Utilization of Ginger and Its Waste

Ginger has become the focus of research because of its oleoresin and essential oil content. First, the drying process can maintain the quality of post-harvest products and increase the shelf life of dry products. Applying heat by air, microwave, vacuum, and freeze-drying can remove up to 5% (w.b.) of the moisture content of the material. High temperatures provide a greater driving force and result in the best possible product damage. The involvement of an adsorption dryer can be an opportunity to carry out drying at low temperatures by involving a dehumidified air agent. Apart from drying, the extraction process is an essential component of the ginger isolation technique. In addition to temperature, the physical properties involved in this process are density and pressure (having relatively great difficulty in achieving the desired properties). Significant components with GC-MS and GLC tests gave different peak area results from the drying and extraction processes. However, β-phellandrene and camphene represent the presence of ginger essential oil in both methods. Then, the pulp and skin can also be reprocessed through extraction to produce ginger oil and ginger pulp. The sustainability of ginger residue through pyrolysis can produce ginger charcoal products. Meanwhile, the ginger pulp contains sugar, acid, and micro-fibrillation of cellulose (MFC) through hydrolysis. The results of research related to ginger provide opportunities for SMEs to produce post-harvest products in red ginger powder. The extraction process with polar solvents and the role of appropriate technology have encouraged independent economic activities. In addition, dregs from raw materials and by-products can be exploited for opportunities to reduce the waste generated.


Introduction
Ginger (Zingiber officinale) is a tropical plant thrives in hot, humid environments.China, Nepal, the United States, India, Bangladesh, Taiwan, Jamaica, Nigeria, and Indonesia grow the plant.India tended to produce the most ginger.In Indonesia, Zingiber officinale is one of the export commodities, with a development area of 6,053 hectares in 2010 and a rhizome need of 12,106 tons per year [1].Food, flavour enhancers, fragrances, and pharmaceuticals have benefited from ginger rhizome [2].Sure, researchers have treated fresh ginger through a drying and extraction process.The purpose is to extract the most vital components, oleoresin and essential oils, from the plant.Ginger root is also used to relieve and treat various ailments, including headaches, colds, nausea, and emesis [3].Ginger also have many bioactive components, such as phenolic and terpene compounds.The phenolic chemicals gingerols, shogaols, and paradols component for the diverse bioactivities of ginger.Camphene, β-myrcene, βphellandrene, borneol, and α-farnesene are the primary components of ginger flavour [4].Nigeria, Australia, Jamaica, and Haiti, have utilized it for culinary and therapeutic benefits [5].Because of the diverse geographical areas, the chemical composition of fresh ginger varies [6].
Researchers [7] studied the volatile components of ginger through a variety of drying processes (shown in Fig 1).The goal of the drying process is to reduce the amount of water in the product and extend its shelf life.The addition of hot air reduces the concentration and activity of antioxidants while also providing some novelty to other components.The drying process resulted in the development of some volatile features absent in fresh ginger pulp and the removal of others [7].The ginger sample that gave preliminary treatment had higher rehydration capability after the drying process than not another one got it.This way guarantees that the pretreatment produces a more compact structure after drying.Consequently, the effectiveness of pretreatment could improve the model's performance in estimating the moisture content of ginger in the drying process for tray drying [8].
The explanation of the methods and research results from the use of ginger provides insight into the goals of ginger farmers, one of which is the desire for high selling prices and the long shelf life of ginger after harvesting activities take place.However, this simple effort gave the opposite.The demand for a post-harvest follow-up process is an opportunity to overcome the wishes of the farmers and is also a step to integrate research results into service products at MSME (Micro, Small and Medium Enterprise) locations.Wet ginger products are transformed into dry products and are ready to be consumed by humans because of the benefits it has.The treatment of reducing water content and the involvement of the extraction process with polar solvents are alternatives to producing ginger products.They can be transported to various regions in Indonesia.
The relationship of this paper with sustainable development goals provides opportunities for greater utilization of ginger raw materials, both as fresh feed and waste.Processes such as extraction and drying will provide improved post-harvest steps and economics by making it a product that has a longer shelf life.Other processes, namely pyrolysis and hydrolysis, are also alternatives to increasing the function of ginger for the health of the human body in the form of ginger oil, extract (yield), and even residue.The hope is that the use of ginger as a sustainable product can be applied not only by industry but also by MSMEs.

