Investigating of oppurtunuties for production of durable and value-added products from watermelons with low possibility of marketability to be used in animal nutrition

In this project, it was aimed to produce value-added and durable watermelon products from the shell, seeds and pulp of the watermelons that were unmarketed due to excess demand in the marketplace. 3 different products named as watermelon puree, watermelon juice, and watermelon pulp were produced from 3 different watermelon variety that were harvested 15 days ago. No treatment was applied to one of those product groups, one group were called as fresh products, one group called as non-acidified group were exposed to pressure-heating, and the other group called as acidified group were exposed to pressure heating+citric acid. The project has been designed in three works. Physical, chemical, microbiological, miycotoxin analysis were conducted on samples taken from fresh products and immediately after canning (study I), on days of 0, 30, 90, 180 of the storage period (study II), and, after 0, 2 and 4 days of opening the cans (study III). According to the results of Study I, microbiological pasteurisation was achieved in both treatments. Heating resulted in a relative discoloration. Similarly, specific smell of the watermelon changed to boiled fruit smell. In Study II, the samples taken on days of 0, 30, 90, 180 of the storage period were analysed to determine the microbiological activity. Results showed that higher numbers of aerobic mesophile bacteria (p<0.0001) and total clostridia (p<0.002) were determined in non-acidified groups compared to the acidified groups. During storage, the numbers of both groups of microorganisms increased on days 30 and 90 but decreased on day 180. During storage, more bloating were determined in non-acidified groups than found in acidified groups. Bloating were usually occured within the first week of the storage and not observed after all. Discoloration and smell change were not observed during storage. However, off-smell was determined more frequently in bloated cans. In study III, in analysis carried out to find out the period of use, higher numbers of total aerobic mesophile bacteria were found in non-acid group than acidified group on days 0, 2 and 4 after opening of the cans. As a result, acid additions + heat treatment application have become prominent in the project. All kinds of watermelon can be tinned. It has been revealed that depending on the purpose of usage, watermelon juice, watermelon puree and watermelon pulp can be produced.