Composition, antioxidant properties and microbiology of nutmeg ground by three procedures

Abstract

Composition, antioxidant capacity, and microbial loads of nutmeg ground by ambient, chilled, and liquid nitrogen methods were studied.

The particle size (modulus of fineness) and the percentage of moisture were not different (P>0.05) between the three types of ground nutmeg. The percentage of steam volatile oil in nutmeg ground by the ambient method (5.8%) was different (P<0.05) from that of nutmeg ground under colder conditions (chilled and liquid nitrogen, 5.4%). The percentage of steam volatile oil in nutmeg ground by the chilled method (5.5%) was not different (P>0.05) from that of nutmeg ground by the liquid nitrogen method (5.3%). An interaction between grinding method and batch was detected for percentage of oleoresin. The oleoresin color equivalent of nutmeg ground by the chilled method (0.748 g/100 ml) was different (P<0.05) from that of nutmeg ground by the liquid nitrogen method (0.969 g/100 ml). The oleoresin color equivalent of nutmeg ground by the ambient method (0.902 g/100 ml) was not different from that of nutmeg ground under colder conditions (chilled and liquid nitrogen, 0.859 g/100 ml).

The addition of 2.5% nutmeg was found to have a slight antioxidant effect when tested in a model salad dressing. Antioxidant capacity was not different (P>0.05) between the three types of ground nutmeg.

Standard plate counts were not different (P>0.05) between the three types of ground nutmeg. Yeast and mold loads were different (P<0.05) between the three types of ground nutmeg. Nutmeg ground by the ambient method tended to have higher microbial loads than that ground by either chilled or liquid nitrogen methods.