Browsing by Subject "Coffee"

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    Novel method for the detection of adulterants in coffee and the determination of a coffee's geographical origin using near infrared spectroscopy complemented by an autoencoder
    (2023) Munyendo, Leah; Njoroge, Daniel; Zhang, Yanyan; Hitzmann, Bernd
    Coffee authenticity is a foundational aspect of quality when considering coffee's market value. This has become important given frequent adulteration and mislabelling for economic gains. Therefore, this research aimed to investigate the ability of a deep autoencoder neural network to detect adulterants in roasted coffee and to determine a coffee's geographical origin (roasted) using near infrared (NIR) spectroscopy. Arabica coffee was adulterated with robusta coffee or chicory at adulteration levels ranging from 2.5% to 30% in increments of 2.5% at light, medium and dark roast levels. First, the autoencoder was trained using pure arabica coffee before being used to detect the presence of adulterants in the samples. Furthermore, it was used to determine the geographical origin of coffee. All samples adulterated with chicory were detectable by the autoencoder at all roast levels. In the case of robusta‐adulterated samples, detection was possible at adulteration levels above 7.5% at medium and dark roasts. Additionally, it was possible to differentiate coffee samples from different geographical origins. PCA analysis of adulterated samples showed grouping based on the type and concentration of the adulterant. In conclusion, using an autoencoder neural network in conjunction with NIR spectroscopy could be a reliable technique to ensure coffee authenticity.
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    The potential of certification for climate change mitigation in the agri-food sector : a case study of carbon neutral certified coffee from Costa Rica
    (2017) Birkenberg, Athena; Birner, Regina
    Advancing economic, social and environmental sustainability in the agri-food sector is increasingly pursued by various actors along global value chains. One option to address sustainability concerns is to use voluntary sustainability standards and certifications/labels as market-based governance tools for self-regulation. Recently, the demand for particular climate standards and labels has increased, however little is known about their potential and challenges. Individual aspects of such voluntary sustainability certifications have been investigated, such as the effectiveness and impact of certifications or the purchasing decisions of consumers. However, a holistic and interdisciplinary approach by considering the complete value chain is rare and, thus challenges are overlooked and proposed solutions remain limited in scope. Moreover, LCA-based certifications addressing climate change mitigation present a new field of research. Against this background, this thesis aims to elicit the challenges and potential of sustainability certification in the agri-food sector. Taking the case of the world’s first carbon neutral certified coffee, the complete chain – from standard development to consumer choices – has been examined. This coffee is produced by Coopedota, a Costa Rican cooperative of small-scale farmers, and exported to a family-run specialty coffee roaster, Hochland Kaffee Hunzelmann GmbH, in Germany. In the case under consideration, a newly released and highly prescriptive standard for carbon neutrality, the Publicly Available Specification (PAS) 2060, has been adopted since 2011. PAS 2060 is the first independent international standard for carbon neutrality that provides a common definition and a recognized method that is based on a life cycle assessment (LCA). To achieve carbon neutrality, the respective greenhouse gas (GHG) emissions are compiled, before continuous reduction activities are executed and the residual GHG emissions are offset by purchasing carbon credits. Costa Rica is relevant because it is actively pursuing carbon neutrality at the national level and the case of Coopedota serves as a pioneer in this field. In this thesis, an interdisciplinary case study approach is used to investigate in a holistic manner the challenges of carbon neutral certification in the agri-food sector. The study is guided by a conceptual framework developed from relevant literature on voluntary sustainability standards. The three specific objectives of the thesis are: (1) identify the success factors that made the carbon neutral certification in Coopedota possible and understanding the major challenges related to the standards implementation; (2) estimate the potential of on-farm carbon sequestration to compensate for the coffee carbon footprint and reduce carbon offsetting; and (3) estimate the willingness to pay for a carbon neutral label among German consumers of specialty coffee. This thesis contains three main chapters in addition to a general introduction and discussion. The first chapter addresses existing knowledge gaps regarding the role of social network dynamics, actor characteristics and linkages for successful pioneering in sustainable development, and investigates the challenges of implementing PAS 2060 by Coopedota. Qualitative research methods, such as in-depth interviews, participatory social network and process mapping as well as field observations were applied. The study found the prior achievements of the cooperative (e.g. compliance to ISO norms) and a ‘fertile ground’ in terms of ongoing climate change mitigation policies, as important factors for the successful implementation of the standard. Further success factors were a strong central and visionary actor and a diverse network of supporting actors from science, business and politics. The main challenges in implementing the carbon neutral certification were the acquirement of reliable farm data and the advertisement and communication of a carbon neutral label. The second chapter focuses on the problem that biogenic carbon sequestration is rarely considered in LCA-based standards. To estimate the annual potential of biogenic carbon accounting in coffee-agroforestry systems (CAFS) a literature review was conducted and the carbon sequestration based on a carbon inventory at the coffee farms was modeled. The results of a 20-year simulation show that on average, CAFS at Coopedota can compensate the carbon footprint of coffee by approximately 160% annually. Simultaneously, a trade-off between carbon sequestration and productivity at reduced inputs appears, which should be minimized. In the third chapter a marginal willingness to pay (WTP) of € 1.70 for a carbon neutral label was identified on a 250g package of specialty coffee by a discrete choice experiment among German consumers. Yet this marginal WTP was lower than the marginal WTP among the same consumers for direct trade claims or a Fair Trade certificate. Direct trade claims refer to the situation where direct trade relations exist; however, they are not certified and only declared by the retailer, as in the case of the family-run coffee roaster Hochland Kaffee Hunzelmann GmbH. Moreover, a positive synergistic effect was discovered for the combination of the carbon neutral label with direct trade claims. However, a public awareness on the contribution of agriculture to climate change is missing, as is the familiarity of the public with carbon concepts. Concluding, LCA-based certification for carbon neutrality can be a promising market-based tool for the agri-food sector to mitigate climate change. Such certification holds promise because it addresses recent demands for climate relevant information on agri-food products, while benefitting producers, the environment and consumers alike. Examples of these benefits include a potential increase in resource use efficiency, identification and minimization of GHG emission hot spots and trustworthiness among consumers due to the prescriptive nature of the standards. Additionally, the interdisciplinary case study approach enabled the identification of multi-faceted challenges and recommendations. One recommendation is that an agricultural perspective needs to be integrated into the standard by, for example, enabling the accounting of biogenic carbon sequestration. Such carbon accounting would prevent criticism of carbon offsetting and foster synergies between climate change mitigation, sustainability, and resilience. Particularly in the case of higher carbon prices, carbon accounting would be economically interesting but further research is needed to provide a robust dataset to enable it. Independent from a potential premium price for the label, access to capital and governmental support programs, especially for smallholders in less developed countries, can foster the implementation of greener technologies and allow stakeholders to benefit from increased efficiencies. The findings of this thesis indicate that coupling a carbon standard with existing sustainability standards, which use similar datasets, could ease the acquirement of reliable farm data on GHG emissions and reduce costs. Moreover, a coupling of standards could ensure additional sustainability practices, beyond the climate aspect, as already associated by consumers. This study also indicates that to establish markets for carbon neutral products, consumers first have to be aware of the extent of the agri-food sector’s contribution to climate change and consumer responsibility in tackling this problem through their purchasing behavior. This thesis further illustrates the importance of innovators in advancing development goals. Taking action on climate change mitigation and shaping a more sustainable agri-food sector requires strong initiatives and visionaries on the ground, as exemplified by the pioneering case of Coopedota.