Onion Waste Research Articles

Development of multilayer composite film based on protein‐polysaccharides with the addition of onion waste extracts and their impact on the shallot quality

AbstractAt present, multilayer composite film is attractive in the production of biodegradable films due to its essential film properties. The current study mainly focused on overcoming the problems of poor water barrier and mechanical strength observed in monolayer films (SA‐CMC and G/SA‐CMC) made from gluten (G), sodium alginate (SA), and carboxymethylcellulose (CMC). The film was developed with the addition of onion waste extracts (OWEs), primarily from peel and stalk, to enhance functional properties. The multilayer composite film consists of three layers: an outer layer made of G, an inner layer made of SA, CMC, and a middle layer made of G/SA‐CMC. The developed composite film exhibited improved physical properties (thickness: 0.348–0.629 mm and moisture: 20.889%–21.403%), mechanical properties (tensile strength: 21.943–20.640 MPa), and barrier properties (WVP: 0.212–0.516 g/m.s.Pa × 10−14) compared to monolayer films (SA‐CMC and G/SA‐CMC). The addition of OWEs enhanced the multilayer film's phenolic (20.076 and 36.175 mgGAE/g) and antioxidant activity (73.850% and 42.667%). The study found that the multilayer control film had minimal changes in weight loss (9.75% ± 0.18%) and firmness (6.68 ± 0.64 N) compared to OWEs‐added films (9.93% ± 0.49–10.02% ± 0.14% and 6.61 ± 0.37 to 6.64 ± 0.18 N). However, fresh‐peeled shallot onion packed with control film exhibited higher bacterial counts (6.70 ± 0.42 CFU/g) and yeast and mold counts (5.08 ± 0.20 CFU/g) than those packed with the OWEs‐added film (6.49 ± 0.28–6.56 ± 0.27 CFU/g and 4.75 ± 0.18–4.89 ± 0.21 CFU/g), indicating that OWEs protect the onions from microbial degradation. Overall, the multilayer control film (without OWEs) showed better results for storing the fresh‐peeled shallot onion at 4°C for 21 days.Highlights Onion waste extracts have potent high antioxidant and antimicrobial properties Multilayer film's physical, mechanical, barrier, and functional properties improved Addition of onion waste extracts increased the film's antimicrobial activity Control film showed a better effect for storing fresh‐peeled shallot onion Developed film can store fresh‐peeled shallot onion for 21 days at 4°C.

Studies on unlocking the potential of onion waste extracts in edible coating for shelf-life extension of strawberry

Studies on unlocking the potential of onion waste extracts in edible coating for shelf-life extension of strawberry

Insights into bioactive constituents of onion (Allium cepa L.) waste: a comparative metabolomics study enhanced by chemometric tools

BackgroundOnion waste was reported to be a valuable source of bioactive constituents with potential health-promoting benefits. This sparked a surge of interest among scientists for its valorization. This study aims to investigate the chemical profiles of peel and root extracts of four onion cultivars (red, copper-yellow, golden yellow and white onions) and evaluate their erectogenic and anti-inflammatory potentials.MethodsUPLC-QqQ-MS/MS analysis and chemometric tools were utilized to determine the chemical profiles of onion peel and root extracts. The erectogenic potential of the extracts was evaluated using the PDE-5 inhibitory assay, while their anti-inflammatory activity was determined by identifying their downregulating effect on the gene expression of IL-6, IL-1β, IFN-γ, and TNF-α in LPS-stimulated WBCs.ResultsA total of 103 metabolites of diverse chemical classes were identified, with the most abundant being flavonoids. The organ’s influence on the chemical profiles of the samples outweighed the influence of the cultivar, as evidenced by the close clustering of samples from the same organ compared to the distinct separation of root and peel samples from the same cultivar. Furthermore, the tested extracts demonstrated promising PDE-5 and anti-inflammatory potentials and effectively suppressed the upregulation of pro-inflammatory markers in LPS-stimulated WBCs. The anti-inflammatory activities exerted by peel samples surpassed those of root samples, highlighting the importance of selecting the appropriate organ to maximize activity. The main metabolites correlated with PDE-5 inhibition were cyanidin 3-O-(malonyl-acetyl)-glucoside and quercetin dimer hexoside, while those correlated with IL-1β inhibition were γ-glutamyl-methionine sulfoxide, γ-glutamyl glutamine, sativanone, and stearic acid. Taxifolin, 3’-hydroxymelanettin, and oleic acid were highly correlated with IL-6 downregulation, while quercetin 4’-O-glucoside, isorhamnetin 4’-O-glucoside, and p-coumaroyl glycolic acid showed the highest correlation to IFN-γ and TNF-α inhibition.ConclusionThis study provides a fresh perspective on onion waste as a valuable source of bioactive constituents that could serve as the cornerstone for developing new, effective anti-PDE-5 and anti-inflammatory drug candidates.

