Study 1.  Evaluation and characterization of postharvest behavior of eggplant 
              grown in identified areas 

Quality profile at the farm level

Quality evaluation was conducted in three major eggplant production sites namely Asingan, Pangasinan; Balete, Batangas; and San Antonio, Quezon. Quality classification based on farmers’ practice was first observed and then objective evaluation was made to assess and define the actual quality profile of eggplant at the farm level.

In all production sites, the harvested eggplants were commonly classified into good and reject based on external appearance. In some cases though, the produce is also classified by size, e.g. small, medium, long. In Quezon, another classification called semi-reject is adopted, to differentiate those fruits in-between the good quality and the reject. Table 1. shows the proportion based on the three classes. The percentage of good quality ranges from 62 to 80%, reject is from 19 to 50 % and the semi-reject amounts to around 19%. The major cause of rejection at the farm level is due to borer damage.

Further evaluation based on objective set of quality parameters, however revealed that only around 25% can be actually classified as good, and the remaining 75% have quality defects. Of the total defects, 79% is attributed to borer damage, 9% is deformed and 4% has disease. Minor forms of defects are due to sunscald, discoloration, immaturity and pitting (Table 2)

Quality profile at the market level

To assess the effect of handling, packaging and transport practices on the quality of eggplant, quality evaluation at the market level was also conducted. Samples were obtained from the two major markets in Metro Manila- the Divisoria and Balintawak markets. The eggplants actually originated from the production areas of Pangasinan and Nueva Ecija.

The result of quality evaluation of ‘Casino’ eggplant taken from Divisoria market is almost similar to the result of the farm level evaluation in Pangasinan, with 25/75 (in percent) ratio of good quality to those with quality defects. However, at the market level, the major type of quality defect was attributed to compression damage. Eggplant from Pangasinan exhibited 52.3% compression damage while those from Nueva Ecija had an average of 30%. In the latter, the magnitude of insect damage and bruises were also high amounting to 21.3% and third 16.3%, respectively (see Table 3).

Result of evaluation from Balintawak market shows relatively higher proportion of good quality and defective eggplant as compared to the data obtained from Divisoria. The ‘Casino’ eggplant which originated from Pangasinan has 35/65 ratio, while the round variety from Nueva Ecija has 80/20 ratio (see table 4). This data also indicates that the round variety is less prone to quality defects or damage. 

A simulated handling and transport trial was done to assess the market quality of eggplant coming from the production area in Quezon. The market distance simulated is relatively much shorter compared to the Manila market which usually is the destination of eggplant originating from the north. This could explain the difference in quality evaluation obtained from this trial.  More than 50% of the samples in both varieties- ‘Casino’ and ‘Bingo’ are considered as good quality. The other half are with quality defects and of this amount, compression damage consistently share the biggest percentage, averaging to more than 28%. Insect damage followed next, amounting to more than 10%, in both eggplant varieties (see table 5) 

Load–stress experiment

  Samples of ‘Casino’ eggplant from Asingan, Pangasinan were subjected to standard compression testing using Instron Universal Machine to determine its mechanical threshold. Results indicate that the critical load of eggplant for packaging, transport or handling range from 16.1 to 65.7 kg. This would mean that the weight of the eggplant that can be stacked up should not exceed these load range which is the critical  level at which the rupture occurs. 

          Other varieties will be tested also. 

Study 2. Shelf-life improvement of eggplant

Documentation of existing postharvest practices from the farm to the market

To determine the existing handling system and the postharvest handling practices on eggplant, interviews and actual field observation were conducted in the major eggplant production areas and market centers. The information that can be obtained from this activity will help identify critical areas in the handling system where improvement can be introduced. 

Practices at the farm

Harvesting and postharvest handling practices in the three production sites were almost similar. The time of harvest starts early in the morning, usually at 6:00 a.m. Harvesters picked the eggplant by pulling it from the stem using bare hands. In Pangasinan and Batangas, pickers carry collecting baskets on their backs where harvested fruit is placed while, in Quezon, they use sacks as collecting container. The harvested produce are then hauled and collected in a packingshed, but mostly the eggplants are damped on the soil without liners to protect them. The produce are then sorted out separating the good from those with quality defects such as insect and disease damage, over-mature and deformed or mishapened. After sorting, the fruits are packed in polyethylene bag (PEB) with 10, 20 or 33 kg capacity. The 20 kg capacity PEB is the most commonly used in all areas. In a farm in Quezon, washing of eggplant before packaging is done to clean the produce. The water though need to be changed more frequently. In Pangasinan and Batangas, the handlers use damp cloth to wipe away the dirt from the fruit. The packed eggplants are then loaded in trucks or in jeepneys for transport to the market. (See attached pictures)

Practices at the Market Centers 

Divisoria and Balintawak are the major wholesale markets where eggplants produced from the North ( Pangasinan, Tarlac, Nueva Ecija and Bulacan) down to the South ( Quezon, Bicol, Davao and Cebu) are brought usually by the viajeros plying all over the different production areas. Truckloads (300-500 bags) and jeepney loads (300 bags) of eggplant start arriving Divisoria at 7 p.m.. In  Balintawak, arrival starts as early as 10 a.m. in the morning with peak from 3 to 6 p.m. The stacking pile in the transport vehicle ranges from 8 bags (for jeeps) to 15 bags (for trucks) and the weight of each bag  ranges from 10 to 20 kg. 

