Processing factors affecting the osmotic dehydration of diced green peppers

A 25–2 fractional factorial design was used to investigate the effect of salt (2–10%), sorbitol (0–10%) concentration, agitation (0–80 r.p.m.), tissue to solution ratio (1:3 to 1:6) and temperature (20–50 °C) on weight loss, solids gain, salt and sorbitol uptake, water activity, tissue brix and solution brix, during osmotic dehydration (OD) of diced green peppers. Results showed that salt and sorbitol concentration were the most significant factors. In the first half hour of the osmotic process, salt and sorbitol significantly increased weight loss, solids gain and tissue brix, and decreased water activity. Temperature was also a significant factor. It increased weight loss during the first 2 h of the process, and decreased water activity after 20 h of osmosis. Agitation and tissue to solution ratio were less important.