Onion Peel Waste Has the Potential to Be Converted into a Useful Agricultural Product to Improve Vegetable Crop Growth

The onion processing industry produces hundreds of thousands of tons of onion waste annually. Normally, onion peel waste is dumped in landfills, which creates additional sources of greenhouse gases. Research has validated that onion peel is a concentrated source of bioactive compounds; therefore, it can be turned into useful agricultural products such as soil amendments and possibly biostimulants. This study conducted three experiments to investigate the plant growth-promoting potential of an onion juice concentrate (OJC). The first experiment explored whether the application of OJC could increase plant growth of Bermuda grass, lettuce, and bok choy. The second experiment evaluated the effects of foliar and subsurface drench applications of OJC on bok choy and lettuce growth. The third experiment investigated the interaction between OJC application methods and fertilizer type on bok choy and radish growth. The results indicated that foliar applications of OJC of 1% to 2% concentrations increased the yield of bok choy and its overall growth. Subirrigation with OJC, however, enhanced the root growth of bok choy, lettuce, and radish. Notably, the combined approach of foliar and subirrigation applications further promoted the growth of both bok choy and radish. Comparing across experiments, longer OJC application periods emerged as a promising strategy for amplifying its growth-promoting benefits. Overall, our findings suggest that OJC holds promise for promoting sustainable agriculture. This potential comes from its ability to enhance both the growth and yield of vegetable crops like bok choy, lettuce, and radish while simultaneously reducing waste.

Combustion Analysis of Solid Biomass Derived from Turmeric and Onion, using Nanoclay as a Binding Material, for a Sustainable Environment

The usage of fossil resources has promoted wealth accumulation, exacerbated the negative effects of climate change from GHG emissions, and jeopardized human safety. This research focuses on the utilization of locally generated waste from Turmeric Wastes (TW) and Onion Wastes (TW) for the production of biomass briquettes, employing 10% nanoclay powder as a binder. The biomass waste mixtures were prepared at different ratios, namely 0:100 (C1), 30:70 (C2), 60:40 (C3), 90:10 (C4) and 100:0 (C5), with a constant binder concentration. Densification can be used to turn these residues into elevated, fuel-efficient biomass feedstock. Analysis was carried out for wet content, content of volatile matter and content of fixed carbon. SEM evaluations with EDAX studies were done to identify the major elements available in the produced Turmeric waste - Onion waste briquettes. TGA and DSC investigation implicated the recognition of the burning stage of exothermic and endothermic peaks of the produced briquettes. The briquettes generated exhibit a range of total calorific values, spanning from 11.66 to 15.64 MJ/kg. Notably, these briquettes demonstrate an ignition time within the range of 3.3 to 4.0 seconds and a sustained burning duration lasting between 20 to 28 minutes. Consequently, the utilization of TW-OW in combination with 20% nanoclay binder presents a viable alternative energy source. This is attributable to the briquettes' commendable characteristics, including low moisture and ash content, coupled with a notably high calorific value.

