| Literature DB >> 35434720 |
Nilanthi Jayathilake1, Mohamed Aheeyar1, Pay Drechsel1.
Abstract
Using farm animals for their natural capability of "recycling" food waste (FW) that is unfit for direct human consumption can support a circular economy as shown in the case of Sri Lanka's Western Province. The reuse of organic residues including FW as animal feed is a traditional agricultural practice in Sri Lanka but is less studied within an urban FW context. A survey of piggeries using FW in and around the rapidly urbanizing city of Colombo showed that FW is a major feed source in the farms accounting for on average 82% of total feed. About 40% of the farms collected the FW mainly from hotels, restaurants, and institutional canteens. Urban FW is supplied to farmers free of charge when collected directly from the sources, although 26% of the farmers collected FW via intermediaries against a fee. As FW is collected daily, the restaurants appreciate the reliable service, the farmers the low-cost feed, and the municipality the reduced FW volumes to be collected. However, this triple-win situation encounters challenges such as (tourist related) seasonal low supply, which was exacerbated under the Covid-19 lockdown of food services. Another area of concern refers to biosafety. Although the large majority of interviewed farmers boil FW which contains raw meat or fish, there is a paucity of related guidelines and control. Given the benefits of FW use, it is worthwhile to explore how far these informal partnerships could be scaled without increasing transport costs for farmers, while introducing biosafety monitoring. For now, the regulatory environment is highly siloed and does not support material transitions across sector boundaries towards a circular economy.Entities:
Keywords: Circular economy; Food security; Piggeries; Regulations; Reuse; Urban food waste
Year: 2022 PMID: 35434720 PMCID: PMC9002037 DOI: 10.1007/s43615-022-00168-8
Source DB: PubMed Journal: Circ Econ Sustain ISSN: 2730-597X
Fig. 1Pig population and pork production in Sri Lanka (2011–2020). Data
source: Department of Animal Production and Health, Sri Lanka1
Estimated amount of FW in the SW generated in selected highly populated municipalities in Sri Lanka
| Municipal council | Population (2022) | Total SW quantity (tonnes/day) | FW quantities (tonnes/day) | FW percentage | References |
|---|---|---|---|---|---|
| Colombo | 648,034 | 706 | 353 | 50% | [ |
| Moratuwa | 185,031 | 125 | 65 | 52% | [ |
| Jaffna | 169,102 | 105 | 72 | 69% | [ |
| Kandy | 111,701 | 127 | 74 | 58% | [ |
| Batticaloa | 86,742 | 53 | 30 | 57% | [ |
| Kurunegala | 28,571 | 48 | 25 | 52% | [ |
Source: [9], population estimates from https://worldpopulationreview.com/countries/cities/sri-lanka
Fig. 2Number of pigs in surveyed piggeries.
Source: Authors’ survey data in 2020
Classification of sample swine farms (based on the number of adult animals per farm)
| Scale | Number of farms |
|---|---|
| Domestic scale (1–4 adult animals) | 1 |
| Small scale (5–25 adult animals) | 7 |
| Medium scale (26–49 adult animals) | 1 |
| Large scale (> 50 adult animals) | 15 |
Source: Authors’ survey data in 2020; classification scale by [36]
Fig. 3Average amount of FW collected by pig farmers (kg/day).
Source: Authors’ survey data in 2020
Results of 7-day audits of food waste generation in Colombo in 2020
| Type of case study | Origin of FW | Method of assessment | Key findings |
|---|---|---|---|
| Food service | Hotel | A 7-day FW audit was conducted in one top-end hotel located in Colombo (with several banquet halls and restaurants able for catering to over 4,000 guests in peak periods) | The hotel generated 2.4 tonnes of FW during the week of which more than 2/3 was edible at the time of discard Edible FW consisted of 88% of cooked rice, starchy foods, vegetables, and fruits and 12% of fish and meat |
| Restaurant | A 7-day FW audit was conducted at 5 selected restaurants in a food court in Colombo | The selected restaurants generated 126 kg of FW in the week out of which about 70% was edible. The edible FW mainly consisted of rice (47% of total FW) and vegetables (22% of total FW) | |
| Retail and wholesale market | Wholesale market | A 7-day FW audit was conducted at two vegetable shops, two fruit shops, and two meat shops in the market in Colombo | 740 kg of FW generated in the selected fruit and vegetable shops in the week. About 46% of the FW was edible |
| Retail market | A 7-day FW audit was done at two vegetable stalls, two fruit stalls, one fish stall, one meat stall, and one dry fish stall located in the retail market in Colombo | The FW generated in the stalls amounted to 2 tonnes during the week About 80% of the FW was vegetables and fruit and 90% of the vegetable waste was edible | |
| Vegetable and fruit retail stall | A 7-day FW audit was conducted at a retail stall in Colombo | The stall generated 327 kg of FW during the week. About 65–85% of FW generated in the stall was edible | |
| Supermarket | A 7-day FW audit was conducted at an outlet of a popular supermarket chain in Colombo | Total FW generated in the week was 445 kg. Vegetable waste was highest (48%) followed by fruits (24%) and cooked rice and starchy products (25%) About 84% of the FW was edible | |
| Caterers | Hospital | A 7-day FW audit was conducted in two selected hospital wards and the hospital kitchen | FW generated in the selected two wards, hospital kitchen and staff dining area was 493 kg in the week. About 65% of the FW was edible |
| Households | Middle-income households | A 7-day FW audit was conducted in 5 middle- income households in Colombo | Total FW generated by the 5 households was 137 kg; 41% of FW was edible with 60% of edible waste being rice |
| Low-income households | A 7-day FW audit was conducted in 5 low-income households in Colombo | Total FW generated by the 5 households was 92 kg; 50% of FW was edible with 55% of edible waste being rice |
Source: [37]