New York Codes, Rules and Regulations › Title 1 - DEPARTMENT OF AGRICULTURE AND MARKETS › Chapter I - Milk Control › Subchapter A - Dairy Products (Article 4, Agriculture and Markets Law) › Part 2 - Requirements For The Production, Processing, Manufacturing And Distribution Of Milk And Milk Products › Sanitation Requirements Applicable to the Processing and Manufacturing of Milk, Lowfat Milk, Skim Milk, Milk Products, Goat Milk, Goat Milk Products, Sheep Milk Products, Melloream and Frozen Desserts › Section 2.46 - High-temperature-short-time, (htst), continuous-flow pasteurization-item 16p(b)

Current through Register Vol. 46, No. 28, July 10, 2024
(a) Indicating
					 thermometers and recorder/controller instruments. All indicating thermometers
					 and recorder/controller instruments and devices used in connection with the
					 high-temperature-short-time, continuous-flow pasteurization of milk or milk
					 products shall comply with the applicable specifications set forth in Appendix
					 3 of this Title.
(b) Automatic milk
					 controller. Each high-temperature-short-time, continuous-flow pasteurization
					 system shall be equipped with an automatic milk flow control of the diversion
					 type, which complies with the following definition, specifications and
					 performance requirements:
(1) Automatic
					 milk-flow controls. The term automatic milk-flow controls shall mean those
					 safety devices which control the flow of milk in relation to the temperature of
					 the milk, or heating medium and/or pressure, vacuum or other auxiliary
					 equipment. Milk-flow controls shall not be considered as part of the
					 temperature control equipment. Milk-flow controls shall be of the
					 flow-diversion type which automatically cause the diversion of the milk in
					 response to a sublegal pasteurization temperature. At sublegal temperatures,
					 flow-diversion devices return the milk to the raw milk side of the heating
					 system continuously until legal pasteurization temperatures are obtained; at
					 which time, the device restores forward flow through the pasteurizer.
(2) Flow-diversion devices. All
					 flow-diversion devices used in continuous pasteurizers shall comply with the
					 following or equally satisfactory specifications:
(i) Forward flow of subtemperature milk, due
					 to the omission or looseness of the connecting clip, shall be prevented by
					 making the valve and its actuating mechanism integral; or, where there is a
					 connecting device, by making it impossible to assemble the valve and its
					 actuating mechanism, except in such manner that it will function properly; or,
					 where there is a connecting device which may be omitted or shaken loose by
					 providing for pushing, instead of pulling, the valve to the diverted position;
					 or by providing that the pump will shut down when the milk is below the
					 pasteurization temperature and the valve is not in the fully diverted position;
					 or by any other equally satisfactory means.
(ii) When a packing gland is used to prevent
					 leakage around the actuating stem, it shall be impossible to tighten the stem
					 packing nut to such an extent as to prevent the valve from assuming the fully
					 diverted position.
(iii) A leak
					 escape shall be installed on the forward-flow side of the valve seat. However,
					 when back pressure is exerted on the forward-flow side of the valve seat, while
					 the milk-flow is being diverted, the leak escape should lie between two valve
					 seats, or between two portions of the same seat, one upstream and the other
					 downstream from the leak escape. The leak escape shall be designed and
					 installed to discharge all leakage to the outside, or to the constant-level
					 tank through a line separate from the diversion line, provided that, when
					 leakage is discharged to the constant-level tank, a sight glass shall be
					 installed in the leak escape line to provide a visual means of leak
					 detection.
(iv) The closure of the
					 forward-flow seat shall be sufficiently tight so that leakage past it will not
					 exceed the capacity of the leak escape device, as evidenced when the
					 forward-flow line is disconnected; and in order that proper seating may not be
					 disturbed, the length of the connecting rod shall not be adjustable by the
					 user.
(v) The flow-diversion device
					 shall be so designed and installed that failure of the primary motivating power
					 shall automatically divert the flow of milk.
(vi) The flow-diversion device shall be
					 located downstream from the holder. The flow-control sensor shall be located in
					 the milk line not more than 18 inches upstream from the flow-control
					 device.
(vii) In the case of
					 higher-heat-shorter-time (HHST) pasteurizing systems utilizing the temperatures
					 of 191° F (89° C) and above and holding times of one second and less,
					 the flow-diversion device may be located downstream from the regenerator and/or
					 cooler sections; provided that, when the flow-diversion device is located
					 downstream from the regenerator and/or cooler section, the flow-diversion
					 device shall be automatically prevented from assuming the forward-flow position
					 until all product-contact surfaces between the holding tube and flow-diversion
					 device have been held at or above the required pasteurization temperature
					 continuously and simultaneously for at least the required pasteurization time
					 as set forth in section
					 2.44  of
					 this Part.
