Effects of Myrtle (Myrtus communis L.) Fruit Cold Storage Under Modified Atmosphere on Liqueur Quality

Myrtle berries were stored for 30 days at 2C in air (control) or O2 at 60 or 80% with the aim to extend the liqueur processing season. Oxygen treated berries had a lower pH and titratable acidity than control. No treatment effect was observed on weight loss and respiration rate. CIELAB coordinates demonstrated a darkening of the oxygen treated fruit. Hydro-alcoholic extracts (HAE) from berries stored for 30 days at 80% O2 were less red colored than other treatments. After 10 and 20 days of storage, fruit held at 80% O2 had significantly higher total phenols than other treatments. Total anthocyanins increased with storage in all treatments. In the first 20 days of storage high oxygen treated berries showed higher anthocyanin content than control, whereas no difference among treatments were observedat 30 days. No differences were observed for the anthocyanin content in the HAE.