Development and analysis of microbial characteristics of an acidulocomposting system for the treatment of garbage and cattle manure

Ammonia assimilation is key for the preservation of nitrogen during industrial-scale composting of chicken manure

Nitrogen loss from compost is a serious concern, causing severe environmental pollution. The NH4+-N content reflects the release of NH3. However, the nitrogen conversion pathway that has the greatest impact on NH4+-N content is still unclear. This study attempted to explore the key pathways, core functional microorganisms, and mechanisms involved in the transformation of ammonia nitrogen during composting. KEGG (Kyoto Encyclopedia of Genes and Genomes) metabolic pathways revealed that ammonia assimilation was dominated by the glutamate dehydrogenase (GDH) pathway (53.4%), which is crucial for nitrogen preservation. The combined analysis of KEGG, NR species annotation, and co-occurrence network identified 20 easy-to-regulate obligate core nitrogen-transforming functional microorganisms, including 18 ammonia-assimilating bacteria. Furthermore, the effects of environmental parameters on the obligate core functional microorganisms were investigated. The present study results provided a theoretical basis for the utilization of ten ammonia-assimilating bacteria, such as Paenibacillus, Erysipelatoclostridium, and Defluviimonas to improve the quality of compost.

Dynamics of Microbial Community during the Co-Composting of Swine and Poultry Manure with Spent Mushroom Substrates at an Industrial Scale

Spent mushroom substrates (SMSs) can be developed as a biofertilizer through composting. Here, we investigated the dynamics of bacterial and fungal communities during commercial composting and the effect of swine and poultry manure on their communities through MiSeq pyrosequencing. Weissella paramesenteroides and Lactobacillus helveticus were dominant bacterial species in the composts with soy waste (SMS-SW), whereas Thermotogaceae sp. and Ureibacillus sp. were dominant in the composts with swine and poultry manure (SMS-PM). For the fungal community, Flammulina velutipes was dominant in SMS-SW, whereas Trichosporon asahii, Candida catenulate, Aspergillus fumigatus, and Candida tropicalis were dominant in SMS-PM. The addition of manure affected the bacterial community significantly. Redundancy analysis indicated that bacterial communities were affected by temperature, potassium, and potassium oxide and fungal communities by temperature, Kjeldahl nitrogen, organic matter, and ammonium nitrogen. Our findings can guide future research on composting microbiology.

Fallen leaves are superior to tree pruning as bulking agents in aerobic composting disposing kitchen waste

Though aerobic composting has been frequently applied to kitchen waste disposal, appropriate bulking agents are essential to acquire a promising performance. Fallen leaves and tree pruning in urbans face huge disposal demands and have great potentials as bulking agents of aerobic composting while have been seldom examined yet. This study comparably explored the performance of fallen leaves bulked and tree pruning bulked aerobic composting disposing kitchen waste. Results indicated that though both reactors were effective in degrading kitchen waste, leaf bulked composting was superior to tree pruning bulked composting in terms of longer thermophilic period and higher maximum temperature, higher organics degradation efficiency, higher humification and less odorous gas emission. Bacterial community was a driving mechanism for above results. This study shows that fallen leaves bulked aerobic composting has great potentials for kitchen waste disposal.

Research on microbial structures, functions and metabolic pathways in an advanced denitrification system coupled with aerobic methane oxidation based on metagenomics

Methanotrophs can oxidize methane as the sole carbon and energy, and the resulting intermediate products can be simultaneously utilized by coexistent denitrifying bacteria to remove the nitrogen, which named Aerobic Methane Oxidation Coupled to Denitrification (AME-D). In this paper, an AME-D system was built in an improved denitrification bio-filter, to analyze the nitrogen removal efficiency and mechanism. The maximum TN removal rate reached 95.05%. As shown in Raman spectroscopy, in the effluent wave crests generated by the symmetric expansion and contraction of NO₃^- disappeared, and the distortion of olefin CH₂ and C-OH stretching of alcohols appeared. Metagenomics revealed Methylotenera and Methylobacter were the dominated methanotrophs. There was a completed methane and nitrogen metabolism pathway with the synergism of nxrAB, narGHI, nasAB, pmo-amoABC and mmo genes. Dissimilatory reduction pathway was the primary nitrate removal pathway. Moreover, Bradyrhizobium could participate in methane and nitrogen metabolism simultaneously.

