IE85451B1 - A method for manufacturing a snack food product - Google Patents

Abstract

ABSTARCT this invention relates to the manufacture of potato crisps. there are several difficulties involved in manufacturing potato crisps on a large scale. One of the problems is that there is a large variation in the raw potatoes used in the process. Several manufacturing steps are involved and these are not easily optimised because ofthc many variables involved.

Description

A method for manutuettiring a snack food product." Introduction this invention relates to the manufacture of potato crisps. there are several difficulties involved in manufacturing potato crisps on a large scale. One of the problems is that there is a large variation in the raw potatoes used in the process. Several manufacturing steps are involved and these are not easily optimised because ofthc many variables involved.

Paclxaging of such products also presents serious difficulties. especially where there is a need to produce a wide range of different products with different packaging requirements. This invention is directed towards providing a manufacturing method which will address at least some ofthese issues.

Statements of Invention According to the invention there is provided a method for manufacturing potato crisps comprising the steps of :- selecting input potatoes with a solids content of from 20% to 25%; loading selected potatoes into a hopper; removing heavy waste from potatoes; washing the potatoes: removing light waste from the washed potatoes; delivering the washed potatoes into one of a plurality of peeling units having cutting means; selecting the residence time in the peeling unit based on the cutting cflicicncy ofthc cutting means; passing the peeled potatoes over a screen: delivering the potatoes to a slicer; slicing the potatoes in the slicer: rinsing the potato slices with water at a temperature otlcss than 25%‘; shaking the washed potato slices to remove excess water: drying the potato slices; leading the potato slices through a bath of heated vegetable oil. the bath having three stages; in a first stage the slices having a residence time of [tom 25 to 35 seconds and the oil being at a temperature of from 172°C to l7‘)"C; in a second stage the slices having a residence time of from 50 to 70 seconds and the oil being at a temperature of from l72"C to l76"L‘; in a third stage the slices having a residence time of from S0 to 70 seconds and the oil being at a temperature of from l60°C to l64"C; testing the quality of the cooked potato slices: in-line rejecting slices which are outside a defined specification; and packaging the cooked potato slices.

In a preferred embodiment in the first stage the slices have a residence time of about 30 seconds and the oil is at a temperature offrom 172 to l74“C. ll 0 in a preferred embodiment in the second stage the slices have a residence time of about 60 seconds and the oil is at a temperature of from 172 to 1 74"C‘.

In a preferred embodiment in the third stage the slices have a residence time of about 60 seconds and the oil is at a temperature of from I60 to l62"C.

Preferably the testing comprises in-line monitoring of the fat and/or moisture content ofthe cooked potato slices.

In one case the testing comprises in-line checking for discoloration on the cooked potato slices.

In a preferred embodiment the method comprises leading the cooked potato slices along a conveyor having a gate. and activating the gate in response to a negative test result to direct the rejected cooked potato slices to a reject bin. Preferably the gate is perforated and pieces of cooked potato slices below a preset size pass through the perforations to a reject bin as the cooked potato slices are led along the conveyor.

The method may comprise directing the cooked potato slices which have passed over the gate to one ofa plurality of proportioners and weighers for packing or to a holding area. In this case the method comprises leading the cooked potato slices delivered to the holding area to a proportioner and weigher. on demand.

In one embodiment the method comprises the step, after shaking. of blanching the potato slices. the heavy waste may be removed in a cyclone destoner.

The light waste may be removed in a floatation tank. to CD In one embodiment the method comprises directing oversize potatoes not passing through the screen to a potato halver in which the oversize potatoes are cut in half and. directing the halved potatoes into the stream of potatoes which have passed through the screen.

The invention also provides a method for packaging snack food products comprising the steps of :- manufacturing snack food products: delivering the snack lood products into single primary bags: delivering the tilled printary bags to one of a plurzslity of multihead weighers; packing a plurality ot‘ tilled primary bags from the multihead v-zeigher in a vertical fomi till and seal unit to form a multipack hag containing a plurality ofthe primary packs: collating the multipack bags at one ofa plurality ofeollating stations: loading the collated multipack bags into a case at the collating station: and delivering Cases containing multipack bags from the collating, stations to a single automatic case sealer. lhc method may comprise the step olin-line seal testing of the multipack bags. "the method may also comprise check weighing the multipack bags prior to collating the bags. to an In one embodiment the method comprises automatically reading a code provided on the case, and automatically adjusting the case seal to correspond to the case to be scaled.

