People in the private and public sectors are working overtime to discover the endless opportunities that Kashmir’s famed walnut offers. If the nut is managed properly, it can fetch more money than its kernel, Tahir Bhat and Hilal Shah reports
With apple dominating Kashmir’s horticulture basket, all other fruits are off the attention. Not many people know that the major interventions have taken place in the Walnut, one of the key dry fruits that have an estimated turnover of Rs 500 crore, a year.
Jammu and Kashmir continue to be India’s main walnut producing regions, with the production of around 2.66 lakh metric tonnes on 89,000 hectares of land. The consumption of walnut in India is too huge and it is a major walnut importer from the US and Chile. At the same time, however, part of the Kashmir produce is exported to Europe and the Middle East. The fruit being a major source for reducing “bad” cholesterol in human bodies, it is hugely in demand and that is the key factor for major market appetite.
Walnut continues to be the only organic fruit that Kashmir produces. Its plantation takes place on land that cannot be used for any other crop. It does not require any fertilizer or pesticide. With a longer gestation period, it takes a long time to bear fruit but once it does it continues production till the owners decided to sell its wood, a prized input for high-end furniture.
The fruit, at the time of harvest, has three ingredients of which the kernel is the only edible thing. The entire economy of Kashmir walnut is around the kernel though it sells the walnut and its kernel separately. The fruit has outer green covering called juglone and then the shell, or the husk of it, which needs to be broken to get the kernel out.
For the last many years the innovators and scientists are working on the two outer things to make them usable.
However, the major intervention, so far, has been on breaking the shell because it takes a lot of time to break the husk without damaging the kernel. Manual walnut cracking is labour-intensive, time-consuming and expensive. This intervention came from the private sector when a south Kashmir commoner started working on it and eventually succeeded in creating a walnut cracker, a machine that has the capacity to break 90 kgs of walnut an hour. For this machine, he got a patent as well.
Mushtaq Ahmad Dar’s cracking machine is quite popular and has sold almost 10 pieces for Rs 35000 each. “It does require some interventions and improvement,” Mushtaq Ahmad said. “Right now, with the support of National Innovation Foundation, the National Institute of Technology (NIT), Bangaluru s working on it.” He said the different size of the fruit is the major challenge and once this improvement takes place, it will be quite a hit.
Dar’s cracker pushes in walnut from a hopper to a motorized pulley system having two rollers running parallel to each other. These rollers crack the walnut without damaging the kernel. The prototype, however, damages the kernel in case the nuts in the process are of different sizes.
Ever since Dar got a patent for his machine in 2009, he has sold only 10 machines. “We have not marketed it on a major scale because it has to be perfect,” Ahmad said. “Once that happens, it will change the walnut processing.”
The Hull Tension
But before reaching the shell, the growers have to manage the juglone. It is equally time consuming and normally requires a lot of time to soften it so that it is peeling manually. “Before de-hulling of walnut the hull needs to loosen first, so the growers assemble the walnut and dump it in heaps,” said Dr Zamir Ahmad, who heads the Food Science and Technology department at the SKUAST. “After 10 to 12 days, the hull gets loosen and is manually separated.”
Normally they wash the fruit and then sundry it before cracking to extract the kernel. Dar intervened in the same machine and used food grade aluminium rollers to peel the fruit. The process in the two machines is the same but these are two different machines that are covered by two different patents.
As the cracker is undergoing improvements, the peeler is quite a hit.
Dar’s two interventions have reduced the labour costs by around 70 per cent and saved huge time. People took some time to understand the system and once they understood, the orders are flowing like water. Dar has entered into an agreement with an agriculture marketing company in Srinagar that sells one of its machines.
“To be honest, the peeler is hugely popular,” Mushtaq said. “Since 2012 when the prototype was made, we have sold 66 machines. This year alone, we sold 50 machines and right now we have orders in hand for a supply of 60 more.” Dar’s peeler costs Rs 20,000.
Once the hull is separated, the washing process is quite expensive and labour intensive. SKUAST’s Zameer Ahmad said they have estimated that almost three to 3.5 per cent of the de-hulled fruit is washed away in the process as the people use wicker baskets for the process.
This led the SKUAST experts to work on it. “To avoid this loss, we have discovered walnut de-huller,” Zameer said. “The machine washes as well as de-hulls 4 to 4.50 kg walnuts per hour.” His department has provided 25 such machines to growers. The machine, however, is expensive – it costs Rs 1.5 lakh, a piece.
De-hulling is crucial in the entire process. If a small amount of the hull secretions gets into the kernel, the quality nosedives and fetches less price. The hull must completely be cleaned from the shell to ensure the quality of the kernel.
“In this context, we have standardized a process which is known as Ethephon process through which we spray Ethephon 0.3% to walnuts,” Zameer said. “After the spray, we need to cover the walnuts and four days later our jobs get done”. The use of Ethephon, a plant growth regulator, advances shell-split.
Traditionally, people opt for sun-drying. Experts have been advising that the nutritious kernel is quite sensitive to heat. They have been suggesting the use of solar driers that work at a temperature between 40-45 degrees but this would require some time to get popular. In fact, the absence of solar driers is the key issue.
The walnut hull that usually is sun-dried and used as fuel in peripheral kitchens is a key component, experts say. It contains a component, 15 hydroxy naphthalene diode which is technically known as juglone or dye-juglone.
There are processes that help get organic dyes out of the hull. In Kashmir, it might take time and the processes might be expensive but it is possible.
However, what is new on the walnut front is the use of the shell in making activated carbon, a costly material that is used for various things in industrial processes. “The price of activated carbon is much higher than the walnut kernel,” Zameer Ahmad said. “It is used for filtration of water and medicine purposes. Its costs around Rs 6000, a kilogram.”
The activated carbon is used across the sectors in medical, ecological and manufacturing processes include methane and hydrogen storage, air purification, solvent recovery, decaffeination, gold purification, metal extraction, water purification, medicine, sewage treatment, air filters in respirators, filters in compressed air, teeth whitening, production of hydrogen chloride and many other applications.
While SKUAST is working on the issue, it remains to be seen how fast will they be able to offer solutions for use on a mass scale. If that ever happens, the walnut might be grown more for shell than for the kernel. China has stopped burning most of the walnut shells, reports appearing in the media said.
For Kashmir, however, the harvest remains untreated. Walnut harvesting is one of the nightmarish exercises for people because every year not less than a dozen people fall from the trees. These falls have only two outcomes – either death or crippling injury in the spinal cord. The harvest involves a man climbing up the slippery tree and using laanz, a long stick to beat the branches as a result of which the walnuts fall. While managing a firm grip and beating the branches, a slip costs a life.
SKUAST’s Zameer Ahmad said they have evolved two options. “Almost four to 4.5 per cent of the walnuts are lost every year because they fall and roll and reach places where they cannot be retrieved,” he said. “To prevent this loss, we have suggested the use of a particular net which is tied under the tree to collect walnuts at the time of plucking”.
On the actual harvesting part, Zameer said they have devised a process envisaging the use of vibe rope. Part of the rope is attached to branches and on the other end, it is shaken manually or by a tractor. The issue is that for tying the rope, one still has to be on the tree!