Environmental aspects and economic evaluation of new green hydrolysis method for waste feather processing

Abstract

In recent years, an increase in the chicken meat process industry has been growing quickly, which brings a large amount of difficult to process waste, chicken feathers. These billions of kilograms create a serious waste problem over the world, furthermore, poultry feather processing is not only particularly difficult but also relatively expensive. In fact, there is no technology suitable for processing such huge quantities of feathers to guarantee sustainable development of the chicken meat industry together with processing of waste feathers. This article introduces a newly designed and original, highly efficient and environmentally friendly method of physicochemical hydrolysis of waste feathers. The hydrolysis is carried out in the presence of a weak organic carboxylic acid; thus, the resulting hydrolysate does not contain any salts or ashes. Therefore, a resulting hydrolysate, which includes a mixture of amino acids, peptides, proteins, glycoproteins and free fatty acids, is suitable for a variety of applications; e.g. as a chondroprotective agent in the treatment of joint diseases, nutrients for crop plants or targeted biostimulants for agriculture. This paper is focused not only on the process scale-up but also on environmental aspects and economic evaluations to bring general view of the process. Graphic abstract

Inactivation of indicator microorganisms and biological hazards by standard and/or alternative processing methods in Category 2 and 3 animal by‐products and derived products to be used as organic fertilisers and/or soil improvers

“…The yield of the hydrolytic processes depends on pH, temperature and reaction time, and also on the type and concentration of acid or base used. As a drawback, commonly applied hydrolysis leads to the requirement for subsequent recycling of the process solutions, including neutralisation and elimination of undesirable salts (Solcova et al., 2021 ). Treated in dimethyl sulfoxide or other solvents to get value added products from feather keratin, generated in excess from various livestock industries (Azmi et al., 2018 ).…”

“…The yield of the hydrolytic processes depends on pH, temperature and reaction time, and also on the type and concentration of acid or base used. As a drawback, commonly applied hydrolysis leads to the requirement for subsequent recycling of the process solutions, including neutralisation and elimination of undesirable salts (Solcova et al., 2021 ).…”

The Potential for Hydrolysed Sheep Wool as a Sustainable Source of Fertiliser for Irish Agriculture

“…Following a review of the literature, the economic returns associated with hydrolysis of sheep wool could not be found. Solcova et al [38] conducted an economic evaluation of using malic acid (a weak organic carboxylic acid) as a green hydrolysis method for the processing of waste chicken feathers in the Czech Republic. In this study, Solcova et al [38] used an 8000 L reactor to process 340 kg of feathers per batch.…”

“…Solcova et al [38] conducted an economic evaluation of using malic acid (a weak organic carboxylic acid) as a green hydrolysis method for the processing of waste chicken feathers in the Czech Republic. In this study, Solcova et al [38] used an 8000 L reactor to process 340 kg of feathers per batch. The total time to process a batch including the time required for the handling of the feathers and process material was 24 h. For this paper, the costs of hydrolysis reported by the Solcova et al [38] study (Table 5) were used to estimate the economic return from processing sheep wool in Ireland.…”

“…In this study, Solcova et al [38] used an 8000 L reactor to process 340 kg of feathers per batch. The total time to process a batch including the time required for the handling of the feathers and process material was 24 h. For this paper, the costs of hydrolysis reported by the Solcova et al [38] study (Table 5) were used to estimate the economic return from processing sheep wool in Ireland. If the feedstock, in this case sheep wool, can be achieved with zero associated costs, then the cost of processing a batch (340 kg) is €116.7.…”