Resumen

MONICO PIFARRE, Amalia et al. Acceptability and nutritional quality of a beverage based on orange juice and whey powder, preserved by heat or high-intensity pulsed electric fields (HIPEF).. ALAN [online]. 2006, vol.56, n.4, pp.356-360. ISSN 0004-0622.

Orange juice may be a nutrient vehicle that helps to improve diet quality. The addition of whey allows the incorporation of high quality proteins. However, a good acceptability is necessary. The aims of the present study were: a) to assess the acceptability of a beverage prepared with orange juice (J) and whey powder (WP) at 7 g/100 g (J+WP7) or at 13g/100 g (J+WP13); b) to measure available lysine content and ascorbic acid retention of the more accepted formulation, comparing the effect of HIPEF treatment (29 kV/cm, tacum: 59ìs) with a conventional heat treatment at 75°C, for 15 minutes (HT). The beverages were subjected to sensory evaluation (Friedman test). Available lysine was assessed by the Carpenter method, modified by Booth, and vitamin C by HPLC; minerals Na and K, by flame photometry; Ca, Mg and Zn by atomic absorption spectrometry. There were no significant differences between the acceptance of J and J+WP7. J+WP13 was significantly less accepted (p<0.01), so it was discarded. Available lysine (mg/g protein) in untreated J+WP7 was 60.2±0.15; after treatments: 50.0±2.8 (HT) and 51.0±3.4 (HIPEF). The HIPEF treated J and (J+WP7) retained 100% and 98% of their vitamin C initial content and the HT treated, 91% and 88%, respectively. The amount of whey powder added to the orange juice conditioned the acceptability. The juice containing 7% of whey powder was well accepted, and after treatment by HIPEF, it retained a good nutritional quality, regarding available lysine, vitamin C retention and provision of mineral nutrients.

Palabras clave : Enriched juice; high-intensity pulsed electric fields; available lysine; vitamin C; minerals.