Ice Cream and Other Frozen Desserts

Before we know it, the heat of summer will be upon us, and many of us will be consuming ice cream and other frozen sweets in an effort to keep cool. So long as our summertime frozen treats are reliably-certified, we do not think too much about how they are made or about the kashrus work that goes into certifying them.

Let’s digress a bit and peek into the world of frozen dessert production and its kashrus.
Ice Cream
Ice cream manufacture is somewhat complex, especially due to modern-day use of so many flavors and additives. Whereas old-fashioned ice cream was literally what its name states – cream (the fatty part of milk) that was frozen, sweetened and flavored – contemporary ice cream is one of the most complicated of dairy products.

How is ice cream manufactured in modern-day factories?

For the sake of clarity, we can break down ice cream processing into two phases:
1. Pre-pasteurization Phase
As is the case with most dairy products, ice cream must be pasteurized, which means that it is heated to very high temperatures in order to eliminate dangerous bacteria.

Prior to pasteurization, production begins with an ice cream base, which is a liquid blend of cream and other dairy additives. Cream is milk fat, and it is created by passing whole milk through a separator, which separates the milk into cream (milk fat) and skim (fat-free) milk. Some ice cream plants make their own cream from fresh milk, whereas others purchase it from outside cream sources.

The cream forms the bulk and body of the finished ice cream product. Some ice cream bases are intended to be low-fat, and non-fat dry milk (skim milk powder) or condensed skim milk are often incorporated in order to lower the fat ratio of the ice cream base. So, too, whey (a by-product of cheese-making) is often added as a low-fat, protein-rich filler.

Frequently, an ice cream base needs to be especially thick, smooth, light, or to have an otherwise enhanced texture. For this reason, stabilizers – ingredients used to endow a stable, specific texture – are used in many ice cream bases. These stabilizers can consist of gums, starches, gelatin (normally non-kosher!) and other components. Many stabilizers also function as preservatives, extending the shelf-life of ice cream, preventing it from prematurely decomposing into ice crystals. Sugars are also added to the ice cream base. These sugars are often in liquid form.

Most ice cream manufacturers use emulsifiers in their ice cream bases. Emulsifiers enable the blending of the various components of certain mixtures (such as the blending of oil and water based liquids) and create desirable molecular structures in the product. In the case of ice cream, emulsifiers also assist in the distribution of air in the product (to be discussed later in this article). Emulsifiers are often derived from fats (vegetable oil, beef tallow) by splitting the fat molecules into glycerin and fatty acids, and vegetable-sourced emulsifiers are often processed on equipment shared with tallow-based emulsifier production. Obviously, the kashrus of emulsifiers must be monitored extremely carefully.

Once the ice cream base is completed, it is homogenized, meaning that is sent though equipment (a homogenizer) that reduces the size of the fat (cream) globules and makes the texture smooth. The base is then pasteurized and is quickly cooled. In most cases, the ice cream base is homogenized and pasteurized repeatedly several times.
2. Post-Pasteurization Phase
After pasteurization, the product (hereafter referred to as the ice cream mix) is ready for further development. At this juncture, it is first aged, meaning that it rests for several hours in its cold, liquid state in order for its newly-formed molecular structures to stabilize.

Next, additives that could not be pasteurized (as the heat of pasteurization would damage them) come into the picture. The cold, still unfrozen mix travels through a flavor tank, where – you guessed it – flavors (as well as colors and variegates – confectionary syrups and ribbons, such as fudge, liquid peanut butter, marshmallow stripe, etc.) are added.

Subsequently, the mix enters a barrel freezer, where the mix is partially frozen, while lots of air is whipped into it. Without air to lighten it up, ice cream would be as heavy as an ice cube.

Following partial freezing and whipping, particulates – small solid and semi-solid materials (such as nuts, chips, candy bits) – may be added. Since the ice cream mix is not yet stiff, particulates blend in with ease.

The ice cream mix then moves to a either a filler, which fills it into containers, or into a molding machine, which shapes ice cream mix into molds, subsequently to be made into ice cream bars or sandwiches.

