User:Sverazo - ChemPRIME

User:Sverazo

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Sofia Erazo

Ph.D. candidate, Food Science

Project: Decolorization of whey and recovery of milk phospholipids


Fats and Lip in Fds

Ionic Equilibria in Aqueous Solutions in Foods

Ionization of Water in Foods

Solubility of calcium salts in foods

Low solubility salts in dairy products - Calcium phosphate and lactate

Calcium tartrate and treatment of wine waste-waters

Ksp and calcium fortification

More Salts of Weak Acids and Exceptions

Undesirable effects

Page in progress

Cleaning operations

Another area in food processing where the solubility behavior of salts derived from weak acids has important implications is in cleaning operations. Even though food processing plants are careful in monitoring water hardness, deposits of calcium and magnesium salts may still form on the surface of processing equipment and pipes. This is specially true for plants that handle products or ingredients inherently rich in calcium, for example dairy plants. The deposits of low solubility salts present in water (i.e.,calcium, magnesium, iron, and manganese salts) can provide a foundation for the attachment of bacteria, macromolecules, and the formation of biofilms. Using acidic cleaning and rinsing solutions dissolves the salts decreasing the potential for deposits and biofilm formation. Special care, however, must be taken when using chlorine based cleansing and sanitizing solutions.

The salts involved in water hardness are also deleterious in processing and cleaning operations because high concentrations of calcium and magnesium contained in hard water can bind to cleansers and sanitizers decreasing their effectiveness.[1] Calcium and magnesium salts also decrease the ability of water to remove bacteria from food and processing surfaces. Hinton and Holser reported that hard water used in rinsing skin of processed broiler chickens removed significantly less bacteria than soft water.[2]

Water softening strategies take advantage of the solubility equilibrium of salts with the addition of sequestering agents. As used in food formulations, addition of anions capable of binding calcium and magnesium, for example, citrates, favors the dissociation of the salt increasing its solubility. Soaps and detergents also include this type of agents where they are called "detergent builders".

This is in addition to the changes in pH and solubility of calcium already discussed and affected by the absorption of volatile organic acids form the smoke.

A more recent study evaluated the effect of starter culture, pH, lactic acid concentration, calcium (total and soluble), and salt on the development of calcium lactate crystals in early stages of the manufacture process and later during curing. During the cheese making process and early curing stages (7 days), pH, lactic acid concentration, nonprotein nitrogen, and calcium (total and soluble) in cheese did not correlate with formation of calcium lactate crystals or expulsion of liquid in Cheddar cheese. During curing however, pH, lactic acid concentration, and soluble calcium appeared to be associated to crystal formation and seemed to be related with the use of specific starter cultures. The cheese that did not show calcium lactate crystals during the course of the study was made with starter culture characterized by the least pronounced change in pH during the first month of curing.

Smoking

  1. Dehydration
  2. Solid concentration: lactate and salt gradients
  3. Low pH (gradient): Absorption of volatile organic acids
  4. Calcium shifts/solubility
  5. Gradients of solids disapeared with time

Protein and calcium interactions

Kovach, S.M. 2007. Improve your cleaning process. How water hardness affects cleaning. Mater. Manag Health Care. 16:9:52-3.

Treatment of waste from the wine industry is limited by

  1. Insufficient policies and regulations variable across countries and regions

An alternative for reduction of waste sources and is the adoption of biodynamic and organic practices for wine production.

