Chapter 3 of 6 · 1464 words · ~7 min read

PART I

Date_________________________ Receipt Number___________________

CREAM: ICE CREAM: Age______________ Gallons_______________________ Acidity_______ Weight per gallon_____________ Temperature_______ SWELL: STANDARDIZATION: Gallons________ Per cent.____ Per cent_ fat in cream______ Per cent_ fat in milk_______ FREEZING: Standardize_______ pounds of Freezer used_________ cream testing___________ per Pounds ice used _____ cent fat. Pounds salt used_______

[Illustration] TIME: Of starting freezer___________ That mix reaches 30° F________ Required to reach 30° F_______ That freezing is completed____ Total time required to freeze___ Give proportion. x = the pounds______________ Pounds of cream used________ TEMPERATURE: Pounds of milk used_________ Of mix entering freezer_______ Of brine when mix reaches 30° F____ MIX: Of ice cream when removed_____ Pounds_______ Gallons_______ Of brine at this time_________ Weight per gallon___________ Per cent fat it should test________

Was gelatin used?_______ By method 1, 2 or 3?_______ In milk or water?_______

Remarks:

Comments on ice cream after it is hardened:

EXERCISE NUMBER XXIV

FREEZE ICE CREAM FROM RAW, PASTEURIZED, EMULSIFIED AND HOMOGENIZED CREAM

Note effect on swell and quality of ice cream.

In order to have the ice cream in condition to make easy comparison, it should all be made after the same receipt.

40 pounds 20% cream 8 pounds sugar 4 ounces vanilla extract 4 ounces gelatin in 4 pounds water

With sufficient fresh cream to make four batches of ice cream, divide the cream into four equal parts.

I. Freeze one part directly. II. Pasteurize one part and freeze. III. Emulsify one part and freeze. IV. Homogenize one part and freeze.

If desired all may be aged before freezing.

Fill out record blank on opposite page.

EXERCISE XXIV REPORT

=========================+=====+=====+=====+==== Batch Number | 1 | 2 | 3 | 4 -------------------------+-----+-----+-----+----- Pounds of Mix | | | | -------------------------+-----+-----+-----+----- Gallons of Mix | | | | -------------------------+-----+-----+-----+----- Temperature of Mix | | | | -------------------------+-----+-----+-----+----- Time of Starting Freezer | | | | -------------------------+-----+-----+-----+----- Time of Stopping Freezer | | | | -------------------------+-----+-----+-----+----- Temperature of Ice Cream | | | | -------------------------+-----+-----+-----+----- Gallons of Ice Cream | | | | -------------------------+-----+-----+-----+----- Gallons of Swell | | | | -------------------------+-----+-----+-----+----- Per Cent of Swell | | | | -------------------------+-----+-----+-----+-----

Comments:

EXERCISE NUMBER XXV

THE EFFECT OF AGING CREAM ON THE VISCOSITY AND SWELL

Twenty per cent. cream of nearly uniform quality will be furnished you, of the following ages from the separator: three to four hours, one day, two days, three days, and five days. Freeze a batch of each as assigned, using the following formula, and pay special attention to the swell obtained.

Also test each cream for viscosity by dropping from a pipette on an inclined glass, taking care to have the glass and pipette of even temperature for each trial.

Fill out blank report on opposite page.

_Receipt_:

40 pounds 20% cream 8 pounds sugar 4 ounces vanilla extract 4 ounces gelatin in 4 pounds water.

EXERCISE XXV REPORT

Date_________________________ Receipt Number___________________

Was gelatin used?_______ By method 1, 2 or 3?_______ In milk or water?_______

Remarks:

Comments on ice cream after it is hardened:

EXERCISE NUMBER XXVI

THE EFFECT OF THE TEMPERATURE OF THE MIX AS IT ENTERS THE FREEZER ON THE SWELL

Make enough mix for four 10 gallon batches of ice cream, using the following formula:

40 pounds of 20% cream 8 pounds of sugar 4 ounces of vanilla extract 4 ounces of gelatin in 4 pounds water.

Freeze the first batch as a preliminary one. Have the second at a temperature of 40 degrees F., when it enters the freezer, the third at 50 degrees F., and the fourth at 60 degrees F. Warm to these temperatures before placing mix in freezer. Note swell obtained. Explain.

Fill out record blank on opposite page.