Natural cellulosic biofunctional textiles from onion (Allium cepa L.) skin extracts: A sustainable strategy for skin protection

Cellulosic fabrics made of cotton, linen, bamboo, hemp, and nettle, were selected for the eco-sustainable production of colored biofunctional textiles, using natural dyes from onion skin of the Dorata di Parma (Allium cepa L.) variety. Dyeing experiments were performed in net water with and without pre-treatment with alum, tin chloride, and tannic acid as mordants. The color and the UV-protection factor (UPF) were evaluated through UV–visible spectroscopy. The treatment with onion skin extract induced a relevant increase of UPF in all investigated fabrics, promoting the protection category from insufficient (UPF<15) to good for linen (UPF = 21–26), up to very good and excellent for cotton (UPF = 35–66) and bamboo (UPF = 48–56), respectively. To mimic the direct contact with the skin, textile samples were immersed in artificial sweat where dyed cotton, hemp, and nettle were found to promote higher phenolic release (0.28–0.50 mg gallic acid equivalents/g textile) than linen and bamboo (0.12–0.22 mg gallic acid equivalents/g textile). The obtained “biofunctional sweat” did not impact on the survival of primary human dermal fibroblasts (HDF) and skin keratinocytes (NCTC2455), while protected these cells against heat shock and reduced reactive oxygen species levels upon exposure to pro-oxidant and inflammatory agents as H2O2 and lipopolysaccharide, respectively. Increased activity levels of the H2O2-scavenging enzyme Catalase (CAT) were also observed, thus demonstrating enhanced stress response and homeostatic capability of these cells. This study provides evidence that extracts from onion waste can be used to functionalize cellulosic fabrics conferring properties as natural shield against UV radiation, and antioxidant and anti-inflammatory materials thus holding potential in skin protection and prevention of dermatological diseases.

Probing Anticancer Molecules from Onion Peels Waste; First Synthesis and Biological Studies of a Rare Quercetin Derivative-Pachypodol

Background: The constant increase in global onion production escalates the generation of onion peel waste. For instance, globally, &gt;50 lakh tons of onion waste are generated annually. Methods: Its objectionable odor precludes its use in agriculture or disposal as landfilling presents environmental issues. Previous studies show that two major flavonoids, quercetin and its glycosides (spiraeoside), have been identified in abundance in onion waste. By utilizing the spiraeoside (quercetin-4ʹ-glucoside), a rapid synthesis of pachypodol (quercetin-3,3′,7-trimethyl ether, and a rare flavonol), an essential Ayurvedic product, has been developed and achieved. Pachypodol and analogs were studied for their ability to inhibit matrix metalloproteinase-2 and -9 (MMP-2 &amp; 9) activity. Amongst the compounds tested, pachypodol significantly inhibited MMP-2 activity. Results: In-silico docking studies suggest that, unlike most known MMP inhibitors, pachypodol interacts selectively with MMP-2 through the residues Ile222, Tyr223, and Thr227 in a zincindependent manner. Conclusion: The experimental studies also prove that pachypodol inhibits the MMP-2 enzyme in a zinc-independent way.

Microwave-assisted extraction of pectin from onion and garlic waste under organic, inorganic and dual acid mixtures

