I had the same problem for quite some time and it put me off making my own until a butcher at Sloans in Bryanston told me a secret I am thankful for every time I make biltong and wors. He told me to invest (and I say invest because it's morse expensive) in the best quality Red Wine vinegar I could afford. I went to Woolies and bought an imported bottle that set me back more than the meat cost on that day but the result is my biltong now has the most delish red wine taste and smell to. It's subtle and sweet and really made a world of different. I don't soak it for hours, I paint it onto the individual pieces 2/3 times while marinating and I'm gentle with the salt too cause I hate Biltong so salty it burns your tongue and make it feel like a piece of raw meat. I buy a premixed biltong spice mix at Spar, I can't remember the name right now but it comes in various flavors and I spice with that. Except skinny wors to make droe wors, with that I simply buy the best quality thin flavored wors I can and paint it with the high end vinegar a few times. Sloans makes a apricot and red wine wors that a fav with all.