| 摘要 |
A shallow stream of melted butter is run in laminar flow through a channel where it is fully penetrated by microwave irradiation, pref. at a frequency of 2.45 GHz. The energy imparted to the butter is controlled to limit the rise in temp. to several deg.C only, pref. not more than 6 deg.C. This irradiation results in the butter fat floating on top of a layer of proteins and water. Sepn. by decanting is effected in at least two, pref. three, successive stages. The irradiation channel is pref. made of a material which is permeable to the microwaves, esp. PTFE, and is housed in a casing of material which is impermeable to microwaves, partic. stainless steel. Temp.-rise due to irradiation is pref. detected by sensors at the inlet and outlet of the channel. Their signals can control the energy supplied by the microwaves. Used in prodn. of a virtually anhydrous butter fat exempt of proteins. This is a prod. which can be stored for long periods without refrigeration, simply by excluding oxygen. |
