In his days as a jet-setting telecom executive, ready-to-eat meals were a regular part of Fazal Bahardeen's luggage. Many of the hotels he stayed in did not have halaal-certified restaurants for Muslim travellers like the 47-year-old Sri Lankan-born Singaporean.
Rooms lacked markers pointing to Mecca for prayers and staff were unable to answer questions from Muslim guests about their particular needs.
"Half of my life was spent in hotels and airplanes," Fazal told AFP.
"But being a Muslim, I was getting frustrated by the travel industry or the hotels not being able to provide the right services. You don't know what the prayer time is, where the prayer direction is, and you can't find halaal food."
But halaal travel is now gaining popularity as demand for products and services permitted by Islam extends beyond food and interest-free financial instruments, and affluent Muslim travellers make their influence felt.
Halaal travel is expected to be worth $100-billion annually within two years, said Fazal, who resigned from a senior management job at a major telecom firm in 2006 and set up his own company to tap into the expected boom.
Fazal's Crescentrating Pte Ltd is believed to be the only company in the world that rates hotels globally for their friendliness to Muslim travellers.
Its online booking portal ? www.crescentrating.com ? also promotes halaal tours.
Travel commentator Yeoh Siew Hoon told AFP there is a real demand for halaal travel, led by tourists from Southeast Asia and the Middle East.
"Take Indonesia ? it is one of the fastest growing outbound markets in Asia, and is the number one source of visitors to Singapore," said Yeoh, who operates an industry website www.webintravel.com.
Chinese Muslims an untapped market
"Tourism Australia also produces a guide to halaal restaurants due to the growing numbers of travellers from Muslim countries," she added.
Greg Duffell, chief executive of the Bangkok-based Pacific Asia Travel Association (PATA), said China's sizeable Muslim population is another potential source of outbound travel.
"A lot of suppliers are now amending their products to meet halaal standards," Duffell told AFP.
"It is a trend that started a few years ago. Since then, restaurants and resorts in Singapore, Thailand and Vietnam too have begun adapting their standards, so it's beginning to branch out," he said.
"There are more designated halaal restaurants in hotels now, and prayer facilities on the premises, especially at the airports."
Crescentrating's hotel grading system ranges from one to seven and is based on the availability of halaal food as well as prayer rooms and mats ? and the non-availability of forbidden items like alcohol and adult TV channels.
A rating of one is given to a hotel with no such facilities but whose employees are trained to answer questions from Muslim guests.
This can be raised a notch if the hotel has a list of halaal-certified restaurants in its vicinity ? even if it does not have one itself.
Wealthy Muslim travellers driving growth
The company's highest ratings, six and seven, require a hotel to be free of alcohol, discos and TV channels showing movies unsuitable for families and children. In addition, all food and beverages must be halaal.
Globally, only Dubai's Al Jawhara Garden Hotel has a rating of seven, while three hotels in Saudi Arabia and one in South Africa are rated six.
The halaal food industry is worth $600-billion to $650-billion a year, according to Fazal and industry reports.
Islamic finance meanwhile boomed when Muslims began to look for investments approved by their religion, and the sector has attracted non-Muslims too after the global financial crisis.
"The halaal consciousness is rapidly going beyond food and finance," said Fazal, arguing that with 1.6 billion increasingly wealthy Muslims worldwide, halaal-friendly travel is likely to be the next growth area.
Muslim travellers account for seven to eight percent of global tourism expenditure, which totalled around $930-billion in 2009, up from just three-four percent 10 years ago, Fazal said.
This share is expected to expand to 10 percent in the next two years.
Crescentrating also hopes to stamp halaal-friendly ratings on theme parks, convention venues, cruise ships, shopping malls and hospitals used by medical tourists.