In acidic foods (with pH of 4.6 or less), such as fruit juice and beer, the heat treatments are designed to inactivate enzymes (pectin methylesterase and polygalacturonase in fruit juices) and destroy spoilage microbes (yeast and lactobacillus). Due to the low pH of acidic foods, pathogens are unable to grow. The shelf-life is thereby extended several weeks. In less acidic foods (with pH greater than 4.6), such as milk and liquid eggs, the heat treatments are designed to destroy pathogens and spoilage organisms (yeast and molds). Not all spoilage organisms are destroyed under pasteurization parameters, so subsequent refrigeration is necessary.
in aCidic FooDS (With pH oF 46 oR leSs) SuCh aS fRuIT juiCE And beer ThE heAT treaTMentS aRE DESIgnED tO inaCtIvate EnzymES (PeCtiN meThylEsterAse and poLygalacturonaSe in fruiT juiCES) and dEsTRoy spoILagE MiCrOBes (yEaSt and LacTobAciLlus) DuE to ThE lOw Ph of AciDIc foods paThogenS are uNaBLe To GrOW The shelf-LifE Is tHERebY Extended seVeral Weeks in LeSS acIdic fOods (witH pH greAter than 46) SuCh aS miLk and lIquid EGgs The HeaT trEaTMents are deSigned tO DeStRoy pathogeNs ANd spoilage orGANIsMs (yeast aND moLds) NOt alL SpoIlAgE ORganisms are dEstroyED undEr pasTeUrizAtion PaRAMeters so subsequENt refRIgeraTion iS NeceSsAry