This study aims to investigate pectin extraction from garlic (GW) and onion waste (OW) by microwave-assisted (MAE) and sequential microwave assisted-hot acid extraction (MAHE) methods. All extractions were performed under three different media including organic acids [citric (CA) and acetic (AA)], inorganic acids [sulfuric (H2SO4) and hydrochloric (HCl)] and their mixtures. GW provided more pectin yields compared with OW. While the highest pectin yields from GW and OW by MAE in H2SO4 were respectively 24.62 ± 0.65 and 24.93 ± 0.59%, these yields under MAHE were 27.99 ± 0.36 and 28.43 ± 0.42%, respectively. Higher pectin yields and galacturonic acid (Gal-A) contents were mostly achieved in inorganic acids. However, degree of esterification (DE), methoxyl content (MeO) and equivalent weight (EW) values were higher for the pectins extracted under organic acids. Extraction of pectin from GW and OW was also accomplished in dual acidic media by MAE. Addition of inorganic acids to the organic acid solutions resulted in increasing pectin yields. The highest pectin yields from GW and OW under dual acid solutions were respectively 23.36 ± 0.66 and 21.88 ± 0.52%, and achieved in 1/3 HCl-H2SO4 and 1/3 CA-H2SO4 mixtures by MAE. While increasing inorganic acid contents in dual acid solutions resulted in enhanced Gal-A contents, increasing organic acid volume also generated higher DE and MeO values of the pectins. Obtained successful outcomes indicate that MAHE method could be used as an efficient extraction technique for the higher pectin yields, and utilization of organic-inorganic dual acid mixtures during MAE provides enhanced yields and controlled physicochemical properties of pectin.Graphical abstract

Cobalt Oxide-Decorated on Carbon Derived from Onion Skin Biomass for Li-Ion Storage Application

Onion waste, particularly onion skin, is a widely generated waste material, and harnessing its potential for energy storage aligns with sustainable development goals. Despite the high specific surface area exhibited by biocarbon derived from onion skin, its Li-ion storage performance is not desirable. In this study, biocarbon derived from purple onion skin serves as the substrate for accommodating cobalt oxide (Co3O4) through a hydrothermal method, employing Co(NO3)2·6H2O at various concentrations, and with and without prior activation using KOH treatment. The resulting samples undergo comprehensive analyses, including phase, morphological, surface, and electrochemical characterizations. The Co3O4 decoration on activated carbon derived from onion skin, synthesized using Co(NO3)2·6H2O at a concentration of 1 M, reveals a porous structure with a surface area of 702 m2/g, featuring predominant pore sizes of less than 5 nm. Significantly, the Li-ion storage performance of this sample surpasses that of alternative samples, demonstrating a remarkable reversible capacity of 451 mAh/g even after 500 cycles at an elevated current density of 2000 mAh/g. The charge transfer resistance of the sample (110.3 Ω) is found to be substantially lower than that of the sample prepared using carbonized onion skin biomass without activation. This research introduces an innovative approach leveraging onion skin waste as a template for Co3O4 decoration, thereby fabricating high-performance anodes for lithium-ion batteries.

Green synthesis of DL-homocysteine decorated magnetic nanoparticles for selective and efficient mercury remediation from simulated wastewater: Kinetics, isotherm, and mechanism studies

The present study focuses on the facile green synthesis of magnetic nanoparticles (MNPs) using onion waste of Allium Cepa L. (MNP@OW) for effective removal of noxious mercury from simulated wastewater. Photogenically synthesized MNPs were functionalized with DL-homocysteine (HC@SiO2@MNP@OW) for selective mercury adsorption. Various characterization techniques were employed to confirm their physical properties. Vibrating sample magnetometer (VSM) studies indicated MNP@OW’s superparamagnetic nature with a saturation magnetization (Ms) of 48.35 emu/g, while HC@SiO2@MNP@OW had a reduced Ms of 4.52 emu/g due to a coating of non-magnetic silica and DL-homocysteine. Both adsorbents showed optimal adsorption at 80°C and pH 8. However, it is explicitly mentioned that HC@SiO2@MNP@OW demonstrated efficient mercury removal at a lower dosage and shorter contact time compared to MNP@OW. Fast separation times of 6 and 26 seconds for MNP@OW and HC@SiO2@MNP@OW, respectively, confirm their ease of separation from simulated wastewater. The Freundlich isotherm model fit the data well and kinetic analysis supported a pseudo-second-order model, revealing a chemisorption mechanism. Moreover, HC@SiO2@MNP@OW demonstrated high selectivity, even in the presence of co-existing ions. Green synthesized MNP@OW and HC@SiO2@MNP@OW exhibited promising potential as low-cost sorbents for efficient mercury removal from simulated wastewater, making them feasible for wastewater treatment in low-economic countries.

