**1. Introduction**

Meat identification and authentication is one of the applications for which near-infrared (NIR) spectroscopy is considered a valuable tool, as reported by different authors [1–7]. The utilisation of NIR spectroscopy has been reported by different researchers to have grea<sup>t</sup> success in identifying and differentiating between different meat species (e.g., beef, pork, lamb, and chicken) as well as authenticating different homogenized meat muscle samples from the same or different animal species [1–8]. The detection of adulterated, unauthentic, poor-quality, and unsafe meats is still a major task for the meat and food industries [9]. The meat industry as well as consumers have driven efforts to introduce innovative and reliable detection techniques that can ensure the authenticity, quality, and safety of both meat and meat products along the supply and value chains [3,5,10,11].

It has been recognised that the so-called classical analytical techniques are expensive, laborious, time-consuming, and not appropriate to the modern challenges facing the food and meat industries. Therefore, the demand to guarantee the authenticity and safety of both meat and meat products has increased the interest in developing rapid analytical techniques in food and meat industries [2–5]. Among these rapid techniques, vibrational spectroscopic techniques, such as NIR, mid-infrared (MIR), and Raman spectroscopies,

**Citation:** Hoffman, L.C.; Ingle, P.; Khole, A.H.; Zhang, S.; Yang, Z.; Beya, M.; Bureš, D.; Cozzolino, D. Characterisation and Identification of Individual Intact Goat Muscle Samples (*Capra* sp.) Using a Portable Near-Infrared Spectrometer and Chemometrics. *Foods* **2022**, *11*, 2894. https://doi.org/10.3390/ foods11182894

Academic Editor: David Bongiorno

Received: 4 September 2022 Accepted: 13 September 2022 Published: 18 September 2022

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are useful for the determination of meat quality and authenticity because of their intrinsic characteristics (e.g., rapid, reliable, non-destructive, green, relatively inexpensive) [2–5].

Although NIR spectroscopy has been applied to different commercial and exotic meats (e.g., beef, lamb, pork, chicken, kangaroo, game, etc.) [12–14], not many reports were found that evaluated the use of this technique to analyse goa<sup>t</sup> meat samples. Only one study has been reported that assessed the ability of NIR spectroscopy to characterise and authenticate the composition of goa<sup>t</sup> meat samples [15]. The authors of this study evaluated the use of NIR spectroscopy to estimate protein, moisture, connective tissue, ash, and fat contents in two goa<sup>t</sup> muscles, *Longissimus thoracis* (LT) and *L. lumborum* (LL), with grea<sup>t</sup> success (coefficient of determination > 0.70) [15].

Although the focus has been on the adulteration of meat using cheaper alternative species, few studies have evaluated the adulteration of expensive fresh meat cuts with cheaper cuts in the same animal species [16]. Typically, the more expensive cuts in a carcass differ in quality and composition from the inferior cuts or muscles. It is therefore of value to the industry to be able to distinguish between different muscles in a mixture of meat products (e.g., high- vs low-value muscle or commercial cuts), thereby providing proof of provenance and quality; a fillet steak sold as a high-value product due to its inherent quality characteristics is indeed derived from the *Psoas major* muscle and not from some inferior muscle.

Thus, the aim of this study was to evaluate the use of a portable near-infrared (NIR) instrument combined with linear discriminant analysis (LDA) to identify, as well as classify, individual and intact goa<sup>t</sup> muscle samples.

#### **2. Materials and Methods**