The potential environmental risks of the utilization of composts from household food waste

Modern technologies (especially with the help of autonomous measurement and control systems) introduced automatic composters for the disposal of household food waste production. Environmental risks connected with the utilization of these composts can be characterized by the high electrical conductivity caused by a presence of sodium chloride in food. Electrical conductivity influences the ecotoxicity of the composts. The presence of pesticides in composted food also represents an important environmental problem. The following pesticides were found in compost samples from household food waste: 1,3,5-triazine, methyl trithion, bifenthrin, bifenox, carbophenothion, pirimicarb, dioxacarb, desmetryn. Pesticide content in composts varied from 0.3 to 16.3 μg/kg, the average value being 30.4 ± 10.1 μg/kg dry matter. The higher decomposition was found of "modern" pesticides in the composters. The removal of salts can ensure that inhibition will be < 30% while washing with the ratio of 1:3 will result in the inhibition < 5%. However, this way of processing is not effective for other organisms-Poecilia reticulata (mortality 100%) and Daphnia magna (immobilisation 100%) using this procedure as well as washing of the compost in the ratio 3:1.

Metagenomic analysis revealed the succession of microbiota and metabolic function in corncob composting for preparation of cultivation medium for Pleurotus ostreatus

Metagenomic sequencing was used to reveal the dynamic changes in microbiota and the metabolic functions in corncob composting for preparing cultivation medium of Pleurotus ostreatus. Results showed that the changes of physicochemical properties lead to different dominant phylum at different stages of composting. Firmicutes replaced Proteobacteria as the dominant phylum at thermophilic stage. Correlation analysis indicated that the succession of microbiota was significantly affected by the C/N ratio, pH, temperature and organic matters in compost. The changes in community inevitably lead to the differences of metabolic functions. Metabolism analysis indicated that carbohydrate, lipid and amino acid metabolism were relatively higher in thermophilic stage. Conversely, the metabolism of starch, sucrose, galactose, ascorbate was mainly detected in the late stage. The metabolisms of different stages were driven by different microorganisms. Overall, these findings deepened our understanding of metabolic functions, and it is of great value to the metabolomics research of composting system.

Effect of Cornstalk Biochar Immobilized Bacteria on Ammonia Reduction in Laying Hen Manure Composting

NH₃ emission has become one of the key factors for aerobic composting of animal manure. It has been reported that adding microbial agents during aerobic composting can reduce NH₃ emissions. However, environmental factors have a considerable influence on the activity and stability of the microbial agent. Therefore, this study used cornstalk biochar as carriers to find out the better biological immobilization method to examine the mitigation ability and mechanism of NH₃ production from laying hen manure composting. The results from different immobilized methods showed that NH₃ was reduced by 12.43%, 5.53%, 14.57%, and 22.61% in the cornstalk biochar group, free load bacteria group, mixed load bacteria group, and separate load bacteria group, respectively. Under the simulated composting condition, NH₃ production was 46.52, 38.14, 39.08, and 30.81 g in the treatment of the control, mixed bacteria, cornstalk biochar, and cornstalk biochar separate load immobilized mixed bacteria, respectively. The cornstalk biochar separate load immobilized mixed bacteria treatment significantly reduced NH₃ emission compared with the other treatments (p < 0.05). Compared with the control, adding cornstalk biochar immobilized mixed bacteria significantly decreased the electrical conductivity, water-soluble carbon, total nitrogen loss, and concentration of ammonium nitrogen (p < 0.05), and significantly increased the seed germination rate, total number of microorganisms, and relative abundance of lactic acid bacteria throughout the composting process (p < 0.05). Therefore, the reason for the low NH₃ emission might be due not only to the adsorption of the cornstalk biochar but also because of the role of complex bacteria, which increases the relative abundance of lactic acid bacteria and promotes the acid production of lactic acid bacteria to reduce NH₃ emissions. This result revealed the potential of using biological immobilization technology to reduce NH₃ emissions during laying hen manure composting.

