Dried-bakery waste as a substrate for n-caproate and n-caprylate production via chain elongation


Ntihuga J., Usack J. G., Mayer R., Kinbokun A. A., Yeşil H., Zhou M., ...Daha Fazla

Waste Management, cilt.216, ss.1-11, 2026 (SCI-Expanded)

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 216
  • Basım Tarihi: 2026
  • Doi Numarası: 10.1016/j.wasman.2026.115454
  • Dergi Adı: Waste Management
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED)
  • Sayfa Sayıları: ss.1-11
  • Marmara Üniversitesi Adresli: Evet

Özet

Bakery waste is a promising feedstock for the circular economy; however, its use for producing medium-chain carboxylates (MCCs) via microbial chain elongation remains unexplored. This study investigated pretreatment, pertraction, and chain elongation strategies to convert bakery waste into n-caproate and n-caprylate. Bakery waste was mechanically and enzymatically processed, and different inocula were tested to optimize the conversion of the resulting glucose-rich solution into lactate and ethanol (intermediates). These intermediates were fed into continuous chain-elongation systems that operated for over 386 days at 37°C and pH 5.5. Results showed that 30–35% of bakery waste carbon was converted into n-caproate and 10–15% into n-caprylate. Enzymatic starch hydrolysis proved essential, and lactate was a superior intermediate for chain elongation compared to ethanol. A maximum volumetric MCC production rate of 131 mmol C L1 d1 (0.1 g L1h−1) was achieved. This integrated approach demonstrates an efficient pathway for valorizing bakery waste.