CaC2O4


Solubility of lisozyme


Zeoponic substrates

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Calcium phosphate


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Wiki Code Table

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Column 1 Column 2
Row A Row A
Row B Row B Row B
Substance Ksp Substance Ksp
Aluminum Compounds Barium Compounds
AlAsO4 1.6 × 10-16 Ba3(AsO4)2 8.0 × 10-15
Al(OH)3 amorphous 1.3 × 10-33 BaCO3 5.1 × 10-9
AlPO4 6.3 × 10-19 BaC2O4 1.6 × 10-7
Bismuth Compounds BaCrO4 1.2 × 10-10
BiAsO4 4.4 ×10-10 BaF2 1.0 × 10-6
BiOCl2 7.0 × 10-9 Ba(OH)2 5 × 10-3
BiO(OH) 4 × 10-10 Ba3(PO4)2 3.4 × 10-23
Bi(OH)3 4 ×10-31 BaSeO4 3.5 × 10-8
Bil3 8.1 ×10-19 BaSO4 1.1 × 10-10
BiPO4 1.3 ×10-23 BaSO3 8 × 10-7
Cadmium Compounds BaS2O3 1.6 × 10-5
Cd3(AsO4)2 2.2 ×10-33 Calcium Compounds
CdCO3 5.2 ×10-12 Ca3(AsO4)2 6.8 ×10-19
Cd(CN)2 1.0 ×10-8 CaCO3 2.8 ×10-9
Cd2[Fe(CN)6] 3.2 ×10-17 CaCrO4 7.1 ×10-4
Cd(OH)2 fresh 2.5 ×10-14 CaC2O4 • H2O3 4 × 10-9
Chromium Compounds CaF2 5.3 ×10-9
CrAsO4 7.7 × 10-21 Ca(OH)2 5.5 ×10-6
Cr(OH)2 2 × 10-16 CaHPO4 1 × 10-7
Cr(OH)3 6.3 × 10-31 Ca3(PO4)2 2.0 × 10-29
CrPO4 • 4H2O green 2.4 × 10-23 CaSeO4 8.1 × 10-4
CrPO4 • 4H2O violet 1.0 × 10-17 CaSO4 9.1 × 10-6
Cobalt Compounds CaSO3 6.8 × 10-8
Co3(AsO4)2 7.6 × 10-29 Copper Compounds
CoCO3 1.4 × 10-13 CuBr 5.3 × 10-9
Co(OH)2 fresh 1.6 × 10-15 CuCl 1.2 × 10-6
Co(OH)3 1.6 × 10-44 CuCN 3.2 × 10-20
CoHPO4 2 × 10-7 CuI 1.1 × 10-12
CO3(PO4)2 2 × 10-35 CuOH 1 × 10-14
Gold Compounds CuSCN 4.8 × 10-15
AuCl 2.0 × 10-13 Cu3(AsO4)2 7.6 × 10-36
AuI 1.6 × 10-23 CuCO3 1.4 × 10-10
AuCl3 3.2 × 10-25 Cu2[Fe(CN)6] 1.3 × 10-16
Au(OH)3 5.5 × 10-46 Cu(OH)2 2.2 × 10-20
AuI3 1 × 10-46 Cu3(PO4)2 1.3 × 10-37
Iron Compounds Lead Compounds
FeCO3 3.2 × 10-11 Pb3(AsO4)2 4.0 × 10-36
Fe(OH)2 8.0 × 10-16 PbBr2 4.0 × 10-5
FeC2O4 • 2H2O3 3.2 × 10-7 PbCO3 7.4 × 10-14
FeAsO4 5.7 × 10-21 PbCl2 1.6 × 10-5
Fe4[Fe(CN)6]3 3.3 × 10-41 PbCrO4 2.8 × 10-13
Fe(OH)3 4 × 10-38 PbF2 2.7 × 10-8
FePO4 1.3 × 10-22 Pb(OH)2 1.2 × 10-15
Magnesium Compounds PbI2 7.1 × 10-9
Mg3(AsO4)2 2.1 × 10-20 PbC2O4 4.8 × 10-10
MgCO3 3.5 × 10-8 PbHPO4 1.3 × 10-10
MgCO3 • 3H2O3 2.1 × 10-5 Pb3(PO4)2 8.0 × 10-43
MgC2O4 • 2H2O3 1 × 10-8 PbSeO4 1.4 × 10-7
MgF2 6.5 × 10-9 PbSO4 1.6 × 10-8
Mg(OH)2 1.8 × 10-11 Pb(SCN)2 2.0 × 10-5
Mg3(PO4)2 10-23 to 10-27 Manganese Compounds
MgSeO3 1.3 × 10-5 Mn3(AsO4)2 1.9 × 10-29
MgSO3 3.2 × 10-3 MnCO3 1.8 × 10-11
MgNH4PO4 2.5 × 10-13 Mn2[Fe(CN)6] 8.0 × 10-13
Mercury Compounds Mn(OH)2 1.9 × 10-13
Hg2Br2 5.6 × 10-23 MnC2O4 • 2H2O3 1.1 × 10-15
Hg2CO3 8.9 × 10-17 Nickel Compounds
Hg2(CN)2 5 × 10-40 Ni3(AsO4)2 3.1 × 10-26
Hg2Cl2 1.3 × 10-18 NiCO3 6.6 × 10-9
Hg2CrO4 2.0 × 10-9 2 Ni(CN)2 → Ni2+ + Ni(CN)42 1.7 × 10-9
Hg2(OH)2 2.0 × 10-24 Ni2[Fe(CN)6] 1.3 × 10-15
Hg2l2 4.5 × 10-29 Ni(OH)2 fresh 2.0 × 10-15
Hg2SO4 7.4 × 10-7 NiC2O4 4 × 10-10
Hg2SO3 1.0 × 10-27 Ni3(PO4)2 5 × 10-31
Hg(OH)2 3.0 × 10-26 Silver Compounds
Strontium Compounds Ag3AsO4 1.0 × 10-22
Sr3(AsO4)2 8.1 × 10-19 AgBr 5.0 × 10-13
SrCO3 1.1 × 10-10 Ag2CO3 8.1 × 10-12
SrCrO4 2.2 × 10-5 AgCl 1.8 × 10-10
SrC2O4 • H2O3 1.6 × 10-7 Ag2CrO4 1.1 × 10-12
Sr3(PO4)2 4.0 × 10-28 AgCN 1.2 × 10-16
SrSO3 4 × 10-8 Ag2Cr2O7 2.0 × 10-7
SrSO4 3.2 × 10-7 Ag4[Fe(CN)6] 1.6 × 10-41
Tin Compounds AgOH 2.0 × 10-8
Sn(OH)2 1.4 × 10-28 AgI 8.3 × 10-17
Sn(OH)4 1 × 10-56 Ag3PO4 1.4 × 10-16
Zinc Compounds Ag2SO4 1.4 × 10-5
Zn3(AsO4)2 1.3 × 10-28 Ag2SO3 1.5 × 10-14
ZnCO3 1.4 × 10-11 AgSCN 1.0 × 10-12
Zn2[Fe(CN)6] 4.0 × 10-16
Zn(OH)2 1.2 × 10-17
ZnC2O4 2.7 × 10-8
Zn3(PO4)2 9.0 × 10-33