Sustainable Recovery of Antioxidant Compounds from Rossa Di Tropea Onion Waste and Application as Ingredient for White Bread Production

From a sustainability and circular economy point of view, this study evaluated the possibility of recovering antioxidant compounds from Rossa di Tropea onion waste for application in the food industry as natural ingredients. In particular, the aim was to investigate the effect of adding natural antioxidants recovered from ‘Rossa di Tropea’ onion waste to maintain/improve the functional and qualitative characteristics of white bread. Total phenolic content, antioxidant activity, and sensorial aspects were studied on the different enriched samples during the storage period. The ‘Rossa di Tropea’ onion skins proved to be a good source of natural polyphenols, and their use in white bread production has resulted in a significant increase in bioactive compound content and antioxidant activity (ABTS and DPPH assays). Moreover, the enriched bread showed acceptable quality attributes in terms of odor, colour, and taste, despite the increase in firmness during the storage time compared to the control sample. The obtained results suggest the possibility of applying the antioxidants recovered by ‘Rossa di Tropea’ onion waste as ingredients in the formulation of bakery products to obtain new food with functional characteristics.

Handmade Paper Formation from Onion Peels

Every year above 15 million trees are cut down for various purposes. In which around 8 million trees are only cut down for paper production. This number is increasing every year which is causing climate calamities, disappearance of wildlife, emission of greenhouse gases, soil erosion, etc. We can’t stop the use of paper, but we can find an alternative for making of it. Every year tons of onion waste are produced worldwide in which outer onion skin contributes up to 70% of this waste. This waste can cause environmental problems when not properly treated. In this paper, an attempt has made for production of paper using onion peels. For the pulping of onion skin soda process has been used. Paper produced was light and white and can be used for decorative purposes.

Comparisons of pulsed ultrasound-assisted and hot-acid extraction methods for pectin extraction under dual acid mixtures from onion (Allium cepa L.) waste.

The aim of this study is to compare the physicochemical properties and yields of pectins extracted from onion waste under hot acid (HAE) and pulsed ultrasound-assisted extraction (PUAE) methods using different organic-inorganic acids, their mixtures, and pure water. The extraction temperature for experiments carried out under HAE was kept at 90°C for 90 min, whereas PUAE experiments were accomplished at RT in 15 min. In general, HAE gave better pectin yields compared with PUAE due to the significance of the increasing extraction temperature for the release of pectin from the plant matrix. While the maximum pectin yield from onion waste was 16.22% for HAE, the highest yield for PUAE was 9.83%. PUAE provides less time- and energy-consuming extraction of pectin within 15 min and thus seems to be more economic compared with the HAE. According to the physicochemical properties (equivalent weight (EW), degree of esterification (DE), methoxyl (MeO), and galacturonic acid (Gal-A) contents) of obtained pectins, extracted pectins were mostly high methoxy pectin. While the DE and MeO values of pectins extracted in organic acid conditions under HAE were higher, these values were found to be higher for pectins extracted in inorganic acids under PUAE. For acid mixtures, the DE and MeO values of pectins under HAE were mostly found to be lower than those under PUAE. Sequential PUAE and HAE methods for the extraction of pectin from onion waste were also found to be useful in terms of obtaining higher yields and better physicochemical properties. The highest pectin yield was 20.32% for the sequential PUAE and HAE methods. FT-IR analyses of the extracted pectins by both HAE and PUAE methods showed similar vibration bands compared with those of commercial citrus pectin.

