Contents lists available at ScienceDirect Meat Science journal homepage: www.elsevier.com/locate/meatsci The impact of dietary supplementation with guava (Psidium guajava L.) agroindustrial waste on growth performance and meat quality of lambs Priscila T. Nobre a , Paulo E.S. Munekata b , Roberto G. Costa a , Francisco R. Carvalho a , Neila L. Ribeiro a , Rita C.R.E. Queiroga a , Solange Sousa a , André Carlos Raimundo da Silva a , Jose M. Lorenzo b, ⁎ a Federal University of Paraiba, Doctorate in Animal Science, 58.937-000 Areia, PB, Brazil b Centro Tecnológico de la Carne de Galicia, Rúa Galicia N° 4, Parque Tecnológico de Galicia, San Cibrao das Viñas, 32900 Ourense, Spain ARTICLE INFO Keywords: Guava by-product Sensorial analysis Carcass characteristics Physic-chemical properties ABSTRACT The aim of this study was to evaluate the growth performance and meat quality of lambs (40 animals) fed with increasing levels (0; 7.5; 15.0; 22.5 and 30.0%) of guava agroindustrial waste (GAW). The pH, cooking loss, colour and chemical composition were measured in the Longissimus lumborum (LL) muscle. A sensory analysis was performed with a panel of eight trained testers using a quantitative descriptive method in order to define sensory descriptors and their intensities. The lambs obtained a mean weight gain of 316 g/day consuming 1.32 kg/day of dry matter. The inclusion of GAW in the diet of lambs did not affect pH, L*, a* and b*. However, significant difference (P < .05) among the treatments were obtained for the chemical composition of LL: moisture decreased, while ash increased and intramuscular fat increased until 15% and then decreased at 22.5% with the inclusion of GAW. However, the sensorial characteristics of lamb meat (lamb odour and flavour, ten- derness and juiciness) were not affect by the inclusion of GAW. Therefore, GAW can be included up to 30% in lamb feed without compromising the performance, physic-chemical and sensory characteristics of meat. 1. Introduction The efforts to improve the production of sheep meat should be en- couraged toward the slaughter of young animals and fulfil the standards of international market (Montossi et al., 2013). The main characteristic of this market is its increasingly demanding nature in terms of product quality in the last years. However, the costs associated with feeding livestock become critical because feed prices have steadily increased during the last decade (Whitney & Smith, 2015). In this regard, low-cost feed ingredients based on agroindustrial by-products are potential al- ternatives that can reduce the cost of mixed feed, but the effects of these ingredients on animal performance and final products need to be fur- ther considered (Whitney & Smith, 2015). Worldwide, millions of tons of waste from agroindustrial activities are generated. The world fruit production reached 865.7 million tons in 2017, wherein, the three major producers, China, India, and Brazil, produced approximately 394.2 million tons of fruits in 2017 (FAO, 2019). Moreover, several agroindustrial by-products can be considered as functional feedstuffs because of their content of bioactive phytochemicals such as un- saturated fatty acids, sterols, tocopherols, carotenes, terpenes, polyphenols and others (Kalogeropoulos, Chiou, Pyriochou, Peristeraki, & Karathanos, 2012). Guava (Psidium guajava L.) is considered as a relevant perennial fruit crop in subtropical and tropical countries. The main countries produ- cing guava are India, China, Thailand, Pakistan, Mexico, Indonesia, and Brazil (Rajan & Hudedamani, 2019). Particularly for Brazil, its pro- cessing generates a waste (guava agroindustrial waste, GAW) composed of peel, seed and pulp and, which stands out as one of main by-products of the agroindustry and cause environment impact if inappropriately discarded in land fields (Chang, Tan, Lok, Pakianathan, & Supramaniam, 2014). Regarding GAW composition, it contains crude protein (39.5 g/kg dry matter), ether extract (16.3 g/kg dry matter), neutral detergent fiber (761.8 g/kg dry matter), acid detergent fiber (453.2 g/kg) and ash (10.0 g/kg dry matter) (Oliveira et al., 2018). Moreover, the lipid fraction of guava agroindustrial waste is pre- dominantly composed of unsaturated fatty acids, especially linoleic acid (77.35% of all fatty acids) (Uchôa-Thomaz et al., 2014). Additionally, GAW is rich in polyphenols, such as tannins (2–4%) which have a great antioxidant activity and may provide beneficial effects on protein metabolism in ruminants (Costa et al., 2018; Khalifa, https://doi.org/10.1016/j.meatsci.2020.108105 Received 28 June 2019; Received in revised form 27 February 2020; Accepted 27 February 2020 ⁎ Corresponding author. E-mail address: jmlorenzo@ceteca.net (J.M. Lorenzo). Meat Science 164 (2020) 108105 Available online 28 February 2020 0309-1740/ © 2020 Elsevier Ltd. All rights reserved. T