EXERCISE XXVI REPORT

Comments:

EXERCISE NUMBER XXVII

EFFECT OF THE TIME OF FREEZING ON THE SWELL AND QUALITY OF ICE CREAM

Make enough mix for four 10 gallon batches of ice cream, using the following formula:

40 pounds of 20% cream 8 pounds of sugar 4 ounces of vanilla extract 4 ounces of gelatin in 4 pounds water

Freeze the first batch as a preliminary one. Regulate either the temperature or quantity of brine so that the second batch will freeze in four minutes, the third in fifteen minutes, and the fourth in thirty minutes.

Note particularly the effect on the swell and quality.

Fill out the record blank on opposite page.

EXERCISE XXVII REPORT

=========================+=====+=====+=====+===== Batch Number | 1 | 2 | 3 | 4 -------------------------+-----+-----+-----+----- Pounds of Mix | | | | -------------------------+-----+-----+-----+----- Gallons of Mix | | | | -------------------------+-----+-----+-----+----- Temperature of Mix | | | | -------------------------+-----+-----+-----+----- Time of Starting Freezer | | | | -------------------------+-----+-----+-----+----- Time of Stopping Freezer | | | | -------------------------+-----+-----+-----+----- Temperature of Ice Cream | | | | -------------------------+-----+-----+-----+----- Gallons of Ice Cream | | | | -------------------------+-----+-----+-----+----- Gallons of Swell | | | | -------------------------+-----+-----+-----+----- Per Cent of Swell | | | | -------------------------+-----+-----+-----+-----

Comments:

EXERCISE NUMBER XXVIII

BACTERIAL COUNTS OF ICE CREAM

This exercise is to be performed once during the course by each student as assigned.

Sterile glassware and media will be furnished you. Weigh or measure the samples for dilution as instructed.

Take samples as indicated below in sterile bottles and plate on plain lactose agar. Incubate at 37 degrees C., for 48 hours.

Sample of cream. Dilutions ¹/₁₀,₀₀₀ and ¹/₁₀₀,₀₀₀. Sample of gelatin. Dilutions ¹/₁₀ and ¹/₁₀₀. Sample of vanilla. Dilutions ¹/₁₀. Sample of sugar. Dilutions ¹/₁₀. Sample of mix. Dilutions ¹/₁₀,₀₀₀ and ¹/₁₀₀,₀₀₀. Sample of ice cream from freezer. Dilutions ¹/₁₀,₀₀₀ and ¹/₁₀₀,₀₀₀. Sample of ice cream after it has remained in the hardening room one week. Make dilutions of ¹/₁₀,₀₀₀ and ¹/₁₀₀,₀₀₀.

Report results on the blank page opposite.

EXERCISE XXVIII REPORT

EXERCISE NUMBER XXIX

TESTING SAMPLES OF GELATIN

Weigh 5 gram samples of gelatin into 100 cc. of cold water in beakers or jelly glasses. Allow it to soak over night. Then heat slowly, with stirring, to 80 degrees C.

Subject to the following tests and make report on opposite blank page.

1. Note the odor.

2. Determine the time required for 50 cc. to run from a pipette.

3. Determine the time required for the sample to gelatinize.

4. Turn the jelly out on to a plate and determine the relative resistance of the different samples to pressure by the finger.

Two or more students should be assigned to this exercise at a time, each having a different sample of gelatin. They should perform the tests together.

EXERCISE XXIX REPORT

EXERCISE NUMBER XXX

TRIP TO COMMERCIAL PLANTS

Visit at least one large commercial plant some time during the term and report on the following points.

Points to be observed in an ice cream plant.

1. Method of securing the raw product. 2. Is cream pasteurized? 3. If possible, amounts and materials used in mix. 4. Is condensed milk used? 5. What stabilizer is used? 6. Time of aging cream or mix. 7. Kinds of freezer and ice machine. 8. Temperature of brine to freeze. 9. Composition of ice cream. 10. Sketch of arrangement of plant. 11. Power used for delivering. 12. Method of checking up drivers. 13. Any other points of interest.

EXERCISE XXX REPORT

EXERCISE NUMBER XXXI

STUDENTS’ RECEIPTS

Each student should hand in one receipt for ice cream. This receipt should be one which has been previously tried, preferably at home.

During the term these receipts will be made.

Note the quality of the ice cream.

Is the ice cream a good commercial ice cream?

Could it be made on a commercial basis profitably?

EXERCISE XXXI REPORT

EXERCISE XXI REPORT