WJEC Level 3 Diploma In Food Science And Nutrition
59 Butter %XWWHU FRQWDLQV OHFLWKLQ ZKLFK NHHSV WKH HPXOVLRQ VWDEOH ,Q GDLU\ PLON WKH WLQ\ IDW GURSOHWV EXWWHUIDW LW FRQWDLQV DUH VXVSHQGHG LQ D ZKLWH OLTXLG FRQWDLQLQJ SURWHLQ ZDWHU FDUERK\GUDWH PLQHUDOV DQG YLWDPLQV :KHQ IUHVKO\ FROOHFWHG GDLU\ PLON LV OHIW WR VWDQG LQ D FRROLQJ WDQN WKH IDW GURSOHWV ULVH WR the top of the milk as a layer of cream. 7KH WUDGLWLRQDO PHWKRG RI PDNLQJ EXWWHU LV WR skim WKH FUHDP Rʏ WKH PLON ZKLFK OHDYHV VNLPPHG DQG VHPL VNLPPHG PLON GHSHQGLQJ RQ KRZ PXFK FUHDP LV VNLPPHG Rʏ Modern methods use centrifuges to extract the cream. The cream is then churned (continuously stirred) until the droplets of fat collide and start to stick to each other. $V PRUH RI WKH IDW GURSOHWV VWLFN WRJHWKHU JUDGXDOO\ WKH FUHDP WKLFNHQV DQG WKHQ IRUPV SLHFHV RI EXWWHU flRDWLQJ LQ D OLTXLG FDOOHG buttermilk which is drained away. 7KH VPDOO DPRXQW RI OLTXLG WKDW LV OHIW IRUPV WLQ\ GURSOHWV ZLWKLQ WKH IDW ZKLFK WKH OHFLWKLQ NHHSV GLVWULEXWHG WKURXJKRXW LW Ice cream ,FH FUHDP LV D JRRG H[DPSOH RI FROORLG FKHPLVWU\ ,W LV HVVHQWLDOO\ D PL[WXUH RI FUHDP PLON VROLGV VXJDU DQG ZDWHU ,I WKHVH ZHUH MXVW PL[HG WRJHWKHU SRXUHG LQWR D FRQWDLQHU DQG IUR]HQ WKH\ ZRXOG IRUP D VROLG KDUG OXPS FRQWDLQLQJ ODUJH LFH FU\VWDOV DQG VROLG FUHDP DQG QRW UHVHPEOH LQ DQ\ ZD\ WKH IDPLOLDU VPRRWK FUHDP\ GHVVHUW WKDW LV NQRZQ DV LFH FUHDP ,Q RUGHU WR WXUQ WKHP LQWR WKLV IDPLOLDU IRRG SURGXFW IRRG VFLHQFH LV LQYROYHG DV described below. ,FH FUHDP PL[WXUH LV D VHPL VROLG IUR]HQ emulsion and foam FRQWDLQLQJ IRXU EDVLF LQJUHGLHQWV SOXV air cells : 1. Water as ice crystals (from water added and water naturally in the cream). 2. Fat PLON IDW >EXWWHUIDW FUHDP@ RU QRQ PLON IDW VXFK DV YHJHWDEOH RLO 3. Sugar LQ WKH IRUP RI V\UXSV FU\VWDO VXJDU RU KRQH\ 4. Other solids H J QRQ IDW PLON VROLGV VXFK DV PLON SURWHLQV DQG flDYRXULQJV VXFK DV IUXLW >RIWHQ DGGHG DV IUXLW V\UXSV RU VDXFHV@ KRQH\FRPE FKRFRODWH WRʏHH HWF ,Q PDQ\ KRPHPDGH DQG SUHPLXP EUDQG FRPPHUFLDOO\ PDGH LFH FUHDPV WKH EDVLF LQJUHGLHQWV DUH SUHVHQW LQ WKH IROORZLQJ SURSRUWLRQV ~ = approximately) :DWHU ~60% Fat: ~10–20% 6XJDU ~15% 1RQ IDW PLON VROLGV ~10% Water – approximately 80% of the water in ice cream (much of which comes from the FUHDP IRUPV WKH LFH FU\VWDOV WKDW JLYH WKH SURGXFW LWV QDPH :KHQ ZDWHU IUHH]HV LWV PROHFXOHV ORVH HQHUJ\ DQG GR QRW PRYH DURXQG VR PXFK DV WKH\ GR ZKHQ LW LV D OLTXLG 7KLV FDXVHV VWURQJHU DQG PRUH VWDEOH K\GURJHQ ERQGV WR IRUP EHWZHHQ DGMDFHQW ZDWHU PROHFXOHV UHVXOWLQJ LQ WKH IRUPDWLRQ RI D FU\VWDO ODWWLFH VKDSH 7KLV FDXVHV WKH ZDWHU WR expand as it freezes. Buttermilk and butter formed during the churning of cream The properties of foods and how they are changed
Made with FlippingBook
RkJQdWJsaXNoZXIy Nzc1OTg=