Abstract
Approximately one third of the food produced globally is lost or wasted along the supply chain. Reducing this would be an important measure to increase the global food supply as the world continues the struggle to feed its people sustainably. Not merely a waste of food, these losses also represent a waste of human effort and agricultural inputs from expensive fertilizers to natural resources as well as contributing to global greenhouse gas emissions. Measuring the extent of, and understanding the reasons for, these losses can assist in developing appropriate measures required to prevent or reduce such losses. Therefore, the objective of this research was to quantify postharvest losses in quantity and quality of 'Packham's Triumph' pears at farm and simulated retail levels. Pears were sampled from two farms in the Western Cape Province of South Africa, the largest deciduous fruit production and export region in Southern Africa. The greatest losses measured along the supply chain were on-farm immediately after harvest, with 18% recorded. The main reasons for on-farm losses were small size (65%), deformity (26%), and chafed peel (9%). After 14 days in cold storage (-0.3 +/- 0.7 degrees C, 81.3 +/- 4.1% RH), mean pear losses were 0.86% which increased to 1.49% after 28 days. After 10 days of further storage under simulated market conditions (5.4 +/- 0.6 degrees C, 83.7 +/- 2.9% RH), fruit losses were 1.52% during retail marketing and 2.09% during export. Storing pears under ambient conditions (25.1 +/- 1.3 degrees C and 46.6 +/- 6.0% RH) resulted in a higher incidence of losses, increasing from 0.90 to 1.55 and 2.25% after 3, 7, and 10 days, respectively. The socio-economic impacts of these postharvest losses amounted to financial losses of between ZAR 492 million (USD 34.1 million according to the conversion rate of 14 April 2021) to over ZAR 831 million annually, and this was associated with the loss of 301 million MJ of fossil energy, 69 million m(3) of fresh water and contributed to the emission of approximately 19,690 tons of CO2 equivalent. The fresh water lost could sustain 3.7 million individuals daily for a whole year at a daily minimum usage rate of 0.05 m(3) per day while it will require planting 0.5 million trees to sink the 19,690 tons GHG emissions of the pear losses (0.039 metric ton per urban tree planted). Decreasing postharvest losses will conserve resources as well as improve food security and nutrition, objectives of the post-2015 sustainable development agenda led by the United Nations.