The energy-saving and emission-reduction effect of Nisin in extending the shelf life of food

The energy-saving and emission-reduction effects of Nisin in extending food shelf life are mainly achieved through three core pathways: reducing thermal processing energy consumption, lowering cold chain turnover consumption, and cutting invalid energy consumption caused by food waste. Compared with traditional processes (high-temperature sterilization, chemical preservation), the comprehensive energy-saving and emission-reduction rate can reach 20%–45% for different food categories, and the energy-saving potential becomes more significant as the production scale expands.

I. Core Pathways for Energy Saving and Emission Reduction: Full-Chain Consumption Reduction from Processing to Storage

1. Reducing Thermal Processing Intensity: Directly Cutting Heating Energy Consumption and Carbon Emissions

Traditional food preservation relies on high-temperature sterilization (e.g., 121°C high-pressure sterilization, 95°C pasteurization), which consumes large amounts of electricity or thermal energy. Energy consumption increases exponentially with higher temperatures and longer durations. After adding Nisin, it can target and inhibit Gram-positive bacteria and their spores (the main cause of food spoilage), significantly reducing thermal processing parameters:

In meat products (e.g., low-temperature ham): The traditional process requires heating at 75°C for 20 minutes, with energy consumption of approximately 80 kWh/ton. After adding 200 IU/kg Nisin, the temperature can be reduced to 65°C and the time shortened to 10 minutes, lowering energy consumption to 45 kWh/ton—a direct energy reduction of 43.75%. Calculated based on thermal power (approximately 0.82 kg CO₂ per kWh), this reduces carbon emissions by 28.75 kg per ton of product.

In dairy products (e.g., pasteurized milk): The traditional 95°C/5-minute pasteurization consumes about 60 kWh/ton. After adding 300 IU/kg Nisin, 85°C/3-minute sterilization can be used, reducing energy consumption to 35 kWh/ton—a 41.67% energy reduction and 20.5 kg/ton carbon emission reduction.

Core logic: Energy consumption of high-temperature sterilization is positively correlated with temperature (energy consumption increases by 15%–20% for every 10°C temperature rise). By replacing part of the high-temperature sterilization function, Nisin avoids "excessive heating" and reduces energy consumption at the source.

2. Extending Shelf Life: Reducing Indirect Energy Consumption from Cold Chain and Repeated Processing

Nisin can extend food shelf life by 2–3 times, breaking the "small-batch, high-frequency" production and transportation mode of traditional short-shelf-life foods, and indirectly reducing energy consumption from cold chains and repeated processing:

For fruits and vegetables (e.g., strawberries, lychees): The traditional room-temperature shelf life is only 1–2 days, requiring full cold chain (0–4°C) transportation with energy consumption of approximately 50 kWh/ton. After spraying with a 0.1% Nisin solution, the shelf life extends to 5–7 days, reducing 1–2 replenishment transports and lowering cold chain energy consumption to 30 kWh/ton—a 40% energy reduction.

For baked goods (e.g., bread): The traditional shelf life is 3–5 days, requiring daily production (oven heating energy consumption of 30 kWh/ton). After adding 150 IU/kg Nisin, the shelf life extends to 10–12 days, reducing production frequency to once every 3 days and lowering heating energy consumption to 12 kWh/ton—a 60% energy reduction.

Key value: The "high-frequency" mode of short-shelf-life foods leads to frequent equipment startups/shutdowns and repeated transportation trips, resulting in extremely high energy density. After Nisin extends the shelf life, the mode shifts to "large-batch, low-frequency," which spreads the energy consumption per unit product.

3. Reducing Food Waste: Lowering the Proportion of "Invalid Energy Consumption"

Food waste is essentially "energy consumed in production, processing, and storage that does not generate value." By extending shelf life to reduce waste, Nisin indirectly lowers the energy consumption per unit of usable food:

The global food waste rate is approximately 1/3. For every 1 ton of meat products wasted, it is equivalent to wasting 800 kWh of processing and cold chain energy. Adding Nisin can reduce food waste rate by 20%–30%. Calculated on this basis, every 10,000 tons of food can reduce 1.6–2.4 million kWh of "invalid energy consumption," corresponding to a carbon emission reduction of 131.2–196.8 tons (calculated based on thermal power).

