Improvement of lactic acid bacteria viability in acid conditions employing agroindustrial co-products as prebiotic on alginate ionotropic gel matrix co-encapsulation Victor Serrano-Casas a , M. Lourdes Pérez-Chabela a , Edith Cortés-Barberena b , Alfonso Totosaus c,⇑ a Biotechnology Department, Universidad Autónoma Metropolitana Iztapalapa, Av. San Rafael Atlixco 86, Mexico City 09340, Mexico b Health Sciences Department, Universidad Autónoma Metropolitana Iztapalapa, Av. San Rafael Atlixco 86, Mexico City 09340, Mexico c Pilot Plant and Food Science Lab, Tecnológico de Estudios Superiores Ecatepec, Av. Tecnologico esq. Av. Central, Ecatepec 55210, Estado de México, Mexico article info Article history: Received 26 April 2017 Received in revised form 6 September 2017 Accepted 14 September 2017 Keywords: Lactic acid bacteria Co-encapsulation Agroindutrial co-product Probiotic Prebiotic Symbiotic abstract Waste from foods processing are being widely studied due their content of many value added ingredients, like dietary fiber and bioactive compounds. The opportunities for recovery of components with a great economic potential from by-products are diverse. Apple marc derived from cider production and cactus pear peel flour, a popular consumed fresh fruit, besides inulin as control, were employed for co- encapsulation of probiotic thermotolerant lactic acid bacteria in alginate ionotropic gel matrix. Lactic acid bacteria viability, enhanced acid conditions resistant, where a higher microcapsule size was related to better viability and longer times resisting acid conditions. Inulin and apple marc resulted in higher micro- capsules size (close to 100 mm) that could be employed to ensure the delivery of probiotic strains in colon throughout the gastro intestinal tract. Ó 2017 Elsevier Ltd. All rights reserved. 1. Introduction Food waste production covers the food life cycle from agricul- ture, transformation, retail and consumption, where in developed countries 39% of the losses occur in the transformation process. Food waste can be employed as raw material for new products and applications, since many residues have the potential to be reused in other production systems (e.g. biorefineries as a source of alternative energy, like ethanol). Besides, industrial symbiosis in recovering waste from food processing can be focus to obtain high added-value functional ingredients to be applied in the nutraceutical and pharmaceutical industry (Mirabella, Castellani, & Sala, 2014). Food industry faces the challenge to meet the increasing demand for food supplies, related to healthier products for a more balanced diet. Food processing is associated with the production of large waste or by-product streams, since not all parts of the plants can be consumed, like seeds and peels. In addition, since these parts have not been traditionally included in the diet, consumer acceptance is low and those parts are discarded. These by-products are an abundant source of biopolymers, such as proteins and carbohydrates, like dietary fiber, and bioactive components, such as carotenoids and phenolic compounds, and the opportunities for recovery of components from by-products are diverse with a great economic potential (van der Goot et al., 2016). Apple and Opuntia cactus are important part of agroindus- trial productive chains. In Mexico, during 2015 the apple produc- tion reached 716.865 thousand tons. In Puebla region, 27.2 thousand tons of apple were produced during same period, des- tined mainly to cider production (around 240,000 l), generating an important amount of disposal as apple marc. Mexico is the main producer of cactus pear. Opuntia cactus pear production was around 352 thousand tons in 2015. Cactus pear is a cheap fruit with relatively high fiber content and hypoglycemic effect, but peel is not consumed (SAGARPA, 2016). Both apple marc and cactus pear peel are good alternatives to be employed as prebiotic ingredients. Prebiotic is now defined as ‘‘a selectively fermented ingredient that allows specific changes, both in the composition and/or activ- ity in the gastrointestinal microbiota that confers benefits upon host wellbeing and health” (Roberfroid, 2007). The effects on colo- nic flora and on the biochemistry and histology of the host bowel of prebiotics are associated with optimized colonic function and metabolism, increased fecal weight, a reduction in luminal colon pH, a decrease in nitrogenous end products and reductive enzymes, besides immune system modulation, supporting the logic of the http://dx.doi.org/10.1016/j.jff.2017.09.048 1756-4646/Ó 2017 Elsevier Ltd. All rights reserved. ⇑ Corresponding author. E-mail address: alfonso.totosaus@gmail.com (A. Totosaus). Journal of Functional Foods 38 (2017) 293–297 Contents lists available at ScienceDirect Journal of Functional Foods journal homepage: www.elsevier.com/locate/jff