Does processing soy lessen its nutritional benefits?

Scientists from Unilever and Wageningen University and Research have reported that they have discovered processing soy doesn’t decrease its protein nutritional quality. This means that soy can be a valuable source of protein in plant-based foods.

Lately there has been some concern about the nutritional content of plant-based foods so the scientists studied processed soy, which is an ingredient used in Unilever’s Vegetarian Butcher range and ice-cream products.

Soy is a common ingredient in plant-based foods because of its high protein content and quality. But you can’t simply add soybeans in their natural form to a plant-based chicken chunk or an ice cream, for example. Before being used, they must undergo processing, which can take various forms including soaking, heating and dehulling.

To better understand the effect of processing on protein quality, the study assessed the digestibility indispensable amino acid scores (DIAAS) — the UN Food and Agriculture Organization’s standard measure — of various products. The higher the score, the better the protein source fulfils our body’s requirements, with a score of 75 or above considered good.

Analysis of the data showed different protein quality scores between soy product groups, but the DIAAS score for soy protein concentrate — the most commonly used in food such as plant-based meat from The Vegetarian Butcher — was 88, which is slightly higher than the initial soy bean (which scores 85).

This research study found that the soy ingredients that Unilever uses in its plant-based food products are a good source of protein and just as good as the protein quality of soybean.

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