Frankly, Im not going to take the time and dig through 50 years of WBC and MBAA material to find the papers. If you want to pay the 65 bucks for each WBC year, the material is there. That said, look at the Wallerstein papers on antioxidants and the dozens following from it, then go to the Molson/Miller work where they tested various antioxidants on aged and fresh beer. In short, antioxidants, including SMB, do have a positive effect on beer staling, but the effect is generally short lived and can cause issues with sulfur interaction with some beers. Moreover, early antioxidant studies were conducted mostly for the sake of pasteurized beer, where consumers would be drinking product up to a year after packaging. I dont know many home brewers who pasteurize their beer, nor those who cannot gain more antioxidant benefit from having live yeast in their beer. I dont claim to be an expert in DO/antioxidant use, but Ive been in the industry long enough to know what is relevant to brewers less than 100,000 bbls.
Moreover, low DO mashing (not splashing, ect) is good practice, but adding SMB is not necessary for home brewers; it use skirts the more important issues like fermentation, storage, and packaging process. I think it was the Straub antioxidant paper (1989?) where it was determined that poor brewing practices negate almost all the effects of antioxidant use. If you cant brew technically proficient beer to start, antioxidant use will not fix the base problems.
IMO, ascorbic acid and tannic acid (brewtan, ect) would be a safer and more practical antioxidant than SMB, especially when brewing Helles, where brewers go to great lengths to avoid adding sulfur to their brews.
My initial problem with the paper posted, was the almost complete lack of citations/source material. Moreover, these gems:
You cannot make a proper Helles without employing a low oxygen brewing process.
Please explain what a proper Helles is. Ive been to many German and American breweries who make acclaimed Helles and many of them do so without SMB or intensive low DO brewing practices. In fact, most of them have good process control and mitigate DO through basic, proper brewing practices. Augustiner?
Moreover, please quantify fresh malt flavor. Is there an ASBC method I can use to measure what this is? How will I know Ive lost it in the brewery when we measure our wort DO and its above 1ppm. Where is the evidence for this? Source material?