The snack Food may be a crisp product. especially‘ a potato crisp product.

The invention further provides a method for automatically packaging single packs ofa snack food product into a box comprising the steps of :- delivering a plurality of single packs along a conveyor to a packing station, the faces of the single packs being arranged substantially horizontal; depositing a first group of single packs into at holder unit: depositing a second group of single packs into the holder unit on top of the lirst group of packs; presenting a box to the holder unit. the box being orientated such that the top opening of the box is arranged substantially vertically; delivering the groups of single packs into the box through the box opening; turning the box through substantially 90°’ so that the top opening of the box is uppermost and the faces of the packs are arranged substantially vertical; and closing the box.

In one embodiment the single packs are delivered along two substantially parallel lanes and groups of packs from each lane are simultaneously deposited from the lanes into the holder unit.

In one embodiment the depositing comprises lifting a group of single packs up [tom the conveyor, translating the group ofpacks to the holder unit. and dropping the group of packs into the holder unit.

The holder unit may comprise a side flap which is orientated with the box opening and the method comprises the step ofopening the side flap for delivering ot’ the single packs into the box.

In one Case the groups of single packs are delivered into the box by a pusher which engages the groups and pushes them from the holder unit into the box.

Also provided are products when manufactured by the method ol‘the invention.

Brie!’ Description ofthe Drawings The invention will be more clearly understood from the following description thcreol‘ given by way of example only with reference to the accompanying dravtings. in which:- Fig. I is a diagram illustrating various steps in the manufacture of potato crisps; Fig. 2 is a perspective view of a testing section of the manufacturing process; Fig. 3 is a plan view ofa crisps Ilow management section olthe process: t\J an Fig. 4 is a block diagram illustrating the packaging of crisps into single bags: Fig. 5 is a plan view ofzt packaging system for single crisp bags: Fig. 6(a) and 6th) are views illustrating steps in the handling of single crisp bags: Fig. 7 is an clevational view illustrating further steps in the handling of single crisp bags: Fig. 8 is a perspective view of a single bag packer used in the system of Figs. 5 to 7: Fig. 9 is a perspective view ofa case of single pack bags: Fig. 10 is a diagram illustrating a multipaek bag packaging system: Fig. I I is an elevational View of one multipack bag packaging station; and Fig. 12 is a perspective view of plurality of multipaeks packaged into a case. l)etailed Description Potato crisps are manufactured by first selecting potatoes with a solids content 01‘ from 20% to 2 %. The potatoes are preferably of the variety Lady Rosetta which generally have a sol ids content ol‘20% to 22% good colour. size. shape and good quality skin. They are generally used directly after harvesting. Late potatoes of the variety Lady Clare are stored in a controlled storage environment. llie variety Saturna may also be stored in the same way for future processing. In the case of l\J 3 stored potatoes the storage temperature is from 7 to 8"C to minimise sugar development. To prepare the stored potatoes for processing they are first tempered to raise the temperature to between I5 and 20°C over a 24 hour period.

The solids content of the input potatoes is checked and potatoes which have a solids content of preferably 21 to 22% are selected for further processing. This range of solids content enables oil absorption and required moisture content in the linished crisps.

The potatoes are also selected based on size. We have found that for optimum processing efliciency there should be at least 75 and at most l 10 single potatoes per It’) Kgs of input potatoes. The potatoes are graded and those in the size range -"ttlmm to 85mm are selected.

Selected potatoes are loaded into a storage hopper. Potatoes to be processed are first passed through a cyclone. any heavy waste such as stones drop to the base of the cyclone and are discharged to waste. The potatoes are then delivered into a washer reel in which the potatoes are turned in a bath of water to wash soil from the surface of the potatoes. The washed potatoes are then delivered into a floatation tank in which any light waste such as straw floats to the surface and is removed for discharge to waste.

The washed potatoes are then delivered into one of a number of batch peeling units each of which has peelers/cutters having cutting surfaces with a coating of carborundum. The coating on the cutters wears off over a period of time and we have found that for optimum processing efliciency the pccler to which the potatoes are directed is selected based on downstream processing considerations to maximise throughput. In the ease of a peeler with freshly coated cutting blades the residence time required to peel the potatoes can be as low as 5 seconds but can be up to 100 seconds if the pccler requires freshly coated cutting blades. A balance is achieved between achieving optimum peeling efficiency without surlace blemishes and throughput requirements.

