可攜式牛肉熟成評估裝置之研製Development of a Portable Device for Maturation Evaluation of Beef

摘 要

受限於國內飼養條件，目前台灣牛肉的產量約為6至7千公噸，導致牛肉來源多以進口方式為主。由於進口牛肉需長時間的運輸，運輸過程的冷藏溫度與牛肉熟成的監控相當重要；除了確保品質外，良好的濕式熟程也能提升牛肉的嫩度與風味。近年許多文獻指出，牛肉的熟成可藉由組織纖維結構及生物阻抗特性的改變來監控，因此本研究將利用生物阻抗及彈性量測技術，建立一套可攜式牛肉熟成評估裝置。透過組織彈性量測機構，記錄按壓時的壓力與形變量，並進一步推算出楊氏模量。同時利用生物阻抗量測模組，評估阻抗模型的變化量。在進行連續7天的量測觀察中發現，隨著熟成的時間增加，裝置所量測的生物阻抗與組織彈性都有顯著的下降。在進一步的阻抗模型分析中，又以細胞外液的阻值具有決定性的阻抗量測影響；且分析模型對於額外的水分添加，也能有效區分出來。實驗證明本研究所開發的量測裝置具有評估牛肉熟成的潛力，未來希望能商轉為一低成本的牛肉熟成度評估裝置，讓消費者在購買牛肉時更加安心。

Abstract

Due to limitations in Taiwan's beef raising conditions, the domestic beef production is only about 6,000 to 7,000 tons, leading to reliance on import for beef supply. Since importing beef involves long transportation, the monitoring of refrigeration temperatures and beef aging during transportation is very important in Taiwan. In addition to ensuring beef quality, proper wet aging could also improve beef tenderness and flavor. Many research reports in recent years indicate it is possible to monitor beef aging based on changes in the tissue fiber structure and bioimpedance caused by beef aging. Therefore, a portable device for beef aging assessment was developed in this study, built using bioimpedance and elasticity measurement technologies. With a mechanism for tissue elasticity measurement, pressure imposed while pressing the tissue and associated deformation were recorded for further estimation of Young’s modulus. At the same time, variance in the impedance model was also assessed via a bioimpedance measurement module. During the measurement and observation for 7 consecutive days, it was found that both the bioimpedance and tissue elasticity measured by the device dropped significantly as the aging time increased. In a further impedance modeling analysis, impedance from extracellular fluids had a decisive effect on the level of impedance. The analysis model could also effectively discriminate extra added water. The experimental results prove that the measurement device developed in this study has the potential to assess beef aging. The device can be expected to be turned into a low cost device for beef aging detection in the future that can make consumers more reassured while purchasing beef.