extraction time (4-10 hour) and compared with the synthetic antioxidant BHA. The oxidative stability in macadamia oil (MO) and refined soybean oil (RSO) by Rancimat[superscript (R)] method of the cinnamon extract having the best AOC (120 mg/kg) was compared with BHA. The results showed that the best extraction condition was the solid:liquid ratio of 1:50 (w/v) for 8 h. C. zeylanicum had the highest AOC and was not significantly different from the BHA (p>0.05). The protection factor (PF) of cinnamon extract and BHA in RSO (1.04 และ 1.09) were not significantly different (p>0.05), while in MO BHA (PF 1.14) was found to stabilize better than the extract (PF 0.89). Secondly, the formulation of the GMF was developed and was found to consist of 40% ground macadamia(GM), 5% modified starch, 25% glucose syrup, 10% icing sugar, 19.5% water, and 0.5% cinnamon powder. The moisture content, free fatty acid and total fat of GM were 12.15%, 74.75%, and 0.16% while those of GMF were 27.74%, 1.11%, and 0.14% respectively. The textural properties of GMF were hardness 21.74 g[subscript f], cohesiveness 0.69, adhesiveness 60.00 gf-mm, springiness 0.31, gumminess 14.91 g[subscript f] and chewiness 4.66 g[subscript f]. The color values (L[superscript *], a[superscript *], and b[superscript *]) were 31.18, 9.13 and 20.87 and a[subscript w] was 0.822. Thirdly, the optimum of temperature of cryogenic freezing (-20℃ and -3℃) GMF were determined and the best condition was freezing at -20℃ for 102.6 sec. Finally, the changes in chemical, physical, microbiological, and sensory properties of the GMF during storage at -18℃ for 6 months were studied. It was found that no rancidity was detected, TPA and color were not singnificantly different from the fresh GMF and the total aerobic plate count , yeast and mould were conform with in the standard of Thai dessert, and sensory quality was accepted.