Research method
Many researchers have carried out various processing methods for ginger, presented in Figure 1.The application of these steps is handling fresh ginger raw materials into long shelf-life products to maintain their chemical content.The waste (from raw materials ginger and by-products) can be continued to produce derivative products such as ginger oil and its residues, ginger char, bio-oil, sugar and acid, starch and cellulose materials (Figure 2).The presentation of Figure 2 is adopted from [9].

Result and discussion
The research results from many researchers below are the output of providing processing for ginger raw materials in the form of drying, extraction, isolation techniques for an essential component of ginger, to the expansion of drying-extraction technology.The pulp of ginger has also become the focus of other researchers to extract several extracts and ingredients of the sale value.
Table 1 shows the results of ginger identification before and after the procedure treatment.Water drying (T=50-60 o C), followed by freeze-drying, produces an increase, reduction, and even the components in fresh ginger vanish as the water content decreases.The predominant element of ginger flavour, camphene, β-myrcene, β-phellandrene, and borneol, becomes a minor after drying [7].If dried products are matter consumed, the need for additional types of ginger (known as red ginger or ginger "emprit" in Indonesia) becomes a step to increase the spicy taste or taste for MSME.Adsorption dryer with zeolite is an opportunity to carry out drying at low temperatures.The dehumidified water agent takes the water content of the material.Zeolite causes the incoming air's humidity to decrease, and the driving force for drying increases.Thus, the drying process takes place at low temperatures and keeps the quality of seaweed products [12], [13].maintains its natural characteristics.The optimum condition achieved was 0.8 g ml -1 .Supposedly, the higher the fluid density gives, the increase in triglycerides.However, the difficulty of adjusting the fluid density resulted in the presence of glyceride contamination which reduced the quality of the extract [6].The timeline of ginger harvesting has an important role.The presence of geranyl acetate contributes to paying attention to the time from planting to harvesting [14].The low value of these components is the focus of other researchers.
Note: *dominated component from 90 alkenes in total which identified by GC-MS, [14], [16] [15] by GLC, extraction after γ-irradiated from ginger paste + peroxide-free diethyl ether, with yield volatile oil = 0.14% of 50 g sample The ginger and turmeric blend's supercritical (SC) fluid process focuses on starch recovery.The two materials have approximately 45 and 40%, respectively [15].The ginger treatment involves CO2 and isopropyl alcohol (1.5% v/v) at a pressure of 250 bar and 35 o C, which adopts the working steps of [16].Utilized extraction solvent could affect ginger's antioxidant activity.An ethanolic ginger extract demonstrated a high Trolox-equivalent antioxidant capacity and ferric-reducing ability, but an aqueous ginger extract displayed potent free radical scavenging and chelating activity [18].Then, turmeric takes advantage of the same thing through researchers [19], a mixture of CO2 with co-solvent (10% v/v) ethanol or isopropyl alcohol at a pressure of 300 bar and 30 o C.
Another extraction technique to obtain ginger components (especially gingerols) is liquid carbon dioxide.Researcher [10] used crushed dry ice in the cylinder of glass Soxhlet extractor (inside) to evaporate carbon dioxide.The raw material used is not fresh ginger but freeze-dried ginger.On the equipment's outer jacket, propylene glycol was utilized as a medium heater and stabilized extractor at 600-700 psi.This method contrast to researchers [6] who feed CO2 gas to the process stream.The study results [10] showed that the indication of gingerol components using HPLC, maximum UV absorption at 282 nm (range 200 -400 nm as a variable condition) and gave 74.95% gingerol fraction.
From the research results presented, the treatment of ginger focuses on the acquisition of volatile oils from ginger.Various methods are different from the goals of ginger farmers who want to sell products (solid form) and become daily health drinking products.The extraction technique with polar solvents (no chemicals and affordable prices) and followed by the evaporation process is an approach solution for MSMEs in pioneering creative economic empowerment [20], [21].
Not only fresh ginger but pulp processing is also sustainable.An extraction process is an option for the ginger waste container industry to produce ginger dregs.The pulp is treated with a hydrolysis process and produces products in biopolymers and micro-fibrillation of cellulose (MFC).Second, the following is the pyrolysis process with hydro-chars and bio-oils [9]. Figure 2 presents the flow of the two methods.
Researchers [11] applied a subcritical water extraction using ginger pulp and peel as raw materials.This method is an alternative step to replace organic solvents (such as methanol).For example, methanol plays a role in extracting active compounds and is categorized as environmentally friendly.The results showed that the optimum extraction to obtain 6-gingerol and 6-shogaol was 130 o C for 10 min (yield =0.35±0.10mg/g) and above 130 o C for 20 min (0.15±0.03 mg/g), respectively.The increase in temperature and extraction time favours the recovery of both components in the pulp compared to the peel.However, this waste has potential in terms of extracting bioactive compounds.
Appropriate technology is one solution for MSMEs by applying the drying and extraction process methods.Optimizing the extraction of ginger extract against the dregs of raw materials is also the same.Another opportunity is that the extraction process is carried out up to two times with polar solvents.Of course, the quality grade of the extract is below the first extraction process.The solid waste has postextraction potential to be continued for further extraction, pyrolysis, or hydrolysis into its derivative products.

