Fried convenience foods contain nutrients such as oil and protein, which are oxidized or decomposed by microorganisms or oxidized at high temperatures when encountering oxygen, resulting in small molecule acids that exceed the acid value of the food, causing rancidity, and releasing unique odors. In severe cases, they can volatilize a pungent hala flavor. So controlling acid value is one of the important measures to prevent rancidity in production.
Ⅰ、 Selection of food crude oil:
1. If the quality of oils used in food processing is poor and the storage environment is improper, it can lead to problems such as oxidation and rancidity of the food content.
2. The antioxidant capacity of different oil products varies, mainly due to the classification and content of antioxidants contained in the oil products. When oil is oxidized, it first reacts with the antioxidants in the oil, and then reacts with the oil itself after the antioxidant components are consumed. The higher the content of Unsaturated fat acid in oil, the easier it is to be oxidized.
3. Soybean oil has a high content of Unsaturated fat acids (more than 85%) and poor antioxidant capacity. However, palm oil contains half of Saturated fat acid and half of Unsaturated fat acid, as well as natural antioxidants, such as Tocopherol and tocotrienol, with strong antioxidant capacity, so palm oil is generally used for fried instant noodles. Of course, controlling the standard acid value and peroxide value of the raw oil is also important.
Ⅱ、 Adjustment of acid value during the production process of instant noodle machine equipment.
The main influencing factors include oil turnover rate, frying temperature, production continuity, metal ion pollution, timely separation of oil residue, and the use of antioxidants.
1. Turnover rate: In the process of making instant noodles, as the dough is produced, some fat will be taken away, so new oil should be continuously added to the fryer. The time (in hours) required to replenish new oil to completely update the fat in the fryer is called the frying oil turnover time (or turnover rate).
The relationship between the change time of instant noodle frying oil tanker and the increase in acid value: The shorter the change time of frying oil tanker, the lower the acid value of the oil, and the smaller the increase in acid value. On the contrary, the longer the turnover time, the higher the price of fatty acids, and the greater the increase in acid price.
2. Instant noodle machine frying temperature: In theory, the higher the temperature, the more likely it is to become sour. Therefore, in process design, high-temperature frying should be avoided. Through research and experiments, we at Dongfang Shangwu Food Machinery Co., Ltd. have reasonably designed the temperature gradient of instant noodle oil and frying time, and tried to avoid excessive frying at high temperatures during the cooking process.
3. Productivity and continuity: Long term continuous production has little impact on lubricating grease. If various factors that cause grease precipitation overlap, acidification will accelerate.
4. Metal ion pollution: This is mainly a new production line, and the oil pan equipment needs to be passivated.
5. Immediately separate the oil residue: This is very important, and there are usually several measures to ensure that the noodles entering the frying box are intact. Before entering the pot, try to pour as little sauce and auxiliary materials as possible, including soy sauce and various auxiliary materials added to the noodles, such as scallions, chocolate powder, etc. Minimize product pollution as much as possible.
Ⅲ、 Issues with food packaging
Unqualified outer packaging can easily cause air to enter the packaging and cause food oxidation, rancidity, etc. The issue of food packaging can be further divided into three aspects
1. Barrier properties, such as poor oxygen resistance of packaging materials, result in the oxidation of food ingredients caused by the slow infiltration of external air into the packaging during long-term storage of finished products. For example, some products with high oil content use composite films with poor composite effects as outer packaging materials. These materials have poor oil resistance, which can easily cause delamination of the composite film, leading to a decrease in overall packaging barrier.
2. Sealing, such as poor sealing caused by poor heat sealing, can lead to external air entering the packaging from the heat sealing area. In addition, some finished products that are not resistant to high-temperature cooking are prone to leakage at the sealing point after undergoing high-temperature cooking and sterilization, leading to a decrease in sealing performance.
3. Physical and mechanical properties, such as poor toughness of packaging materials, resistance to penetration of contents or rubbing or squeezing during production and storage, can lead to pinholes, creases, or even broken bags on finished product packaging during storage and transportation, which are not detected in a timely manner, leading to food contact with a large amount of oxygen and oxidation deterioration.
Our Dongfang Naomu Food Machinery Co., Ltd.'s fried instant noodle production line equipment has a reasonable structural design, strong adaptability to use, and is easy to operate in installation, use, maintenance, and other aspects. From initial consultation to plan setting, equipment manufacturing, to on-site installation and personnel training in the later stage, we wholeheartedly provide comprehensive system services and professional technical support to new and old customers.