Processing and preservation of fruits (pineapple, banana, papaya) in Madhupur Region

Bangladesh produces huge amounts of fruit and vegetable annually. Madhupur region is well known for Pineapple production as well as other fruits like banana, papaya etc. Most fruits and vegetables are highly perishable, spoilage after harvest is also a significant issue; in Bangladesh, losses could range from 24 to 44%, according to Hassan (2010). If these perishables are processed in to shelf stable products, like dried item, flakes, chips etc. the financial return will be expected by the growers as well as post-harvest loss of the commodities will be reduced to a greater extent.

• Rural poor farmer in Madhupur region adopted practiced capacity development fruit product technologies using low-cost locally fabricated food processing equipment. • Skill up by the practical training for poor farmer specially aboriginal (Garo, Barman, coach) farmer on fruit processing, preservation and reduce the pre- and post-harvest losses.

If fruits products are processed into shelf-stable products, the production and the financial return will be increased by the growers as well as post harvest losses will be reduced to a greater extent.

The pineapple, Papaya and bananas were purchased from the local market of Madhupur, Bangladesh. Pineapple and bananas were made into self-stable osmotically dehydrated air fried chips, whereas osmotically dehydrated green papaya flakes were produced from green papaya. The fruits were peeled, washed then manually cut with sharp stainless-steel knife into three catagory shapes as 2mm, 4mm and 6 mm for pineapple and banana chips, whereas papaya slices were cut into 4mm, 6mm and 8 mm thickness. All the pineapple and banana slices were dipped into three particular bowls for Osmotic dehydration (20%, 30% and 40% sugar). 30%, 40% and 50% osmotic sugar solutions were used for papaya flakes. The kinetics of heat and mass transfer behavior were identified and nutritional and sensory evaluation were made.

The current work was carried out to prepare osmotic dehydrated air fried pineapple chips. 30% sugar solution possed the best results for sensory attributes. Three different thickness of pineapple slices (2mm, 4mm, 6mm) were subjected to 30% sugar osmotic solution, dried and then fried with three different temperature (100℃, 110℃, 120℃) in air fryer. The frying time inserted more influence on color change. It was shown that protein content, vitamin C and pH level decreased with increasing the temperature. On the other hand ash, fat, and crude fiber increased with the increase of temperature due to it’s own physicochemical properties. The rate of frying depends on air temperature and thickness of product thickness. Frying time to a specific moisture ratio increased with a increase of sample thickness. While the rate constant has a power law relationship with thickness and the value of index of equation was quite below 2 indicating the presence of significant external resistant to mass transfer and increasing in higher frying rate. Activation energy was found higher in 2mm thickness (9.015 kcal/mole). In this experiment, also used two type of packaging material (HDPE and PET) to determine the changes of chips physicochemical properties like vitamin C, pH and color. Vitamin C and pH reduces lower in HDPE than PET. Organoleptic properties (color, flavor, crispiness and overall acceptability) were determined and all the parameters were satisfied by panelists. The colorparameters (L*, a*, b*) were seemed to be significantly different from 0 day to 21 days of storage and it was found that these parameters had been more stable in HDPE packaging than in PET. It was observed that % of osmotic solution and thickness effect on the different properties of papaya flakes. During osmosis, 50% with 8 mm thickened sample gave the highest value of % water loss and % solid gain. Drying rate and vitamin C content follow the first order kinetics to time of storage. During storage of 21 days the physicochemical properties decreased to some extent at room temperature. L* value decreased, a* increased and b* value decreased in all sample during storage. The best quality of osmotic dehydrated papaya flakes was found in HDPE.

Value added air fried osmotic dehydrated pineapple chips (30%) was developed. Air frying kinetics parameters were identified. It was seen the temperature dependent Arhenius type reaction was followed. HDPE showed the best results in terms of vitamin C retention and moisture loss. Osmotically dehydrated pineapple flakes (50%) were produced. An exponential relationship was found to the drying rate constant and slice thickness of dehydrated papaya flakes. HDPE packaging material showed the best results for papaya flakes during a short storage period of 21 days. Vitamin-C degradation of papaya flakes during storage at room temperature followed the first order kinetics.