IJERD – International Journal of Environmental and Rural Development (2022) 13-2

Research article
erd

Proposal of New Pickles to Improve Food Sanitation at
Wet Markets in Cambodia
SOKLY SORM
Graduate School of Agriculture, Tokyo University of Agriculture, Tokyo, JapanYOSHIKI MURAMATSU*
Tokyo University of Agriculture, Tokyo, Japan
Email: y-murama@nodai.ac.jp

DAIKI OKATokyo University of Agriculture, Tokyo, JapanYURI TANIOKA
Tokyo University of Agriculture, Tokyo, Japan

MASATAKA UCHINOTokyo University of Agriculture, Tokyo, JapanSHUKI MURAMATSU
Showa Women’s University, Tokyo, Japan

MOTOE SEKIDO
Yamanashi Gakuin Junior College, Yamanashi, Japan

TAKAHIKO NAKAMURATokyo University of Agriculture, Tokyo, JapanTORU NAKAJIMATokyo University of Agriculture, Tokyo, JapanEIICHIRO SAKAGUCHITokyo University of Agriculture, Tokyo, JapanSHOTARO KAWAKAMITokyo University of Agriculture, Tokyo, JapanMARI ARIMITSU
Institute of Environmental Rehabilitation and Conservation, Tokyo, Japan

MACHITO MIHARATokyo University of Agriculture, Tokyo, Japan
Received 20 January 2022

Accepted 13 June 2022(*Corresponding Author)

Abstract The lack of heat treatment is one possible factor leading to highly contaminatedpickles with microbes, including the bacteria that cause food poisoning. A heating processthat sterilizes food products is effective in reducing the microbial content of pickles. We
applied heat treatments to ensure that homemade pickles were safe to consume. In thisstudy, 2 kinds of pickled young papaya were made to develop a new, safe processed foodthat effectively utilizes agricultural products. The objective was to evaluate the possibilityof acceptance of these samples in Cambodia and other Asian countries. The sensory
evaluation indicated that the samples were acceptable but still need further improvement.

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Keywords young papaya, pickle, heat treatment, sensory evaluation, acceptability

INTRODUCTION
Pickles are a popular ready-to-eat food, and most pickles are produced in traditional ways in
Cambodia. Pickles are easy to make, and do not require for any special equipment or skills. The
basic procedure for making pickles is to wash the vegetables and then add sugar, salt, and otheringredients such as fish sauce, soy sauce, garlic, chili, and rice. Most pickles are stored in jars andplaced in the sun or in a room at ambient temperature for 1 to 4 days. Pickles are commonly sold in
wet markets in Cambodia. Almost all pickles sold in the wet markets are made without any heatingprocess. Furthermore, the pickled product is displayed in a wet market under poor storage
conditions; for example, there is no temperature control and no packaging. The hygiene practices ofthe local wet markets are very poor, which has subsequently led to food contamination. Thissituation is risky, and food poisoning incidents are often associated with these pickled products(Anal et al., 2019). Chrun et al. (2017) also pointed out the poor hygiene at the local wet markets in
Cambodia and the necessity of identifying the source of contamination. According to reports by
Muramatsu et al. (2020a, 2020b), the pickles sold at the wet markets in Cambodia are highly
contaminated with microbes, including bacteria that cause food poisoning. In addition, theinspection of wet markets showed that the pickle products were not handled in a hygienic manner.
It is necessary for food handlers to receive practical knowledge on food hygiene to prevent the
spread of bacterial food contamination. This contamination could be caused by a manufacturing
process that does not use heat treatment. Pasteurization destroys pathogenic microorganisms incertain foods and beverages. A new pickling method that adds heat treatment to the production
process is needed to reduce the risk of food poisoning posted by pickled products. Adding apasteurization procedure to the production process can improve food safety and/or food sanitation(Breidt et al., 2004). A heating process that pasteurizes foods to reduce food spoilage microbes canbe applied to many kinds of food products.
We conducted a survey of Cambodians in their twenties and thirties regarding pickles via the
Messenger App and received 30 responses. Some respondents mentioned that they enjoy eating
pickles on a daily basis but that consuming pickles causes them to vomit, experience diarrhea andbloat, and have headaches. The majority of respondents suggested that pickles should be made in asafe and high-quality manner, including packaging. The necessity of improving and guaranteeing
food sanitation and safety were also recognized in this survey.
In Cambodia, papaya is an important agricultural product and an existing resource that is easy
to grow and maintain. People can grow papaya in their homes or on a large scale in all areas of thecountry. People grow papaya as their livelihood, they consume it, and they sell it fresh in wet
market (MAFF/GDA, 2010). Papaya can be harvested and is available year-round. A small amountof mature papaya (which is light yellow in color) is often pickled, but young fresh papaya is not
pickled. Young fresh papaya or young papaya is unripe papaya before it ripens to yellow. Youngpapaya is also called "green papaya". The colors of the pericarp and the flesh of fruit of young
papaya are green and white, respectively.
In this study, 2 kinds of pickled young papaya were developed to test a new, safe, processed
food. These pickles are kinds of quick pickles and are not fermented pickles. This study aimed tofind the new usage of young papaya to develop microbiologically safe pickles. We examined thepossibility of acceptance of these samples in Cambodian and Asian markets. Heat treatment wasadded to the production process. The pickles were packed in a glass bottle, which is easy topasteurize and enhances product value, quality, and safety. Glass bottles are readily accessible in
Cambodia at a reasonable price and can be reused. Fresh young papayas are also reasonably priced
and easy to find in Cambodia.
OBJECTIVE
The objectives of this study were 1) to develop pickled young papaya processed with heat
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treatment and 2) to evaluate the possibility of acceptance of the pickles that ensure food sanitationin Cambodian and Asian markets.
METHODOLOGY
Materials and Pickle Production Process
Young papaya (Carica papaya) imported from Thailand were purchased at a supermarket in Tokyo,
Japan. Before testing, the young papayas were stored in a refrigerator at approximately 4°C.
To develop the composition of seasoning, we first processed 3 kinds of pickles based on abook of Japanese recipes and Cambodian homemade recipes. These pickles were evaluated by 8
Cambodians in Phnom Penh, Cambodia. Based on the evaluation results and comments from thepanelists, we revised and decided on 2 types of seasoning: sour pickles and salty pickles. Table 1
shows the seasonings used to make the 2 types of pickled young papayas. The green pepper inTable 1 was a fresh green pepper (Piper nigrum). The compositions of the pickles processed in thisstudy are presented in Table 2.
Table 1 Seasonings used to make the 2 types of samples
SampleSeasoning

