Recovering Apple Agro-Industrial Waste for Bioethanol and Vinasse Joint Production: Screening the Potential of Chile

Abstract

Bioethanol production has increased in demand as a replacement for conventional fuels. This work studies the use of apple pomace, which corresponds to 45% (w/w) of dehydrated apple production, as a reliable and inexpensive source for bioethanol production. Additionally, the vinasse obtained from the process as a byproduct is analyzed. Apple pomace has important properties for energy purposes, with high soluble sugar (6%–8%), organic compounds and low protein content. The carbohydrates were consumed in 99.3% in 144 h at a temperature of 30 °C and in a yeast Saccharomyces cerevisiae (YSC) concentration of 0.10 g/L. The bioethanol purity produced, 99.5% (v/v), was quantified by gas chromatography and calorific value (23.21 MJ/kg). This high purity, which fulfills the EN 15376, ASTM D 4806 Standard, allows its use as a fuel and oil additive. Moreover, it can be stated that vinasse obtained from alcohol distillation is a compound that has physicochemical values like other vinasses. Finally, Chile, as the most important exporting country of dehydrated apples in the world, has great potential to take advantage of the use of this raw material for bioethanol and vinasse production.

Thermal Treatment to Obtain 5-Hydroxymethyl Furfural (5-HMF), Furfural and Phenolic Compounds from Vinasse Waste from Agave

“…For original vinasse (OV), the high value of COD is similar to that reported by other authors in tequila vinasses, with concentrations ranging between 28 and 45 g/L [ 21 ]. Similar data were reported by Hernández et al [ 22 ] in vinasses extracted from sugarcane (30.4 g/L) but lower than that found in cane molasses (95 g/L), wine (50.2 g/L), and sorghum (79.9 g/L). The high content of sugars and phenolic compounds will be discussed later.…”

Apple Pomace as an Alternative Substrate for Butanol Production

“…AP can also be used as an alternative substrate (Ampese et al, 2023). Pomace contain soluble sugars and structural carbohydrates, which makes them a promising substrate for further research on biobutanol technology (Hernandes et al, 2021). The aim of this work was to study the possibility of using AP as a substrate by domestic butanol-producing strains of Clostridium sp.…”

Evolution of physico-chemical parameters, microorganism diversity and volatile organic compound of apple pomace exposed to ambient conditions

“…Apple pomace corresponds to 45% of the apple manufacturing process and consists of remains of pulp (54%), cores (4%), peel (34%) and seeds (7%) [ 1 ]. This waste is obtained mainly from the production of apple pulp and juice, and dehydrated apple [ 2 ]. In Chile, 1.6 million tons of this residue are produced annually, which is mainly made up of sugars, cellulose, fibers, pectin and antioxidants, among others [ 3 ].…”

“…In Chile, 1.6 million tons of this residue are produced annually, which is mainly made up of sugars, cellulose, fibers, pectin and antioxidants, among others [ 3 ]. The sugars and nutrients of apple pomace have been used as raw material to generate by-products of interest such as bioethanol, biopolymer, phenolic antioxidants, citric and lactic acid, enzymes, aromatic compounds, among others [ 2 , [4] , [5] , [6] ]. However, fresh apple pomace is perishable and highly biodegradable, given its high organic matter content, which on a large scale can cause considerable environmental pollution [ 4 ].…”

“…This waste is often neglected and stored in open-air conditions on agricultural estates or dedicated storage areas. The purpose of storage is to reduce its moisture content and volume so that it can be reprocessed later for different uses, especially bioproducts [ 2 ]. The accumulation of apple pomace generates emissions of VOCs especially as a result of natural fermentative processes occurring over time.…”