pH and pOH in Food Color

Weak acids in foods - pH and beyond

The pH of Solutions of Weak Bases in Foods

Polyprotic acids and bases in Foods

Conjugate Acid-Base Pairs and pH in Foods - From cleaning and disinfection to microbial nutrition and protein modification

Cleaning and disinfection processes

Tables to review

Bf slns in foods

Buffer solutions and the stability of food additives

Buffer solutions and the production of food ingredients

The effect of polyols on the pH of buffer solutions in foods

Indicators in foods

Acid Value (AV) and the quality of fats and oils


Image:Titolazione.gif


Colorless phenolphthalein (3,3-bis(4-hydroxyphenyl)-2-benzofuran-1-one) at low-pH
A typical indicator for acid-base titrations is phenolphthalein, HC20H13O4. Phenolphthalein, whose structure is shown below, is a colorless weak acid (Ka = 3 × 10–10 mol dm–3). Its conjugate base, C20H13O4– has a strong pinkish-red color. In order to simplify, we will write the phenolphthalein molecule as HIn and its pink conjugate base as In–. In aqueous solution, phenolphthalein will present the following equilibrium


HIn + H2O \rightleftharpoons In– + H3O+      (1)


According to Le Chatelier’s principle, the equilibrium shown in equation (1) will be shifted to the left if H3O+ is added. Thus in a strongly acidic solution we expect nearly all the pink In– to be consumed, and only colorless HIn will remain. On the other hand, if the solution is made strongly basic, the equilibrium will shift to the right because OH– ions will react with HIn molecules, converting them to In–. Thus the phenolphthalein solution will become pink.

Clearly there must be some intermediate situation where half the phenolphthalein is in the acid form and half in the colored conjugate-base form. That is, at some pH


      [HIn] = [In–]


This intermediate pH can be calculated by applying the Henderson-Hasselbalch equation to the indicator equilibrium:


\text{pH}=\text{p}K_{a}\text{ + log}\frac{[\text{ In}^{-}]}{[\text{ HIn }]}


Thus at the point where half the indicator is conjugate acid and half conjugate base,


\text{pH}=\text{p}K_{a}\text{ + log 1} = \text{p}K_{a}\,


For phenolphthalein, we have



\text{pH}=\text{p}K_{a}=-\text{log(3 }\times \text{ 10}^{-10}\text{)}=\text{9.5}


so we expect phenolphthalein to change color in the vicinity of pH = 9.5.


Fig. 1 Color change of phenolphthalein with respect to pH

Fig. 2 Phenolphtalein at different pH, notice the distinctive color at pH 8-12

The way in which both the color of phenolphthalein and the fraction present as the conjugate base varies with the pH is shown in detail in Fig. 1. The change of color occurs over quite a limited range of pH―roughly pKa ± 1. In other words the color of phenolphthalein changes perceptibly between about pH 8.3 and 10.5. Observe the actual color change for this indicator in Fig. 2. Other indicators behave in essentially the same way, but for many of them both the acid and the conjugate base are colored. Their pKa’s also differ from phenolphthalein, as shown in the following table. The indicators listed have been selected so that their pKa values are approximately two units apart. Consequently, they offer a series of color changes spanning the whole pH range.

