ศูนย์นวัตกรรมเทคโนโลยีหลังการเก็บเกี่ยว

Study on drying characteristics of macadamia nuts.

Toyoda, K.; Shibata, Y.; Mwangi G. G.; Takeuchi, R.; Kojima, H.;

Japanese Journal of Tropical Agriculture Year: 1991 Vol: 35 Issue: 2 Pages: 92-97 Ref: 10 ref.

1991

บทคัดย่อ

In order to avoid deterioration of macadamia nut's superior nutty flavour and crisp texture, the drying process of macadamia nuts must be carried out carefully through several steps in postharvest processing. Equipment for analysing the drying characteristics of macadamia nuts was designed, consisting of a drying oven with an air circulator, an electric balance and a hot-wire air velocity meter. The drying characteristics of macadamia nuts were analysed through drying experiments with air heated at 50, 70 and 90 deg C. Two drying equations, an exponential model and a 2-tank model, were evaluated to predict the drying process. It was found that the drying characteristics of macadamia nuts could be more accurately represented by an exponential drying model. Parameters in the drying model, drying constant and equilibrium m.c., were estimated by the SALS program. Physical properties of the nuts were also analysed. Nut weight, diam. (3 dimensions) and ratio of dry weight of shell to whole nut were measured. It was found that macadamia nuts are nearly spherical and there is a good correlation between the values of the equivalent sphere diam. and nut weights. Mean ratio of dry weight of shell to whole nut, alpha , was 0.688 for sound nuts and 0.714 for those damaged by insects, resp.