Application Plan of Low-Field Nuclear Magnetic Resonance Technology in the Food and Agriculture Sector

I. Overview of Applications

Moisture is a major component in many foods. Each food has a specific moisture content that is present in a particular amount and spatial distribution, directly influencing the structure, appearance, spoilage sensitivity, and processing characteristics of the food. Among various technologies, nuclear magnetic resonance (NMR) — particularly proton-based NMR — has become one of the most widely studied due to its ability to analyse moisture. As early as the 1950s, the United States began applying NMR to investigate hydration in food systems.

Conventional moisture analysis methods often fail to capture the mobility and distribution of water in food matrices. In contrast, NMR and its imaging counterpart offer a highly effective and non-destructive way to study the diffusion and distribution of water, lipids, and sugars — all of which provide critical structural and environmental information throughout processing and storage. These advantages have led to the widespread adoption of NMR in both academic food science research and industrial quality control systems.

II. Solutions

1. Sea Cucumber Rehydration Analysis

During early soaking, external water enters the sea cucumber and becomes intracellular water, increasing the bound water (A22) content. As soaking continues, the internal structure expands and A22 gradually migrates to free water (A23). The overall water activity in the sea cucumber increases as rehydration progresses.

2. Comparison of Moisture and Oil Content in Foods

· Accuracy: Deviation less than 0.5%

· Repeatability: Standard deviation less than 0.1%

· Stability: Standard deviation less than 0.5%