Sour
115
12
300
200
20
-

Sugar (g)Salt (g)Vinegar (ml)Water (ml)Soy sauce (ml)Fish sauce (ml)Green pepper (piece)
Chili (piece)

Salty
110
25
190
190
11
59
1

*6-8 pieces of young papaya (about 30-40 cm3)

Table 2 Compositions of the 2 types of pickled young papayas
Component (%)
Moisture
Proteinfat
Ash
Carbohydrates(Sugar)(Dietary fiber)
Salt equivalent

SampleSour taste
81.2
0.6
0
1.4
16.8
(13.6)(3.2)
1.1

Salty taste
73.5
1.4
0
5.0
20.1
(17.2)(2.9)
4.6

Fig. 1 shows the production process for the 2 types of pickles. After the peel was removed
from the young papaya, it was cut into a rectangular parallelepiped (10 mm in depth and width, and
50 mm in height) using a knife. The liquid seasoning was heated to boiling, and the spice and 6-8
pieces of young papaya were placed into a glass bottle up to 3-5 mm from the bottle lid. After
closing the lid of the bottle (sealing), the bottle was turned upside down. The hot glass bottle filledwith seasoning and young papaya was submerged in hot water at a temperature of 70°C. The hotwater was heated to boiling. After coming to a boil, the glass bottle was maintained in boilingwater for 10 minutes to raise the center temperature above 75°C. After this pasteurization, the glass
bottle was cooled at room temperature (approximately 25°C) in the inverted state. The
pasteurization conditions and methods adopted in this study conformed to the regulations for
enforcement of the food sanitation act in Japan. The pickles were then stored at room temperaturefor 4 days. The pH values of the liquid seasonings were 3.60 for the sour pickles and 3.35 for theⒸ ISERD

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salty pickles. Fig. 2 shows photographs of the sour and salty samples. The appearances of the sourand salty samples were light and dark yellow, respectively. The heating treatments, i.e., the heatingof the liquid seasoning, the hot packing, and the pasteurization were important additions to the
production process to improve and/or maintain food sanitation.

Fig. 1 Production process for the 2 types of pickled young papayas: sour and salty

Fig. 2 The appearance of sour and salty pickles
Sensory Evaluation of Pickled Young Papaya
The color, sweetness, sourness, saltiness, flavor, texture, and overall evaluation of each sample
were quantified using a five-point hedonic scale (1: strongly dislike, 2: dislike, 3: neutral, 4: like,and 5: strongly like) for the sensory test (preference type). The sensory evaluations were conductedin Japan (Setagaya) and in Cambodia (Phnom Penh). Table 3 presents the panelist demographics.
The total number of panelists was 32, and the nationality of all panelists was Asian. The panelists“Cambodia-1” evaluated only the sour sample in Cambodia; otherwise, the panelists evaluated both
samples in Japan. The panelists were divided into 2 panels: Cambodian and non-Cambodian for thestatistical analysis of the sensory evaluation results. The sour and salty samples were tested by 15
Cambodian panelists and 17 non-Cambodian panelists (total, 32 panelists) and 7 Cambodian
panelists and 17 non-Cambodian panelists (total, 24 panelists), respectively.
Table 3 Panelist demographics for the sensory evaluation of the samples
Nationality
Cambodia-1a
Cambodia-2b
Vietnam b
Thailand b
Myanmar b
Philippines b
Indonesia b
Sri Lanka b

Number
8
7
5
4
3
2
2
1

Age (Average)
21-35 (28)23-38 (27)20-24 (22)23-38 (29)22-25 (24)29, 3024, 3626

a: These panelists evaluated only the sour taste sample in Cambodia.
b: These panelists evaluated both samples in Japan.

