Which one is better in terms of job opportunities among B.Sc in bio chemistry, nutrition and dietetics?

Both the course you mentioned have a good opportunity, it's all depends on you what you want to be, Salary depends in the company and experience and your performance.

Job opportunities for B.Sc in biochemistry: Students can pursue a career in Science and Technology where a high level of competence and dependence on many of the science subjects is demanded. Laboratory analyst in Pharmaceuticals and food industries. Research Analyst in the field of Biotechnology /