**1. Introduction**

Growing concern about circular bioeconomy, hunger, resource conservation, and sustainable development associated with food loss and waste (FLW) has raised public awareness in recent years [1,2]. With t he changes in diet habits and the improvement of living standards, many food waste has been generated from residential, commercial, and institutional sources, such as retails, wholesales, restaurants, hospitals, schools, and hotels, as well as from industrial sources like food processing plants, animal-breeding farms, crop/vegetable/fruit farms, and employee lunchrooms [3,4]. The discarded food often contained vegetable leaves, leftover meals and grains, fruit peelings, dairy, oils/grease, salts, and water. Due to its constituents like lignocelluloses, protein, and oils and grease, such wastes without valorization for the production of value-added materials and/or bioenergy would imply the resource depletion and wastage. Moreover, the environmental concern could be derived from their compositions, which may cause negative effects on the environment (e.g., odors, vectors, emission gas emissions, or climate change) if they are illegally disposed of in dumping sites or fields [5]. In addition, these food discards may be rich in the moisture and nutrient compositions, thus causing wastewater discharge with high biochemical oxygen demand (BOD) and/or chemical oxygen demand (COD) values in the landfill leachate [6]. For these reasons, the valorization of food waste has become increasingly important in recent years due to the United Nations (UN) Sustainable Development Goals (SDGs) and national regulatory requirements [7]. Therefore, the reuse

**Citation:** Tsai, W.-T.; Lin, Y.-Q. Analysis of Promotion Policies for the Valorization of Food Waste from Industrial Sources in Taiwan. *Fermentation* **2021**, *7*, 51. https:// doi.org/10.3390/fermentation7020051

Academic Editor: Alessia Tropea

Received: 1 March 2021 Accepted: 1 April 2021 Published: 5 April 2021

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**Copyright:** © 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/).

of food waste as a valuable resource for the production of materials, fertilizer, and biofuels has been reviewed recently [7,8].

As mentioned above, FLW has become one of vital issues raised by great public concern. In order to provide a target-oriented blueprint for peace and prosperity to all countries in the near future (2030), the United Nations (UN) announced 17 Sustainable SDGs on 25 December 2015 [9], reflecting the increased global awareness for the environmental issues. In this regards, the Target 12.3 of the SDGs, thus, calls for halving per capita global food waste at retail and consumer levels by 2030, as well as reducing food losses along the production and supply chains. In line with the international trends, the Taiwan government announced the Taiwan's Sustainable Development Goals in July 2019 [10], including the goals for 2030 and targets for 2020. Regarding FLW, the 12th Goal is "Responsible Consumption and Production", which involves the Goal 12.3 by reducing food lose in the supply-chain side and also reducing food wastage in the consumer side, and the Goal 12.4 by reducing (food) waste generation through green production and also promoting (food) waste valorization and its technological capacity. In addition, the 7th and 13th Goals in the Taiwan's SDGs aims at taking actions for providing renewable energy and combating climate change, respectively, which were also relevant to the food waste issue.

According to the official definition in Taiwan, waste can be categorized into general (urban) waste and industrial waste. Under the circular economy principle, the central governing agency (i.e., Environmental Protection Administration, EPA) in Taiwan has implemented the Four-in-One Resource Recycling Plan over the past two decades [11,12], which combined the efforts by communities, recycling enterprises, local governments, and the Recycling Fund. It showed that the urban waste recycling rate has increased from about 10% in 2000 to over 56% in 2019 [13]. Regarding the kitchen waste (including waste cooking oil) management, the Taiwan EPA promulgated the regulations of governing the valorization of food waste from non-industrial (urban) and industrial sources by designating it as a mandatory recyclable waste under the authorization of the Waste Management Act (WMA) [14,15]. Furthermore, over ten items of food waste valorization (or reuse) from industrial sources have defined by the central responsible agencies under the authorization of the WMA, including the Council of Agriculture (COA), Ministry of Finance (MOF), and Ministry of Economic Affairs (MOEA) [16]. Currently, most of the industrial food waste items were reused as valuable feedstocks for animal feed, organic fertilizer, or biomass energy. Meanwhile, the EPA also provided the subsidies for local governments to establish their valorization (animal feed) programs for the prevention of African swine fever (ASF) spread because the virus can persist in the kitchen waste without high- temperature (>90 ◦C) cooking [15]. Moreover, the burden on municipal solid waste (MSW) incineration plants and sanitary landfills can be reduced in recent years [15].

Regarding the regulatory and promotional measures for mandatory valorization of food waste from the industrial sources, few studies were discussed previously [4,17]. Mirabella et al. [4] reviewed the valuable compounds and fuels derived from the solid and liquid waste in the food processing industry but lacked the promotion policies or regulatory measures for the food waste valorization. Naziri et al. [17] reported the valorization of the major agrifood (i.e., olive oil, wine, and rice) industrial by-products and waste from Central Macedonia in Greece for the recovery of value-added compounds (e.g., antioxidants) for food applications. As compared to other countries [18,19], the food waste valorization with high recycling rate in Taiwan may be a learnable case due to the adaptation of "zero waste and resource recycling" policy. In the previous studies [15,20], the author focused on the regulatory and promotion measures for the valorization of food waste from the non-industrial sources like residential and service sectors. Therefore, the present study will put emphasis on the promotion policies and regulatory measures for the valorization of food waste from industrial sources (hereinafter industrial food waste) in Taiwan. Therefore, the aim of this study was twofold. First, the updated data on the statistics and status of industrial food waste generation and treatment in Taiwan will be addressed in Section 3.1 to analyze the trends. Second, the promotion policies and regulatory measures for industrial

food waste valorization were studied subsequently based on the joint-efforts by the central governing authorities under the authorization of the WMA. In addition, a case study was addressed to highlight the environmental and economic benefits regarding the valorization of urban food waste for the production of bioenergy by anaerobic digestion in Taiwan.
