Summary Chemistry

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Summary - Chemistry

  • 1 Chemistry behind colour changes

  • Can you fill in this table further?
    Zie afbeelding
  • What is the colour of the pigments with the spectra above? an what pigments might these spectra represent?
    First one is yellow/ orange. carotenoid
    Second one is green. chlorophyll
  • 1.1 Caramelization

  • What is the difference in starting compounds of caramelization and the maillard reaction?
    caramelsiation: reducing sugar
    maillard reaction: amino compound
  • When can you make caramel of sugar or sugar syrup?
    You need:
    • persons of acid or alkaline catalysts 
    • low water activity
    • high temperature
  • What are the different reactions happening in caramelization?
    • Enolization
    • Dehydration
    • oxidation
    • Fission
    • Aldol concdensation
  • Is caramelization enzymatic?
    NO
    no enzymes are used and therefore it is not enzymatic browning
  • Why are there differences in caramelization temrpature?
    these sugars consist out of pyranose and furanose ring sugars. Pyranose has one C more and therefore more stable. You need less energy to open the furnaces ring. 
    Also disacharides need more energy to open and therefore a higher temperature. 
  • Hoe does the enolization step in caramel go?
    Dit is een acid catalysed reaction with mono schrods. 
    De dubble band verplaats van de O naar de 2e C. 
    Dit zorgt voor molecular diversity
  • What happens during the dehydration step?
    A H is extracted from the molecule. and you get different round components.
  • What is formed during the dehydration step?
    Aroma compounds
  • What is a aldose and what is a ketose?
    Zie afbeelding
  • Which monosaccharides yield more products in dehydration, aldoses or ketoses?
    Ketoses since the reaction can go 2 ways in the elongation reaction. Therefore you get a bigger variaty of products in the dehydration reaction.
  • What happens in the oxidation reaction of caramelization?
    The enodial formed with the elongation reaction is very reactive. 
    In an oxidation reaction the H of the two upper C goes of and a double C bond is formed. 
  • What is the similarity and difference of the oxidation reaction to the dehydration reaction?

    The similarity to the dehydration is is that highly reactive dicarbonlys are formed. 
    The difference to the dehydration reaction is that no water is dehydrated. 
  • What is the most reactive compound of the caramel reaction?
    Dicarbonyl! 
    They are also very reactive if they are formed by te mallard and enzymatic reactions
  • What is the fission reaction in caramel?
    The dicarbonlyl is split into two compounds. There is a big diversity of molecules that you can make out of this.
  • What is the aldo condensation reaction of caramel?
    Two product of the fission reaction form a small molecule again. Because there are so many compounds that can formed one you get many different products!
  • What it the typical carmal aroma compound?
    The last compound
  • When do you get more aroma compound and when more colour compounds in the caramelization reaction?
    neutral pH aroma compounds
    Exteam pH high or low color compounds
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Welke delen van het molecuul zijn verantwoordelijk voor het cooling effect (gevormd door mailaird reaction)?
Het blauwe deel is minder belangrijk. 
Het groene deel heeft normaal gesproken een negatief effect op de cooling sensation. Behalve in dit molecuul
De rode O is essentieel

Bij het zwarte deel is het belangrijk dat een vijfring is. niet een zesring
Zit capsaicin liever in water of olie?
Olie lange c keten dus apolair
How can you measure the spicynes of pepper without a pennel test?
Kijken hoe groot de responce is van een bepaalde coenntratie van een peper op de TRPV1 en hierdoor kan je voorspellen hoe pittig hij is en hoef je geen pannel test te doen
How can the aroma and tast compounds be formed in saffron?
By the cyclic compounds that are split of by the carotenase. It will give a compound with a sugar unit attached this is the tast compound. When this tast compound is in contact with an encime or heat treatment a aroma compound will be formed. This one is apolair and disolves wel in oil. This happens with cooking
What is similar in all the browning reactiosn in enzymes?
Tyrosinate and oxygen is always used. And different phenolic substrates give browning.
What is the main difference between Pholy Phenol oxidase met laccase en peroxidase?
Laccase and POD are less strict with there substrate and do not nesseserly need phyrosin and polyphenols.
What happens in the strecker reaction?
reachtion with amino acid. From this lot of different moleculs are formed an you can get a lot of different aroma compounds
When can you make caramel of sugar or sugar syrup?
You need:
  • persons of acid or alkaline catalysts 
  • low water activity
  • high temperature
Hoe werkt knettersuiker?
Je genereert CO2 door een zuur en base te laten reageren et elkaar
Welke receptor is verantwoordelijk voor het tingling effect?
TRPA1