If the chromic acid oxidation is performed with stoichiometric oxidant in the presence of diethyl ether as co-solvent (a method introduced by H.C. Brown), the epimerization of l-menthone to d-isomenthone is largely avoided.
Apple cider vinegar isn't likely to be effective for weight loss. Proponents of the apple cider vinegar diet claim that drinking a small amount of apple cider vinegar before meals or taking an apple cider vinegar supplement helps curb appetite and burn fat. However, there's little scientific support for these claims.
Apple cider vinegar helped me immensely during that time, until I got my digestion ironed out in other ways. Apple cider vinegar can help to support digestion by providing enzymes and certain acids. The enzymes help support those who do not produce enough enzymes on their own, an all too common issue in this modern day. Take some apple cider vinegar in water 15 minutes prior to meals to help get your digestive juices going (1 Tbsp. in a few ounces of water). This can help to prevent indigestion, gas or bloating.