JELLIES are among the ever-growing list of popular Malaysian foods, especially in restaurants and at home parties. Other than the conventional agar-agar and fruit jelly, herbal jelly and konnyaku jelly are well liked. Besides being high in calories due to the added sugar, what are the health issues regarding these jellies?
Technically speaking, sweet jelly is prepared by boiling fruit juices with sugars, with or without adding pectin as a gelling agent. However, cooking with pectin requires a certain technique, otherwise the jelly would turn out lumpy. Furthermore, the jelly needs to be refrigerated for gelling and maintaining a firm texture.
On the other hand, cooking with agar-agar is simpler. It melts into a gelatinous, thick liquid that firms up when set, even without refrigeration. It will not melt unless it is reheated. This has led to the popular use of agar-agar as a gelling agent in home- and restaurant-cooking. Because of the similarity in texture to real jelly and agar-agar, “jelly” has become the common local name for these desserts.
Crinkly strips of dried agar-agar are usually packed in long cellophane packets; refined agar-agar powder comes in smaller sachets. They are made from seaweed, usually of the Gelidium amansii variety. The main component in agar-agar is the polysaccharides from the cell walls of the seaweed. It has lots of fibre that contribute to the laxative property of agar-agar.
In Asia, the Japanese consume the most seaweed. They make agar-agar into large, square sticks known as kanten. Researchers in Japan have shown that a combination of kanten with the conventional traditional Japanese diet is effective in helping people to lose weight since eating kanten makes one feel fuller and that makes one inclined to eat less during a meal.
The high-fibre kanten is also beneficial to patients with impaired glucose tolerance and Type 2 diabetes. The fibres help to slow absorption of sugar components that may be present in food.
In local practice, adding santan, pandan extract, chocolate, soy, almond or synthetic essences and colours has resulted in great varieties of agar jellies. The dessert is often sweetened with plenty of sugar. Taking sweetened agar as a dessert adds more calories that lead to weight gain. If one is on a weight management plan, a better practice is to eat unsweetened agar-agar at the beginning of a meal. This may help to take the edge off one’s appetite.
Besides jelly desserts, one can find agar-agar in other dishes. Soaked agar-agar strips have a texture similar to bird’s nest. So, some people use it to bulk up the expensive bird’s nest drink. Agar-agar is also used in preparing savoury foods, such as chicken in a cold dish. You may be surprised, too, to know that agar-agar is a basic culture medium set at the bottom of the petri dishes for microbiological work in laboratories.
Nowadays, with the use of carrageenan, manufacturers offer consumers many varieties of commercial jelly products on grocery store shelves. Pectin, which is extracted from plants, and gelatine from animal bones are other gelling additives used commercially, but to a lesser extent in recent years.
Similar to agar-agar, carrageenan is also a seaweed extract but has different chemical components than those found in agar-agar. Carrageenan contains polysaccharides made up of D-galactopyranose and the agar polysaccharide is made of galactose. In addition to the red algae Chondrus crispus, other species such as Gymnogongrus, Eucheuma, Ahnfeltia and Gigartina have been used for the production of carrageenan.
Carrageenan is a food additive that functions as a thickener, stabiliser and texturiser in a variety of processed foods. It is cost-effective and its good gelling properties have paved the way for its use in jelly production.
Early research has caused some confusion about the properties of carrageenan. According to an article in Environ Health Perspect, 2002, a researcher found unfavourable health effects including colonic ulcerations to experimental animals fed with degraded form of carrageenan, while the undegraded carrageenan was found to be safer.
The degraded form of carrageenan was later named poligeenan, which is intended for industrial use. The undegraded food grade carrageenan has a lower level of contaminants than poligeenan and is safer for consumption. The food industry should only use the food grade to manufacture food that is safe for human consumption.
Carageenan is grouped as a food additive with GRAS (Generally recognised As Safe) status and sometimes labelled as E407 or seaweed extract. However, there is no absolute safety with regards to the consumption of food additives, so eating in moderation is the key.
Cincau and konnyaku jellies
Herbal jelly, known as cincau locally, is also known as grass jelly, xiancao or leung fann. Pure cincau extract is made from the Mesona plant that is related to the mint family. Common varieties used are M. pelustris, M. procumbens Hemsley and M. chinensis.
Pure cincau extract is made by boiling the Mesona plant with some alkali such as potassium carbonate. It cools into a jelly-like texture and is dark green to black in colour. It contains vitamin A, calcium and iron. The Chinese regard it as a “cooling” food.
Nowadays, pure cincau extract is hard to come by. Most commercial cincau jelly is made by adding carrageenan to the pure extract. Cincau jelly cubes or strips are often served in combination with ice kacang, cendol or soybean drink.
Another jelly ingredient is made from the corm (underground root) of snake palm, or elephant yam that belongs to the genus Amorphophallus. The refined extract is known as konnyaku, konjac or yam flour. It is the glucomannan from the elephant yam that gives the firmer gelling properties of konnyaku.
Konnyaku gel does not dissolve readily in the mouth. Jellies made of konnyaku pose a high risk of choking, particularly to infants, children and the elderly. It is safer if the jelly is cut into smaller serving portions before it is consumed. Chia Joo Suan is a food chemist who advocates safe eating habits.
Do you have questions on food safety? Send your queries to:
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