BACKGROUND

Lipases are widely diversified in their enzymatic properties and substrate specificity. The need for novel lipases is obvious, and the industry continues to look for the high activity, less expensive sources, high selectivity and regioselectivity. New lipases with special properties are waiting to be discovered as Malaysia is rich in bioresources.

The applications of fats and oils can be broaden by changing their physical and chemical properties to suit the requirements of a product and may be brought the application of lipases. In the more developed nations, lipases have made significant in-road as the preferred catalyst in the fats and oil industry. This is partly due the specific nature of the enzyme, and partly to customer demand for more natural processes especially for the production of foods and food ingredients. In Malaysia, modifications made on palm oil and its fractions are still based on physical and chemical processes. Inclusion or replacement of these processes with biotechnology ones can enhance product diversification and the image of the Malaysian palm oil Industry. Some of the potential products that can be derived from reacting fats and oils with lipases are structured lipids
(e.g low calorie fats, fats for confectionery, fats for baking and frying ), oleic acid-rich lipid hydrolysate, diglyceride oils, emulsifiers such as monoglycerides, and low temperature stable oil especially palm oil that can withstand low temperature storage without turning solid.

Adulteration has been in the fats and oils industry for a long time. It is sometimes deliberate, sometimes accidental. Whatever it may be, it is the highly priced oils that undergo adulteration frequently. It is also a problem when oils are adulterated with lard, either for the purpose of adulteration or new product development, and where the consumption of lard is restricted by religion. Sometimes, fluid vegetables oils are also blended with animal fats, thus changing their nutritional value by making them more saturated. The problem of adulteration is compounded by the ability of catalysts, both metal and enzyme, to transesterify adulterated oil into a novel oil, thus making detection even harder. Lipase can be useful in providing a means of randomising adulterated fats, and then using these products to develop a database by which adulterated fats can be fingerprinted. Currently common analytical methods have been found wanting in terms of detection of adulteration.

OBJECTIVES

1. Bioprospecting, improvement and production of new lipases for oil modification
2. Applications of lipases for the nutritional and structural improvement of palm oil and its fraction to produce value-added oil products ( e.g oleic acid, low cloud point oil, diglyceride oil, monoglyceride).
3. Development of methods for the detection and quantification of adulterant oils in palm oil and its products.

METHODOLOGY

1. Bioprospecting , improvement and production of new lipases for oil modification.

• Screening indigenous sources for lipases producers microbes and plants - and including naturally immobilized lipases using specific isolation and detection media.

• Extraction of the lipases / stabilization of lipases.

• Characterization of lipases properties including specificity determination.

• Genetic and protein engineering may be involved in the improvement of lipases (construction of genomic library and PCR).

• Bioreactor production of selected lipases.

2. Applications of lipases for the nutritional and structural improvement of palm oil and its fraction to produce value-added oil products.

• Production and application of naturally immobilized lipases from microbial sources

• Enzymatic production of structured lipids such as low calorie fats.

• Enzymatic fractionation of palm oil into stearin and olien (alternative to physical/ chemical fractionation).

• Enzymatic production of monoglycerides

• Enzymatic production of unsaturated fatty acids oleic acid and linoleic acids though selective hydrolysis.

  
  

EXECUTIVE SUMMARY

Project Title:
Improving the functionality and nutritional qualities of fats
and oils biotechnological processes

 

• Applications of transformed fats / oils in food systems.

• Development of bioreactor system for lipases reaction.

3. Development of methods for the detection and quantification of adulterant oils in palm oil and its products.

• To develop methods for the detection and quantification of adulterant oils. These will include adulterated fats/oils that have been enzymatically and chemically interesterified to either change their characteristics or to disguise the presence of the adulterant or both. Methods that have been identified are HPLC, GC, DSC and FTIR.

• Comparison of different analytical techniques.

• To investigate the effect of both chemical and enzymatic modification of fats/oils blend on the ability to check adulteration.

• To analyse foods with animal fat adulteration.

EXPECTED OUTPUT

1. New lipases with required specificity and activity from indigenous sources.

2. Successful production of stable naturally immobilised lipase suitable for selective hydrolysis of oleic acid.

3. Databases on the physical and chemical properties of new oils and fats from local sources

4. Procedures for the optimum production of modified fats either through interesterification of selective hydrolysis.

5. Applications of some modified products in food systems.

6. Indicators for detection of adulteration.

Period of the project : 3 Years (2001 - 2004)

Progress/Achievements for 2002

New Products

• Palm oil wastes from 16 mills have been collected and successfully screened for lipase producers using palm olein, palm stearin, coconut oil, corn oil, soya bean oil or clarified butter (Ghee) as the carbon sources. A total of 52 isolates were found to be lipolytic, or which 25r were bacteria, 10 yeasts and the rests were molds.

• 10 sources of lipases have been studied for the synthesis of glyceryl acyl esters. The enzymes were used as is (as free lipase) or immobilized to different types of support matrices. All were found to be active in the formation glyceryl acyl esters.

• The present of structured lipids through interesterification of "manggis" seed oil and coconut oil as well as "langsat" seed and coconut oil.

New process

• Both natural and enzyme-transesterified lard was used as an adulterant in palm oil.

• The thermal profiles of both the lard types were compared to those of beef tallow, mutton tallow and chicken fat.

• The cooling and melting profiles of the mixtures are being compared and multiple stepwise regression analysis will be conducted to confirm indicator adulteration peaks.

• Pancreatic lipolysis will also be conducted to observe the changes in the palmitic acid content in the second position of the triacylglycerol structure.

• Fatty acid enrichment factor as well as substractive thermogram method will be analysed to confirm the methods used.

Patents filed - 0

Discovery - The presence of structured lipids.

Publication - 8

Project Status

- On-going