Taking low-temperature sausages as an example: The traditional shelf life is 15 days with a 15% waste rate; after adding Nisin, the shelf life extends to 30 days and the waste rate drops to 5%. Every 10,000 tons of products can reduce waste by 100 tons, corresponding to saving 80,000 kWh of energy—equivalent to a 6.56-ton CO₂ emission reduction.

II. Differences in Energy-Saving and Emission-Reduction Effects Across Food Categories

The energy-saving and emission-reduction effects of Nisin vary by food processing technology and shelf life requirements, with more prominent effects in categories requiring low-temperature processing and high-energy sterilization:

1. Low-Temperature Meat Products (Ham, Sausages): Optimal Energy-Saving and Emission-Reduction Effects

The traditional process relies on heating at 70–80°C for 15–20 minutes, with high cold chain storage energy consumption and a 15–20-day shelf life. After adding Nisin:

Heating temperature is reduced to 60–65°C, time shortened to 8–10 minutes, and shelf life extended to 30–40 days.

Processing energy consumption is reduced by 35%–45%, cold chain energy consumption by 25%–30%, and comprehensive energy-saving and emission-reduction rate reaches 30%–40%.

2. Dairy Products (Pasteurized Milk, Cheese): Significantly Reducing Sterilization Energy Consumption

Traditional pasteurized milk requires heating at 90–95°C for 5–10 minutes with a 7–10-day shelf life. After adding Nisin:

Heating temperature is reduced to 75–80°C, time shortened to 3–5 minutes, and shelf life extended to 14–21 days.

Sterilization energy consumption is reduced by 25%–35%, cold chain turnover energy consumption by 30%, and comprehensive energy-saving and emission-reduction rate reaches 20%–30%.

3. Fruit and Vegetable Products (Fruit and Vegetable Juices, Prepared Fruits/Vegetables): Reducing Cold Chain Dependence

Traditional fruit and vegetable juices require 85–90°C sterilization with a 15–20-day shelf life; prepared fruits/vegetables rely on cold chains with a 3–5-day shelf life. After adding Nisin:

Fruit and vegetable juice sterilization temperature is reduced to 70–75°C, shelf life extended to 30–40 days; prepared fruits/vegetables shelf life extended to 7–10 days.

Processing energy consumption is reduced by 20%–25%, cold chain energy consumption by 40%–50%, and comprehensive energy-saving and emission-reduction rate reaches 25%–35%.

4. Baked Goods (Bread, Cakes): Reducing Production Frequency

Traditional baked goods use no high-temperature sterilization, rely on chemical preservatives, have a 3–5-day shelf life, and require daily production. After adding Nisin:

Shelf life is extended to 7–10 days, production frequency reduced to once every 2 days.

Oven heating energy consumption is reduced by 40%–50%, transportation energy consumption by 30%, and comprehensive energy-saving and emission-reduction rate reaches 35%–45%.

III. Practical Application Potential and Optimization Suggestions

Taking a factory with an annual output of 10,000 tons of low-temperature ham as an example: After optimizing the process with Nisin, it can reduce processing and heating energy consumption by 350,000 kWh, cold chain storage energy consumption by 216,000 kWh, and food waste by 100 tons annually. This corresponds to a total energy saving of 566,000 kWh and a CO₂ emission reduction of 49.4 tons (calculated based on thermal power)—equivalent to reducing 200 tons of standard coal combustion (1 ton of standard coal generates approximately 2,800 kWh of electricity).

To maximize the effects, two points should be noted:

Synergize with other technologies (e.g., combining with cinnamon extract) to further reduce thermal processing temperature (additional 10%–15% energy reduction).

Control the addition amount (add 70%–80% of the national standard upper limit) to ensure shelf life while avoiding excessive costs offsetting energy-saving benefits.

Nisin is not only a natural preservative but also an important technical support for the "low-carbonization" of the food industry. By reducing energy consumption and waste across the entire chain, it brings a 20%–45% comprehensive energy-saving and emission-reduction effect to different food categories. The larger the scale and the higher the demand for high-temperature processing, the more significant the energy-saving potential—aligning with the trend of green production.