Xws li qab zib, ntxoov ntxoo, turbidity, mellow, astringent thiab iab, tshav kub, thiab muaj los yog tsis muaj ntxhiab tsw phem xws li deterioration, sourness, rot, pa luam yeeb, mildew, thiab lwm yam. Cov saj ntawm ntsuab tshuaj yej, zoo li nws aroma, txawv nrog cov qhov chaw ntawm keeb kwm thiab hom tshuaj yej. Feem ntau hais lus, lawv qab zib thiab meej, thiab tuab thiab mellow. Cov saj tsis muaj zog, thiab iab thiab pungent sawv daws yuav tsis yog qib siab. Qee cov tshuaj yej ntsuab muaj iab me ntsis, tab sis lawv yuav tsum iab thiab qab zib. Lawv muaj qhov saj ntawm cov pa luam yeeb nyom, qaub, thiab pythium scorch. Los yog cov neeg uas raug kev txom nyem los ntawm loog loog thiab loog, tsis yog qib siab. Thaum txheeb xyuas qhov saj, qhov nkag ntawm cov tshuaj yej kua zaub yuav tsum tsis txhob ntau dhau. Cov tshuaj yej kua zaub yuav tsum tau tig los ntawm ib lub sij hawm nyob rau hauv lub qhov ncauj, kom lub voj voog nce mus, nqis, sab laug, sab xis, pem hauv ntej, thiab rov qab ntawm tus nplaig. Tus nplaig hnov qab zib thiab ntsim, tus nplaig hnov qaub ntawm ob sab, lub hauv paus ntawm tus nplaig hnov iab, thiab tag nrho tus nplaig hnov qab ntsev. Tsuas yog los ntawm kev ncav tag nrho tus nplaig tuaj yeem peb paub qhov txawv ntawm txhua qhov saj ntawm tshuaj yej.
