The non-nutritional performance characteristics of peptones made from rendered protein

Abstract

Economic considerations require the use of inexpensive feedstocks for the fermentative production of moderate-value products. Our previous work has shown that peptones capable of supporting the growth of various microorganisms can be produced from inexpensive animal proteins, including meat and bone meal, feather meal, and blood meal, through alkaline or enzymatic hydrolysis. In this work, we explore how these experimental peptones compare to commercial peptones in terms of performance characteristics other than chemical make-up; these characteristics can impact fermentation operating cost. It is shown that experimental peptone powders produced through enzymatic hydrolysis are highly hygroscopic and that their physical form is not stable to humid storage conditions; those produced through alkaline hydrolysis and commercial peptones are less hygroscopic. When used in growth medium, all peptones contribute haze to the solution; experiments show that the source of haze is different when using enzyme- versus alkali-hydrolyzed peptones. Alkali-hydrolyzed peptones and all peptones made from blood meal are stronger promoters of media foaming than the commercial peptones; some enzyme-hydrolyzed peptones support very little foam formation and are superior to the commercial peptones in this sense. Alkali-hydrolyzed peptones are roughly equivalent to commercial peptones in the coloration they contribute to media, while enzyme-hydrolyzed peptones contribute intense coloration to media. No peptone caused a significant change in the viscosity of media. The experimental peptones studied here may be acceptable low-cost substitutes for commercial peptones, but none is equivalent to the commercial products in all respects.

Valorization of rendering industry wastes and co-products for industrial chemicals, materials and energy: review

“…For example, peptones produced through enzymatic and alkaline hydrolysis of rendered animal protein including blood meal, meat and bone meal and feather meal to support the growth of microorganisms has been evaluated by Garcia et al (Garcia et al, 2010). Small peptides and amino acids have also been used as foliar fertilizers (Quartieri et al, 2002).…”

Hydrolysis of Animal Protein Meals for Improved Utility in Non-Feed Applications

“…Clearly, the success of this strategy was limited. Further experimentation, reported elsewhere (Garcia et al, 2010), confirmed that approximately half of residual ash in solution consisted of calcium salts. Possibly, calcium that precipitated as calcium carbonate re-solubilized as calcium bicarbonate when the solution was neutralized.…”

“…The hydrolysates have also been tested as feedstocks for industrial fermentations, substituting for expensive ingredients such as yeast extract or casamino acids. They were found to have favorable performance characteristics for this application (Garcia et al, 2010), and support the growth of the bacterium E. coli, the fungus Pythium irregular, and the alga Schizochytrium limacinum, in valuable-product-producing fermentation systems (manuscripts in preparation). The unhydrolyzed rendered meals are not effective in these applications.…”

Nonfeed Application of Rendered Animal Proteins for Microbial Production of Eicosapentaenoic Acid by the Fungus Pythium irregulare

“…3 The non-nutritional characteristics of the protein hydrolysates, such as hygroscopicity, chromicity, autoclave stability, viscosity, and foaming, were also reported; it is indicated that rendered proteins hydrolysate can be used as a low-cost substitute for commercial peptone. 4 All of these results demonstrate an opportunity for exploring animal proteins as a low-cost nutrition source for microorganism fermentation. This is particularly attractive for industrial fermentation focusing on commodity and moderatevalue products, as this type of fermentation process is characterized by a larger volume and being of moderate product value and more sensitive to the cost of growth medium ingredients.…”