Since both markets are wholesale markets, not much handling or repacking is done on the produce. Upon arrival at the market, the packed eggplant in PEB are unloaded immediately by the cargadors and these are brought to the buyers place either 
directly in the stalls within the market or in the buyer’s vehicle for transport to other markets. Some viajeros unload the eggplant on the market ground while waiting for the buyers to arrive.  The loading and unloading process still uses manual labor and dropping of the packages can be a major cause of damage to the produce.

Only those traders with permanent stalls in the market and who sell eggplant on both wholesale and retail, do some resorting or classification. Some of them repacked eggplant into smaller packs (from 20 kg to 10kg) and resort them by removing those with damage e.g. with cut, insect holes etc.  Fruits intended for retail are also either washed in water, sprinkled with water or wiped with a damped cloth to make it look cleaner, shiny and more  fresh.  Rejects are separated from the good quality and sold at half the regular price. The total amount of losses incurred by trader-retailers range from 10-40%, depending on the source and season. Much of these losses are due to insect damage.

Modified Atmosphere Packaging (MAP) studies

‘San Pedro’ eggplant from Batangas were kept under modified atmospheres by packing half kilogram fruits in polyethylene bags and stored at different temperatures (15°C, 20°C and ambient) for 9 days. Results showed that regardless of storage temperature, those under MAP had negligible shrivelling due to reduced weight loss. Control fruits  at ambient and 20°C had moderate shrivelling after 4 days storage. Those at 15°C were still slightly shrivelled up to 6 days and reached moderate shrivelling on  the 9th day.

Disease occurrence is one of the main limiting factors during storage of eggplants specially under MAP. In this study, ‘Casino’ eggplants from were disinfected with 100 and 200 ppm of commercial bleach prior to MAP. Disease incidence of control fruits and those washed in water only were higher than disinfected fruits (regardless of concentrations) after 7 days at ambient.

Study 3.  Ensuring food safety in eggplant

Determination of  safe levels of pesticide in eggplants

This activity will be done in collaboration with sub-project 3, the group from the National Crop Protection Center (NCPC). In addition to the washing (washing with plain water, and washing with plain water and soap) and cooking, the effect of storage on pesticide levels will also be monitored.

Data Generatation for product specification

Initial data on the size (length and diameter) shape  and weight of eggplant varieties  and various types of defects in the different production areas are still being monitored.

Table 1. Farmer’s quality classification of eggplant in various production sites

Classification	Production Area
	Pangasinan	Batangas	Quezon
Good	80.9	50.0	62.2
Semi –reject	-	-	18.9
Reject	19.1	-	18.9

Table 2. Quality Profile of Eggplant at the farm, Asingan, Pangasinan

Parameters	Kilo	Percent (%)
Good	11	24.4
With Defects	34	75.6
Insect damage     Diseased     Deformed     Sunscald      Immature      Discolored     Pitting	27.0   1.3   3.1   0.45   0.3   1.7   0.15	60.0  2.9  6.9  1.0  0.7  3.7  0.4

Table 3. Quality profile of eggplant, Casino var. from  Divisoria market

Parameters	Origin
	Nueva Ecija	Pangasinan
	Percent (%)
Good	22.6	27.0
With Defects	77.4	73.0
Bruised      Compressed     Cut/punctured     Shrivelled     Insect damage     Diseased	16.3 29.9   5.2   0 21.3   4.7	6.5 52.3   3.0   1.3   3.8   6.3

Table 4. Quality profile of eggplant from the Balintawak market

Parameters	Origin
	Nueva Ecija (Round var)	Pangasinan (Casino var)
Good	80.0	35.0
With Defects	20.0	65.0
Compressed/Bruised      Insect damage     Diseased	10.0 10.0   0	30.0 30.0   5.0

Table 5. Quality profile of eggplant, based on simulated transport from Quezon  to Los Baños

Parameters	‘Bingo’ var.	‘Casino’ var.
	Percent (%)
Good	51.4	53.6
With Defects	48.6	46.4
Insect damage      Compressed     Bruised      Cracks      Cut	10.4 28.0   7.9   1.8   0.5	12.2 29.8   3.1   0   1.3