The product is then packaged, after which it is frozen solid (called hardening) in a blast freezer, where air at arctic temperatures is rapidly blown through to quickly harden the product, which can finally and legitimately be called ice cream.
Pareve Frozen Desserts – Sorbet, Water Ices & Twin Pops
These products’ manufacture follows the same basic route as ice cream.

A base is first made, consisting of water, sweetener and often stabilizers and emulsifiers. The base is then usually pasteurized, homogenized and cooled, after which flavors, colors and fruit purees may be added. Subsequently, the product is frozen, filled or molded, after which it is hardened.
Kashrus
To the surprise of most consumers, the majority of ice cream and frozen dessert factories (at least outside of Eretz Yisroel) which make kosher products are not fully-kosher facilities. This poses many serious challenges for kashrus agencies.

In order to address these challenges in an orderly fashion, let’s return to our two-phase ice cream production model and work through it as a mashgiach would.

Most ice cream and pareve frozen desserts are made without hashgacha temidis – full-time, on-site rabbinic supervision. Rather, a yotzei v’nichnas (in-and-out) mashgiach is assigned to conduct unannounced inspections as often as is deemed necessary. Thus, the kashrus agencies involved in these types of operations must implement iron-clad, ultra-tight systems to assure the kashrus of the products they certify, as the mashgiach is not there at all times to supervise.

In such cases, kashrus agencies insist that nearly every ingredient used in the ice cream base at the pre-pasteurization phase be kosher, regardless of the kashrus of the end product. The reason is that any non-kosher cream, whey, or other material used at this point may render the plant’s equipment non-kosher, since the blend is heated when it is pasteurized, and heat transfers non-kosher taste into equipment and compromises its kosher status. Therefore, even non-certified products must use kosher cream, whey, non-fat dry milk and so forth at the pre-pasteurization phase, or else the equipment will become non-kosher.

There is another reason for this zero-tolerance policy toward non-kosher ice cream base components. These components are of general use in most ice cream products, and there would be no way for a yotzei n’nichnas mashgiach to verify that the plant’s kosher ice cream does not contain non-kosher cream, whey and so forth, as these materials as not unique to product-specific formulas. Whereas some products have unique flavors and particulates, etc., enabling the mashgiach to track their use in many cases (see below), most ice cream base components are so general that ice cream factories’ documentation systems do not identify them by source.

An exception can be made, in very rare cases, for non-kosher stabilizers (which are more common in some other dairy products – especially yogurt and sour cream – but are somewhat less common in ice cream). Stabilizers typically form a very minute ratio of the finished product’s volume, and – when this is so – they are batel (nullified) as regards their ability to make production equipment non-kosher. Stabilizers are also very specific to each product’s formula, tailoring each product for a unique, targeted result; they are not general ingredients. Still, in such scenarios, the mashgiach must be able to track the exact use of each stabilizer to ensure that kosher-certified ice cream uses only kosher stabilizers, and this can be a tough task.

Emulsifiers are also used in miniscule ratios, but ice cream emulsifiers are more likely to derive from non-kosher sources than are ice cream stabilizers. Thus, the concern for their kashrus is very high, and most kashrus agencies do not permit the use of non-kosher emulsifiers in certified yotzei v’nichnas plants under any circumstances.

Aside from stabilizers, pre-pasteurization ingredients pose many kashrus issues that must be addressed by the certifying agency.

Although ”cream” generally refers to milk fat, as above, some ice cream plants use whey cream, which is a derivative of the cheese-making process, and is very kosher-sensitive. So, too, regular cream (technically called sweet cream) often contains some whey cream. Great vigilance must be exercised in assuring the acceptability of all cream used in the facility (see H-43).

Non-fat dry milk is usually far less of a problem, although it has proven to require kashrus certification, as it is dried into powder on equipment (called a spray dryer) that can be used for non-kosher materials. The same is true for condensed skim milk, which may share common condensing equipment with non-kosher products. Both of these items therefore need reliable hashgacha.

As noted above, whey is a by-product of cheese-making, and it needs reliable kashrus certification at all times.

