During the last six months, draft results were presented at the AMGA conference in October 2022, an article was published in Mushroom Link, and a manuscript for submission to a peer-reviewed scientific journal prepared.

Key findings from Phase 1 included:

β-glucan content of Australian mushroom varieties compared to oats:

• In a freeze-dried sample, common mushroom varieties contained similar amounts of β-glucan to oats.
• However, because of mushroom’s high moisture content a significantly greater serving size is required to provide 1 g of β-glucan (the amount of β-glucan required in a serving of oats and barley products to allow a health claim) compared to oats and the amount of mushrooms commonly consumed by Australians.
• Serving sizes of 150–300g (4-7 mushrooms) of raw, 80–200g of cooked and 10-20g of freeze dried conventional Agaricus bisporus mushrooms provided 1g of β-glucan. Serving sizes to obtain 1 g of β-glucan from the most common variety, Button mushrooms, were approximately 6 mushrooms, 150g raw, 100g cooked and 10g freeze dried.
• Cooking mushrooms increased the amount of β-glucan.
• Considering the levels currently consumed by Australians (average of 60g/day for mushroom consumers). The daily serving size of fresh or cooked conventional Agaricus bisporus mushrooms needed to provide 1g of β-glucan may be challenging to achieve. However, the amounts may be feasible through consuming a combination of mushroom forms, including raw, cooked and freeze-dried forms. In addition, the target population may be willing to make certain dietary choices to improve or maintain their cholesterol levels.

Mushroom’s capacity to bind bile acids (the primary cholesterol lowering mechanism of β-glucan) compared to oats:

• β-glucan in button, cup, flat, and brown mushrooms had similar bile acid binding capacity (in other words, similar cholesterol lowering properties) to oat β-glucan.
• A clinical trial is needed to support these preliminary fundings and to strengthen the case for a cholesterol lowering effect of β-glucan from mushrooms.