Inoculation of cattle manure with microbial agents increases efficiency and promotes maturity in composting

In this study, fresh cattle manure was mixed with rice straw at a ratio of 10:1 in fresh weight and then composted in a self-built, aerated static composting box, whose dimension was 1 m × 0.8 m × 0.8 m with a volume of approximately 0.6 m³. To deal with the inconvenient and time-consuming problem of multiple stage inoculation, a single, one-time inoculation agent containing diverse microorganisms that are active at both the initial heating and thermophilic phases was developed. A total of 12 from 42 strains isolated from the none-inoculated Experiment 1 composting system were selected as microorganismal agents in Experiment 2 according to their species, prevalence and cultural temperature. 200 mL of each microorganism enrichment broth was mixed to the inoculation group at the beginning of composting. A total of 2400 mL of sterilize distilled water was added to the control group. The parameters of temperature, moisture, pH, C/N ratio, organic matter degradation, and germination index were investigated for both inoculation and control composting groups. Results showed that inoculation did not significantly shorten composting time. However, the pile temperature was increased with the maximum temperatures of 64.6 °C and 60.3 °C for the inoculation and control groups, respectively. The degradation of organic matter was accelerated (P < 0.05), and significantly higher GI value (P < 0.05) indicated that the maturity was promoted by the inoculation microorganism. This suggests that the final composting product would provide value as alternative source of nutrients for plants. Conclusively, we suggested a multiple microorganism inoculation method to increase the efficiency and promote maturity in cattle manure composting.

Lactobacillus plantarum improves the efficiency of sheep manure composting and the quality of the final product

The addition of exogenous microorganisms is one approach with potential that may also overcome the problem in northern China of slow composting in autumn and winter due to low environmental temperatures. This study investigated the use of supplements of Lactobacillus plantarum (L. plantarum), strains P-8 and LP-10, on the efficiency of sheep manure composting and the quality of the final product. The composting process lasted eight weeks and, during this time, changes in multiple physical-chemical parameters and the compost microbiome were monitored. Microbiota-encoded functions, community structure and physical-chemical parameters were distinct between the two groups. 'Composting microbiota maturation index' was proposed to quantitatively compare the impact of maturation on composting microecology. The rapid improvement in composting rate (4 weeks) and quality of the final product suggest that this approach could provide both technological and economic benefits. This work reveals the tremendous potential of L. plantarum as a promoter in composting.

Odor emission and microbial community succession during biogas residue composting covered with a molecular membrane

A membrane-covered composting system was used to investigate the odor emission and microbial community succession during biogas residue composting. Results showed that in comparison with the control (CK) group, the NH₃ and H₂S emissions outside the membrane of the membrane-covered (CT) group decreased by 58.64% and 38.13%, respectively. The nitrogen preservation rate of the CT group was increased by 17.27% in comparison with the CK group. Moreover, the ammonium nitrogen and nitrate nitrogen contents of the CT group were 37.68% and 11.77% higher than those of the CK group, respectively. Microbial analysis showed that the average abundance and co-occurrence rate of ammonification bacteria dominated by Pseudomonas and Bacillus in the CT group were lower than those in the CK group, and the abundance of anaerobic sulfate-reducing bacteria (SRB) dominated by Desulfovibrio in the CT group was higher than that in the CK group.

Influence and characteristics of Bacillus stearothermophilus in ammonia reduction during layer manure composting

Ammonia emissions is an important issue during composting because it can cause secondary pollution and a significant of nitrogen loss. Based on research adding Bacillus stearothermophilus can reduce ammonia emissions during composting because it can use sugar in organic matter fermentation to produce organic acids over 50 °C. This study conducted the batch experiments by adding different concentrations of Bacillus stearothermophilus to reduce the ammonia emissions and find out its characteristic during layer manure composting by using an aerobic composting reactor with sawdust as a bulking agent. The results show that the application of Bacillus stearothermophilus can accelerate the rate of temperature and significantly decrease pH, the warming period was 2 days in the treatment with Bacillus stearothermophilus, while it was 4 days in the treatment without Bacillus stearothermophilus. Ammonia emissions were mainly occurred in warming and high temperature period during composting. The ammonia emissions in the treatment with 8.00 g/kg initial Bacillus stearothermophilus were significantly lower than the other lower Bacillus stearothermophilus treatment and control during composting (p < 0.05), and it can significantly increase ammonium-nitrogen and nitrate-nitrogen concentration, reduce pH (p < 0.05), but the average number of Bacillus stearothermophilus copies in treatment with different initial Bacillus stearothermophilus concentration had no significant difference (p > 0.05). MiSeq System Sequencing results find that the addition of Bacillus stearothermophilus changed the bacterial community structure under warming and high-temperature periods during composting, increased the relative abundance of lactic acid bacillus and nitrification bacteria. Therefore, the reason for the low ammonia emission in 8.00 g/kg initial Bacillus stearothermophilus treatments might be not only due to the Bacillus stearothermophilus itself, but also Bacillus stearothermophilus can change the indigenous microorganism community, including increase the relative content of lactic acid Bacillus and nitrification bacteria, thus reducing the pH and promoting nitrification, and reducing ammonia emissions.