Valorization and structural characterization of onion peel powder for the development of functional bread

ABSTRACT Valorization of food waste has gained much popularity in current era due to the occurrence of various bioactive components in it. By-products obtained from the processing of onion are rich and dense source of bioactive components that can provide health-promoting effects when incorporated in various functional foods. Current study was conducted for the development of onion peel powder (OPP)-enriched bread. Moreover, the effect of onion waste supplementation on bread was further characterized structurally and functionally by scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy. Overall, the mean results showed the addition of OPP significantly (p <0.05) modified the overall characteristics of functional bread as well as improved its antioxidant potential. The rheological properties determined through mixographic and farinographic analysis showed that the OPP added bread results in more stable dough having 64.67%, tolerance index 134.11% softness and while 6.32 min mixing time and 54.24 ± 0.08 BU peak height. The total phenolic contents (TPC) and flavonoid content (FC) of functional breads also increased while a visible increase in DPPH activity of functional breads was observed. However, SEM revealed the OPP-enriched bread had less fine protein structure because of the presence of higher fiber content as compared control sample while the FTIR analysis revealed the presence of various functional groups in OPP bread.

Effects of Sub-acute Administration of Onion Waste Quercetin on the Hippocampus of Mice: A Histological Approach

Quercetin is a flavonoid with a great capability of crossing the blood-brain barrier. It is reported to exert numerous beneficial effects on both animal and human health. The study evaluates the effects of onion waste quercetin (OWQ) on the histology of the hippocampus and dentate gyrus of mice. Twenty mice were assigned into four groups (n=5). The groups were given distilled water, and OWQ at 95mg/kg, 190mg/kg, and 380mg/kg respectively for 28 days. The brain of each mouse was harvested afterward, weighed, and processed for light microscopy. The normal and degenerating cells in the dentate gyrus and hippocampus Cornu Ammonis (CA1 &amp; CA3) were counted. The micrographs of the dentate gyrus showed normal molecular, granular, and polymorphic layers in the control mice, as well as the mice, treated with OWQ with few degenerating cells in the granular layer of OWQ-treated (190mg/kg) mice. The CA3 area of the hippocampus showed normal molecular and polymorphic layers in OWQ-treated mice. However, the granular layer of the mice that received OWQ at 190mg/kg showed numerous degenerating cells. OWQ especially at 95mg/kg was found to significantly increase the number of normal cells in the dentate gyrus and hippocampus (CA1 &amp; CA3) of the brain compared to the control at P&lt; .05. It also significantly decreased degenerating cells compared to the control (P&lt; .05). In conclusion, onion waste quercetin, especially at 95mg/kg was found to maintain the pool of normal cells within the dentate gyrus and hippocampus of mice brain.

Efektivitas Pupuk Organik Cair Bawang Merah dan Limbah Bawang Merah Terhadap Perubahan Sifat Kimia Tanah dan Pertumbuhan Bawang Merah

Soil has an important role "in agriculture for the growth and production" of plants. The combination of organic and inorganic fertilizers can increase crop productivity and improve soil quality on land so that it can be used sustainably. One of the potential plants that can be used as a basic ingredient of organic fertilizer is red onion. This study aims to determine the effect of red onion liquid organic fertilizer on changes in soil chemical properties and plant growth. This research was conducted using a factorial randomized block design (RBD) with 2 factors. The first factor is the dose of organic fertilizer and the second factor is the dose of inorganic fertilizer. Parameters observed were pH, C-Organic, N, P, K, tuber weight, plant fresh weight, number of leaves and plant height. The results showed that red onion organic fertilizer can lower soil pH and increase soil C-Organic, N, P and K. The combination of the D1KB2 treatment (50% basic fertilizer + 15,000 ppm red onion waste) gave the best results in increasing soil organic C, Phosphate and Potassium. Conclusion. The interaction of inorganic fertilizers and red onion liquid organic fertilizer had a significant effect on tuber weight and plant wet weight, and had no significant effect on plant height and number of leaves.