At the post-pasteurization phase, things get less risky, but more varied. Although all additives are now incorporated at cold temperatures and the ice cream mix is rapidly passed though the production system, thus not posing any threat of non-kosher additives rendering the relevant equipment non-kosher, many plants do use an abundance of non-kosher variegates and particulates. Most marshmallow pieces are made from non-kosher gelatin (taken from the hides of pigs and nevelah cows); gum bits are usually not kosher (as the gum base may be made from gum powder dried on non-kosher equipment); some flavors have non-kosher components, and strawberry and other red colors and flavor/color blends often contain carmine, which is a dark red extract from beetles.

Most ice cream facilities utilize such non-kosher post-pasteurization additives. How can these facilities’ kosher products be properly certified?

Ice cream made without hashgacha temidis in plants that carry on non-kosher production needs to be manufactured as part of a kashrus system that accounts for and closely tracks the use of non-kosher additives. In these facilities, the mashgiach must know the formulas for all kosher ice cream products, and he must spend a lot of time reviewing the batch sheets (plant’s industrial recipes) and production logs to assure that non-kosher additives do not make their way into kosher products.

A major factor in this type of hashgacha is reliance on company records and procedures, and this can only be done if the records and procedures are in place for the company’s own needs; if a company records its formulas and keeps production logs solely for the mashgiach’s use, there is no way to rely on such data.

For example, if Jim’s Ice Cream Company features two types of Rocky Road ice cream – one with (non-kosher) marshmallow bits and one with (kosher) marshmallow ribbon variegate – and the plant does not normally record, as part of its internal, built-in protocol, what goes into each type of Rocky Road and relevant production data, then kashrus cannot be assured without on-site, full-time supervision when kosher product is manufactured, even if Jim, the plant manager, agrees to instruct his staff to record such information for the yotzei v’nichnas rabbi. Such information is not considered objective data that can be relied on for purposes of kashrus.

Thus, to sum up, certification is often granted with yotzei v’nichnas supervision at ice cream plants so long as there is a tight system to verify that: all pre-pasteurization ingredients are kosher; non-kosher post-pasteurization ingredients can be tracked, and there are objective records to confirm all formulas and production.
Hashgacha of Pareve Frozen Products
In nearly all cases, these types of products are manufactured in (dairy) ice cream plants. They share common pasteurization equipment, and kashering is therfore necessary to certify anything in these facilities as pareve. How is this dealt with?

The only area that needs direct kashering is normally the pasteurization line, meaning the balance tank (where product enters the system and its volume and flow are regulated), the pasteurizer and homogenizer. (The balance tank, homogenizer and pasteurizer are typically linked together.)

In hashgacha temidis operations, the mashgiach personally supervises the kashering. So long as the mashgiach understands exactly what must be done, per the directives of his kashrus agency’s office, it is simple enough.

In yotzei v’nichnas plants, kashering may at times be accomplished by working with the plant’s own sanitization system. This system, referred to as a “CIP” (Cleaning in Place), refers to the frequent, automated self-cleaning routine performed on all equipment, usually between each production campaign, as well as on a daily basis.

A standard CIP consists of several steps: a hot acid solution wash, a hot caustic solution wash, as well as a fresh water wash. Each of these steps may be performed repeatedly as part of every CIP, depending on the plant’s requirements.

Ideally, a yotzei v’nichnas hashgacha program would rely on a CIP system to actually kasher the equipment. All plants have built-in temperature recording devices that generate automated diagrams (called Taylor Charts), which enable the plant’s staff and government inspectors to verify temperatures reached at each CIP, and these charts should be able to be relied upon by a mashgiach as well. (The plant and government need to track CIP temperatures to assure that the equipment is cleaned well for reasons of product safety.)

The problem is that most CIP systems clean equipment at 160-180 degrees F, which is far below the required temperature for kashering with hag’alah (boiling water).

When this is the case, a kashrus agency often insists on hashgacha temidis for all kashering; alternatively, if the CIP system can be reprogrammed to always sanitize at hag’alah temperatures, it may be accepted as such, once it is rigged this way by the plant’s engineers and is then subject to a careful evaluation by a senior kashrus expert, who can verify that there is no way to perform a CIP any more at sub-kashering temperatures.