Enzymatic mechanism of organic nitrogen conversion and ammonia formation during vegetable waste composting using two amendments

Elucidating the mechanism of nitrogen conversion during composting is crucial for controlling nutrient loss and improving the quality of compost. To explore the enzymatic mechanism of organic conversion during composting, composting experiments using vegetable waste and chicken manure mixed with wheat straw and corn stalk as two separate treatments: WS and CS, respectively, were conducted in 63 L aerated static pile reactors for 33 d. The changes in the nitrogen fractions and related-enzymes activities were analyzed during different periods. The total nitrogen content increased by 34.3% during WS and decreased by 6.22% during CS after 33d of composting. The ammounium nitrogen content decreased by 79.6% and 51.4% during WS and CS. The nitrate, nitrite, organic, acid-insoluble organic nitrogen contents increased by approximately 52.6-123.9%, 590.9-5875%, 59.1-213.8%, and 764.4-7834.1%, respectively. The amount of total hydrolysable organic nitrogen increased by 18.8% during WS and decreased by 26.7% in CS. Structural equation modeling revealed that the contributions of different types of nitrogen to the formation of NH₄⁺ during WS composting decreased as follows: amine nitrogen (AN) > amino acid nitrogen (AAN) > amino sugar nitrogen (ASN) > hydrolysable unknown nitrogen (HUN), while the corresponding nitrogen contributions during CS decreased as follows: AAN > AN > HUN > ASN. The AN and AAN were most easily converted into NH₄⁺ during WS and CS, respectively, while ASN was synthesized from NH₄⁺ during vegetable waste composting. Using redundancy analysis it was revealed that nitrate reductase (50.1%), nitrite reductase (23.2%) and urease (7.1%) played leading roles in nitrogen transformation. Furthermore, total organic carbon (59.6%) was the main factor that affected enzymes activities.

Effect of Different Proportions of Three Microbial Agents on Ammonia Mitigation during the Composting of Layer Manure

Odor emissions represent one of the important issues of aerobic composting. The addition of microbial agents to compost is an important method for solving this problem, but this process is often unstable when a single microbial agent is added to the compost. Therefore, in this study, five treatments comprising different proportions of Bacillus stearothermophilus, Candida utilis, and Bacillus subtilis were tested to determine the best combination of the three microbial agents for ammonia reduction, as follows: control group (CK), 2:1:1 (A), 1:1:2 (B), 1:2:1 (C), and 1:1:1 (D). Compared with the CK group, the A, B, C, and D groups reduced ammonia emissions by 17.02, 9.68, 53.11, and 46.23%, respectively. The total ammonia emissions were significantly lower in C and D than in CK (p < 0.05). These two treatment groups had significantly increased nitrate nitrogen concentrations and decreased pH values and ammonium nitrogen concentrations (p < 0.05). Throughout the composting process, the total bacterial number was significantly higher in C and D than in CK (p < 0.05). Therefore, it is likely that B. stearothermophilus, C. utilis, and B. subtilis compounded from 1:2:1 (C) to 1:1:1 (D) reduced the ammonia emissions due to (1) a reduction in the pH and (2) the promotion of the growth of ammonia-oxidizing bacteria and the conversion of ammonium nitrogen to nitrate nitrogen. This study provides a theoretical basis and technical support for the odor problem of layer manure compost and promotes the development of composting technology.

Draft Genome Sequence of Caenibacillus caldisaponilyticus B157T, a Thermophilic and Phospholipase-Producing Bacterium Isolated from Acidulocompost

Caenibacillus caldisaponilyticus B157T (= NBRC 111400T = DSM 101100T), in the family Sporolactobacillaceae, was isolated from acidulocompost as a thermophilic and phospholipid-degrading bacterium. Here, we report the 3.36-Mb draft genome sequence, with a G+C content of 51.8%, to provide the genetic information coding for phospholipases.