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RESULTS AND DISCUSSION
Fig. 3(a) shows the sensory evaluation results for the sour sample. The results for the Cambodian
panel in Fig. 3(a) include the panelists “Cambodia-1” and “Cambodia-2” shown in Table 3. The
average scores of the sensory evaluation characteristics of the sour sample ranged from 3.3-3.7 for
Cambodians and 3.6-3.9 for non-Cambodians. The overall evaluation shows whether the pickled
product was judged overall to be acceptable or not acceptable. The average overall evaluation wasscored 3.5 by Cambodians and 3.9 by the non-Cambodian panelists. The non-Cambodian panel
gave higher scores than the Cambodian panel, and the sour sample was more preferred by nonCambodians than by Cambodians. The average values of each evaluation characteristic for the sour
sample were tested for differences (t test) between the Cambodian and the non-Cambodian panels,
and there were no significant differences (at the 5% significance level) for any characteristics,
except for the overall evaluation. The overall evaluation score of the non-Cambodian panel was
significantly higher, and this result showed the high acceptability of the sour sample by the nonCambodian panel. These results indicate that the sour sample was acceptable by Cambodians andother Asians because the overall evaluation scores for both panels were over 3.0. In addition, the ttest for each characteristic and for the average value between the panelists of "Cambodia-1" and"Cambodia-2" (Table 3) showed no significant differences. This result suggests that the evaluation
results obtained in Japan could be applied to evaluate the acceptability of the samples in Cambodia.
Most panelists evaluated the texture as adequate but not firm. Some Cambodian panelists
commented that the sweetness was adequate, and if the sourness and saltiness were reduced slightly
in the sour sample, the evaluation of this sample would increase. In contrast, some non-Cambodian
panelists stated that the sourness was adequate, and increasing the sweetness and saltiness slightly
might improve the score.
The sensory evaluation of the salty sample is presented in Fig. 3(b). The average scores for thesalty sample were 2.6-3.9 for Cambodians and 2.9-4.3 for non-Cambodians. The t test showed nosignificant differences in the average values for each characteristic between the Cambodian and thenon-Cambodian panels. Except for the texture, the non-Cambodian panelists assigned higher scoresthan the Cambodian panelists on all characteristics. The average values for color were nearly 4.0,
and the color of the salty sample was favored by both panels. Although the average values ofsaltiness for the Cambodian and the non-Cambodian panels and sweetness for the Cambodian panel
did not exceed 3.0, the overall evaluation scores were 3.1 for the Cambodian panel and 3.4 for the
non-Cambodian panel.

The symbol (*) means a significant difference (p < 0.05)

Fig. 3 Comparison of sensory evaluation of pickled young papaya between Cambodianand non-Cambodian panels (a) sour sample; (b) salty samples
The panelists commented that the dark yellow color of the salty sample was attractive andlooked delicious, but the texture was soft, and a crunchier texture might change the evaluation.
Most Cambodian panelists indicated that the taste of the salty sample was salty and lackedⒸ ISERD

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sweetness. Although there are opportunities for improvement regarding the taste and the texture of
the salty sample, i.e., lowering the salt content, increasing the sweetness, and increasing the
crunchiness, the acceptability of the salty sample was indicated by the overall evaluation scores(over 3.0).
To improve food sanitation, heat treatments were added to the production process of the sourand salty samples. These samples received mostly favorable evaluations from Cambodian andAsian panelists. The heat treatments and the preservation period also affected the texture of the
pickles. Therefore, it would be useful to investigate the relationships between these factors. Further
studies will require more panelists to analyze the evaluation of pickles in detail and to assess theiracceptability. We will optimize the process to produce safe, high quality, and more acceptable
pickles.
CONCLUSION
Young papaya was used to develop a new pickle product in this study. The heat treatments, i.e., theheating of liquid seasoning, a hot pack, and pasteurization were added to the production process toimprove and guarantee food safety. Two types of young papaya pickles, the sour and salty, weremade and evaluated by Cambodians and Asians in Cambodia and Japan. The color, sweetness,sourness, saltiness, flavor, texture, and overall evaluation of each sample were quantified using afive-point hedonic scale (1: strongly dislike, 2: dislike, 3: neutral, 4: like, and 5: strongly like) for
the sensory test (preference type). The sensory evaluation indicated that the samples wereconsidered to be acceptable but needed further improvement. Because both pickles received mostly
favorable evaluations from Cambodian and Asian panelists based on the overall evaluation scores(over 3.0), both pickles were potentially acceptable as new processed foods in Cambodia and inother Asian countries. This finding will be useful for food preservation, reducing postharvest losses,
providing jobs for domestic Khmer people (particularly women), and increasing the income of
citizens as well as the Cambodian nation.
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