According to Associate Professor Dr. Nguyễn Duy Thịnh, former lecturer at Hanoi University of Science and Technology, borax was once commonly used in the food industry because of its preservative properties. It helped foods maintain freshness for longer periods, prevented spoilage, and enhanced elasticity and crispness. In the past, many food producers added borax to traditional dishes such as bánh đúc to increase firmness, or used it in bánh cuốn and rice noodles to improve texture and overall mouthfeel.

However, scientific studies have shown that borax is a toxic chemical that can pose serious health risks when consumed over a long period of time. Regular intake may negatively affect memory and cause damage to the nervous system, particularly in vulnerable groups such as children and the elderly. Recognizing these dangers, Vietnam has officially banned the use of borax in food processing in any form. Despite this strict regulation, in reality, some food producers still secretly use borax to enhance the chewiness and crisp texture of products such as giò and chả (Vietnamese pork rolls), as well as other processed foods, in order to attract consumers.

How to Identify Giò and Chả Containing Borax

Based on Taste and Aroma

Borax-free giò has a natural, pleasant aroma and a mildly sweet taste, leaving a gentle aftertaste after eating. Its texture is soft and moist, without being dry, crumbly, or overly firm.

If the giò has an unusually strong fragrance or an abnormally chewy texture, it may have been treated with borax or other artificial additives.

Sensory and Texture Examination

When pressing giò or chả with your fingers, if the product feels excessively hard, lacks elasticity, or is difficult to indent, it could be a sign of borax usage.

Observing the Cross-Section After Slicing

Borax-free giò usually contains small air holes formed during the steaming process. In contrast, giò containing borax often appears unnaturally smooth and dense, with almost no visible air pockets.

If you gently pull both ends of a slice and find it extremely stretchy and difficult to tear, this may indicate the presence of borax.

Cutting Test with a Knife

When cutting giò that does not contain borax, the knife typically encounters slight resistance, and the surface may feel mildly sticky.

On the other hand, giò containing borax is much easier to cut. The knife glides smoothly due to the unusually slick and dense texture of the product.

Turmeric Paper Test

You can also use turmeric paper—made by soaking absorbent paper in fresh turmeric juice and drying it—to test for borax. Press the paper gently against the surface of the giò. If, after about one minute, the paper changes color from yellow to orange-red, it indicates the presence of borax. It should be noted that this method is qualitative only and does not determine the exact amount of borax present.

Choosing Safe Food Products

To avoid purchasing giò and chả that contain borax, consumers are advised to buy products from reputable manufacturers with clear food safety certifications. Trustworthy producers often publicly commit to not using borax or harmful additives, prioritizing consumer health and complying with food safety regulations. Making informed choices not only protects personal health but also helps encourage safer and more responsible food production practices.