Abstract:

The effects of three postharvest gas impingement treatments on fruit quality of strawberry were analyzed using
multivariate analysis. The results showed that nitrogen treated strawberry revealed a downward trend for the quality, flavor,
aroma, color, hardness and sweetness/acidity at room temperature. Ozone treatment resulted in the delay of quality deterioration
for strawberry, and a downward trend in sweetness/acidity, aroma, stiffness, acidity and firmness at low temperature. The quality
of the strawberry treated with carbon dioxide was corrupted significantly and revealed a sharp fall in sweetness, firmness, flavor,
aroma and total acid of strawberry during storage. The results of principal component analysis (PCA) showed that pH, L*, a*
and b* values, soluble solids content (SSC), sweetness and firmness were affected mainly by carbon dioxide treatment, whereas
acidity, protein and color were affected mainly by nitrogen treatment at room temperature. The changes in the ratio of soluble
solids content to total acid (SSC/TA), quality, flavor, aroma, total acid and sweetness/acidity in the strawberry subjected to
carbon dioxide treatment were more obvious at low temperature, but carbon dioxide treatment could result in the worst storage
quality of strawberry fruits. PLSR and path coefficient analysis showed that flavor revealed a highly significant correlation with
quality, and was that main function index that could affect the quality of strawberry fruits and had an indirect effect on quality
by firmness and protein. In contrast, fruit quality had an indirect effect on flavor by SSC, SSC/TA and total acid.

Key words: strawberry, gas-shock treatment, fruit quality, multivariate analysis