Pitaya is a non-climacteric fruit that has white or red flesh with numerous small, black seeds. It has a high moisture content; however, water loss during handling and storage negatively affects the fresh weight, firmness and appearance of the fruit, decreasing market value. Application of compatible postharvest coatings has been shown to benefit postharvest quality of many crops. The objective of this study was to evaluate the effect of two commercial coatings on weight loss and quality of pitaya during storage. Pitaya fruit were commercially harvested and sorted for uniformity of size and freedom from defects. Fruit were briefly immersed in either a vegetable oil-based coating (VOC; Sta-Fresh^® 2981) or a carnauba-based coating (CC; Endura-Fresh™ 6100) according to manufacturer’s recommendations. Fruit immersed in tap water served as a control. Fruit were fan-dried at room temperature for 20 min, then stored at 7 °C with 85% relative humidity (RH) and evaluated for selected physical quality parameters each 5 days during 20 days. After each evaluation, fruit were peeled and frozen for later analysis of soluble solids content (SSC), total titratable acidity (TTA); on day 15 fresh samples were evaluated by an untrained consumer sensory panel. CC prevented exocarp shriveling for 15 days of storage, compared to uncoated pitaya (16.3% area affected); shriveling in VOC was intermediate and not significantly different from the other treatments. Mesocarp firmness remained constant throughout 15 days of storage regardless of treatment. Fruit exocarp h* angle increased slightly by day 20, becoming slightly less red, and there were no negative treatment effects for the other quality factors measured: SSC (11.33%), TTA (0.25%), weight loss (5.5%) or sensory evaluations (appearance, flavor, texture, firmness, and juiciness). After 20 days storage, appearance for fruit from all treatments was rated unacceptable due to development of anthracnose lesions. It was concluded that both CC and VOC maintained quality of pitaya for 15 days at 7 °C and 85% RH by delaying exocarp shriveling.

The use of a robotic arm in agriculture is an immediate need to overcome labour shortage and dependence on foreign labour, especially in fruit harvesting and postharvest activities such as watermelon grading. The research was conducted to evaluate the effect of the fruit grading system using a robotic arm with a suction cup on fruit quality, such as general appearance (bruising, fungal infection on stem and fruit surface, and overall acceptability rating), endocarp colour and firmness, as well as composition data for watermelons stored at 25 °C for 28 days. All samples showed no signs of external and internal injuries up to 3 weeks. The incidence of fungal infection occurring at the tip of the stem was detected on the third week and it was not directly related to the use of the robotic arm. On the third week, the bruising symptoms were visible regardless of the treatment. There were no significant differences in watermelon endocarp colour and firmness, soluble solids content, total titratable acidity, ascorbic acid content, and moisture content. In conclusion, using a robotic arm with a suction cup during the watermelon grading process does not cause external and internal injury on the watermelon fruit. Abstrak: Penggunaan lengan robot dalam bidang pertanian merupakan keperluan terkini terutama dalam kerja penuaian produk buah-buahan serta aktiviti-aktiviti lepas tuai seperti penggredan buah tembikai dalam mengatasi masalah kekurangan tenaga buruh serta kebergantungan pada tenaga buruh asing. Kajian telah dijalankan untuk melihat kesan sistem pengendalian penggredan buah tembikai menggunakan lengan robot ke atas kecederaan luaran dan dalaman buah tembikai seperti skor luaran (jangkitan kulat di tangkai dan bahagian dalaman serta insiden lebam pada kulit), perubahan warna isi, ketegaran endokarpa dan data komposisi isi untuk tembikai yang disimpan selama 28 hari pada suhu 25 °C. Semua sampel buah tembikai menunjukkan tiada kesan kecederaan di bahagian luaran dan dalaman sehingga minggu ke-3.Insiden jangkitan kulat yang berlaku pada hujung tangkai dikesan pada minggu ketiga dan iaadalah tidak berkaitan dengan penggunaan lengan robotikKesan lebam juga dapat dilihat ketara pada minggu ke-3 tanpa mengira rawatan. Tiada perbezaan signifikan pada warna isi tembikai, ketegaran kulit, kandungan pepejal terlarut, jumlah keasidan tertitrat, kandungan asid askorbik dan kandungan kelembapan. Kesimpulannya, penggunaan lengan robot untuk diaplikasikan semasa aktiviti penggredan buah tembikai dengan suction cup tidak mendatangkan kesan kecederaan luaran dan dalaman ke atas buah tembikai.

In this research, a watermelon postharvest and process engineering system was designed, developed, and assessed its performance. The watermelon postharvest engineering system integrates a mechanised cleaning and a robotic sizing system with a capacity of 100-120 fruits/h, targeting fresh watermelon for the export market. The cleaning efficiency was 90%, whereas the sizing efficiency was 100%. Adding 250 ppm sodium dichloroisocyanurate in water during the cleaning process can extend the storage life of watermelon up to five weeks. The application of vacuum suction cups in the robotic sizing system did not cause any mechanical injury to the watermelon. The integration of mechanised cleaning (inclusive sanitation treatment) and robotic sizing systems is novel in Malaysia's watermelon postharvest engineering system. The system maintains good quality, reduces losses, and expands the market potential of watermelon. On the other hand, the watermelon mechanised puree processing system consists of a watermelon peeler, extractor, pasteuriser, and targeted watermelon puree production for small and medium enterprises (SMEs). Watermelon peeler, extractor and pasteuriser have a capacity of approximately 1 peeled watermelon/min, 430 kg watermelon puree/h, and up to 90 L watermelon puree/batch, respectively. The mechanised watermelon puree processing system showed the potential to diversify local agricultural products. The developed system can benefit fresh watermelon exporters and puree producers regarding market expansion.