Stabilised orange juice powder I. Preparation and packaging

VACUUM Classified A b s t r a c t s

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Vacuum

Processing

Techniques

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III

Abstract No. and References

Contd.

The Optical Absorption Constant of Cadmium Oxide Germany. R e f e r e n c e is m a d e to w o r k p u b l i s h e d b y Helwig on t h e electrical a n d optical properties o1 c a d m i u m oxide layers p r e p a r e d b y c a t h o d i c s p u t t e r i n g . Helwig s h o w e d t h a t b o t h t h e s e p r o p e r t i e s d e p e n d largely on the

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m e t h o d s of p r e p a r a t i o n a n d o n t h e t h e r m a l case h i s t o r y of t h e films. F i l m s s p u t t e r e d in a n oxygen-poor, o x y g e n n i t r o g e n a t m o s p h e r e t r a n s m i t b l u e - g r e e n light, w h e r e a s films t r e a t e d in a p u r e o x y g e n a t m o s p h e r e t r a n s m i t o n l y yellow a n d red light. T h i s c h a n g e of a b s o r p t i o n p r o p e r t y , i.e. t h e increase of t h e v a l u e of t h e a b s o r p t i o n c o n s t a n t , is a t t r i b u t e d to t h e order of m a g n i t u d e of self-absorption in t h e green r a n g e of tile s p e c t r u m . I t is t h e p u r p o s e of t h e i n v e s t i g a t i o n r e p o r t e d here to clarify t h e r e a s o n s for t h e c h a n g e in t h e optical p r o p e r t i e s in t h a t r a n g e of t h e s p e c t r u m . T h e a u t h o r p r e p a r e d t h e films to be e x a m i n e d b y t h e s a m e m e t h o d as described b y h i m p r e v i o u s l y (Z. Phys., x34 (1953), 194). A s i n d i c a t e d in H e l w i g ' s e x p e r i m e n t s it w a s f o u n d t h a t t h e a c t u a l region w h e r e t h e a b s o r p t i o n c o n s t a n t v a l u e s rise r a p i d l y a n d lead to sell-absorption, i.e. t h e a b s o r p t i o n wedge, at r o o m t e m p e r a t u r e d e p e n d s v e r y largely on t h e m e t h o d of t h e p r e p a r a t i o n of t h e film a n d its t h e r m a l case history. A n a n n e a l i n g t r e a t m e n t will shift t h e a b s o r p t i o n wedge a n d differences as h i g h as 0.S eV m a y be f o u n d H o w e v e r m e a s u r e m e n t s s h o w t h a t n o t t h e whole of tile a b s o r p t i o n c u r v e is shifted. I n fact o n l y t h e e x t r e m e end of t h e s e l f - a b s o r p t i o n is shifted a n d no c h a n g e s occur in t h e v a l u e s of t h e a b s o r p t i o n c o n s t a n t s in t h e r e m a i n d e r of t h e self-absorption region. Electrical c o n d u c t i v i t y a n d region of t h e a b s o r p t i o n w e d g e are closely related a t r o o m t e m p e r a t u r e . As t h e c o n d u c t i v i t y increases t h e position of t h e a b s o r p t i o n w e d g e m o v e s t o w a r d s t h e region of s h o r t e r w a v e l e n g t h s . T h e t e m p e r a t u r e d e p e n d e n c e of t h e v a l u e of t h e a b s o r p t i o n wedge is t h e s a m e as in t h e case of m o s t o t h e r s e m i - c o n d u c t o r s . A t h i g h t e m p e r a t u r e s it m o v e s in t h e direction of t h e region of long w a v e l e n g t h s . T w o t e n t a t i v e e x p l a n a t i o n s are g i v e n for t h i s b e h a v i o u r . Sommaire: Les films d ' o x y d e de c a d m i u m poss~de u n e b o n n e c o n d u c t i v i t 6 et u n e v a l e u r de la c o n s t a n t e d ' a b s o r p t i o n q u i n ' e s t p a s tr~s differente de celles des s e m i - c o n d u c t e u r s . Les propriOtds o p t i q u e s s e m b l e n t d 6 p e n d r e de la m 6 t h o d e de ddposition de la t o u c h e .