(viii) The pipeline from
					 the diversion port of the flow-diversion device shall be self-draining, and
					 shall be free of restrictions or valves, unless such restrictions or valves are
					 so designed that stoppage of the diversion line cannot occur.
(ix) When it is used, the pipeline from the
					 leak detector port of the flow-diversion device shall be self-draining, and
					 shall be free of restrictions or valves, unless such restrictions or valves are
					 so designed that stoppage of the leak detector line cannot occur.
(3) Milk-flow controller
					 instrumentation. The following requirements shall be met with respect to the
					 instrumentation of the milk-flow controller:
(i) The thermal limit controller shall be set
					 and sealed so that forward flow of product cannot start unless the temperature
					 at the controller sensor is above the required pasteurization temperature as
					 defined in section
					 2.2(a) 
					 of this Part for the milk or milk product and the process used, nor continue
					 during descending temperatures when the temperature is below the required
					 pasteurization temperature. The seal shall be applied by the commissioner after
					 testing, and shall not be removed without immediately notifying the
					 commissioner. The system shall be so designed that no milk can be bypassed
					 around the controller sensor which shall not be removed from its proper
					 position during the pasteurization process. The cut-in and cut-out milk
					 temperatures, as shown by the indicating thermometer, shall be determined at
					 the beginning of each day's operation and entered upon the recorder chart daily
					 by the plant operator.
(ii) In the
					 case of HHST pasteurization systems, utilizing the temperatures of 191° F
					 (89° C) and above, the holding times of one second or less, with the
					 flow-diversion device located downstream from the regenerator and/or cooler
					 section, additional temperature controllers and timers shall be interwired with
					 the thermal limit controller, and the control system shall be set and sealed so
					 that forward flow of product cannot start until all product-contact surfaces
					 between the holding tube and flow-diversion device have been held at or above
					 the required pasteurization temperature, continuously and simultaneously for at
					 least the required pasteurization time as set forth in section
					 2.44  of
					 this Part. The control system shall also be set and sealed so that forward flow
					 cannot continue when the temperature of the product in the holding tube is
					 below the required pasteurization temperature. The seal shall be applied by the
					 commissioner after test, and shall not be removed without immediately notifying
					 the commissioner. The system shall be so designed that no product can be
					 bypassed around the control sensors, which shall not be removed from their
					 proper position during the pasteurization process. For these HHST systems,
					 daily measurement by the operator of the cut-in and cut-out temperatures is not
					 required.
(iii) Manual switches for
					 the control of pumps, homogenizers or other devices which produce flow through
					 the holder, shall be wired so that the circuit is completed only when the milk
					 is above the required pasteurization temperature as set forth in section
					 2.44  of
					 this Part for the milk or milk product and the process used, or when the
					 diversion device is in the fully diverted position.
(4) Holding tube.
(i) Holders shall be designed to provide for
					 the holding of every particle of milk or milk product for at least the time
					 required in section
					 2.2(a) 
					 of this Part for the milk or milk product and the process used.
(ii) The holder shall be so designed that the
					 simultaneous temperature difference between the hottest and coldest milk in any
					 cross-section of flow at any time during the holding period will not be greater
					 than one degree Fahrenheit (one-half degree Celsius). This requirement may be
					 assumed to have been satisfied without test in tubular holders of seven inches
					 or smaller diameter which are free of any fittings through which the milk may
					 not be thoroughly swept.
(iii) No
					 device shall be permitted for short-circuiting a portion of the holder to
					 compensate for changes in rate of milk flow. Holding tubes shall be installed
					 so that sections of pipe cannot be left out, resulting in a shortened holding
					 time.
(iv) The holding tube shall
					 be arranged to have a continuously upward slope in the direction of flow of not
					 less than 0.25 inch per foot.
(v)
					 Supports for tubes shall be provided to maintain all parts of holding tubes in
					 a fixed position, free from any lateral or vertical movement.
(vi) The holder shall be so designed that no
					 portion between the inlet and the flow-control temperature sensor is
					 heated.
