Effectiveness of Biodegradable Plastic in Preventing Food Spoilage

Home , Plastic wrap, Polyethylene

E!ectiveness of Biodegradable Plastic in Preventing Food Spoilage Catherine R. Zhang1 and Jill Carter1 1Shrewsbury High School, 64 Holden Street, Shrewsbury, MA 01545

Summary: The purpose of this study was to compare 100% +HQFHLWLVLPSRUWDQWWRFRPSDUHWKHHIIHFWLYHQHVVRID polylactic acid (PLA) biodegradable plastic with a low- ELRGHJUDGDEOH SODVWLF LQ SUHYHQWLQJ IRRG VSRLODJH ZLWK density polyethylene plastic (LDPE) in terms of their WKDWRIDJHQHULFSODVWLF e!ectiveness against food spoilage. The interests of this )RRG VSRLODJH LV ZKHQ WKH RULJLQDO QXWULWLRQDO study were: 1) the type of plastic that is more e!ective YDOXH WH[WXUH RU ÀDYRU RI WKH IRRG DUH GDPDJHG DQG in preventing food spoilage, and 2) the materials’ properties, which are key factors in preventing food WKH IRRG EHFRPHV KDUPIXO WR SHRSOH DQG XQVXLWDEOH spoilage. Three trials were conducted testing the two WR HDW )RRG VSRLOV PDLQO\ EHFDXVH RI PRLVWXUH plastics, in which an apple half was wrapped in either R[\JHQ OLJKW DQG PLFURRUJDQLVPV 2[\JHQ FDQ KDYH 100% biodegradable plastic, LDPE plastic, or no plastic GHWHULRUDWLQJHIIHFWVRQIDWVIRRGFRORUVYLWDPLQVDQG at all (control). Over a period of 11 days, the daily mass of ÀDYRUVDQGFDQFUHDWHFRQGLWLRQVVXLWDEOHIRUWKHJURZWK the apple was measured to determine the type of plastic RI PLFURRUJDQLVPV 2[\JHQ DOVR FDXVHV R[LGDWLYH that was more e!ective in preventing food spoilage. The VSRLODJHZKLFKLVWKHPDLQFDXVHRITXDOLW\ORVVLQIDWV results showed that in the long term (11 days), the LDPE 2[LGDWLRQLVWKHORVVRIHOHFWURQV2[LGDWLRQQRWRQO\ plastic was more e!ective in preventing food spoilage VWDUWVWRGHJUDGHWKHDSSOH¶VQXWULHQWVEXWDWPRVSKHULF than the biodegradable plastic. By day 11, the apples in LDPE plastic lost about 4.84% of their original mass, the R[\JHQ FDQ UHDFW ZLWK VRPH IRRG FRPSRQHQWV ZKLFK apples in biodegradable plastic lost 18.25% of their mass, PD\ FDXVH UDQFLGLW\ RU FRORU FKDQJHV &HUWDLQ and the control apples lost about 56.11% of their mass. HQ]\PHVLQIRRGVFDQVSHHGXSWKHFKHPLFDOUHDFWLRQV However, in the short term (1-3 days), both the apples EHWZHHQ R[\JHQ DQG IRRG ,Q DSSOHV WKH VSHFL¿F in LDPE plastic and the apples in the biodegradable HQ]\PH WKDW FDXVHV WKH EURZQLVK FRORU WR DSSHDU LV plastic lost a similar amount of their mass (2-4%) while FDOOHGSRO\SKHQROR[LGDVH([SRVXUHWROLJKWFDQFDXVH the control apples lost about 20% of their mass. The IRRGVSRLODJHWKURXJKSKRWRGHJUDGDWLRQ GHJUDGDWLRQE\ results demonstrate that the biodegradable plastic can 89OLJKW LQWKHSLJPHQWVIDWVSURWHLQVDQGYLWDPLQVRI prevent food spoilage as e!ectively as the LDPE plastic IRRG ,Q VROLG IRRGV SKRWRGHJUDGDWLRQ RFFXUV ZKHUH in the short term. Hopefully, this will increase the appeal of biodegradable bags to consumers due to its ability to WKHOLJKWSHQHWUDWHVWKHRXWHUOD\HURIWKHIRRG,QOLTXLGV reduce the amount of trash in land"lls. OLJKWSHQHWUDWLRQFDQEHJUHDWHUEXWWKHOLJKWSHQHWUDWLRQ GHSHQGVRQIDFWRUVVXFKDVWKHOLJKWVRXUFHVWUHQJWKDQG 5HFHLYHG6HSWHPEHU$FFHSWHG1RYHPEHU WKHW\SHRIOLJKWHPLWWHG 3XEOLVKHG0DUFK ,QWKLVVWXG\WKHIRFXVZLOOEHRQH[DPLQLQJWKH LQÀ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¿OO SUREOHP ,Q WKH SDVW PXFK UHVHDUFK :UDS /'3( LV À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