Chemical activation and magnetization of onion waste derived carbon for arsenic removal

Arsenic is a known human carcinogen and its contamination of drinking water has been a global challenge. In this study, magnetic activated carbon (MAC) as an efficient adsorbent material was synthesized by hydrothermal method. Three adsorbent materials MCH, MCH3 and MCNa were synthesized using different chemical activators like HNO3, H3PO4 and NaOH respectively. Structural and morphological features of the adsorbents before and after magnetization were determined by XRD, FTIR, FESEM, EDX and TGA. BJH nitrogen adsorption–desorption isotherm was used to find the surface area and pore size of adsorbents while the surface charge was determined by measuring zeta potential. FESEM images clearly showed the incorporation of magnetite nanoparticles into a porous network. The XRD further confirmed the formation of magnetite nanoparticles within the network of porous carbon with average crystallite sizes of 6.3, 5.8, 5.5 nm for MCH, MCH3 and MCNa respectively. To examine the adsorption behaviour of As(III) onto the MAC, batch adsorption experiments were conducted with the effect of different parameters like initial concentration, temperature, time, amount of adsorbent and pH. The results showed that MCNa is a potential adsorbent for As(III) with removal efficiency of 99%. Overall adsorption process follows pseudo 2nd order kinetics while the Langmuir model was found well applicable to the experimental data. Thermodynamics of adsorption and desorption studies suggest that chemisorption is a predominant adsorption mechanism. Cost-effectiveness, novelty and magnetic recovery are the key features making onion-based MAC a potential adsorbent for the removal of As(III) from contaminated water.

Optimizing extraction of antioxidative biostimulant from waste onion peels for microalgae cultivation via response surface model

In this study, a novel and cost-effective method for using onion peel as a biostimulant is presented to overcome the challenge of low microalgae biomass productivity. The study successfully optimized and modelled the extraction parameters, including solid-to-solvent (SS) ratio, temperature, and time, using the response surface methodology (RSM) tool. The results indicated a strong correlation between the extraction parameters and microalgae biomass concentration (BC) and lipid content (LC), with R2 values of 0.9440 and 0.9638, respectively. The optimum biostimulant extraction conditions were SS ratio of 0.006 g/mL, temperature of 90 °C at 1.00 h, attaining BC and LC of 1.76 g/L and 19.42 %, respectively, without any negative impact on LC. Findings on bioactivities of biostimulant recovered at optimal extraction conditions supported its biostimulation capacity on microalgae, with reasonable total phenolic content (TPC) of 9.1094 ± 0.748 mg GAE/g dry weight, total flavonoid content (TFC) of 3.1307 ± 0.210 mg RE/g dry weight, and antioxidant activity (AA) of 78.65 ± 3.421 % and 73.68 ± 9.608 % for DPPH and ABTS inhibition, respectively. The results of this study suggest that biostimulant derived from onion waste has great potential for promoting rapid proliferation of microalgae even with extremely low inoculum cells. These findings present a promising roadmap for high-density microalgae farming, and the developed RSM model can be utilized for process optimization while improving the efficiency, quality, and cost-effectiveness of microalgae industry.

Physicochemical and Biological Evaluations of Packaged Chips and Meat balls Produced from Broiler Chicken Fed Diets Supplemented with Onion Wastes for Sustainability

Physicochemical and Biological Evaluations of Packaged Chips and Meat balls Produced from Broiler Chicken Fed Diets Supplemented with Onion Wastes for Sustainability

Understanding Food Loss and Waste in the Onion Growing Industry in Aotearoa New Zealand

Sustainable growth and improving the profitability of onion growers and exporters is Onions New Zealand’s vision. Alongside marketable product, minimizing and converting onion industry loss and waste products into a useable form is one piece of work requiring further exploration. My project involved a series of interviews with growers and processors to discuss the amount of waste generated in the industry, and to try and quantify the opportunity from turning this into product of value. Join me to hear about the some of the work being done with growers and processors to understand the size of the opportunity and to help Onions New Zealand’s achieve this vision for this sector. Supervised by: Professor Miranda Mirosa and Trixie Croad, Food Waste Innovation Otago Scholarship funded by: Onions NZ