Trends in maintaining postharvest freshness and quality of Rubus berries

Blackberries and raspberries, commonly known as Rubus berries, are commercially grown worldwide across different climates. Rubus berries contain wide array of phytochemicals, vitamins, dietary fibers, minerals, and unsaturated fatty acids. Nevertheless, these berries have short storage life which is the major constraint in their supply chains leading to higher postharvest losses. Inappropriate harvest handling, physical bruising, insect pests, and postharvest diseases lower the acceptability of fruit among consumers and other supply chain stakeholders. Additionally, the susceptibility to microbial decay, fruit softening, higher ethylene production, respiratory activity, and increased oxidation of anthocyanins, phenolics, and flavonoids considerably affects the marketability of Rubus berries at domestic and international markets. To date, several postharvest strategies such as cold storage, precooling, modified and controlled atmospheres, anti-ripening chemicals, edible coatings, biological agents, and nonchemical alternatives (heat treatment, ultrasound, irradiations, ozone) have been reported to prolong storage life, ensure food safety, and maintain the nutritional quality of Rubus berries. This review briefly encompasses multiple aspects including harvest maturity indices, regulation of fruit ripening, pre and postharvest factors affecting fruit quality, and an update on postharvest quality preservation by employing postharvest technologies to extend the storage life and maintaining the bioactive compounds in Rubus berries which are lacking in the literature. Accordingly, this review provides valuable information to the industry stakeholders and scientists offering relevant solutions, limitations in the application of certain technologies at commercial scale, highlighting research gaps, and paving the way forward for future investigations.