Penentuan Umur Simpan Yoghurt Kacang Hijau (Phaeseolus radiatus, Linn).
Abstract
Mungbean include one of food plant that has been widely recognized by society, even the plants that belonging to the family of pulses has been long cultivated. In Indonesia, mungbean plant is the third-crop beans that are largely grown after soybean and peanuts. Because of its relatively high protein content and the price is relatively cheap, mungbean have a good prospect as a nutritious food that can be consumed by the public, so it is appropriate to be developed in order to increase their economic value. One alternative forms of processing, is to make yogurt from mungbean. However, the short shelf life of yogurt is sometimes become an obstacle, its because the ignoranced consumer about the storage of yogurt. To ensure that the yogurt is still worthy to consumed and not damaged, you need information about shelf life. This study aims to determine shelf life of mungbean yogurt and measuring the decline in the quality of yogurt during storage. This research was conducted with storing mungbean yogurt in the three different temperatures, that is 5 oC, 15 oC and 25 oC. And packaged in three different packaging, that is glass bottles, HDPE and PP. To determine the shelf life of mungbean yogurt, it use Extended Storage Studies (ESS) or the conventional method of determining the expiration date with in the way to save a product at normal conditions of daily and observed for its decrease quality until it reaches the quality level shelf. Quality parameters were analyzed during storage of yogurt that is fat content, protein content, pH, total acid, and the presence of coliform bacteria. The results for the initial characterization showed that the yogurt product having 4.06 in pH; total acid of 1.90%, 0.15% fat content, protein content of 7.85%, and negative values to test the presence of coliform bacteria. During the storage period there was a change of pH, total acid, fat and protein content, and presence of coliform bacteria. Critical parameters of shelf life of mungbean yogurt is the presence of coliform bacteria and total acid. Based on this research, for total acid as a critical parameters during storage, obtained that shelf life of mungbean yogurt is 21 days for yogurts that stored at 5 °C in glass bottle, HDPE and PP. Then, 18 days for yogurt that is stored on temperature of 15 oC in the packaging of HDPE, and 21 days for yogurt that packed with glass and PP packaging materials. Whereas, yogurt that stored at a temperature of 25 oC, has the shortest shelf life, its just six days for the products that are packed with every type of packaging, that are glass, HDPE and PP. For existence of coliform bacteria as a critical parameters, during storage at 5 °C, the yogurt that was not safe again to eat because of the presence of bacterial, is yogurt that packed with HDPE. For the yogurt that stored at a temperature of 15 oC, which already exceeds the safe limit of SNI is yogurt that packed with HDPE and PP. While, yogurt that stored at a temperature of 25 oC, there is no product that exceeds the safe limits of the presence of coliform bacterial from SNI.