Non-enzymatic browning in single-strength reconstituted citrus juice in TetraBrik cartons

In freshly produced commercial citrus juice, aseptically filled in a TetraBrik carton, it has been demonstrated that non‐enzymatic browning was mainly due to carbonyl compounds formed from l‐ascorbic acid degradation. At different storage temperatures (4−37 °C), this, browning showed first‐order kinetics with higher rate constants as temperature was increased. An assessment of the degree of browning as a function of time in the presence of additives (sodium metabisulfite, sodium tripolyphosphate, (carboxymethyl)cellulose and sorbitol) showed that the addition of sodium metabisulfite substantially reduced browning, particularly at the higher storage temperatures of 76 and 105 °C where a greater accumulation of 5‐(hydroxymethyl)furfuraldehyde was observed.