Dynamic changes of yak (Bos grunniens) gut microbiota during growth revealed by polymerase chain reaction-denaturing gradient gel electrophoresis and metagenomics

OBJECTIVE

To understand the dynamic structure, function, and influence on nutrient metabolism in hosts, it was crucial to assess the genetic potential of gut microbial community in yaks of different ages.

METHODS

The denaturing gradient gel electrophoresis (DGGE) profiles and Illumina-based metagenomic sequencing on colon contents of 15 semi-domestic yaks were investigated. Unweighted pairwise grouping method with mathematical averages (UPGMA) clustering and principal component analysis (PCA) were used to analyze the DGGE fingerprint. The Illumina sequences were assembled, predicted to genes and functionally annotated, and then classified by querying protein sequences of the genes against the Kyoto encyclopedia of genes and genomes (KEGG) database.

RESULTS

Metagenomic sequencing showed that more than 85% of ribosomal RNA (rRNA) gene sequences belonged to the phylum Firmicutes and Bacteroidetes, indicating that the family Ruminococcaceae (46.5%), Rikenellaceae (11.3%), Lachnospiraceae (10.0%), and Bacteroidaceae (6.3%) were dominant gut microbes. Over 50% of non-rRNA gene sequences represented the metabolic pathways of amino acids (14.4%), proteins (12.3%), sugars (11.9%), nucleotides (6.8%), lipids (1.7%), xenobiotics (1.4%), coenzymes, and vitamins (3.6%). Gene functional classification showed that most of enzyme-coding genes were related to cellulose digestion and amino acids metabolic pathways.

CONCLUSION

Yaks' age had a substantial effect on gut microbial composition. Comparative metagenomics of gut microbiota in 0.5-, 1.5-, and 2.5-year-old yaks revealed that the abundance of the class Clostridia, Bacteroidia, and Lentisphaeria, as well as the phylum Firmicutes, Bacteroidetes, Lentisphaerae, Tenericutes, and Cyanobacteria, varied more greatly during yaks' growth, especially in young animals (0.5 and 1.5 years old). Gut microbes, including Bacteroides, Clostridium, and Lentisphaeria, make a contribution to the energy metabolism and synthesis of amino acid, which are essential to the normal growth of yaks.

Degradation of typical antibiotics during human feces aerobic composting under different temperatures

Four typical antibiotics were added to human feces for aerobic composting using batch reactors with sawdust as the bulk matrix. Under three composting temperatures (room temperature, 35 ± 2 °C and 55 ± 2 °C), decreases in the extractable concentrations of antibiotics in the compost were monitored for 20 days. As a result, the removals of extractable tetracycline and chlortetracycline were found to be more temperature-dependent than the removals of sulfadiazine and ciprofloxacin. However, more than 90 % of all of the extractable antibiotics were removed at 55 ± 2 °C. Three specific experiments were further conducted to identify the possible actions for antibiotic removal, including self-degradation in aqueous solution, composting with a moist sterile sawdust matrix without adding feces and composting with human feces and moist sterile sawdust. As a result, it was found that the removal of tetracycline and chlortetracycline was mainly due to chemical degradation in water, whereas the removal of sulfadiazine was mainly attributed to adsorption onto sawdust particles. The microbial activity of compost varied with temperature to a certain extent, but the differences were insignificant among different antibiotics. Although microbial action is important for organic matter decomposition, its contribution to antibiotic degradation was small for the investigated antibiotics, except for ciprofloxacin, which was degraded by up to 20 % due to microbial action.

Caenibacillus caldisaponilyticus gen. nov., sp. nov., a thermophilic, spore-forming and phospholipid-degrading bacterium isolated from acidulocompost