A Simple Method of Preparing Silica Replicas. Advantages Offered by the Cathodic Etching of Specimens

124/III

Article by ,1. Stuke Z. Phys. x37, No. 4 1954 401-415 125/III

See A b s t r a c t No. : 113,/I1

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IMPREGNATION--

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Silicate Impregnation of Porous Castings United Kingdom. I t h a s b e e n p r o p o s e d in t h e p a s t to e m p l o y a s o d i u m silicate solution c o n t a i n i n g p o t a s s i u m

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d i c h r o m a t e for t h e i m p r e g n a t i o n of a l u m i n i u m a n d m a g n e s i u m base alloys, a process f r e q u e n t l y e m p l o y e d to m i n i m i s e porosity, i t h a s been f o u n d t h a t s u c h a solution c o n t a i n s a n alkali radical w h i c h a t t a c k s a l u m i n i u m . I n order to o v e r c o m e t h i s difficulty it is s u g g e s t e d to a d d c h r o m i c acid to t h e solution. T h e preferred solution h a s t h e following composition: C h r o m i c acid 7 % b y weight, p o t a s s i u m d i c h r o m a t e 5 % b y w e i g h t a n d t h e b a l a n c e water, w a t e r glass 50 p a r t s b y v o l u m e . T h c l a t t e r h a s a s o d i u m silicate c o n t e n t of a b o u t 1 p a r t b y weight s o d i u m oxide a n d 2 p a r t s b y w e i g h t silicon dioxide. Processing details are given as follows: T h e c a s t i n g s are placed into a v a c u u m a u t o c l a v e w h i c h is e v a c u a t e d for a period of 30 m i n u t e s at a p r e s s u r e of no less t h a n 25 inch. Hg. T h e n t h e i m p r e g n a t i n g solution is a d m i t t e d at a t e m p e r a t u r e of a b o u t 95-100°C a n d positive p r e s s u r e of 6 0 - 8 0 p.s.i, is applied for a b o u t 30 m i n u t e s . A f t e r completion of t h i s t r e a t m e n t t h e c a s t i n g s are r e m o v e d , w a s h e d a n d h e a t e d for a b o u t 1 h o u r at 120¢C. Sommaire : Description d ' u n e m d t h o d e d ' i m p r d g n a t i o n sous vide des m o u l a g e s d'alliages 5 base d ' a l u m i n i u m et de m a g n e s i u m , e l u p l o y a u t u n e solution de silicate de s o d i u m c o n t e n a n t du b i c h r o m a t e de p o t a s s i u m et de. l'acide e h r o m i q u e p o u r le t r a i t e m e n t .

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DRYING

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L. E. Probert, W. A. Sutton F. Cork & Rolls-Royce Ltd. U.S. Pat.

2,680,081

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True Fruit Flavours See A b s t r a c t No. : 149/III

Stabilised Orange Juice Powder I. Preparation and Packaging United States. T h e p r e s e r v a t i o n of c o n c e n t r a t e d orange juice in t h e form of p o w d e r o b t a i n e d b y a puff-dryiflg

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process h a s been i n v e s t i g a t e d . T h e feed m a t e r i a l m o s t suitable for t h e process is h i g h d e n s i t y c o n c e n t r a t e c o n t a i n i n g u p to 6 5 % soluble solids as c a n be o b t a i n e d from p l a n t s p r o d u c i n g frozen c o n c e n t r a t e d orange juice. A l a y e r of t h i s c o n c e n t r a t e , 1 / 1 6 t h i n c h deep, w a s held b y t r a y s of a v a c u u m shelf dryer. T h e m a t e r i a l in t h e t r a y s w a s p r e h e a t e d to a t e m p e r a t u r e n o t e x c e e d i n g 38°C d u r i n g t h e pumping-dowx~ t i m e w h i c h took a b o u t 4 m i n u t e s (10 m m . Hg). W h e n o p e r a t i o n a l p r e s s u r e w a s r e a c h e d t h e t e m p e r a t u r e was raised to 200~F b u t due to t h e rapid e v o l u t i o n of w a t e r v a p o u r t h e t e m p e r a t u r e d r o p p e d to a b o u t 35~'F in t h e first t e n m i n u t e s before it b e g a n to rise again. A t this s t a g e a n appreciable evolution of gases t~)ok place which, because of t h e

July, 1954

Vacuum Vol. I V No. 3

383

VACUUM Classified A b s t r a c t s

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Vacuum

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Techniques

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Abstract, No.

