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Introduction
The German online food trade is facing great challenges in order to sustain the demanding clientele. In addition to items of daily use, it is also important to bring fresh, chilled or frozen food quickly and safely to the customer. Especially deep-frozen products have been growing steady for years. With regard to the shipping business, frozen products are particularly good since they can be handled industrially and stored for longer periods than fresh foods. Enhanced manufacturing and freezing processes ensure higher qualities of the products, which now also meets higher requirements. The safe dispatch of deep-frozen foods requires compliance with hygienic standards, in particular, the adherence to the cold chain. In addition to stationary trading, frozen foods are delivered by direct distributors for decades by means of special deep-freeze vehicles. However, for some time now, competitors have been operating the classic online business as a full-range vendor and they are relying on the delivery of frozen products by means of standard CEP (Courier Express Parcels) service providers. In a comparative analysis, the present paper investigates the environmental sustainability of alternative shipping form using a Life Cycle Assessment according to DIN EN ISO 14040.
According to a study by the German Frozen Food Institute more than 3.5 million tons of frozen foods were sold in Germany in 2015, which corresponds to an approximate per capita consumption of more than 43 kilograms and sales plus of 3.7 % compared to the previous year \citep{tiefkuehlinistitut}. In addition to ready-made meals such as pizza and buns, there are also vegetables, fish or meat. Environmental sustainability is one issue in the context of consuming frozen foods since it is an indicator of how products or activities affect protective goods, such as soil, water, air or climate \citep{Umweltdatenbank}. The answer to this issue is of crucial importance since more and more people see the environmental sustainability of organic foods as a major factor for purchasing \citep{Bundesvereinigung}. The ECO-Institute Freiburg provides a comparative analysis of five selected foods and concludes that frozen products are not more climate-damaging than fresh products when all production and distribution stages are taken into account \citep{Öko-Insitut}. Compared to the fresh products, the industrial processing process results significantly less climate-costly than the case of storage and individual household preparation. Due to the more complex distribution of frozen foods, this consideration is equalized but under certain assumptions it can lead to the statement that frozen products are not more climate-damaging than fresh produce. This consideration is based on a customer’s purchase in the supermarket. However, it can be observed that the online food trade is gaining in importance in comparison to stationary retail. In his study for the ‘Groceries Forum 2015’ in Bremerhaven Professor Seeck mentions essentially three possibilities for logistics networks in e-commerce \citep{Seeck}. Pure online players with central warehouse delivery, where deliveries are made from agglomeration-related central warehouse locations. To this pure online business also mixed forms from online and stationary trade are conceivable. Thus, the stationary trade can also offer an online sale, in which the customers are supplied from local branches. REWE is one of the German supermarket chains that uses this type of delivery. As alternative online sales and stationary trading may also be consolidated with agglomeration-related “online branches” where the delivery takes place as in stationary trading. In addition, it has to be decided whether the delivery is to take place through an own delivery organization or whether a Courier, Express and Parcel service providers are used. For all considerations it must be taken into account that the dispatch of foodstuffs and in particular of fresh and frozen foods imposes special requirements on transport. In particular, this concerns compliance with temperature corridors and hygiene regulations. In addition to fast and safe delivery, ecological aspects are also of great importance to the consumers. Especially for organic food, it should be ensured that the ecological footprint is not impaired by expensive transports, as for example additional transports in low-wage countries for further processing. The distribution of frozen food as a section of the entire supply chain has several potentials for improvement, such as the design of the cold chain infrastructure \citep{Manzini_2013}. Particularly the transport costs with heavy-goods-vehicles (HGV) and the accumulating packaging materials have to be analyzed critically, as these two aspects have the greatest impact potential on environmental sustainability \citep{Hoang_2016}. One of the most relevant packaging material for frozen food delivery is Expanded Polystyrene (EPS), also known as Styrofoam, which requires thick sections to insulate the products and keep them at the desired temperature for longer periods. However, thicker packaging leads to bulky boxes. In the business-to-business sector, industrial disposal systems are available. For private costumers storage and disposal from EPS-Packaging is cumbersome. According to a study on online food commerce, packaging plays an important role since 36% of the online shoppers would buy groceries regularly online if they are sent using environmentally friendly packaging and few packaging waste \citep{Fingerhut}. In order to reduce the waste volume of EPS-packaging, it is necessary to break it, which might be a challenging task for some customers.