(vii) The holding time for
					 the HHST processes must be determined from the pumping rate rather than by the
					 salt conductivity test, because of the short holding tube. The holding tube
					 length must be such that the fastest flowing particle of any product will not
					 traverse the holding tube in less than the required holding time. Since laminar
					 flow (the fastest flowing particle travels twice as fast as the average flowing
					 particle) can occur in the holding tube during pasteurization of high-viscosity
					 products, holding tube lengths are calculated as twice the length required to
					 hold the average flow for the time standard.
(viii) With the steam injection processes,
					 the holding time is reduced because the product volume increases as the steam
					 condenses to water during heating in the injector. This surplus water is
					 evaporated as the pasteurized product is cooled in the vacuum chamber. For
					 example, with a 120° F (66° C) increase by steam injection, which is
					 probably the maximum temperature rise that will be used, a volume increase of
					 12 percent will occur in the holding tube. The measurement of the average flow
					 rate at the discharge of the pasteurizer does no reflect this volume increase
					 in the holding tube. However, this volume increase, i.e., holding time
					 decrease, must be considered in the calculations.
(ix) With the steam injection process a
					 pressure limit indicator is needed in the holding tube to keep the heated
					 product in the liquid phase. The instrument must have a pressure switch so that
					 the flow-diversion device will move to the divert position if the product
					 pressure falls below a prescribed value. For operating temperatures between
					 191° F (89° C) and 212° F (100° C), the pressure switch must be
					 set at 10 pounds per square inch (psi). For units which have operating
					 temperatures above 212° F (100° C), the pressure switch must be set at
					 a pressure 10 psi above the boiling pressure of the product at its maximum
					 temperature in the holding tube.
(x) With the steam injection process, a
					 differential pressure limit indicator across the injector is needed to ensure
					 adequate isolation of the injection chamber. The instrument must have a
					 differential pressure switch so that the flow-diversion device will move to the
					 divert position if the pressure drop across the injector falls below 10
					 psi.
(5) Indicating and
					 recording thermometers.
(i) An indicating
					 thermometer shall be located as near a practicable to the temperature sensor of
					 the recorder/controller, but may be located a short distance upstream from the
					 latter where milk between the two thermometers does not differ significantly in
					 temperature.
(ii) The temperature
					 shown by the recorder/controller shall be checked daily by the plant operator
					 against the temperature shown by the indicating thermometer. Readings shall be
					 recorded on the chart. The recorder/controller shall be adjusted to read no
					 higher than the indicating thermometer.
(iii) The recorder/controller charts shall
					 comply with the applicable provisions of section
					 2.48 
					 of this Part (Item 16p[D]).
(6) Flow-promoting devices.
(i) The pump, or pumps, and other equipment
					 which may produce flow through the holder shall be located upstream from the
					 holder, provided that pumps and other flow-promoting devices may be located
					 downstream from the holder if means are provided to eliminate negative pressure
					 between the holder and the inlet to such equipment. When vacuum equipment is
					 located downstream from the holder, an effective vacuum breaker, plus an
					 automatic means of preventing a negative pressure in the line between the
					 flow-diversion device and the vacuum chamber, shall be acceptable.
(ii) The speed of pumps or other
					 flow-promoting devices governing the rate of flow through the holder shall be
					 so controlled as to insure the holding of every particle of milk for at least
					 the time required, as set forth in section
					 2.44  of
					 this Part, for the milk or milk product and the process used. In all cases, the
					 motor shall be connected to the metering pump by means of a common drive shaft,
					 or by means of gears, pulleys or a variable-speed drive, with the gear box, the
					 pulley box, or the setting of the variable speed protected in such a manner
					 that the holding time cannot be shortened without detection by the
					 commissioner. This shall be accomplished by the application of a suitable
					 seal(s) after tests by the commissioner, and such seal shall not be broken
					 without immediately notifying the commissioner. The provision shall apply to
					 all homogenizers used as timing pumps. Variable speed drives used in connection
					 with the metering pump shall be so constructed that wearing or stretching of
					 the belt results in a slowdown, rather than a speedup, of the pump. The
					 metering or timing pump shall be of the positive displacement type.
(iii) The holding time shall be taken to mean
					 the flow time of the fastest particle of milk, at or above the required
					 pasteurization temperature, as set forth in section
					 2.44  of
					 this Part, for the milk or milk product and the process used, throughout the
					 holder section; i.e., that portion of the system that is outside of the
					 influence of the heating medium, and slopes continuously upward in the
					 downstream direction, and is located upstream from the flow-diversion device.