The peeled potatoes are then passed over a sizing mesh. Potatoes below a size ol‘ about 75mm pass through the mesh and larger ones which do not pass through the mesh are directed to a halving device which cuts the large potatoes in halt‘ across the widest axis as orientated by a set ofoblong rollers. The halved potatoes are rctttmcd to the main processing stream of potatoes.

The potatoes are then sliced. The slice thickness is adjusted based on the solid content of the potatoes in the table below to ensure the process is controlled as uni lormly as possible. ‘f/it Solids or Dry Matter Slice thickness in thousandths ofan inch ;ii—2t.i _ 54-53 _' 21.2 21.9 54-53 ’2if0’-- 22.9 " 52 -- 56 “'T2".i’.8" 24.3 50 — 54 24.0-25.0 43-52 The slicer blades on each of the slicer heads are changed every 2 hours to ensure consistent slice thickness.

The potato slices are rinsed in cold water (less than 25%‘) to remove all cold water soluble starches which have an adverse impact on browning during coking. The removed starch can be recovered by centrifuging the waste water. The washed potato slices are then shaken using vibration to remove excess water. As detemiined by a fry test and colour measurement (Hunter Laboratory Instrument specitieation >55) on incoming potatoes the potato slices may then pass through a blanching process at a temperature of 600C - 80°C‘ or may bypass this process entirely. The blanched potatoes are then dried in an air blower which removes surface water which would have an adverse impact on frying. The dried potato slices are then delivered onto an accelerator conveyor which accelerates the potato slices and delivers them into a continuous in-line bath of cooking oil. lhc oil is |()()% sunflower oil.

In the oil the potato slices pass through three stages. In the first stage. the oil is at 1! temperature of l72°C to l79"C' preferably below l74°C and the slices lttt\'e a residence time of from 25 to 35 seconds. ideally about 30 seconds. In the second stage the oil is also at a temperature of l72°C to 176°C‘, preferably below l74"(‘ and the residence time is about 50 to 70 seconds, ideally about 60 seconds. In the third stage the oil is at a temperature of from 160°C to I64“(.‘. preferably below lo2"t‘ and the residence time is from 50 to 70 seconds. ideally about 60 seconds.

We have found that the processing in these three stages optimises the manufacture of good quality crisps. The first stage facilitates water removal. llic second stage aids colour lionnation whilst the third stage ensures that the crisps are lully cooked without burning. During passage through the bath ol hot oil. steam generated is removed and inay be used as an input For a heat recovery s} stem. 'l he quality ofthe cooked potato slices is then checked in-line. Any slices which are outside a defined specification and rejected prior to packaging.

Referring to Figs. I and 2, a crisp oil cooking bath 1 with a steam take-oft‘ hood 2 is illustrated. On discharge from the cooker, the crisps pass along a conveyor 3 and a guide arm 4 directs the crisps under an infra red detector 5. The IR detector is used to measure the moisture content and the fat content of the crisps in-line. ll‘ the moisture content is above 2% and/or the fat content is greater than a target which may, for example be 35%. the crisps are rejected as will be described in more detail below. The crisps all pass through a colour detector l0 in which the colour ofthe crisps is detected in-line to identify any crisps which have excessive browning/buming. An air blower is activated to blow any such crisps into a waste collecting chute I3, onto a conveyor I4 and into a waste collection bin I5. Crisps ' which meet the colour specification travel down a conveyor 20 leading to buckets | ofa bucket elevator 22.

The bucket elevator 22 delivers the crisps into an overhead chute 25. As will be particularly apparent from Figs. l and 3 the chute 25 has a gate 26 covering an opening 30 into a reject chute 3l leading to a waste bin 32. The gate 26 is perforated so that even when closed any small crisp pieces will fall through it and be discharged to waste 3|. 32. The gate 26 is pivotally mounted and is activated in response to a fault condition such as the lat and/or moisture content of the crisps. If the fat and/or moisture content is not within specification as measured in—|ine (described above) the gate 26 is opened and the crisps and discharged to waste 3|. 32.