A thermophilic and phospholipid-degrading bacterium, designated strain B157T, was isolated from acidulocompost, a garbage compost processed under acidic conditions at moderately high temperature. The organism was Gram-stain-positive, aerobic, spore-forming and rod-shaped. Growth was observed to occur at 40-65 °C and pH 4.8-8.1 (optimum growth: 50-60 °C, pH 6.2). The strain was catalase- and oxidase-positive. The cell wall contained meso-diaminopimelic acid, alanine, glutamic acid and galactose. The predominant respiratory quinone was menaquinone-7 (MK-7) and the major fatty acids were anteiso-C17 : 0 and iso-C17 : 0. Comparative 16S rRNA gene sequence analysis showed that strain B157T was related most closely to Tuberibacillus calidus 607T (94.8 % identity), and the phylogenetic analysis revealed that it belonged to the family Sporolactobacillaceae. The DNA G+C content was determined as 51.8 mol%. In spite of many similarities with the type strains of members of the family Sporolactobacillaceae, genotypic analyses suggest that strain B157T represents a novel species of a new genus, Caenibacilluscaldisaponilyticus gen. nov., sp. nov. The type strain of Caenibacilluscaldisaponilyticus is B157T (=NBRC 111400T=DSM 101100T).

Inoculation of Pichia kudriavzevii RB1 degrades the organic acids present in raw compost material and accelerates composting

In this study, the yeast strain Pichia kudriavzevii RB1 was used as an inoculum to accelerate organic matter degradation of rabbit food with added organic acids, which was used as a model food waste for composting. The RB1 strain rapidly degraded the organic acids present in the raw compost material, leading to an increase in pH beyond the neutral level, within 2 days. Both mesophilic and thermophilic bacteria proliferated faster in the compost with RB1 inoculation than in that without inoculation. Although the yeast died with the increase in compost temperature, it affected the early stages of composting prior to the thermophilic stage and accelerated the composting process by 2 days by eliminating the initial lag phase seen in the growth of other microorganisms. Moreover, populations of Bacillus thermoamylovorans, Bacillus foraminis, and Bacillus coagulans became dominant during the thermophilic stages of both composting with and without RB1 inoculation.

Characteristics of nitrogen transformation and microbial community in an aerobic composting reactor under two typical temperatures

Batch experiments were conducted for feces composting using an aerobic composting reactor with sawdust as bulky matrix. In the 14-day composting processes at 35±2 and 55±2°C, compost samples were collected daily and chemical analyses and PCR-DGGE were carried out for investigating the influence of composting temperature on organic decomposition, nitrogen transformation, and microbial communities. At 55±2°C, in addition to a slightly higher COD removal, nitrogen loss was greatly restrained. As organic nitrogen took about 85% of the total nitrogen originated from human feces, the suppression of ammonification process under thermophilic environment might be the main reason for less nitrogen loss at 55±2°C. By PCR-DGGE analysis, the microbial community was found to undergo successions differently at 35±2 and 55±2°C. Certain sequences identified from the compost at 55±2°C represented the microbial species which could perform nitrogen-fixation or sustain a lower pH in the compost so that gaseous ammonia emission was suppressed.

Quantitative analyses of the behavior of exogenously added bacteria during an acidulocomposting process

The behavior of adventitious bacteria during an acidulocomposting process was quantitatively analyzed in garbage-free trials. The numbers of the added Bacillus subtilis and Pseudomonas putida cells diminished in a first-order manner with t(1/2) values of 0.45d and 0.79d, respectively, consistent with the observed stability of the acidulocomposting function.

Dynamics of bacterial communities during solid-state fermentation using agro-industrial wastes to produce poly-γ-glutamic acid, revealed by real-time PCR and denaturing gradient gel electrophoresis (DGGE)

The dynamics of bacterial communities play an important role in solid-state fermentation (SSF). Poly-γ-glutamic acid (γ-PGA) was produced by Bacillus amyloliquefaciens C1 in SSF using dairy manure compost and monosodium glutamate production residuals as basic substrates. The production of γ-PGA reached a maximum of 0.6% after 20 days fermentation. Real-time polymerase chain reaction showed the amount of total bacteria reached 3.95 × 10(9) 16S rDNA copies/g sample after 30 days, which was in good accordance with the 4.80 × 10(9) CFU/g obtained by plate counting. Denaturing gradient gel electrophoresis profile showed a reduction of microbial diversity during fermentation, while the inoculum, B. amyloliquefaciens C1, was detected as the dominant organism through the whole process. In the mesophilic phase of SSF, Proteobacteria was the dominant microbial, which was replaced by Firmicutes and Actinobacteria in the thermophilic phase. The molecular analysis of the bacterial diversity has significant potential for instructing the maturing process of SSF to produce γ-PGA at a large-scale level, which could be a benefit in the production of high quality and stable SSF products.