The factors that can affect the quality of sweet potatoes are insect infestation, diseases, physical and pest damage, skin marks, physical disorder, and temperature injury.
- Live insects or insect infestation: if sweet potatoes are not packed with betel, insects will come in and ruin the sweet potatoes and affect the sugary quality
- Disease: fungal or bacterial rots (e.g., Rhizopus rots, Erwinia, black rot)
- Physical and pest damage: holes or splits from physical or pest damage (e.g., tunneling from weevils) or cracks or badly disfigured tubers (nematode damage)
- Physical defect: growth cracks (moisture extremes), excessive veining, or a dry or woody fibrous core separating from the flesh (hardcore), skin marks with deep-seated bruises
- Temperature Injury:
- Internal discoloration, softening, or breakdown (chilling injury)
- Sprouting, stem end deterioration or softening (high humidity and temperature damage during specific growing periods)