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Water recyling in fruit and vegetable processing may contribute to decreasing industrial waste and load. Water was recycled for washing orange peel to prepare a high dietary fibre powder using tap water washing as the standard. Total sugar (12.1–13.1%), total dietary fibre (70–71.5%), soluble dietary fibre (21–22%), yield (59–60%), water holding capacity (7.8–8.1 g water g−1 dry matter), colour and microbiological quality of a dry product were not significantly affected when the liquors from pulping and pressing were recycled for washing peel. Recycling liquors from pulping and pressing gave the highest energy (43%) and water (33.4%) savings, respectively.

: Seasonal changes in composition and properties of a high dietary Ðbre product from grapefruit peel were studied. Total dietary Ðbre decreased in January as compared to September (586È686 g kg~1). Main constituents from soluble Ðbre were : uronic acids (172È233 g kg~1), arabinose (13È41 g kg~1), galactose (4È11 g kg~1), glucose (5È10 g kg~1) and xylose (2È3 g kg~1). Insoluble dietary Ðbre (385È392 g kg~1) did not signiÐcantly change during the season. Its main constituents were : Klason lignin (29È37 g kg~1), uronic acids (33È 70 g kg~1) and neutral sugars : glucose (149È196 g kg~1), mannose (45È 50 g kg~1), xylose (25È38 g kg~1), galactose (20È22 g kg~1) and arabinose (16È45 g kg~1). Total neutral sugars from dietary Ðbre decreased over the harvest period (315È383 g kg~1) and an inverse trend was observed in total freesugars from samples (49È85 g kg~1). Both, water holding capacity (7É0È9É3 g water g~1 dry sample) and glucose retardation index (7É0È25É3%) decreased from early stages in fruit development until late in the harvest season. Seasonal changes in grapefruit peel should be taken into account, in order to standardise the quality of rich Ðbre products.