Effects of bagging on “Hanfu” apple aroma compounds

Bagging is a key apple production technology in China. Present research on fruit bagging has focused mainly on fruit micro-environment, structure, resistance capacity to adverse environmental elements, quality, etc. There has been less credible research on the effects of fruit bagging materials on fruit taste. Fruit aroma, a critical fruit taste indicator that determines fruit flavor, was investigated in this study in relation to fruit bag materials. The study used static headspace and meteorological chromatography- mass spectrometry technology to analyze the effects of bags of different materials (e.g., plastic film bag, double-layer paper bag, and reflective film bag) on aromatic compounds of “Hanfu” apple fruits. Although the effects of different bag materials on fruit aromatic compounds were different, bagging generally reduced the total content of aromatic compounds in “Hanfu” apple fruits. The total content of aromas in plastic film bagged fruits was slightly lower than that in non-bagged (CK) fruits (0.792 μg·g^-1). The total contents of aromas in fruits with double-layer paper and reflective film bags were 40.03% and 20.33% lower than that of CK, respectively. While bagging increased the total content of esters, it decreased the total content of alcohols and aldehydes. The aroma compounds of “Hanfu” apple characteristically contained 2-methylethylbutyrate, ethyl butyrate, 2-methylethylhexylbutyrate, ethyl hexanoate and hexaldehyde; all of which were ester aromas. The characteristic aroma compound of apple fruits with plastic film and double-layer paper bags was 2-methylethylbutyrate. While ehylbutyrate and 2-methylethylbutyrate were the characteristic aroma compounds of apple fruits with reflective film bags, 2-methylethylbutyrate and hexaldehyde were the characteristic aroma compounds of CK fruits. Fruit bagging limited production of important aroma compound (E)-2-hexenal, causing lower aroma quality of apple fruit under bagging than under CK conditions. The study of aromatic compounds laid the basis for research-driven selection and innovation of fruit bagging materials in fruit production.