In the present study, the effect of irradiation, storage, and freeze drying on grapefruit bioactivecompounds was investigated. Grapefruits were exposed to one of two irradiation doses: 0 (control)or 300 Gy (
137Cs, a proposed treatment against fruit flies) and then stored for up to 6 days. At thelast storage time point (6 days after harvest), grapefruit pulp from control and irradiated fruits wasfreeze-dried. Bioactive compounds were extracted from Rio Red grapefruit pulp and analyzed withreverse phase liquid chromatography while volatile compounds were analyzed using gas chromatography. Freeze-dried pulp from irradiated fruits had a higher (
P ![](/images/entities/le.gif)
0.05) flavonoid content (naringinand narirutin) as compared to the freeze-dried pulp from the control fruits. Freeze-drying treatmentreduced (
P ![](/images/entities/le.gif)
0.05) the lycopene content, but the reduction (
P ![](/images/entities/le.gif)
0.05) in
![](/images/gifchars/beta2.gif)
-carotene content occurredonly in the control fruit. Reduction in
d-limonene and myrcene was observed in the irradiated fruitsat 6 days after harvest and in the freeze-dried samples. These results warrant testing of the effect ofpostharvest treatments and processing on bioactive compounds in functional systems as they havevaried effects on different bioactive compounds of grapefruit.Keywords:
Citrus paradisi; Rutaceae; grapefruit; irradiation; freeze drying; carotenoids; flavonoids;terpenoids