冷藏、冷凍和斃死豬大里肌肉的判別

Abstract

有鑑於近年來斃死豬肉的問題不斷被披露，不但影響消費者的信心，更對養豬業者造成難以估計的損失。為了避免不肖業者以斃死豬肉欺騙消費者而謀取暴利，保障生產者，及維持市場秩序，有必要研究發展客觀及快速判別斃死豬之大里肌肉的方法。探討可見光/近紅外光技術、機器視覺、pH値與肉色標準(PCS)作為判別斃死大里肌肉之可行性。 以2nm間隔的可見光/近紅外光光譜值，利用Unscrambler7.6軟體之部份最小平方迴歸，搭配虛擬迴歸技術分析，選擇400-2198nm作為變數可以96.8%判別冷藏和斃死豬大里肌肉；選擇波長472-524nm作為變數，可以87.5%判別冷凍再解凍與斃死豬大里肌肉；選擇波長400-2198nm作為變數，可以96.8%的判別冷藏和正常冷凍再解凍豬大里肌肉。 使用RGB值、HSI值及Lab值作為變數，利用最小平方迴歸搭配虛擬迴歸技術分析，可以96.7%判別冷藏和斃死豬大里肌肉、90.3%判別冷凍再解凍與斃死豬大里肌肉，以及81.2%的判別冷藏和正常冷凍再解凍豬大里肌肉。 冷藏、冷凍再解凍和斃死豬大里肌肉之平均pH值分別為5.89±0.21、5.91±0.23和5.80±0.13。正常冷藏、正常冷凍再解凍和斃死大里肌肉之平均肉色標準分別為2.33±0.58、2.53±0.58和1.94±0.96。

For the last few years, the problem of cadaveric pork has been published in the newspaper continuously. Consequently, this may result in affecting consumer confidence, and unpredictable loss on the pork industry. To avoid illegal cheating, to protect producers and to maintain market order, it is necessary to develop a rapid method to validate cadaveric longissimus. The feasibility of validating cadaveric longissimus has been studied by visible/near-infrared spectroscopy, machine vision, pH value, and Pork Color Standard (PCS). By the visible/near-infrared spectra with 2nm interval, partial least square regression from Unscrambler7.6 software and dummy regression techniques, the validation rate of chilled and cadaveric pork longissimus was 96.8% in the 400-2198 nm range. The validation rate of frozen-then-thawed and cadaveric pork longissimus was 87.5% in the 472-524 nm range. In the 400-2198 nm range, the validation rate of chilled and frozen-then-thawed pork longissimus was 96.8%. Using RGB, HSI and Lab values, the validation rate of chilled and cadaveric pork longissimus was 96.7%. The validation rate of frozen-then-thawed and cadaveric pork longissimus was 90.3%, and 81.2% for chilled and frozen-then-thawed pork longissimus. The average pH values of chilled, frozen-then-thawed and cadaveric pork longissimus were 5.89 ± 0.21, 5.91 ± 0.23, and 5.80 ± 0.13, respectively. The pork color standard (PCS) of chilled, frozen-then-thawed and cadaveric pork longissimus were 2.33 ± 0.58, 2.53 ± 0.58, and 1.94 ± 0.96, respectively.