					 Tests for holding time shall be made when all equipment and devices are
					 operated and adjusted to provide for maximum flow. When a homogenizer is
					 located upstream from the holder, the holding time shall be determined with the
					 homogenizer in operation with no pressure on the homogenizer valves. Where
					 bypass lines are provided, either upstream or downstream from the metering
					 pump, the holding time shall be tested with both the regular and bypass line
					 open, unless the bypass valve is so designed that both lines cannot be open at
					 the same time. The holding time shall be tested during both forward and
					 diverted flow. If necessary to lengthen the holding time during diverted flow,
					 an identifiable restriction may be placed in the vertical portion of the
					 diversion pipeline. When vacuum equipment is located downstream from the
					 holder, the holding time shall be tested with the metering pump operating at
					 maximum flow, and the vacuum equipment adjusted to provide for the maximum
					 vacuum. The holding time shall be tested in both forward and diverted flow by
					 the regulatory agency initially, quarterly thereafter, after any alteration or
					 replacement that may effect the holding time, and whenever the seal of the
					 speed setting has been broken.
(7) Heating by direct addition of steam.
					 Steam injection is an inherently unstable process; accordingly, when steam is
					 injected into a fluid, condensation of the steam may not be completed inside
					 the injector unless the proper design criteria are used. Lack of complete
					 condensation inside the injector would cause temperature variations in the
					 holding tube that could lead to some product particles being processed below
					 pasteurization temperature. When culinary steam is introduced directly into
					 milk or milk products, as the means of terminal heating to achieve
					 pasteurization temperature, the steam injector shall be designed, installed and
					 operated to comply with the following or equally satisfactory specifications:
(i) The product and steam flows must be
					 isolated from pressure fluctuations inside the injection chamber. One method of
					 isolation is to insert supplementary orifices on the product inlet and the
					 heated product outlet of each injector. The two supplementary orifices must be
					 sized for at least a 10 psi product pressure drop across the injector during a
					 simulation of normal operations. Excessive vibrations, pressure fluctuations or
					 erratic noise levels indicate an unstable steam injection system and a need to
					 check the isolation of the injection chamber.
(ii) The product pressure in the holding tube
					 must be of sufficient magnitude to condense the steam and keep the heated
					 product in the liquid phase. If this pressure is too low, the resultant
					 vaporization in the holding tube will substantially reduce residence times. A
					 minimum product pressure in the holding tube of 10 psi for operating
					 temperatures from 191° F (89° C) through 212° F (100° C) is
					 satisfactory. For units which have operating temperatures above 212° F
					 (100° C), the pressure of the product in the holding tube must be at least
					 10 psi above the boiling pressure of the product at its maximum temperature in
					 the holding tube.
(iii) The process
					 should be as free as possible of noncondensable gases that may evolve from the
					 product or be carried in the steam supply. Any two-phase flow caused by the
					 noncondensable gases would displace the product in the holding tube, resulting
					 in reduced residence times. In addition, these gases in the steam supply may
					 also markedly alter the condensation mechanism at the point of injection.
					 Accordingly, the steam boiler shall be supplied with a deaerator. The deaerator
					 will aid in keeping the product in the holding tube as free as possible of
					 noncondensable gases.
(8) Prevention of product adulteration with
					 added water.
(i) When culinary steam is
					 introduced directly into the milk or milk product downstream from the
					 flow-diversion device, means shall be provided to preclude the addition of
					 steam to the product, unless the flow-diversion device is in the forward-flow
					 position. This provision may be satisfied by the use of an automatic steam
					 control valve with temperature sensor located downstream from the steam inlet,
					 or by the use of an automatic solenoid valve installed in the steam line and so
					 wired through the flow-diversion device controls that steam cannot flow unless
					 the flow-diversion device is in the forward-flow position.
(ii) When culinary steam is introduced
					 directly into the milk or milk product, automatic means shall be provided to
					 maintain a proper temperature differential between incoming and outgoing milk
					 to preclude dilution with water.
(iii) Where a water feed line is connected to
					 a vacuum condenser and the vacuum condenser is not separated from the vacuum
					 chamber by a physical barrier, means shall be provided to preclude the backup
					 and overflow of water from the vacuum condenser to the vacuum chamber. This
					 provision may be satisfied by the use of a safety shutoff valve, located on the
					 water feed line to the vacuum condenser, automatically actuated by a control
					 which will shut off the inflowing water, if for example, the condensate pump
					 stops and the water level rises above a predetermined point in the vacuum
					 condenser. This valve may be actuated by water, air or electricity, and shall
					 be so designed that failure of the primary motivating power will automatically
					 stop the flow of water into the vacuum condenser.