Fortune' mandarin oranges were coated with edible hydroxypropyl methylcellulose-lipid composite coatings. The coatings consisted of beeswax, carnauba wax, or shellac, at 2 lipid contents (20% and 60%). Weight loss of coated mandarins decreased significantly as lipid content increased. Beeswax (60%) emulsions were associated with the lowest weight loss. Coated fruit had higher internal CO 2 , lower internal O 2 , and higher ethanol contents than uncoated fruit. At 20% lipid content, internal O 2 was lower and ethanol content was higher than at 60% lipid content, which could be related to the low oxygen permeability of hydroxypropyl methylcellulose and the higher viscosity of these emulsions that could have affected final thickness.

Autumn Giant' plums were coated with edible hydroxypropyl methylcellulose-lipid composite coatings. The coatings consisted of beeswax or shellac, at 2 lipid content levels (20% and 60% dry basis). Weight loss of coated plums decreased as lipid content increased. No differences on weight loss were observed between uncoated and 20% lipid-coated plums, indicating that the natural waxes of plums are as effective as coatings having 20% lipid. Water-dipped plums experienced the highest weight loss. Fruit texture was not affected by coating after short-term storage at 20°C. However, for prolonged storage at 20°C, the coatings significantly reduced texture loss and internal breakdown compared to uncoated and water-dipped plums.

Citrus fruits are characterized by a complex mixture of volatiles making up their characteristic aromas, being the d-limonene the most abundant one. However, its role on citrus fruit and juice odor is controversial. Transgenic oranges engineered for alterations in the presence or concentration of few related chemical groups enable asking precise questions about their contribution to overall odor, either positive or negative, as perceived by the human nose. Here, either down- or up-regulation of a d-limonene synthase allowed us to infer that a decrease of as much as 51 times in d-limonene and an increase of as much as 3.2 times in linalool in juice were neutral for odor perception while an increase of only 3 times in ethyl esters stimulated the preference of 66% of the judges. The ability to address these questions presents exciting opportunities to understand the basic principles of selection of food.

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