Physical, chemical and sensory changes of cut apple (cv. Jonagored) stored in the dark at 4°C were evaluated. Colour was found to be the critical parameter for this product. Apple cubes underwent severe surface browning primarily during the initial days of storage. The shelf-life of cut apple was therefore very limited, to three days maximum.Sensory analyses and objective quality evaluations of cut apple were considered highly correlated in terms of colour and flavour, especially with respect to fructose and sucrose, showing that the selected sensory attributes were good indicators of overall fruit quality. .pt (A.M.M.B. Morais).

Purpose – The purpose of this paper is to evaluate waste at a Portuguese university setting in order to suggest improvements on foodservice sustainability. Design/methodology/approach – The work was developed during four weeks in order to allow the evaluation of parameters of an entire menu cycle. The index of waste/consumption (%) was obtained by the ratio between plate waste and the quantity of foods distributed, subtracting the weight of leftovers. Findings – The average index of waste/consumption was approximately 24 percent, higher in the days with a fish menu, values considered unacceptable. Each canteen user is served with approximately 940 g of foods, from which only 660 g were effectively consumed, corresponding to 80 g of leftovers and 200 g of waste. Originality/value – It seems possible and desirable to reduce food waste in order to optimize food unit profitability and sustainability. Reducing food waste will contribute to improve foodservice quality as well as consumer's satisfaction. Potential strategies to achieve this goal may include previous booking of meals, to adopt tray less during lunch and additionally analyze the eating patterns for a particular forecasted meal, and then prepare and serve food based on the appropriate forecast.

Polyphenoloxidase (PPO) was extracted from apple (cv. Jonagored) with addition of 2% PVP and 0.25% Triton X100 to the extraction buer containing phenolic adsorbents. Experiments were performed to evaluate the anity and speci®city towards several substrates. ÔJonagoredÕ apple PPO was found to have higher speci®city (lower K m) towards L-dopa, 4-methylcatechol and (+) catechin than other phenols tested, but the highest activity level was obtained with p-cresol. The ratio V max /K m indicates that p-cresol followed by L-dopa and 4-methylcatechol are the best substrates for ÔJonagoredÕ apple PPO. The enzyme activity showed two pH optima, at 5.0 and 7.5, at room temperature, with the main peak at pH 7.5 and the secondary one at pH 5.0 when catechol was the substrate.

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