The determination of moisture in plain cakes by a microwave attenuation technique

Abstract

A procedure based on microwave attentuation measurement with an A.E.I. Ltd. moisture meter has been developed for the rapid determination of moisture in plain cakes. The main factors influencing attentuation, apart from moisture, are temperature, sample preparation and cake texture. Under the conditions described, linear relationships were obtained between moisture content, attenuation and temperature for a variety of cakes. At moisture levels ranging from 18 to 25 per cent., 95 per cent. of the results obtained by the microwave method were within &0-6 per cent. of results obtained by a Brabender oven method.

Microwave absorption capacity of rice flour. Impact of the radiation on rice flour microstructure, thermal and viscometric properties

“…This indicates that the microwave absorption capacity of flour does not depend on water activity since the attenuation increased drastically even when a w hardly varied around a w =1, but depends on the total water content of the flour. These results also indicate that the attenuation and the phase shift measurements may be a fast, simple, and accurate method for determining in line the moisture content of rice flour as they allow a remote and non-destructive measurement of the flour, as concluded by Ince and Turner (1965), in biscuits investigations and Okabe et al (1973), in rice and wheat grains study.…”

Structuring gluten-free systems: effect of formulation and physical modification of ingredients

“…This indicates that the microwave absorption capacity of flour does not depend on water activity since the attenuation increased drastically even when aw hardly varied around aw=1, but depends on the total water content of the flour. These results also indicate that the attenuation and the phase shift measurements may be a fast, simple, and accurate method for determining in line the moisture content of rice flour as they allow a remote and non-destructive measurement of the flour, as concluded by Ince and Turner (1965), in biscuits investigations and Okabe et al (1973), in rice and wheat grains study. The evolution of the temperature and the water content of the flours during MWT are shown in Fig.2.…”