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aml Refere.ces

Contd.

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viscosity of t h e c o n c e n t r a t e , c a u s e d tile c o n c e n t r a t e to swell i n s t e a d of s p a t t e r . During this phase which l a s t e d 20 m i n u t e s t h e t e m p e r a t u r e did n o t exceed 100°F b u t it t e n d e d to rise after t h e p u f f i n g p h a s e w h i c h would lead to o v e r h e a t i n g if left u n c o u t r o l l e d . After t o t a l d r y i n g t i m e of 90 m i n u t e s m o i s t u r e c o n t e n t was a b o u t 3 % . F i n a l shelf t e m p e r a t u r e should be 140"F. D u r i n g t h e process t h e feed grows to a t h i c k n e s s of a b o u t 2 inch. T h e t r a y s are silicon-coated to facilitate e a s y r e m o v a l of t h e p r o d u c t . T h e e n d p r o d u c t of d r y i n g is c r u s h e d into a p o w d e r of a b o u t 20 m e s h w h i c h h a s a b u l k d e n s i t y of 0.3 g . / m l , a n d can be easily r e c o n s t i t u t e d . F i n e r p o w d e r s do n o t r e c o n s t i t u t e e q u a l l y well. T h e p r e s s u r e d u r i n g t h e process s h o u l d p r e f e r a b l y be k e p t u n i f o r m a t 5 mnl. Hg. T h e a d d i t i o n of low-conversion s p r a y - d r i e d c o r n - s y r u p solids (24 d e x t r o s e e q u i v a l e n t ) r e s u l t i n g in a feed h a v i n g 6 0 ~ o r a n g e solids a n d 4 0 % c o r n - s y r u p solids increases t h e r e a d i n e s s of t h e m a t e r i a l to puff. F l a w ) u r was a d d e d to t h e finished p o w d e r b y a d m i x i n g sorbitol-oil g r a n u l e s j u s t before p a c k a g i n g . D e t a i l s of t h e p r e p a r a t i o n of t h e sorbitol-oil m i x t u r e are given. To keep t h e cost of t h e process low, in p a c k a g e desiccation is u s e d to r e m o v e t h e r e s i d u a l m o i s t u r e f r o m t h e m a t e r i a l once it h a s been p a c k e d in h e r m e t i c a l l y sealed containers. T h e m o s t s u i t a b l e d e s i c c a n t m a t e r i a l is c a l c i u m oxide or calcined lime w h i c h is held in a sift-proof m o i s t u r e p e r m e a b l e p a p e r b a g a n d placed in t h e c o n t a i n e r prior to sealing. A n a m o u n t of d e s i c c a n t e q u a l 10% of t h e w e i g h t of t h e o r a n g e p o w d e r in t h e c a n will keep t h e o r a n g e p o w d e r s u b s t a n t i a l l y at zero m o i s t u r e c o n t e n t . E x p e r i m e n t s w i t h a c o n t i n u o u s b e l t - t y p e v a c u u m drier h a v e i n d i c a t e d t h a t o r a n g e powder puff-dried b y t h e m e t h o d described c a n be p r o d u c e d w i t h s u c h e q u i p m e n t u n d e r c o m m e r c i a l conditions. Sommaire : D e s c r i p t i o n de n o u v e a u x d d v e l o p p e m e n t s apportds d a n s la p r @ a r a t i o n , la s t a b i l i s a t i o n du p a r f u m et l ' e m b a l l a g e de p o u d r e de j u s d ' o r a n g e .

