Table 3. Quality parameters of onion shreds dried at different temperatures in heat pump drier.

Drying air temperature °C	DR	RR	ΔE	b(pyruvic acid) µmol/g	w(ascorbic acid) mg/100 g
35	5.07±0.52	4.32±0.35	10.25±0.65	46.48±0.82	17.26±0.48
40	5.28±0.35	4.71±0.38	09.84±0.42	51.43±0.58	19.84±0.59
45	6.05±0.42	5.03±0.46	10.03±0.55	57.12±0.76	22.41±0.78
50	6.79±0.63	5.18±0.56	10.21±0.32	56.23±0.49	22.30±0.53

DR=dehydration ratio, RR=rehydration ratio, ΔE=colour difference