There are significant improvements in crisp quality and increased throughput and yield as a result of the optimisation of the process. Crisps which do not meet the desired specilication are rejected eliliciently at an early stage of the process. belorc llavouring and packaging, Crisps which pass over the gate 26 are directed by a directing device 40 either into a holding area 41 or into a delivery chute 42 for feeding to a plurality of multihcad weighers 45. The holding area 4| is used to smooth out any variations in crisp production throughput and packaging throughput. If the packaging throughput is reduced the crisps may be directed along a feed conveyor 43 into the holding area 41 which may have a significant capacity, for example. equivalent to 20 minutes production. On demand, crisps from the holding area 4l are directed along an outleed conveyor 44 into the packaging feed chute 42.

Referring to Fig. 4, crisps may be directed to any one ofa plurality offlavouring station 50 which apply a llavouring and direct the crisps to an associated multi head weigher 5] which weigh out and deliver a required quantity ofcrisps into an associated vertical form fill and seal machine 52 which forms individual primary bags containing, for example 30g of crisps. The seal of the bag is then tested using a seal tester 53 and the weight is checked using a check wcighcr 54. As will he cleseribed in more detail below, the individual bags are collated in a collator S5. picked up 56 and placed into a magazine 57 prior to loading into a case/box which is then sealed 59. The scaled cases are then delivered along an output conveyor 60 for palletisation.

In more detail. and referring particularly to Figs. 5 to 9 a plurality oi‘ single packs 70 are delivered along conveyors 71 in two lanes 72 to a packztging station 75.

The packs 70 are arranged substantially horizontally and a suction lifter 76 travelling on a track 77 is used to lift up the packs 70 and deliver them into a magazine 78. A case/box 80 is aligned with the magazine 78 with the top opening of the box arranged vertically and a pusher 81 is used to deliver the two rows of packs into the box. The box 80 is then tumed through 90*‘ to upright the box so that the top opening is uppermost. The box is then sealed by a box sealing unit l5 83. ’| his arrangement greatly increases packing speed. In addition. because in storage. transit, and at the point of sale the bags are in a vertical orientation a number of benefits accrue. As there are two rows packed vertically. the bag seals '20 are tttaintained. Further. the bags can be more easily mechaniscd as groups of bags may be easily lifted out and placed in a merchandising unit without having the turn or re-arrange the bags.

Rcfctting in particular to Figs. 10 to 12 individual packs 70 of snack food products such as crisps may alternatively be packaged into multipack bags containing, for example. six individual bags. The primary bags 70 are delivered to one ofa plurality of multihead weighers 90. A plurality of tilled pritnary bags from the multihead weigher are then packed in an associated vertical form till and seal tmit 9] to form a multipack bag 93 containing the primary bags 70. The multipack bags 93 are check weighed 94. then collated in a collator 95 and then loaded into a case 96. The cases 96 containing the multipack bags 93 from the collating/packing stations are then delivered onto a conveyor 97 to a single aulumalic case sealer 98. A code on the case 96 is read and the case sealer 93 automatically adjusts to suil the case type and apply a seal and deliver lhc scaled ease along a cut feed conveyor 99 for palletisalion.

Iliis arrangement greatly increases packing efficiency. speed and thmLn_.-haul with lmx labour costs.

The invention is n01 limited to the embodiments hereinbelbre described which may be varied in detail.

Claims (1)

1. Claims A method for packaging snack lood products comprising the steps of :- manufacturing snack food products: delivering the snack food products into single primary bags: delivering the tilled primary bags to one of a plurality of multihead weighers: packing a plurality of filled primary bags from the multihcztd weighcr in a vertical form fill and seal unit to form a multipack bag containing a plurality ofthe primary packs; collating the multipack bags at one of a plurality of collating stations; loading the collated multipack bags into a case at the collating station; and delivering cases containing multipack bags from the collating stations to a single automatic case sealer. A method as claimed in claim l comprising the step of in-line seal testing ofthe multipack bags. A method as claimed in claim 1 or 2 comprising check weighing the multipack bags prior to collating the bags. A method as claimed in any ofclaims l to 3 comprising:- automatically reading 1] codc provided on the case: and automatically adjusting the case seal to correspond to the case to be scaled. A method as claimed in claimed in any ofclaims I to 4 wherein the snack food is a crisp product. A method as claimed in any ofclaims I to 5 wherein the snack food is a potato crisp product. A method for packaging snack food products substantially as hercinbcforc described with reference to the accompanying drawings.