Stabilised O r a n g e J u i c e Powder. II. C h a n g e s D u r i n g Storage United States. O r a n g e juice p o w d e r p r e p a r e d b y t h e p u f f d r y i n g m e t h o d described in A b s t r a c t 128/1II h a s been t e s t e d to d e t e r m i n e tile factors w h i c h influence its s t a b i l i t y d u r i n g storage. All m a t e r i a l t e s t e d w a s packaged as described before u s i n g i n - p a c k a g e desiccation w i t h t h e help of calcined lime as t h e desiccant. 750 s a m p l e s were e m p l o y e d in t h e i n v e s t i g a t i o n to s t u d y t h e effects of a t m o s p h e r e , s t o r a g e t e m p e r a t u r e , t y p e of o r a n g e oil, m e t h o d of a d d i n g oil, i n - p a c k a g e d e s i c c a t i o n a n d a d d i t i o n of s u l p h u r dioxide. T h e s a m p l e s were p a c k e d in e n a m e l l e d c a n s (211 × 414), e a c h c a n c o n t a i n i n g 170 g. of powder. T h e c a n s were sealed in a s e m i - a u t o m a t i c double s e a m e r w h i c h w a s fitted w i t h a v a c u u m c h a m b e r w h i c h w a s u s e d for v a c u u m p a c k a g i n g at a p r e s s u r e of 29 inch. Hg. A f t e r p a c k i n g , controlled s a m p l e s were held a t - 3 0 ° F a n d t h e o t h e r s were s t o r e d at 70°F for a c o n d i t i o n i n g period of 75 d a y s . D u r i n g t h i s period t h e m o i s t u r e c o n t e n t of t h e s a m p l e w a s r e d u c e d from its initial 3~o to 1.4 a n d 1.7% for v a c u u m a n d air p a c k e d s a m p l e s respectively. A f t e r conditioning, g r o u p s of s a m p l e s were stored a t t e m p e r a t u r e s of 70°F, 90°F a n d 100°F a n d were e x a m i n e d a t r e g u l a r intervals. T h e m o i s t u r e c o n t e n t of t h e p o w d e r w a s f o u n d to be t h e m o s t i m p o r t a n t factor g o v e r n i n g s t o r a g e life. Moisture c o n t e n t s h o u l d p r e f e r a b l y be r e d u c e d below 10/0 d u r i n g t h e c o n d i t i o n i n g period before s t o r a g e a t h i g h t e m p e r a t u r e s . S t a b i l i t y w a s effected b y t h e m e t h o d of i n c o r p o r a t i n g orange oil in t h e powder, t h e a d d i t i o n of o r a n g e oil in sorbitol b e i n g m o r e s a t i s f a c t o r y t h a n t h e direct a d d i t i o n of oil. S t a b i l i t y w a s i m p r o v e d b y t h e a d d i t i o n of s m a l l q u a n t i t i e s of s u l p h u r dioxide to t h e powder. V a c u u m p a c k i n g r e s u l t e d in s l i g h t l y i m p r o v e d s t o r a g e stability. .\ g e n e r a l s u r v e y of t h e r e s u l t s is g i v e n in a t a b l e p a r t l y r e p r o d u c e d below.

Panel Score

Article by S. L St,rashun & W. F. Talburt Food TeehnoL Jan~.~51954

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of In-Package Desiccated Samples of Orange Powders Stored at 7 0 ° F (21°C) and l O 0 ° F (38~'C) Organoleptic Rating Type of Sample

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Storage at 100° F* 60 days l 120 days

Cold-pressed oil in sorbitoh Sulfite added, vacuum pack No sulfite added, vacuum pack

7.7 6.7

Terpeneless oil added directly to feed: Sulfite added, vacuum pacl~ No sulfite added, vacuum pack Sulfite added, air pack No sulfite added, air pack

7.1 6.7 6.2 5.5

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Storage at 70* F

180 days

180 days

360 days

7.4 ,~.l

6.9 (;.5

8.4 8.2

8.2 8.1

6.8 5.5 6.1 5.2

6.8 5.5 6.4 6.0

8.0 6.9 7.5 7.3

7.4 7.0 7.2 6.8

*Samples stored 75 days at 70°F prior to placing in storage at 100°F; rating at l0 is highly palatable; 6 is the limit of palatability; and 1 is extremely unpalatable.

Sommaire : R a p p o r t s u r les r d s u l t a t s d ' u n e 6 t u d e de s t o c k a g e de p o u d r e & o r a n g e c o n t e n a n t des sirops de cdrdales s6chds sous vide. Apparatus for Stirring a Reaction Mixture Through a Vapour-Tight Seal See A b s t r a c t No. : 125/II

July, 1954

Vacuum Vot. I V No. 3

Article by A. M. Mylne & V. S. Seamens Food Technol. January 1954 45-50 130,aii

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