Conclusion
Providing further post-harvest processing of fresh ginger in extraction or drying is a transformation step into a salable product, along with increasing shelf life.This type of polar solvent is a challenge for MSMEs to obtain the main, meaningful, and bioactive components of ginger raw materials.Apart from that, implementing the prototype is also a solution for optimizing extract recovery.The solid ginger pulp will be directed to a different extraction process with the help of another research team in the laboratory.Ginger products for MSMEs have been able to contribute to empowering and producing an independent economy for the community.Hydrolysis and pyrolysis processes can be aimed at industries with certain operating conditions and higher selling prices.

FreezeDrying 1 .
Electric heating air blast dryer Dimension: 4 x 4 x 3 cm T = 50, 60, and 70 o C Velocity of hot air = 0.75±0.03ms -1 Single layer, 100 g per batch ginger slices for moisture content 5% (w.b.) Air Drying, AD Microwave oven 2455 MHz 3.5 x 3.5 x 2.4 cm Power = 0 -700 W with 0 -999 s or min.Single layer, 100 g per batch ginger slices with 60 W, for 5% (w.b.) Pre-Experiment P = 60 W, 320 min to 5% (w.b.) Microwave Drying, MD Vacuum drying oven 4.15 x 3.7 x 3.45 cm Single layer, 100 g per batch ginger slices Pre-Experiment P = 13.3 kPa at 60 o C for 490 min for 5% (w.b.) Vacuum Drying, VD Single layer, 100 g per batch ginger slices.Ultra low temperature refrigerator, -80 o C for 4 h Pre-frozen sample Dried in freezing dryer in vacuum degree; 0.203 kPa with condensor temperature (22 and -55 o C) Pre-Experiment Freeze drying = 29 h (for 5% w.b.) Storage for ginger was 15 o C → preleminary treatment through peeling manually 2. Chop into 2 mm cubes + liquid nitrogen → grinding → pulp 3. Mixed 1 g pulp + 0.2 g coarse granulated celite (30-60 mesh) + 20 µl standard of solution tridecane (for extraction efficiency, ρ = 3 mg ml -1 ) 4. Make density fluid = 0.680 to 0.935 g ml -1 5. Put sample into supercritical fluid extractor for 3 min (static condition) + dynamic extraction for 30 min with flow of 1 ml min -1 through a fused sillica back pressure restrictor 6. Extract + dodecane (20 µl of a standard solution containg 3,0 mg ml -1 →total mass of 1 g with pure CHCl3 Supercritical Fluid Liquid CO2 1. Dimension of pieces, pulp = 5 x 5 x 5 mm → stored at 4 o C for 4 days.Water content for pulp and peel = 83.7 ± 1.2% and 89.6 ± 0.3%, respectively 2. 1 g ginger pulp + purified water → extractor cell with volume of 22 ml containing a cellulose filter → oven →extraction through heating under pressure high pressure (~ 10 MPa) with water for 30 s 3. Extract + gas N2 and residual pressure for extraction cell → purging for 1 min → final extract → storage in a bottle 4. Sample → Dilution with an equal volume of methanol → Filter through 0.45 µm PVDF 13 mm filter → analysis sample Temperature and times extraction = 110-190 o C (with increment @ 20 o C) and 5g of freeze dried ginger powder + 10 kg crushed dry ice into inside a stainless-steel cylinder of glass Soxhlet extractor 2. In outside jacket, put propylene glycol and circulated (T= 45 ± 2 o C) as a heater 3. Pressure inside the cylinder increased and stabilized at 600-700 psi 4.After 49 h (time extraction), circulating pre-cooled alcohol (95%) in the outside jacket roled as cooling agent to -60 o C → 3.44% w/w, dry weight of a goldenbrown oil

Table 1 .
Volatile oil of ginger