Twenty years of cold chain

Chapter 28 Plan Table

Hu Shutong officially devoted himself to the formulation of the HACCP fresh-cut vegetable work plan. This task left by his mentor Pang was also a test for him. Hu Shutong knew it was important. If he could gain Pang's approval, it would be a great sense of accomplishment.

Freshly cut vegetables have a very low market share in the current vegetable market. These vegetables are transported directly to supermarket freezers after semi-processing. However, not many people go to supermarkets to buy vegetables these days. Primary agricultural products in the vegetable market, such as potatoes with soil and roots and whole cabbages, are people's first choice.

However, with the rapid improvement of people's living standards, it is an inevitable trend to choose fresh-cut vegetables that are more refined, do not require cutting or peeling, and allow for more flexible portion selection.

Hu Shutong was already aware of this background, so he was well-informed from the start of this planning process. Undoubtedly, the vegetable company was going to take a more refined approach, which would result in higher premiums for agricultural products.

When Hu Shutong focused his attention on this matter, he suddenly felt excited. If he were to come up with a set of procedures, a fresh graduate would lack the persuasiveness of practical experience. Even if he were a student from the University of Minnesota, a company might not dare to use him. Moreover, Hu Shutong didn't even have a channel to submit the procedures.

But with Professor Pang ahead of him, everything will be completely different. What he is doing now is very likely to be transformed into practical results, which is what Hu Shutong has always been pursuing. His paper describes a grand vision for the industry, and no one knows when it will be realized, but no matter when, every step towards it will be solid. As Professor Pang said, things must be done one by one.

With this thought in mind, Hu Shutong felt even more motivated.

This system originated in Europe and America more than 20 years ago, and a small number of processing companies in China are already using it for fresh-cut vegetables. However, the usage varies widely, with different temperature controls in the cutting and packaging rooms, and different pesticide cleaning methods. He deeply understands Pang Shiyou's intention: it's still a matter of standardization.

Using the university's labs where experiments were frequently conducted, Hu Shutong began conducting experiments day after day. Although the equipment was limited, it was more than enough for this project.

After vegetables are cut, their tissues are mechanically damaged, their natural protective layer disappears, and they are stimulated to produce a large amount of anaerobic respiration, making them more prone to spoilage. Hu Shutong's focus is on monitoring the physiological and biochemical reactions of vegetables after cutting, including enzymatic and non-enzymatic browning. These are major courses in the food science department, such as food chemistry and nutrition. However, because Hu Shutong is more familiar with cold storage environments, low-temperature systems, and storage and distribution, he is more adept at the operation.

All of these experiments are aimed at obtaining the final critical limits, which are the core of the critical control points. This is similar to the equipment operation procedures that Hu Shutong developed at Tianheng. The most important things to pay attention to are selected, and the procedures are followed step by step. The staff do not need to understand the principles, but only need to strictly follow them.

Hu Shutong has been working on this project for half a month, and it's already early August. He still hasn't been able to come up with a complete process that satisfies him, and he's still experimenting with temperature control. During this time, he visited several fresh-cut vegetable supermarkets in the city, and the scene was rather bleak. After communicating with the sales staff, he also discovered many practical problems. For example, the problem of vegetables softening and hardening is very common. They arrive looking fresh and bright, but overnight they either collapse and leak water or their color changes drastically.

The entire process is divided into raw material acceptance, cutting, cleaning, packaging, metal detection, storage and distribution. Among them, cutting, cleaning and packaging are the parts that Hu Shutong spends the most time on.

In the final plan, Hu Shutong set the temperature in the cutting room at 5°C and the time spent in the cutting room should not exceed five minutes; the vegetable washing should use sodium hypochlorite with a concentration strictly controlled between 120 and 180 mg/L, the washing water temperature at 5°C, the pH value not exceeding 7, and the washing time not exceeding three minutes; the packaging room should be set at 5°C, and the vegetables should not be moved into the high-temperature warehouse for more than four minutes, with the high-temperature warehouse set at 0 to 4°C.

The vertical axis of the plan includes descriptions of significant hazards, critical limits, monitoring frequency, corrective actions, recording methods, and so on.

Hu Shutong spent another three days checking for leaks until he was satisfied before stopping his work. Then he collapsed onto his bed and had a good, restful sleep.

In his dream, he was in a cold storage room, where an invisible fruit knife was waving in the air. He saw neatly arranged chunks of winter melon, halved cabbages, eight-centimeter sections of yam, and rearranged broccoli heads, brightly washed bok choy, lettuce, and baby bok choy on the worktable. A little while later, he was in a supermarket, this time surrounded by large hands. People were carrying shopping baskets in front of the refrigerated display cases, putting boxes into their baskets one by one.

Moreover, in my dream, people praised me endlessly, giving me a thumbs up and saying that it was natural, healthy, and safe. There were also many microphones pointed at me, and I suddenly became the center of attention. I was so beautiful that I lost all sense of proportion.

"Wow! You're making me laugh! You dreamt you were getting married!"

Jiang Zhipeng came over to call him, but the phone was still there, so he had no choice but to disturb his sleep. "Old Hu! Old Hu! You have a call!"

"You're so annoying! I'll punch you when I have time!"

"You're amazing! Professor Pang is looking for you!"

"Huh?" Hu Shutong sat up abruptly, reached for his phone and saw that it was out of battery. He quickly got out of bed to answer the dormitory call.

"Professor Pang, I've finished the schedule and will deliver it to your office right away!"

"Shutong, I haven't gone back to school yet. If you have time, bring your schedule and come to the southern suburbs. I'm at the Huihong Hotel. Call Xiao Wu in advance when you arrive."

"Okay, Professor, I'll be off right away."

After hanging up the phone, Hu Shutong was still in a daze, and Jiang Zhipeng was also stunned. "Old Hu, how did you get involved with Professor Pang?"

"I'll punch you in the face!"

Hu Shutong didn't have time to say anything more and quickly charged his phone. As soon as the screen lit up, Jiang Zhipeng handed him his phone, saying, "If you're in a hurry, take mine."

"Thanks!" Hu Shutong grabbed the bag and hurriedly left the dormitory.

"Oh, by the way, a girl called me. Keep an eye on things! If any of them cause me trouble, I'll cripple you!"

……