Natural Occurrence of Ochratoxin A and Antioxidant Activities of Green and Roasted Coffees and Corresponding Byproducts

Abstract

Ochratoxin A is an important mycotoxin that can enter the human food chain in cereals, wine, coffee, spices, beer, cocoa, dried fruits, and pork meats. Coffee is one of the most common beverages and, consequently, it has a potential risk factor for human health related to ochratoxin A exposure. In this study, coffee and corresponding byproducts from seven different geographic regions were investigated for ochratoxin A natural occurrence by HPLC-FLD, nutritional characterization, and antioxidant activities by spectrophotometric assay. The research focused on composition changes in coffee during the processing step "from field to cup". Costa Rica and Indian green coffees were the most contaminated samples, with 13 and 11 microg/kg, respectively, while the Ethiopian coffee was the least contaminated, with 3.8 microg/kg of ochratoxin A. The reduction of ochratoxin A contamination during the roasting step was comparable for any samples that were considered under the recommended level of 4 microg/kg. Total dietary fibers ranged from 58.7% for Vietnam and 48.6% for Ivory Coast in green coffees and ranged from 58.6% for Costa Rica to 61.2% for India in roasted coffee. Coffee silverskin byproduct obtained from Ivory Coast was the highest, with 69.2 and 64.2% of insoluble dietary fibers, respectively.

The influence of roasting and additional processing on the content of bioactive components in special purpose coffees

“…For example Perrone et al (2012) observed the highest antioxidant activity for green coffee, while Duarte et al, (2005) indicated that degree of roasting is inversely correlated with antioxidant activity and observed the highest values for light roasted coffee. Different results were obtained by Del Castillo et al (2002) and Napolitano et al (2007), who found that light and medium roasted coffee displayed greater antioxidant activity than green coffee. Moreover, the results presented by Vignoli et al (2014) indicated that antioxidant activity of coffee may be constant during roasting and is dependent on the balance of the compounds formed during this process.…”

Development of polylactic acid nanocomposite films reinforced with cellulose nanocrystals derived from coffee silverskin

“…Most recent studies on this issue have focused on the potential use of CS with advances in industrial biotechnology; for example, CS could be considered as a functional ingredient for food due to its antioxidant capacity and high concentration of soluble dietary fibers (Esquivel & Jiménez, 2012;Pourfarzad, Mahdavian-Mehr, & Sedaghat, 2013). Furthermore, CS contains high levels of phenolic compounds, which enhance human health through their antioxidant activity (Borrelli, Esposito, Napolitano, Ritieni, & Fogliano, 2014;Napolitano, Fogliano, Tafuri, & Ritieni, 2007) and high prebiotic activity (Jiménez-Zamora, Pastoriza, & Rufián-Henares, 2015). According to Ballesteros et al (2014), CS consists mainly of polysaccharides, such as in the form of cellulose (24%) and hemicellulose (17%), and 4 lignin (29%).…”

Influence of extraction process on antioxidant capacity of spent coffee

“…Furthermore, during the last few years an increasing number of studies have shown the presence of phytochemicals related with health benefits in coffee residues (Borrelli, Esposito, Napolitano, Ritieni, & Fogliano, 2004;Ramalakshmi, Jagan Mohan Rao, Takano-Ishikawa, & Goto, 2009). In the case of silverskin, some authors have demonstrated the presence of high amounts of dietary fiber as well as antioxidant activity (Borrelli et al, 2004;Napolitano, Fogliano, Tafuri, & Ritieni, 2007). Also in the residues obtained during processing of soluble coffee, antioxidant properties, which may be attributed to phenolic and nonphenolic compounds, have been found (Pushpa & Madhava Naidu, 2010;Ramalakshmi et al, 2009;Yen, Wang, Chang, & Duh, 2005).…”