allowing tofu to be sold at room temperature – are there no safety issues?
Takanobu Narita | nutritionist, Master of Health Sciences published photos of original Japanese articles at 13: 12 on December 4, 2016: Japanese grocery stores and supermarkets must keep unpaid Pictures/Aflo tofu and refrigerate for sale. Recently, it was reported that it is possible to save tofu at normal temperature. This raises the question, I\'m sure: is this safe? Why should tofu be refrigerated and sold at the beginning? In this article, I will try to explain the background of cold storage preservation and what changes will happen after the standard has been revised. ■ What food do you need to refrigerate? Among the various delicious food preservation methods, \"cold storage\" and \"freezing\" are probably the most typical. According to the preservation standard stipulated in the Food Hygiene Law, preservation below 10 °c or below is called refrigeration. When keeping food, the reproduction of microorganisms is the biggest problem. Mold and bacteria grow best in a humid, mild, nutritious environment. The theme of this article is tofu with these three conditions; Therefore, cold storage is considered a necessary condition for preservation. ■ The tofuPreservation standard for tofu was established in 1974. At that time, because of eating poorly preserved tofu, there was food poisoning, such as upper abdomen eczema. in order to prevent this from happening, it was decided that tofu must be preserved at low temperature. Tofu is a nutritious food that is easy to digest and absorb. The same is true of microorganisms, however. Depending on the preservation conditions, even a small amount of microorganisms can breed suddenly, causing food poisoning. In setting this standard, it is difficult to maintain sterility under manufacturing technology. Some people may be surprised to hear that tofu must be kept in cold storage. I believe many of you have seen tofu sold at room temperature in tofu shops and truck retailers in tofu. ( Note: In Japan, there are many shops specializing in tofu and retailers selling tofu such as cars. ) In fact, the standard of keeping tofu is set in Japan. Excerpt from \"tofu hygiene standards\" 2 preservation standards of tofu (1) Tofu must be refrigerated or fully cleaned and kept in a disinfection water tank with cold water ( Must be the water that makes food) Constantly being exchanged. However, this does not apply to tofu sold through Van retailers and tofu, which are sold immediately after molding without dipping into the water. (2) Tofu sold through a van retailer must be thoroughly cleaned and must be kept cool using disinfection equipment. Truck retailers in tofu shops and tofu do not have to refrigerate and sell tofu. Needless to say, of course, it is better to refrigerate the tofu purchased immediately and, if possible, on the day of purchase. The purpose of this proposed amendment is to change the above criteria for preservation and manufacture and to allow the sale of tofu at room temperature. I will explain the details in the next section. ■ The background of the revision of the tofu freshness standard is difficult and needs to be refrigerated. But you know, there are two kinds of tofu; One has a short shelf life and the other has a long shelf life? Firm (momen)and soft (kinugoshi) The tofu added in the plastic container of the moat has a short shelf life, while the shelf life of the filling is relatively long (juten) Tofu in a thick plastic container. Stuffed Tofu is made by directly sealing soy milk and curd at high temperatures The container is resistant and the container itself is heated and cooled. Soy milk is sealed in the container and heated; As a result, most of the bacteria are killed, which allows tofu to be kept safely for longer periods of time. The key to this proposed amendment is to modify the standard, because although the manufacture of stuffed tofu has become possible, it is safe even if it is kept at room temperature for a long time, unless the current standard is revised, otherwise it cannot be sold at room temperature. In fact, tofu produced in the same way has been sold at room temperature in the rest of the world, but there are no reports of food poisoning, and there seems to be a good record in terms of safety. ■ Aseptic filling tofuWill if the proposed amendment takes effect, can all the filled tofu currently sold be kept at room temperature? In fact, the recipe for filling tofu is different from manufacturer to manufacturer, and there are products that are not completely sterilized. There may be bacteria in the filled tofu that does not receive sufficient heat treatment, which may lead to food poisoning. According to the proposed amendment, the only product considered to be sold at room temperature is sterile stuffed tofu, and its manufacturing method can completely eliminate the bacteria that produce heat. Resistant spores In short, if no microorganisms survive in sealed foods, they cannot grow at room temperature; Therefore, even if tofu is kept for a long time, there is no need to worry about food poisoning. Aseptic filling tofu is a pressure/heat sterilized tofu ( More than 4 minutes at 120 °c) This will kill dangerous heat-resistant bacteria like Botox. Tofu without this heating requirement must be refrigerated for sale as before. Strictly speaking, aseptic filling of tofu meets the following requirements. 【 Requirements for aseptic filling(1) The microorganisms present in food come from their classification. Food that can grow in food must be killed or eliminated in a way that has sufficient destruction or elimination effects. Soybean milk, 120 ℃/4 minutes; For condensate, highly hygienic condensate must be used with the appropriate filter and must be disinfected while the filtration capacity is continuously confirmed during the manufacturing process; Quite or higher. (2) Tofu must be filled in containers using equipment suitable for aseptic filling and using sterilized appropriate containers and packaging. (3) The final product must be negative for microorganisms that can grow under the test method specified in the \"retort bag food\" ingredient standard. ■ SummaryI asked an official of the Ministry of Health that the Labor and Welfare Organization was informed that the proposal was only accepted by an expert committee and that there were several procedures to be processed before the standards were revised. In addition, it is still unclear when the standard can be actually revised. Even if the standard is modified, tofu other than aseptic filling of tofu needs to be kept as before, so please do not misunderstand that tofu can be kept at room temperature. The preservation of sterile filling tofu at normal temperature is of social significance and hopes to be realized as soon as possible. Such tofu can be preserved and distributed as emergency food for disasters at such times. In addition, the impact of cooling costs and reduced energy resources can be expected. I\'m looking forward to seeing the normal-temperature tofu on hold in the store, isn\'t it? 【 Abstract of this article] Tofu needs to be refrigerated as it meets all the conditions required for microbial easy reproduction. Due to technological advances and other reasons, disinfected tofu can now be produced. Sterile stuffed tofu can actually be kept at room temperature, but must be refrigerated under current law. The purpose of the revised standard is to allow only sterile filling of tofu to preserve tofu at room temperature. The revision may take several years, as there are some procedures before the revision of the standards after the adoption of the expert committee. As a reference material, this article uses the materials used by the pharmaceutical Food Hygiene Committee ( Food hygiene committee of Food Standards Committee) On November 29, 2016, the Ministry of Health, Labor and Welfare held a meeting on \"Revision of tofu standards and standards. An excerpt from this article is written based on the same material.