Question: who discover the role of yeast in fermentation
[{'answer': 'Louis Pasteur', 'provenance': [{'wikipedia_id': '34385', 'title': 'Yeast', 'start_paragraph_id': 7, 'start_character': 31, 'end_paragraph_id': 7, 'end_character': 44, 'bleu_score': 1.0, 'section': 'Section::::History.\n'}]}, {'provenance': [{'wikipedia_id': '34385', 'title': 'Yeast', 'start_paragraph_id': 7, 'start_character': 0, 'end_paragraph_id': 7, 'end_character': 374, 'bleu_score': 0.8695211776073061, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 14494670650058010515}, 'section': 'Section::::History.\n'}]}]