A Brief Discussion on the Current State of Export of Taiwan's Pineapples

Peng,Tzu Chin（China Productivity Center Agricultural Innovation Department II）

Pineapples are an important export fruit for Taiwan. Since China's import ban, Japan became the key export market. However, there have been frequent quality issues with Taiwanese pineapples sold to Japan. Many instances of fruit browning have been reported. The fumigation and disinfection to control moths and scale insects detected upon arrival in the destination affect the prices and sale volumes of Taiwanese pineapples in Japan. Therefore, the stabilization of fruit quality is currently a crucial and urgent matter.

The main variety exported from Taiwan is the Tainong #17 Golden Diamond Pineapples, which have fine flesh, an edible core, and high water and sugar content. Although the fruit has a good flavor, it is prone to mold growth due to its high sugar-to-water ratio. A lack of robust quality control coupled with a lengthy shipping process can easily lead to quality deterioration of fruits.

In contrast, the MD2 variety has the highest global market share although its fibers are coarser and harder with less water content. Its core is less likely to brown during the marine transport in low temperatures. Therefore, the MD2 variety enjoys better export condition than the water and sugar-rich Taiwanese Golden Diamond pineapples and reports fewer mold and core browning issues.

According to the study conducted by researchers at the Taiwan Agricultural Research Institute (TARI), common problems with exported pineapples include:

Fruit acid-sugar ratio unstable; flavor not meeting expectations

Golden Diamond pineapples are famous for sweet flesh, but last year (2023) there were reports of high acidity. Researchers estimate that the deterioration of fruit quality was due to cold injury caused by a cold snap last year. Another reason was insufficient ripeness at harvest, resulting in sugar content not reaching 14°Brix.

Multiple Symptoms of Cold Injury

Pineapples thrive in the warm environment with abundant sunlight and well-distributed rainfall. Too low temperatures in winter is not conducive to pineapple growth. Pineapples are drought-tolerant but cannot withstand waterlogging. As a consequence of extreme climate due to global warming, Taiwanese pineapples were affected in 2023 by cold injury, in the form of localized water-soaking and internal browning.

Aging Appearance of Fruit

In addition to internal browning, Taiwanese pineapples sold in Japan also showed symptoms of rind browning and crown wilting. This may be due to direct shipment into 13°C containers for export without gradual cooling after harvest. The large temperature difference can easily cause fruit withering. Another possibility is the delayed distribution in the destination country and the resulting extended time lag from harvest to retail sale.

Simple Fumigation by the Destination Country or Pesticide Residue Issues

If Taiwanese pineapples are found to have scale insects or moths during random customs inspections upon arrival in the destination country, fumigation as a means of disinfection will be conducted. Generally speaking, minor fumigation (with phosphine gas) is applied if mealybugs are detected; major fumigation (with methyl bromide) is used if moths are identified.

According to official data in Japan, the fumigation rate for Taiwanese pineapples exported to Japan has reached as high as 30% during recent years. As fumigation is likely to damage the fruit quality, it affects the sales of Taiwanese pineapples.

To strengthen the quality of Taiwan’s exported pineapples, the research team within the Ministry of Agriculture have proposed several countermeasures and improvement methods outlined as follows:

Production Period and Yield Prediction

In February 2023, the Taiwan Agricultural Research Institute (TARI) under the Council of Agriculture (now the Ministry of Agriculture) of the Executive Yuan held a seminar on pineapple production and marketing techniques and introduced an innovative digital technology “Pineapple Field Management System” (i-PLANT). Kuan Ching-Shan, an associate researcher at the TARI’s Chiayi Branch, explained, "This system uses big data and cloud information to record crop production and farming operations via mobile devices. It features weather forecasts, production management, yield estimation, and sales & arrangement functions. Based on early warning and prediction results, it can adjust management techniques and post-harvest processing procedures.”

Harvesting, Sorting and Cleaning

According to the research by agricultural research and extension stations on harvesting and sorting, the harvesting of pineapples for export can be standardized in reference to maturity levels and color change charts. As post-harvest environmental temperature affects fruit ripening time, harvesting in different seasons should be based on different maturity levels, to ensure optimal ripeness when exported to and distributed in destination markets. Fruits should be selected based on the drumming sound, and poor-quality ones with abnormal appearances, severe damage, or pest and disease issues should be discarded.

Cleaning of fruits is also essential to reduce pests, larvae, dirt, and residues. Agricultural research units suggest the use of high-pressure water guns for cleaning. The crown must be intact during cleaning to avoid water from penetrating into the fruit. Ample sunlight can enhance cleaning effectiveness. To prevent secondary contamination, it is necessary to ensure zoning/segmenting, dust collection with equipment, and time-separated processing.

Pre-cooling operation

Researcher Chen Szu-Ju from the Kaohsiung District Agricultural Research and Extension Station emphasizes the importance of pre-cooling procedures for agricultural products entering the cold chain. The pineapple season is from March to May each year, with fruit temperatures reaching above 35°C when harvested in mid-April. However, the optimal storage and transportation temperature for Tainong #17 is 13°C. To improve the quality of exported pineapples on the shelve, a gradual cooling process is introduced, to allow the temperature-sensitive pineapples to adapt to lower temperatures gradually and hence maintain fruit appearance and flesh freshness.

Currently, room cooling and pressure cooling (forced-air cooling) are the mainstream pre-cooling methods. As room cooling takes longer to reduce temperature, pressure cooling can significantly improve pre-cooling efficiency. The Kaohsiung District Agricultural Research and Extension Station is currently exploring ways to help collection and packaging facilities implement efficient pre-cooling operations to maintain the fresh appearance of exported pineapples.

According to the Agricultural Statistics Query on the Ministry of Agriculture's website, Taiwan's pineapple export volume has been declining during the past three years (2021-2023), from 28,000 tons in 2021, to 20,000 tons in 2022, and further down to 16,000 tons in 2023. Although the exact reasons for such a decline are unclear, the recent instability in pineapple quality and the tarnished reputation of Taiwanese pineapples are undoubtedly one of the major factors. Therefore, it is imperative to improve the quality of Taiwan's exported pineapples.

In 2021, there were as many as 100 export companies for pineapples. By 2023, this number decreased to 59 companies, and the number of pineapple suppliers also dropped from 82 to 28. This indicates that the pineapple export supply chain is becoming increasingly concentrated, which is beneficial for scale and standardization of production methods.

Currently, agricultural research units have individually proposed improvement measures and standardized operating procedures from production, collection, and packaging to transportation. If the fruit quality can be successfully improved and an export supply chain can develop steadily by coordinating these procedures with suppliers and distributors and demo sites can be created from production, collection and packaging to transportation, it can serve as a paradigm for other exporters and collection and packaging facilities. This would have a significant effect on the quality enhancement Taiwan's exported pineapples.

Furthermore, Taiwan's export markets are mostly concentrated in Japan and Hong Kong. If a stable export supply chain can be established to improve fruit quality, it would also provide a substantial advantage in developing other new markets.