Effect Of Structure And Type Of Produce On Respira.docx

Effect of structure and type of produce on respiration rate. Shonnia Simin (188998)

Department of Food Technology, Faculty of Food Science and Technoogy, University Putra Malaysia, 43400 Serdang, Selangor, Malaysia.

Abstract: The main objective of the present study was to determine the respiration rate based on different structure and type of produce. The samples were cut in a cube size and placed into a closed jar for 2 hours. The respiration rate of the samples were determined based on the observation of the water droplets that present in the closed jar. From the observation, mung sprout beans, long beans and broccoli were classified as high respiration rate. Carrot and cabbage were classified as medium respiration rate while sweet potato classified as low respiration rate. Overall, respiration rate was found as one of the important measurements and consideration in reducing post-harvest loss.

Hence, proper control measurements

should be studied in order to slow down the aging process and reduce post-harvest loss.

Keywords: Respiration rate, post harvest, water droplets, observation.

Introduction

Post-harvest technology are usually focusing on the loss reduction and quality optimization especially during the fresh fruits and vegetables post-harvest chain. Hence, there are several control measures are taken to prevent undesirable changes to the fresh produce. In order to maximize the post-harvest control, there are few factors that needed to taken care in order to prevent post-harvest losses. These include the varieties or types of produces, post-harvest operation (storage, transport and marketing) and also the physical changes of produces due to respiration and ripening.

Materials and Methods

Materials and Apparatus Bean sprout, long beans, broccoli, carrot, cabbage and sweet potatoes were obtained from a local supermarket (Selangor, Malaysia). Apparatus used were chopping board, knife, plastic jar with cap and weight balance. Methods The samples were cut into cube size (2cm x 2cm) or 2cm long. They were then weighed for 100g and placed into a closed jar. All the samples were prepared in triplicate. The samples were observed after 2 hours, the respiration rate of each samples were determined by their amount of released of water vapour.

Results and Discussion

Table 1. Respiration rate of each type of produces. Type of produce

Respiration rate

Mung bean sprouts

High

Long beans

High

Broccoli

High

Carrot

Medium

Cabbage

Medium

Sweet potato

Low

The respiration rate of each type of produces is provided in Table 1. Respiration rate was determined by observation on the produce’s formation of water droplets in jar. This is because during respiration process, produce consumed oxygen and the carbohydrates stored will break down which release water, carbon dioxide and energy. Therefore, for high respiration rate, high amount of water droplets were observed in the closed jar. Thus, different type of produces has different respiration rate and this is an important consideration in optimizing post-harvest quality.

According to Food and Agriculture Organization (FAO), respiration rate can be influenced by the type of produce. This can be explained as vegetables consists of great diversity plant organs (roots, tubers,seeds,flowers, leaves,stems and sprouts) which all of them have different metabolic activities, thus, different respiration rates (Fonseca et al. 2002). Surface area ratio of the produce also one of the factors that cause different respiration rate,. The greater the surface area, the faster the water loss. Moreover, the high amount of pores on the surface on the produce also contribute to the high respiration rate. For example, sweet potato which has a thick skin with few pores has a low respiration rate (FAO, n.d). Respiration process in fresh produce often link to the post-harvest loss due to the deterioration of produces’ quality (Mangal and Dhyani, 2013). If respiration process happened too fast, the aging process will be faster, this will affect the storage time period of the produce. Hence, in order to prolong the shelf life of the produces, modified atmosphere packaging (MAP) design is applied. The modified atmosphere condition can control the timing of climacteric rise by delaying as stated in a study conducted by Young, Romani and Biale (1962). Other than that, the most important external factor is temperature. In an optimum temperature, enzymes are in the best condition which increase the respiration rate. At high temperature, denaturation of enzymes will occur and reduce respiration rates while at lower temperature, respiration rate will slower but if it is too low, will cause injury cause in higher respiration rate.

Conclusion

In conclusion, different types (plant organ) of produce will have different respiration rate due to different metabolic activity, surface area ratio and amount of pores. Respiration rate plays an important measurement that affect the post-harvest loss. Hence, proper control measurements should be studied in order to slow down the aging process and reduce post-harvest loss.

References