Deskripsi Proyek

Retort is a tool for sterilizing food that has been canned. Sterilization is a thermal process carried out at high temperatures >1000C with the main objective of destroying pathogenic and spoilage spores. A product is said to be sterile if no microbes can grow on the product. Bacterial spores are more heat resistant than their vegetative cells. The working principle of the retort is that the heating element in the retort will heat water to form hot steam. This hot steam will expel air from the retort, thus forming pure hot steam. The pure hot steam is used to heat the material contained in the container. The amount of heat required for adequate sterilization depends on several factors, including the size of the can and its contents and the pH of the food. Food sterilization is more accurately called commercial sterilization, meaning a process to kill all microorganisms that can cause food spoilage. Under microscopic storage conditions withstand the sterilization process, but are unable to reproduce at the normal storage temperature specified for the food. Commercial sterilization has two types, namely the type of sterilization in packaging (in batch sterilization), where the material and packaging are sterilized together after the material is canned, and the aseptic type (in flow sterilization), where the material and packaging are sterilized separately and then the material is put into the packaging. in sterile or aseptic conditions. Pasteurization, like blanching, is a thermal process carried out at temperatures below 100 0C. The time required for sterilization depends on the high temperature used (Bellitz, 1999). The higher the pasteurization temperature, the shorter the time required for heating. The main purpose of the thermal process in pasteurization is to inactivate vegetative cells from pathogenic microbes. The tool for pasteurization is a pasteurizer which has the following working principle: material in the form of a liquid is flowed into a heat exchanger so that heat transfer occurs. Heat through the plate is transferred from the heating water to the material. Heating water comes from a water tank that is heated by electric heat, then flows in the opposite direction to the direction of the material flow. The heating time for the product occurs as long as the product flows in the holding tube. If the process is deemed insufficient, the material will be returned to the heat exchanger and holding tube. Material exits the cycle and enters the product container when the process is deemed sufficient. Flow regulation is done through the control valve. Pasteurization can be carried out using hot water that is supplied intermittently (batch) with a low temperature system and a long time (Low Temperature Long Time), or by using a continuous flow of hot water with a high temperature system and a short time (High Temperature Short Time). ). In the case of a pressure retort sterilization process, the heating medium used is saturated steam. It is necessary to ensure that all parts are inside the retort

has been filled with saturated steam, and no more air is trapped in the retort. If the retort still has air pockets, the heating efficiency will be reduced and the temperature that occurs in each part of the retort will not be evenly distributed, which in turn will result in insufficient heat being experienced by the food during the sterilization process. In this case, it is very important to pay attention to the venting procedure and the venting schedule as well as the time to achieve the come up time. By carrying out the correct venting procedure, it can be guaranteed that the retort is completely filled with saturated steam evenly and has the same heating temperature in every part of the retort. By testing the heat distribution, it will be known the heating profile of each part of the retort during the venting and heating processes. So that through this heat distribution test it can be determined sufficient venting and come up time to ensure an even distribution of heat in the retort. The occurrence of an even distribution of heat is also influenced by factors including the volume of saturated steam supplied, the condition of the steam spreader section, as well as the condition of other equipment and piping in the retort.