Autofluorescence quantifies collagen in sausage batters with a large variation in myoglobin content

In order to clarify the potential of the method of autofluorescence for determining the collagen content in meat batter, an experimental design was used where the emission originating from collagen was unrelated to the effect of myoglobin absorbance on the emission spectra. Muscles like beef Masseter, beef Latissimus dorsi and pork Glutens medius assured a large variation in myoglobin content, and made absorbance from myoglobin account for 65–84% of the variation in the emission spectra at wavelengths normally thought interesting for collagen quantification. Collagen (range 1.3–4.0%) accounted for 7–18% of the variation in the autofluorescence emission spectra. Collagen content could be predicted from the emission spectra provided multivariate regression techniques were used. Pre-processing of spectra reduced the prediction error for collagen by 0.03–0.12%, depending on method used; the lowest prediction error obtained being 0.48%. The method of autofluorescence gave lower prediction errors for collagen content than did the method of near infrared reflectance when applied to the same batters.