Polyprotic Acids and Bases: Phosphates, amines Conjugate Acid-Base Pairs and pH Buffer Solutions: Acetates, proteins Indicators -Cabbagge, anthocyanins Titration Curves: Yogurt production and fermented vegetables, cocoa production, wine The Solubility Product: Leavening agents The Common-Ion Effect: Calcium The Solubilities of Salts of Weak Acids: Acetates, citrates

|rowspan="2" align="center"| High acid foods

The Base Constants for Some Bases at 25°C

Base Formula and ionization equation Kb
Amide ion NH2– + H2O \rightarrow NH3 + OH– Large
Ammonia NH3 + H2O \rightleftharpoons NH4 + + OH– 1.8 × 10–5
Aniline C6H5NH2 + H2O \rightleftharpoons C6H5NH3+ + OH– 3.9 × 10–10 or 7.4 10–10
Carbonate ion CO32– + H2O \rightleftharpoons HCO3– + OH– 2.1 × 10–4
Dimethylamine (CH3)2NH + H2O \rightleftharpoons (CH3)2NH2+ + OH– 5.8 × 10–4 or 5.4 × 10–4
Ethylenediamine (CH2)2(NH2)2 + H2O \rightleftharpoons (CH2)2(NH2)2H+ + OH–

(CH2)2(NH2)2H+ + H2O \rightleftharpoons (CH2)2(NH2)2H22+ + OH–

K1 = 7.8 × 10–5 or 8.3 × 10–5

K2 = 2.1 × 10–8 or 7.2× 10–8

Hydrazine N2H4 + H2O \rightleftharpoons N2H5+ + OH–

N2H5+ + H2O \rightleftharpoons N2H6+ + OH–

K1 = 1.2 × 10–6 or 1.3 × 10–6

K2 = 1.3 × 10–15 ??

Hydride ion H– + H2O \rightarrow H2 + OH– Large
Hydroxylamine NH2OH + H2O \rightleftharpoons NH3OH+ + OH– 9.3 × 10–9 or 8.7 × 10–9
Methylamine CH3NH2 + H2O \rightleftharpoons CH3NH3+ + OH– 5.0 × 10–4 or 4.6 × 10–4
Phosphate ion PO43– + H2O \rightleftharpoons HPO42– + OH– 5.9 × 10–3 or 2.1 × 10–2
Pyridine C5H5N + H2O \rightleftharpoons C5H5NH+ + OH– 1.6 × 10–9 or 1.7 × 10–9
Trimethylamine (CH3)3N + H2O \rightleftharpoons (CH3)3NH+ + OH– 6.2 × 10–5 or 6.3 × 10–5



Substance pH [H3O+] [OH-] pOH Strenght
Battery acid   0 1 10-14 14 Strongly acidic
Stomach acid
Lemon juice
  1 10-1 10-13 13
  2 10-2 10-12 12
  3 10-3 10-11 11 Weakly acidic
Soda water   4 10-4 10-10 10
Black coffee   5 10-5 10-9   9 Barely acidic
  6 10-6 10-8   8
Pure water   7 10-7 10-7   7 Neutral
Seawater   8 10-8 10-6   6 Barely basic
Baking soda   9 10-9 10-5   5
Toilette soap 10 10-10 10-4   4 Mildly basic
Laundry water 11 10-11 10-3   3
Household ammonia 12 10-12 10-2   2 Very basic
13 10-13 10-1   1
Drain cleaner 14 10-14 1   0


  Substance Cp (solid)/J K-1 mol-1 Cp (liquid)/J K-1 mol-1
Monoatomic Substances
  Hg 27.28 27.98
  Pb 29.40 30.33
  Na 28.20 31.51
Diatomic Substances
  Br2 53.8 75.7
  I2 54.5 80.7
  HCl 50.5 62.2
  HI 47.5 68.6
Polyatomic Substances
  H2O 37.9 76.0
  NH3 49.0 77.0
  Benzene 129.0 131.0
  n-Heptane 146.0 203.1


  Gas Cv /J K-1 mol-1 Gas Cv /J K-1 mol-1
Monoatomic Gases Triatomic Gases
  Ne 12.47 CO2 28.81
  Ar 12.47 N2O 30.50
  Hg 12.47 (700K) SO2 31.56
  Na 12.47 (1200K)   
Diatomic Gases Alkanes
  N2 20.81 CH4 27.42
  O2 21.06 C2H6 44.32
  Cl2 25.62 C3H8 65.20
   C4H10 89.94
Task: Review conditions for Dutch process!!!Sverazo 20:59, 28 October 2009 (UTC) ( Sofia Erazo )


Task: Please, take a look at this page: http://wiki.chemprime.chemeddl.org/index.php/PH_and_pOH_in_Food_Color , I will appreciate your comments on it Sverazo 15:33, 30 September 2009 (UTC) Looks good to me. Jshorb 18:55, 6 November 2009 (UTC) ( John Moore, Ed Vitz, Sofia Erazo )


Task: Please, take a look at this page: http://wiki.chemprime.chemeddl.org/index.php/Weak_acids_in_foods_-_pH_and_beyond, I will appreciate your comments on itSverazo 18:53, 8 October 2009 (UTC) I like it. Jshorb 18:55, 6 November 2009 (UTC) ( Ed Vitz, John Moore )
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