Diet Tips:Talking tofu

By Dr Jane Varney

There’s been a lot of discussion regarding the FODMAP content of tofu recently, so we're going to clear up some of the confusion!

Also known as bean curd, tofu is a nutritious and versatile food that features heavily in vegetarian and Asian cuisines. Made by coagulating soy milk and pressing the curds into block moulds, it is low in fat, low in kilojoules and high in protein, making it a healthy addition to any diet. 

There are a wide range of tofu varieties on the market that vary in moisture content and texture. Typically, firmer varieties have had more water pressed out of them, while softer varieties are either unpressed or have had less water pressed out of them.

 

Silken tofu is unpressed and has the highest water content, making it a suitable addition to creamy foods such as smoothies, desserts, sauces, and dips. It is often used as a substitute for eggs in baked dishes. Firmer varieties of tofu have a lower water content and can be sliced, baked, fried, stir-fried or scrambled.

But what is the FODMAP content of tofu and how much can safely be included in a low FODMAP diet?

The answer to this question depends on the variety of tofu in question. Our analyses have revealed that silken tofu is high FODMAP in a 140g serve, due to the presence of oligos (GOS and fructans), whereas firm tofu is low in FODMAPs in a 170g serve.

Tofu, firm, drained	Serving size	Rating
1 serve	170g (⅔ cup, cubed)	Low
½ serve	85g (⅓ cup, cubed)	Low
Tofu, silken, drained
1 serve	140g (⅔ cup)	High
½ serve	70g (⅓ cup)	High

 Why the difference, we hear you ask? We think it is due to differences in food processing methods. As you might remember from previous blog posts, FODMAPs (particularly fructans and GOS) are water soluble, so drained, firm tofu (with a lower water content) is lower in FODMAPs than silken tofu that has a high water content.

The take home message: drained, firm tofu is a nutritious, low FODMAP source of protein that can be enjoyed in Asian and vegetarian dishes. 

Check out our tofu recipes included in the app and previous blog posts:

Marinated tofu recipe

Scrambled tofu recipe

Vegan, gluten free french toast

Diet Tips:UPDATE! Newly tested foods: the mysterious case of the guava

By Lyndal McNamara (APD)

 

If there is one thing that we have learnt regarding FODMAP testing here at Monash University, it is that there are a HUGE number of factors that can influence the FODMAP content of a food. This is why it is very difficult to decide whether a food is high or low in FODMAPs simply based on an ingredients list. Different food processing methods in particular can influence the FODMAP content of a food.

The classic example here is sourdough spelt bread, where spelt flour by itself is a high FODMAP food, the sourdough fermentation process used to make it into bread results in the end product being low FODMAP. In the same way, the natural process of ripening can affect the FODMAP content of certain fruits.

We recently tested guavas for our app and made an interesting discovery when both ripe and unripe guavas were tested. Our testing found that whilst a serve of well ripened guava was low in FODMAPs, an equivalent serve of unripe guava was high in FODMAPs. The ripening process therefore results in an overall reduction in the total FODMAP content of guavas.

The opposite is true if we consider sugar bananas, where the ripening process results in a total increase in FODMAP content. This is just another reason why the food testing we do here at Monash University is so important, as we know that different foods behave very differently in terms of FODMAPs, even when they are subject to the same processing methods/natural conditions.

So now that ripe guavas have been given the green light, you can enjoy the following recipes for making guava jelly (jam) and guava and rosemary glazed chicken breast. Guava jelly (jam) is a delicious traditional Columbian food that can be used as a low FODMAP alternative to quince paste with your favourite cheese, spread on toast or used as a fantastic marinade for chicken, duck or turkey. 

Guava jelly (jam)         ............................................................................................. INGREDIENTS 500g ripe guava  ¾ cup white sugar  1 cup water  1 lemon, juiced    .............................................................................................. METHOD   1. Wash and top and tail fruit (do not peel)  2. Cover fruit with cold water in a saucepan. Boil until very soft  3. Mash and sieve twice to remove pulp. Discard pulp  4. Add sugar and lemon juice, boil uncovered for 45 minutes  5. Pour jelly into sterilised jars and seal.

Guava and rosemary glazed chicken breast          ............................................................................................. Serves: 4 ..............................................................................................   INGREDIENTS 1 lime, juiced 2 sprigs fresh rosemary  2 tbs. garlic infused olive oil  750g skinless chicken breast fillets  Freshly ground salt and black pepper, to taste 1/3 cup plain, gluten-free flour    .............................................................................................. METHOD 1. Preheat oven to 200 degrees. Line a baking tray with baking paper and set aside. 2. In a small saucepan, over medium-low heat, combine guava jelly, lime juice and rosemary sprigs. Heat until the mixture reaches a liquid consistency. 3. In large frying pan, over medium-high heat, heat oil. Season chicken breasts with salt and pepper. Coat seasoned chicken in flour and place in hot pan. Cook chicken for 5 to 10 minutes per side or until cooked through.  4. Transfer chicken to baking tray. Pour guava mixture into two small bowls. Generously brush guava mixture from first bowl over chicken breasts. Cook in oven for 10-15 minutes or until guava glaze begins to caramelise. Slice chicken breasts and divide onto 4 serving plates.  Brush chicken with guava mixture again from second bowl prior to serving. Serve with low FODMAP roast vegetables or salad.               .............................................................................................. NUTRITION INFORMATION per serve Energy total Protein Fat total          - Saturated      Carbohydrates Sodium 1764KJ 41.4g 20.6g 4.6g 17.1g 115mg (if salt not added to recipe)