This study was conducted to investigate the growth of microorganisms, including pathogenic bacteria such as Cronobacter sakazakii and Bacillus cereus, in Sunsik beverages made of water, milk, soymilk, or honey-water during storage at room temperature. Prepared Sunsik beverages were stored at room temperature and the growth of total aerobic counts, Escherichia coli/coliforms, and yeast and mold were measured. Also, samples inoculated with a cocktail of C. sakazakii or B. cereus spores were stored at room temperature and their growths were determined during storage. Populations of total aerobic counts and coliforms significantly increased with increasing storage time at room temperature, which resulted in higher than 8 log and 7 log after 24 h in all samples except for the honey-water sample, respectively. Levels of total aerobic counts and coliforms were significantly lower in the honey-water sample than in the other samples after 6 and 9 h of storage, respectively. Initial populations of C. sakazakii and B. cereus ranged from 0 to 1 log CFU/mL, respectively, and these populations significantly increased with increasing storage time at room temperature. Therefore, populations of C. sakazakii and B. cereus were approximately 7 to 8 log CFU/mL after 24 h of storage. However, after 12 and 9 h of storage, there were significant differences in levels of C. sakazakii and B. cereus between the honey-water sample and the other samples, respectively. Based on these results, the addition of honey can inhibit microbial growth in Sunsik beverages; however, the best way to avoid pathogen infection would be to consume Sunsik beverages as soon as possible after preparation.

South Korea’s food self-sufficiency ratio (SSR) dramatically decreased from 56 % in 1980 to 27 % in 2010, due to changes in food production and consumption patterns. Naturally, the changes in food self-sufficiency and consumption patterns will affect the world agricultural trade. This study aims to analyze trends in water footprints (WFs) on the basis of statistics for per capita food consumption in the last 25 years. The WFs for potential water requirements (WFsPWR) were estimated using food production and consumption scenarios for the targets of the SSRs in 2015 and 2020. The WFs for per capita food consumption (WFscₐₚ) were estimated at 512.9 m³ (1985) and 822.9 m³ (2010). Cereals and meats accounted for 36.3 and 21.5 % of the total WFscₐₚ in 1985, and 18.3 and 38.6 % in 2010, respectively. This implies that with economic development, Korea’s dietary patterns have changed from cereal to meat-oriented. To achieve the targets of 52 % (2015) and 55 % (2020) food SSR based on calories, additional WFsPWR are estimated to be 1255.5 Mm³ (2015) and 1923.9 Mm³ (2020). Results of this study are expected to be a useful basis for making long-term policies for sustainable agricultural production and water management from technical and social perspectives.

Exploring the environmental impact of dietary consumption has become increasingly important to understand the carbon-water-food nexus, vital to achieving UN sustainable development goals. However, the research on diet-based nexus assessment is still lacking. Here, we developed an Environmentally Extended Multi-Regional Input-Output (EE-MRIO) model with compiling a global MRIO table based on the latest Global Trade Analysis Project (GTAP) 10 database, where we specifically constructed a water withdrawal account and matched it to each economy at the sectoral level. The regional heterogeneity and synergy of carbon-water nexus affected by dietary patterns in nine countries was explored. The results show that: (1) Dietary consumption is the main use of water withdrawal for each country; Japan, the US, South Korea, and India have a high per capita dietary water footprint. Mainly due to consumption of processed rice, Japan has the highest per capita value of 488 M³/year, accounting for 63.4% of the total water footprint. (2) The total dietary carbon footprints in China, India, and the US are high, which is mainly caused by the high consumption of animal products (including dairy) either due to the large population (China, India) or animal-based diet (the US). Americans have the highest per capita dietary carbon footprint, reaching 755.4 kg/year, 2.76 times that of the global average. (3) Generally, imported/foreign footprints account for a greater share in dietary water and carbon footprints of developed countries with an animal-based diet. (4) In the nexus analysis, the US, Japan, and South Korea are key-nexus countries, vegetables, fruit and nuts, tobacco and beverages, and other food products are selected as key-nexus sectors with relatively high dietary water and carbon footprint. Furthermore, dietary consumption choices lead to different environmental impacts. It is particularly important to find a sustainable dietary route adapted to each country considering that heterogeneity and synergism exist in key-nexus sectors to achieve the relevant Sustainable Development Goals.

This study presents a comprehensive decision model for the integrative design of a biorefinery for bioethanol production and its supply chain (BPSC) under the water-energy-food-land (WEFL) nexus framework. A new optimization model was developed using a mixed integer linear programming to simultaneously identify the optimal process configuration of a bioethanol production plant and the optimal bioethanol supply network. The objective function of the model is to minimize the total annual cost for establishing and operating the BPSC to meet society’s needs (energy, water and food) under the limited resources and land availabilities, and technology capacity. The proposed model can provide the optimal solutions for design and operation of the BPSC: i) the types, and quantities of feedstocks; ii) types, number, and location of facilities and; iii) regional flows. The capability of the proposed model was validated through the case study of Jeju Island, Korea, with two scenarios: BPSC by cost (COPT) and nexus (NOPT) optimization. As a result, it was identified that the BPSC in NOPT requires higher energy supply cost (8.55 B$) than the COPT (6.44 B$). However, the BPSC in NOPT can satisfy the society demands with relatively smaller consumption of occupied land (2%), fresh water (30%) and primary energy consumption (64%) than that of the COPT, respectively.

Population and economic growth pose unique challenges in securing sufficient water, energy, and food to meet demand at the sub-national (regional), national, and supra-national level. An increasing share of this demand is met through trade and imports. The unprecedented rapid growth, extent, and complexity of global value chains (GVCs) since the 1980s have reshaped global trade. The GVCs – and new economic patterns of regionalization – affect the demands on water, energy, and food within countries and across global supply chains. East Asia is of particular interest due to the region’s rapid economic growth, substantial population size, high interdependence of the region’s economies, and varying degree of resource availability. While greater interdependence across the region has increased the efficiency of production and trade, these activities require the input of water-energy-food and generate disturbances in the environment. The transnational inter-regional input-output approach is utilized in a tele-connected Water-Energy-Food Nexus (WEFN) analysis of the East Asia GVC to assess competing demands for these resources and environmental outcomes.This analysis demonstrates the hidden virtual flows of water, energy, and food embodied in intra-regional and transnational inter-regional trade. China’s current national export oriented economic growth strategy in East Asia is not sustainable from the WEFN perspective. China is a net virtual exporter of nexus resources to Japan and South Korea. China’s prioritization of economic growth and trade in low value added and pollution intensive sectors consumes a great amount of nexus resources within its territory to satisfy consumers’ demands in Japan and South Korea. Japan’s Kanto and Kinki regions and South Korea’s Sudokwon region were the major beneficiaries while China bore the environmental burden associated with the production of exports. For example, net virtual exports from China’s East region included over 1.2billionm³ of scarce water and 61.3million metric (CO₂ equivalent) tons of greenhouse gases (i.e. CO₂, NH₄, and N₂O) and 2 million metric tons of SOₓ emissions.Trade is an important mechanism for overcoming resource bottlenecks, but, taking into account environmental linkages, regional specialization is not necessarily mutually beneficial. This analysis demonstrates a mismatch between regional water-energy-food availability and final resource consumption and the lack of attention for environmental impacts in national economic growth strategies. Resource scarce countries like China must, therefore, incorporate trade-off decisions between pursuing national economic growth, incurring environmental degradation, and food security into strategic regional development policies.