There is a significant aspect of kashering that is easy to miss. Pasteurization is usually performed by product passing through a heat exchanger (equipment where heat is rapidly transferred to and away from the product at great volumes). Heat exchangers in ice cream plants normally operate via “heating water” on the other side of the equipment’s internal wall that the product contacts, so that the heating water’s heat passes through the wall into the product and rapidly heats (pasteurizes) the product. Since we hold that taste of non-kosher or dairy materials may penetrate a wall which has kosher or pareve product on the other side (Yoreh Deah 92:5), the kashrus of the heating water becomes an issue, as the heating water has possibly absorbed taste from (dairy) ice cream through the heat exchanger’s internal wall, and that same heating water is now heating pareve product though that same wall, passing along heat and perhaps dairy taste.

To address this matter, kashrus agencies insist that new heating water be used for pareve production, or that the heating water be pagum – embittered with caustic chemicals – prior to pareve production. Verification that this is properly done may be difficult without personal confirmation by the mashgiach, as heat exchangers do not have automated recording devices to indicate when heating water is evacuated, and there is no easy way to assure that the embittering chemicals are present, short of personally sampling the heating water for bitter taste.

There is yet another challenge to kashering in ice cream plants, and this challenge applies to most kashering situations, including those done with a mashgaich temidi. Halacha stipulates that hag’alah cannot be done unless the equipment to be kashered is aino ben yomo – unused for hot foods in the 24-hour period prior to kashering. (Yoreh Deah 103:5) Most dairy factories operate every day, meaning that there is not a 24-hour period when the plant is shut down for its equipment to achieve aino ben yomo status. Many kashrus agencies adopt the position that embittering the equipment with a caustic solution at hag’alah temperatures is the equivalent of attaining aino ben yomo status, as caustic solution – like down-time of 24 hours – damages any taste absorbed in the equipment and enables hag’alah (Yoreh Deah 95:4, Chochmas Adam 48:16; see Aruch Ha-Shulchan 94:24), while other agencies will only certify pareve products at plants that they can assure are down for 24 hours prior. (Such plants usually shut down on Sundays.)
Rework
In modern food production, virtually nothing is wasted. Rejected product finds it way to new use, and by-product and refuse are recycled into all types of concoctions.

It is quite common for ice cream to be “off-spec”, meaning that it does not meet the specifications of the plant. Such ice cream may be too thick, lumpy, or thin; its flavor may be off; its color may not be the shade it was intended to be, and so forth. In such cases, the ice cream is often reworked back into the pasteurization system and re-used in a different flavor or variety of ice cream, where its value can be salvaged.

The most common type of rework involves chocolate ice cream. Due to its strong, thick and heavy taste, chocolate masks other flavors that may be blended into it. Therefore, ice cream plants most commonly rework off-spec ice cream of most other flavors into chocolate ice cream. Coffee and other dark, heavy varieties of ice cream can also contain rework.

When ice cream plants are not all-kosher, it is a big concern, as the kashrus agency must be able to verify that non-kosher rework is not used in kosher product.

Ice cream with allergens (nuts, wheat, etc.) is usually not reworked, and the same generally holds true for ice cream with exceptionally strong or tart flavors. So, too, ice cream varieties which contain particulates (such as non-kosher marshmallow pieces and gum bits) are not usually reworked. However, these are not hard rules. In fact, one ice cream plant visited by this author had equipment to sift out particulates from rework and use the remaining ice cream blend for incorporation into other types of ice cream. Obviously, this process does not eliminate every bit, fleck and residual taste of non-kosher particulates, and it thereby needs great scrutiny. The only rule here for a kashrus agency is that each case must be evaluated on its own and fully investigated, as anything is possible.

Ice cream is not what it used to be, nor are the (now massive) requirements of its kashrus supervision. To certify ice cream, kashrus agencies must be thoroughly familiar with both food technology and halacha.

OU Kosher Staff